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null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Does the content of this patent fall under the category of 'Physics'? | Should this patent be classified under 'Human Necessities'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.259766 | 0.018799 | 0.241211 | 0.000179 | 0.243164 | 0.009155 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Is this patent appropriately categorized as 'Physics'? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.087402 | 0.015442 | 0.091309 | 0.000805 | 0.079102 | 0.010986 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.091309 | 0.092773 | 0.161133 | 0.006683 | 0.080566 | 0.01001 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Is 'Physics' the correct technical category for the patent? | Is 'Textiles; Paper' the correct technical category for the patent? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.081543 | 0.000755 | 0.038574 | 0.000026 | 0.094238 | 0.002319 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Does the content of this patent fall under the category of 'Physics'? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.255859 | 0.006683 | 0.223633 | 0.005737 | 0.242188 | 0.010315 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Is this patent appropriately categorized as 'Physics'? | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.086426 | 0.003281 | 0.091309 | 0.000055 | 0.08252 | 0.001099 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Should this patent be classified under 'Physics'? | Does the content of this patent fall under the category of 'Electricity'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.091309 | 0.001099 | 0.154297 | 0.000261 | 0.080566 | 0.001244 |
null | disclosed is an improved lens designed for protective eyewear that includes a rugate filter for blocking visible blue light . the lens is well - suited for prescription or non - prescription eyewear , inclusive of ophthalmic lenses , sunglasses , polarized sunglasses , intraocular lenses and contact lenses . the lens at least includes a plastic , polycarbonate , trivex ® or glass lens with a rugate filter deposited thereon to selectively block visible blue light . the rugate filter may additionally be used in conjunction with a polarizing layer , dielectric layer and / or color tint in a lens sandwich configuration , to additionally give a high degree of uva and uvb protection with a well - balanced light transmission profile under all light conditions , thereby maximizing protection while preserving clarity of vision . fig1 is a perspective exploded sketch showing the various lens layers mentioned above according to a multi - layer embodiment of the present invention . in its simplest form , the present invention comprises a first lens layer 16 with a rugate filter 50 ( to be described ) deposited thereon for visible blue light protection . however , the rugate filter may optionally be incorporated with a polarizing layer 17 , and / or color tinted lens layers 16 , 18 in a lens sandwich configuration , to additionally provide a high degree of uva and uvb protection . in this case the lens layers are arranged in a sandwich configuration including a polarizing filter layer 17 bonded between two optical lens layers 16 , 18 , the latter being any two conforming glass , plastic ( cr - 39 ), polycarbonate , trivex ® or high - index plastic or glass layers , as a matter of design choice . it is , however , noteworthy that cr - 39 ( plastic ) or polycarbonate lens blanks are capable of molecular bonding , which may be molecularly - bonded about the polarizing filter layer 17 to provide better wear characteristics as follows . in addition , both the first lens layer 16 and second lens layer 17 may be colorized to increase contrast , such as with high - contrast blue - blocking amber - tint , color discriminating grey tint , or otherwise . this may be accomplished by conventional dip dyeing techniques as shown and described in u . s . pat . no . 4 , 245 , 991 . the optional tinting of one or both lens layers 16 , 18 with high - contrast blue - blocking amber - tint , color discriminating grey , or any other commercially available high - contrast tint will help to block uva and uvb and add a color - discriminating ( contrast ) capability to the visible transmission profile . the rugate filter 50 comprises alternating layers applied ( adhered or molecularly bonded ) to the exterior of the existing lens sandwich 16 - 18 , either as an outer layer 9 ( as shown ) or inner layer , to eliminate all visible blue light . the rugate filter 50 is a multiple dielectric layer filter composed of alternate layers of silicon nitride ( si 3 n 4 ) and silicon dioxide ( sio 2 ) or alternate layers of hafnium oxide ( hfo 2 ) and sio 2 . this layered structure varies the index of refraction to produce a profile with the desired optical properties . the rugate filter 50 according to the present invention is made as an effective bandstop filter to exhibit a controlled narrow - band light blocking profile . this effectively provides a rugate notch filter or “ interference filter ” with a deep , narrow rejection band that nevertheless provides a high , flat transmission for the rest of the spectrum . in accordance with the present invention , the alternate rugate filter 50 layers are stacked together to form a stop band , the stop band being defined at bandpass cutons of 400 nanometers ( nm ) and 475 nm , respectively . thus , the rugate filter will selectively block visible blue light between 400 nanometers ( nm ) and 475 nm . uv - a & amp ; b light below 400 nm will also be blocked by conventional methods to be described . the rugate filter 50 layers are each a gradient index structure having a sinusoidal refractive index profile . the properties of the rugate filter 50 layers are determined by the values of the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ). the refractive index as a function of thickness , n ( t ), is given by : n ( t )= na + ½ np sin ( 2 μt / p ) where p is the modulation period of the refractive index profile . a rugate filter will strongly reflect light at a wavelength of λ 0 = 2 nap . thus , given notch cutons of 400 nm and 475 nm , the average refractive index ( na ) and the peak - to - peak modulation of the refractive index ( np ) for each of the respective rugate filter 50 layers can easily be determined . the rugate filter 50 according to the present invention results in bandstop characteristics as shown in fig2 , which is a graph of the spectral transmittance of the rugate filter 50 measured from 290 nm to 1 , 400 nm . the entire visible blue light spectrum is eliminated between 400 nanometers ( nm ) and 475 nm . all other visible light is passed , inclusive of the uvb ( 290 nm to 320 nm ) and uva ( 321 nm to 399 nm ) range , plus the ir spectrum including the near infrared range ( from 700 nm to 1 , 400 nm ). thus , the rugate filter 50 effectively forms a stop band between 400 nanometers ( nm ) and 475 nm , achieving 99 % reduction of visible blue light . consequently , the rugate filter 50 as incorporated into the lens of the present invention to substantially preserve visual function over time . to form rugate filter 50 layers , a typical rugate deposition process may be used in which a low index material and high index material are deposited , the rate of deposit of the low index material being held constant while the rate for the high index material is varied to achieve the correct refractive index modulation in the deposited film . a combination of silicon , oxygen and nitrogen compounds may be used in specific ratios to provide a pre - defined variation in the index of refraction . for example , silicon dioxide ( sio 2 ) provides an index of refraction of about 1 . 5 while silicon nitride ( si 3 n 4 ) provides a value of about 2 . 0 . it should be noted that other combinations may be possible to achieve this desired light transmission profile . these materials are deposited by means of a plasma - enhanced chemical vapor deposition process ( pecvd ). see , for example , goetzelmann et al ., “ uv coatings produced with plasma - ion - assisted deposition ”, spie vol . 3738 , p . 48 - 57 ( september 1999 ), which describes the plasma - ion - assisted deposition for the production of multilayer coatings for the visible and nir spectral range including rugate filters . in the present case , rugate filter 50 coatings can be deposited on the lens layer 16 using an increment deposition approach in which the variation in the index of refraction is calculated to provide a rugate filter 50 which achieves the desired bandstop filter profile . the optical thickness ( ot ) of the layer being deposited may be obtained by measuring the reflectance ( r ) of the thin film at wavelengths away from the reflection band of the filter . a computer and a monochrometer are used in a known manner to control the deposition and monitoring . prior to beginning the deposition of thin film layers of filter 50 , the predetermined refractive index profile at 780 nm is stored in the memory of the computer . as the deposition process proceeds , the computer receives signals from the monochrometer that correspond to the thin film reflectance spectrum . using the reflectance spectrum detected by the monochrometer , the computer calculates a current optical thickness estimate . next , the refractive index specified by the predetermined profile for that optical thickness of the film is calculated . the computer then provides a control signal to drive an energy source so that the mixture of evaporated materials produces the specified refractive index for the current optical thickness . this process is repeated continuously until the deposited layer corresponds to the specified refractive index profile . deposition is terminated when the total predetermined optical thickness is achieved . this results in a single layer rugate 50 film having a continuously varying index of refraction along a thickness direction with a number of maxima and minima in the index . preferably , the rugate filter 50 used herein are color - neutral so as not to alter the light transmission profile of the other lens layers . see , for example , johnson et al ., “ color neutral rugate filters ”, spie vol . 2046 , p . 132 - 140 ( november 1993 ), which describes a transmissive rugate filter which is designed to reflect a portion of the visible spectrum and yet not appear to have a dominant color . in the lens sandwich embodiment , high - contrast blue - blocking amber or grey cr - 39 lens layers 16 , 18 block uva and uvb light , the polarizing filter layer 17 adds dramatic glare blocking properties , and the rugate 50 adds visible blue light protection , all while maintaining an excellent light transmission profile . for the optional polarizing filter layer 17 , a conventional polarizing film filter is interposed between the two optical lens layers 16 , 18 as either a laminated or a cast suspended filter . laminated lenses are made by sandwiching the polarized film 17 between the two layers of plastic or polycarbonate or glass 16 , 18 , utilizing an adhesive to hold them together . however , adhesive can make the laminated lens appear hazy and the adhesion can fail when subjected to high heat and processing forces . cr - 39 ( plastic ) or polycarbonate lens blanks may be cast with a suspended polarizing filter 17 and need not rely upon adhesives to hold everything together . in this case , molecular bonding is used to chemically join the lens layers 16 - 18 , thus totally encapsulating the polarizing filter layer 17 between the two cr - 39 plastic lens layers 16 , 18 , thereby avoiding haze and delamination . the combination of the above - described rugate filter 50 , and optical lens layers 16 , 18 sandwiching a polarizing lens layer 17 , and color tints dramatically reduce glare and increase contrast in varying types of light conditions , and the sandwiched configuration is most durable for use in any environment . the light transmission properties of the improved multi - layer sunglass lens are optimized for maximum ocular safety . ultraviolet absorption of 100 % of uv - a & amp ; b light occurs to at least 400 nm , 99 % visible blue light reflection occurs between 400 - 475 nm , thereby preserving visual function , and visual acuity is preserved by a balance light transmission profile . in addition to the basic sandwich configuration described above , an optional multi - layered dielectric mirror layer 14 may be applied exteriorly ( over the rugate filter layer 50 or , if rugate layer 50 is placed interiorly , over outer optical lens layer 16 ). u . s . pat . no . 5 , 844 , 225 to kimock et al discloses an optical coating design formed in a multi - layer “ dielectric stack ” configuration for producing an anti - reflection feature , plus a method for fabricating a coated substrate product . kimock et al . &# 39 ; 225 also suggests various stacked layers inclusive of titanium oxide , nitride , zirconium nitride , boron nitride , yttrium oxide , silicon oxide , silicon dioxide , zirconium oxide , silicon carbide , aluminum oxide , aluminum nitride , and various mixtures thereof . the optional multi - layered dielectric mirror layer 14 may be applied using a similar method to create a stacked layer which actually comprises six equal - thickness thin film layers ( 2 - 3 nm total ) of titanium oxide , silicon dioxide ( quartz ), zirconium oxide , and chromium , each thin film layer being vacuum deposited separately in alternating 90 degree angles to provide a reflective mirror finish . dielectric mirrors in general combine high reflection values with outstanding durability characteristics . these coatings can generally exhibit significantly higher reflectance values than metallic films over specific wavelength intervals . the present stacked dielectric mirror layer 14 with particular constituents applied in alternating angular deposits further optimizes the lens to reduce light transmission through the entire uv and visible light spectrum , and may be used as desired to supplement the performance of the rugate filter 50 . finally , an optional hydrophobic overcoat 13 may be applied as an outermost layer 13 of the lens sandwich . the hydrophobic overcoat 13 is applied directly onto the dielectric layer 14 or rugate filter layer 50 depending on the chosen sandwich configuration . the hydrophobic coating is preferably a silicon - based chemical coating of known type such as commercially available from oms , 177108 canada inc ., 5120 courtrai , suite 12 , montreal , quebec , canada h3w 1a7 . this coating 13 may be deposited by known dipping or chemical vapor deposition processes , and it makes the lens water repellant for better vision during rainstorms or water related activities . in addition , hydrophobic overcoat 13 makes the lens easier to clean as contaminants do not adhere to the lubricated lens surface easily . moreover , the hydrophobic overcoat 13 resists smudging and streaking due to environmental and body contaminants . this hydrophobic layer 13 also produces a sealing effect to protect the lens and other base coatings , and to increases the longevity of the underlying layers . the hydrophobic coating 13 bonds with the lens to create a barrier against dirt , repelling dust , grease and liquid . the coating is non - acidic . it allows the lens to be cleaned with a wiping cloth without cleaning solution . the hydrophobic coating does not optically change the lens properties . it is extremely durable water repellant and not only repels water , but any other undesirable matter , including salt spray . the hydrophobic coating also combats bacterial build - up as dirt and oils do not stay on the lens . having now fully set forth the preferred embodiment and certain modifications of the concept underlying the present invention , various other embodiments as well as certain variations and modifications of the embodiments herein shown and described will obviously occur to those skilled in the art upon becoming familiar with said underlying concept . it is to be understood , therefore , that the invention may be practiced otherwise than as specifically set forth herein . | Does the content of this patent fall under the category of 'Physics'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 3b8f13108178e8094eb7a115b7fcf24e5b6b6dd58ba8cc6f36dc6aa2d504511c | 0.255859 | 0.161133 | 0.223633 | 0.053467 | 0.242188 | 0.103516 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Does the content of this patent fall under the category of 'Electricity'? | Should this patent be classified under 'Human Necessities'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.004333 | 0.002625 | 0.000179 | 0.000123 | 0.002121 | 0.001411 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Is this patent appropriately categorized as 'Electricity'? | Is 'Performing Operations; Transporting' the correct technical category for the patent? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.007813 | 0.009399 | 0.000336 | 0.001595 | 0.001701 | 0.016357 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Should this patent be classified under 'Electricity'? | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.005737 | 0.000023 | 0.000132 | 0.00002 | 0.000912 | 0.000296 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Does the content of this patent fall under the category of 'Electricity'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.004456 | 0.001366 | 0.000179 | 0.000035 | 0.002121 | 0.007568 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Does the content of this patent fall under the category of 'Electricity'? | Does the content of this patent fall under the category of 'Fixed Constructions'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.004333 | 0.023682 | 0.000179 | 0.003479 | 0.002121 | 0.040771 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Does the content of this patent fall under the category of 'Electricity'? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.004333 | 0.00007 | 0.000179 | 0.000035 | 0.002121 | 0.000261 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Should this patent be classified under 'Electricity'? | Is this patent appropriately categorized as 'Physics'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.005737 | 0.121582 | 0.000132 | 0.026733 | 0.000912 | 0.095215 |
null | the following patents and patent applications are hereby incorporated by reference in their entirety as though fully and completely set forth herein : u . s . provisional application no . 60 / 031350 titled &# 34 ; spread spectrum cordless telephone system and method &# 34 ; and filed nov . 21 , 1996 , whose inventors are alan hendrickson , paul schnizlein , stephen t . janesch , and ed bell ; u . s . application ser . no . 08 / 975 , 142 , titled &# 34 ; passband dqpsk detector for a digital communications receiver front end &# 34 ; and filed nov . 20 , 1997 , whose inventors are alan hendrickson and paul schnizlein ; u . s . application ser . no . 08 / 968 , 202 , titled &# 34 ; an improved phase detector for carrier recovery in a dqpsk receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , alan hendrickson , and paul schnizlein ; u . s . application ser . no . 09 / 078 , 225 , titled &# 34 ; symbol - quality evaluation in a digital communications receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson ; u . s . application ser . no . 08 / 968 , 029 , titled &# 34 ; a carrier - recovery loop with stored initialization in a radio receiver &# 34 ; and filed nov . 12 , 1997 , whose inventors are stephen t . janesch , paul schnizlein , and ed bell ; and u . s . application ser . no . 09 / 078 , 145 , titled &# 34 ; a method for compensating filtering delays in a spread - spectrum receiver &# 34 ; and filed may 13 , 1998 , whose inventor is alan hendrickson , now u . s . pat . no . 5 , 940 , 435 . as shown in fig1 a digital communication system comprises at least one transmitter 100 and one receiver 150 for the communication of data . such communication systems are well known in the art . the system described in this figure uses differential quadriphase - shift keying ( dqpsk ) to convey data from a transmitter to a receiver . although not depicted here , other modulation schemes such as ask , fsk , and other variants of psk could also be used to convey the data . in the transmitter 100 , digital data 102 are provided to a modulator 106 . a transmitter reference oscillator 104 generates a sinusoidal carrier wave 105 for the modulator 106 . the digital data 102 are encoded onto the sinusoidal carrier wave 105 by the modulator 106 which shifts the carrier &# 39 ; s phase by multiples of 90 ° according to the technique of dqpsk modulation , a technique well - known in the art . in this technique , the modulator 106 shifts the phase of the carrier wave by multiples of 90 ° to generate a transmitted signal 108 ; these phase shifts are the symbols that encode the data . each symbol lasts for a duration of time t after which the next phase shift is introduced to the carrier . the differences in phase angle between successive symbols represent the transmitted data 102 . since there are four possible symbols ( shifts of 0 °, 90 °, 180 °, or 270 °) in qpsk modulation , each phase difference represents two bits of the transmitted data . the carrier wave &# 39 ; s frequency is determined by the reference oscillator 104 in the transmitter . the transmitted signal 108 is the sinusoidal carrier wave with the data - bearing phase shifts of duration t . the transmitted signal 108 is sent via a physical commnunication channel 190 to the receiver 150 . the channel depicted in this figure is a radio transmission system that modulates the transmitted signal onto a radio wave 194 with a frequency greater than the carrier wave frequency . the channel 190 depicted here comprises the radio - frequency ( rf ) modulator 192 , the radio wave 194 transmitted through the air , and the rf demodulator 196 . as would be known to one skilled in the art , other communications channels such as transmission line , waveguide , or optical fiber systems can of course be used instead of ( or in conjunction with ) the depicted radio transmission system . under ideal conditions the received signal 158 would be an exact replica of the transmitted signal 108 . in practice , however , there may be some differences between these two signals due to degradation suffered in the communication channel . in the receiver 150 , the received signal is demodulated by a demodulator 156 to extract the received data 152 . ideally , the received digital data 152 would replicate the transmitted digital data 102 , but in practice the two sets of data may differ due to decoding errors in the receiver , or degradation of the transmitted signal in the communications channel . to extract the data from the received signal , the demodulator 156 requires a reference signal that closely reproduces the carrier wave 105 . since the original carrier wave 105 is not usually available in the receiver unit , this reference 155 is generated by a reference oscillator 154 in the receiver . in a preferred embodiment of the receiver , the reference oscillator 154 is a digitally controlled oscillator ( dco ); that is , it accepts a digital input word that controls the frequency of the oscillator &# 39 ; s output . this oscillator 154 must match the frequency of the transmitter oscillator 104 that generated the carrier wave 105 : if the frequencies of the two oscillators are not matched , the receiver unit 150 cannot efficiently demodulate the transmitted signal . the receiver oscillator 154 can be built so that its natural frequency is close to that of the transmitter oscillator 104 , but due to variations in manufacturing and differences in operating environments there will be drifts between the two oscillators . to compensate for such offsets in frequency between the carrier wave and the receiver oscillator , the receiver oscillator is locked to the carrier wave by incorporating it into phase - locked loop ( pll ). the pll is a carrier - recovery loop 162 that ties the frequency of the receiver oscillator 154 to the frequency of the transmitter oscillator 104 . the feedback from the carrier - recovery loop 162 corrects offsets between the frequencies of the receiver oscillator and the carrier . the depiction of the receiver in fig1 includes a basic block diagram of the carrier - recovery loop 162 . the carrier - recovery loop 162 includes the basic elements of a pll : the receiver oscillator 154 , a phase detector 164 , and the loop filter 166 . fig2 shows an embodiment of the carrier - recovery loop 162 . the phase detector 164 receives the received signal 158 and the receiver reference signal 155 . with these two inputs , the phase detector 164 compares the receiver oscillator &# 39 ; s phase to the phase of the carrier wave and generates a digital phase error signal 165 indicative of the phase shift between them . the phase error signal 165 is then provided to the loop filter 166 which comprises a novel configuration as described below . the loop filter 166 uses digital processing elements to condition the phase error signal 165 to generate a feedback signal 167 ; this feedback signal is fed back to the digitally controlled receiver oscillator 154 to nullify its offset from the carrier frequency . in the implementation of the carrier - recovery loop presented in this figure , the digital feedback signal is fed back to the receiver oscillator 154 , which produces the receiver reference signal 155 . the receiver reference signal 155 is made available to the phase detector for comparison with the received signal 158 . as shown in fig2 the loop filter 166 comprises a multiplier 201 with a gain coefficient k1 , which receives the phase error signal 165 and provides an output to a digital adder 204 . the loop filter 166 also comprises a multiplier 202 with a gain coefficient k2 , which receives the phase error signal 165 and provides an output to an integrator 203 in the loop filter . the integrator 203 in turn provides an output to the digital adder 204 . the digital adder 204 provides the sum of its two inputs to the receiver oscillator 154 . the gain coefficients k1 and k2 in multipliers 201 and 202 are adjustable binary values stored in a memory 210 . the integrator 203 accumulates the value of the phase error signal 165 after it has been scaled by the gain coefficient k2 in multiplier 202 . the digital adder 204 combines this integrated signal with a version of the original phase error signal that has been scaled by the gain coefficient k1 in multiplier 201 . thus the complex - frequency transfer function of the loop filter is k 1 + k 2 / s . with this implementation of the loop filter , the complex - frequency transfer function h . sub . θ ( s ) for the full carrier - recovery loop is given by the following equation . ## equ1 ## here φ ( s ) represents the phase of the receiver oscillator ( in the complex - frequency domain ), and θ ( s ) represents the phase of the received signal 158 . the pll thus has a low - pass response to changes in input frequency . the time constant for its response is determined by the gain coefficients k1 and k2 . since the gain coefficients are binary values stored in the memory 210 , they can be adjusted to put the carrier - recovery loop into one of several different operating modes . in the present invention , the receiver has three operating modes : acquisition , tracking , and hold . to enter the acquisition mode , the receiver sets these coefficients to the appropriate acquisition values each time the receiver begins carrier recovery . in acquisition mode , the pll of the preferred embodiment has a low - pass response to input frequency change . the receiver changes from the acquisition to tracking mode by reprogramming the gain coefficients k1 and k2 in the loop filter to lower values that are appropriate when the oscillator is close in frequency to the received signal . in tracking mode , the values of k1 and k2 are reduced so that the pll slows its response time , thereby reducing its sensitivity to high - frequency noise . this change from acquisition mode to tracking mode occurs when the receiver oscillator is determined to be adequately matched to the frequency of the received signal . there are several possible criteria for changing between these modes . one criterion for making this switch from acquisition mode to tracking mode is that the recovered frequency should be within a set range ( typically 1 khz ) of the actual input frequency . a second requirement is useful in systems that receive digital data in these systems , the switch to tracking mode can be additionally delayed until the receiver has acquired a frame synchronization with the received signal . in hold mode the receiver oscillator is not allowed to adapt , so that it continues to produce its last known frequency . this mode is used to sustain the appropriate frequency during fades in the received signal . in this mode the gain coefficients k1 and k2 have values of zero . alternatively , this mode can be accomplished by holding the value of the digital feedback signal constant or by forcing the ( phase error ) input to the loop filter to zero . the latter means can be used to conserve power in tdd ( time - division duplex ) communication systems . it allows the clock to the multipliers for k1 and k2 and the integrator to be stopped during the transmit portion of the tdd frame , reducing their power requirements by up to a factor of two . the block diagram in fig3 shows an implementation of the preferred embodiment of the loop filter 166 . in this implementation , an input register 305 receives a 5 - bit number representing the digital phase error signal 165 . the bits of this number are sent to a multiplier 301 that multiplies them by the gain coefficients k1 and k2 . since these gain coefficients are powers of 2 , the multiplier works by shifting the input by an appropriate number of bits , as described below , to generate a 14 - bit product 325 in an output register 320 . the multiplier alternates between using k1 and k2 to multiply the phase error signal 305 , so the product 325 represents the phase error multiplied by k1 on one clock cycle , and then the phase error multiplied by k2 on the next clock cycle . the product 325 is sent to a time - multiplexed adder 330 that alternates its function from cycle to cycle . during a cycle in which it receives the product of k1 and the phase error signal from the multiplier 301 , it adds this product to a value that it receives from an integrator register 340 . the resulting sum is a 14 - bit number representing the feedback signal 167 , which is the output of the loop filter . on alternate cycles , the time - multiplexed adder 330 receives the product of k2 and the phase error signal from the multiplier 301 . during these cycles it adds the product to the value it receives from an integrator register 340 ; this sum 335 is then sent back to the integrator register 340 and is stored there . this implementation realizes the function of the loop filter 166 that was described in the discussion of fig2 . when the carrier recovery loop is in the hold mode , the input register is simply set to contain all zeroes , regardless of the value of the phase error 165 . the resulting feedback signal 167 is then also zero , as required for the hold mode . for the other two modes , tracking and acquisition , the multiplier multiplies the phase error signal 165 by the appropriate values of k1 and k2 . the multiplier 301 is implemented by the connections and elements contained in the dashed box in fig3 . the five bits in the input register 305 are sent via a set of connections 310 to fourteen selection units 315a - n . these selection units are each coupled to one of the bits in the multiplier &# 39 ; s output register , and they each copy either one of the bits from the input register or a zero into their corresponding bit in the output register . the different selection units are configured so that the output register receives a copy of the bits in the input register , but shifted by the appropriate number of places according to the multiplier ( k1or k2 ). fig4 presents a more detailed block diagram of the selection units 315a - n in the multiplier 301 . as described earlier , each selection unit receives one or more bits from the input register 305 via the a set of connections 310 . in this figure , these bits are shown as the binary inputs 410 for one of the selection units . the inputs are sent to a multiplexer 415 which selects one of them , or a zero 411 , as the selection unit &# 39 ; s output 420 . this output is sent to one of the bits in the multiplier &# 39 ; s output register ( as was shown in fig3 ). a logic block 440 controls the multiplexers 415 in the selection units 315a - n by generating a shift code 460 that determines which of the binary inputs 410 is selected by each multiplexer 415 . the logic block 440 chooses which input bit is selected by the multiplexer so that the multiplier output register 320 receives an appropriately shifted copy of the input register 305 . to determine the number of places by which the multiplier input 165 should be shifted , the logic block receives the four different values of the multiplier : the value of k1 for lock mode 431 , the value of k1 for acquisition mode 432 , the value of k2 for lock mode 433 , and the value of k2 for acquisition mode 434 . these values are pre - programmed into a memory as appropriate for the different modes . another input 450 to the logic block 440 indicates the cycle in the time - multiplexing ; that is , whether k1 or k2 is being used as a multiplier . the logic block 440 also has an input 455 that indicates the operating mode of the carrier recovery loop : lock or acquisition . these two inputs 450 and 455 determine which of the four multiplier values 431 - 434 is used by the logic block 440 . with this multiplier value , the logic block 440 generates the shift code 460 and provides it to the multiplexer 415 . in response to the shift code 460 , the multiplexer 415 selects one of the input bits 410 from the input register 305 or a zero 411 as the selection unit output 420 that is sent to the corresponding bit of the multiplier output register 320 . in this preferred embodiment , the output of the logic block 440 indicates the shift code , that is , the number of bits to shift the input value 165 stored in register 305 . the logic needed in block 440 to generate the shift code is easily implemented by one skilled in the art of logic design , and the multiplexer arrangement is well known as a &# 34 ; shifter &# 34 ; or &# 34 ; barrel shifter &# 34 ; the constraint that each of k1 and k2 be a power of 2 allows the shifter to function as a multiplier . this embodiment of the invention utilizes factors k1 and k2 that are less than 1 , thus negative powers of 2 ( k1 , k2 = 2 n ; n =- 1 , - 2 , - 3 , . . . ). however , in another embodiment of the present invention , the factors k1 and k2 can also take values that are greater than or equal to 1 ( k1 , k2 = 2 n ; n = 0 ,± 1 ,± 2 , ± 3 , . . . ), and the shift are chosen appropriately . the sequence of steps which constitute the carrier recovery are illustrated by the flowchart in fig5 . in this diagram , the bold blocks and flow - lines on the right indicate the steps and the flow between them , while the light boxes on the left indicate quantities that are calculated and used in these steps . from the starting conditions 501 , the first step 503 is to program the appropriate gain coefficients for the current operating mode into the memory 210 . the next step is to receive the received signal 505 . the error signal 165 representing the offset of the receiver oscillator 154 ( shown in fig1 and fig2 ) is generated in the next step 510 . the error signal 165 is filtered in the following step 515 according to the gain coefficients k1 and k2 received from memory 530 . this filtering step 515 generates the feedback signal 167 that is used in the next step 520 to adjust the receiver oscillator so that it better matches the received signal . after this adjustment , the recovery loop returns to its initial step 505 to repeat the procedure with a new sample of the received signal . the step 515 of filtering the error signal is expanded in fig6 . here the bold blocks and flow - lines in the middle of this figure indicate the filtering steps and the flow between them , while the light boxes on the left and right indicate quantities that are calculated and used in these steps . the start of the filtering procedure 601 is right after the error signal has been generated 510 ( as was shown in fig5 ). in the first step 610 of the filtering procedure the error signal 165 is multiplied by the gain coefficient k1 received from memory 530 to generate the product 650 of these two quantities . the product 650 is then added in the next step 615 with a signal 660 representing the integral of the error signal 165 multiplied by the gain coefficient k2 . the resulting sum is the digital feedback signal 167 , which is the output of the filtering procedure 515 . to update the integrated signal 660 , the next step 620 in the filtering procedure 515 multiplies the error signal 165 with the gain coefficient k2 received from memory 530 . the resulting product 655 is then added 625 to the integrated signal 660 . the resulting sum , which represents the incremented value of the integrated signal 660 , replaces the old value of the integrated signal 660 . having thus generated an updated value for the feedback signal 167 and the integrated signal 660 , the filtering procedure comes to a termination 699 , and the carrier recovery of fig5 proceeds to adjust the receiver oscillator in step 520 . in one embodiment of the invention , the integrated signal 660 is stored in a memory 665 ( shown in fig6 ) which then holds a stored integrator value . the value in this memory 665 is then used to as an initializing value for the integrated signal 660 . the memory 665 is operable to provide its value back to the integrated signal 660 when the carrier recovery loop begins to acquire a new phase lock . this feature of storing the integrated signal 660 in a memory 665 is especially useful in carrier recovery loops that are incorporated into some time - division duplexing ( tdd ) or time - division multiple access ( tdma ) transceivers , in which a unit alternates between receiving and transmitting data . it is a well - known problem in tdd and tdma radio architecture to have frequency shifts in reference oscillators between transmission and reception modes . this frequency pulling occurs due to operating differences between the transmission and reception modes , such as changes in the output impedance of a reference oscillator . in another embodiment of the invention , the receiver 150 and the rf demodulator 196 from fig1 are incorporated in a tdd radio transceiver along with a local transmitter and a local rf modulator . in this embodiment , an rf oscillator in the rf demodulator 196 is used to demodulate the rf signal 194 during reception , and is also is used by the local rf modulator to generate an rf carrier during transmission . the frequency of this oscillator undergoes transient frequency shifts as shown in fig7 a . in this graph , the rf oscillator frequency is plotted versus time over the duration of a tdd iframe . the vertical axis on the left of the figure indicates a center rf value f 0 . in this embodiment , the oscillator frequency , shown by the light curve , has a rapid positive jump when the transceiver begins to receive data . the rf oscillator frequency gradually returns to f 0 , then suffers a rapid negative jump as the transceiver switches to transmit data , and again gradually returns to f 0 . this pulling of the rf oscillator frequency can lead to significant data losses if it is not compensated , since the large frequency shifts place significant demands on the carrier - recovery loop 162 . if the carrier recovery loop fails to track the frequency shifts for a portion of the data reception , the received data will be lost for that portion of the reception . traditionally , this pulling has been compensated by rf design modifications of the rf demodulators 162 in the prior art . however , in this embodiment of the invention , the stored integrator value in the memory 665 can be used to remedy the effects of the rf frequency pulling . the heavy curve in fig7 a illustrates an example of the recovered frequency for the dco 154 in this tdd embodiment of the invention . the recovered frequency is at an intermediate frequency ( if ) that is lower than the frequency of the rf signal 194 , but variations in the rf oscillator frequency lead to corresponding variations in the recovered frequency . the vertical axis for the recovered frequency is on the right in the figure . the center value f 0 &# 39 ; on this axis indicates the corresponding phase - locked recovered frequency when the rf oscillator is at f 0 . variations in the rf oscillator lead to a corresponding hertz - for - hertz variation in the locked recovered frequency . thus , on this graph , the heavy curve showing the recovered frequency would lie on top of the light curve showing the rf oscillator frequency if the carrier - recovery loop 162 were ideally tracking the frequency - pulling of the rf oscillator . this would not , however , be the optimal condition for carrier recovery , since if the loop 162 is fast enough to track such a large sudden shift , then it may be too susceptible to high - frequency noise to maintain an adequate lock . instead , this tdd embodiment of the invention uses the digital word stored in the memory 665 to mitigate the effects of tdd frequency pulling . as shown by the heavy curve in fig7 a , over the duration of a tdd frame , the recovered frequency starts at some initial value f 1 &# 39 ; and may have a significant offset from the received signal as the carrier - recovery loop attempts to match the sudden change in received frequency . the tdd frames are structured so that no payload data are transmitted during the initial portion of each transmitted data frame . this portion , called the preamble , is used to allow feedback loops to settle during the initial reception of a data frame . at the end of the preamble , the recovered signal has come closer to its target value ( of lying on top of the rf oscillator curve ). the exact curve followed by the recovered frequency depends on the form of the frequency pulling and on the response characteristics of the carrier recovery loop 162 . the recovered frequency f 2 &# 39 ; at the end of the preamble is stored in memory 665 and is used as the initializing value for the recovery frequency at the beginning of the next received frame . as shown in fig7 b , by starting from this improved initial value f 2 &# 39 ; , the carrier - recovery loop more quickly approaches a phase lock during the second received frame . at the end of the preamble in the second received frame , the memory 665 stores a further - improved approximation f 3 &# 39 ; of the starting recovered frequency . this new approximation is used in the following frame , as shown in fig7 c . thus by building on values previously stored in memory 665 , the carrier - recovery loop 162 converges on a good initializing value for the start of a received data frame . this initializing value allows the carrier - recovery loop 162 to maintain a tight lock with the received signal 158 despite the transient frequency jumps in the rf oscillator of the rf demodulator 196 . it is to be understood that multiple variations , changes and modifications are possible in the aforementioned embodiments of the invention described herein . although certain illustrative embodiments of the invention have been shown and described here , a wide range of modification , change , and substitution is contemplated in the foregoing disclosure and , in some instances , some features of the present invention may be employed without a corresponding use of the other features . accordingly , it is appropriate that the foregoing description be construed broadly and understood as being given by way of illustration and example only , the spirit and scope of the invention being limited only by the appended claims . | Does the content of this patent fall under the category of 'Electricity'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 11def81c8b1c880a5ac352e104d38ad87c40f4f4ec52d9002ca4c5de6ea64941 | 0.004333 | 0.040771 | 0.000179 | 0.002548 | 0.002258 | 0.074707 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is 'Physics' the correct technical category for the patent? | Is 'Human Necessities' the correct technical category for the patent? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.054932 | 0.002975 | 0.012817 | 0.00007 | 0.024414 | 0.000828 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is 'Physics' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.057373 | 0.054932 | 0.012817 | 0.029297 | 0.024414 | 0.041992 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Does the content of this patent fall under the category of 'Physics'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.142578 | 0.000534 | 0.020386 | 0.000045 | 0.066406 | 0.000732 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.057373 | 0.001457 | 0.012817 | 0.00002 | 0.024414 | 0.001701 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.057373 | 0.00383 | 0.012451 | 0.002396 | 0.024414 | 0.008057 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is this patent appropriately categorized as 'Physics'? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.088867 | 0.001068 | 0.041992 | 0.000668 | 0.037354 | 0.009399 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Electricity'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.068359 | 0.006683 | 0.015869 | 0.00193 | 0.022949 | 0.000999 |
null | in the following description , like reference numerals indicate like components to enhance the understanding of the invention through the description of the drawings . also , although specific features , configurations , arrangements and steps are discussed below , it should be understood that such specificity is for illustrative purposes only . a person skilled in the relevant art will recognize that other features , configurations , arrangements and steps are useful without departing from the spirit and scope of the invention . as illustrated in fig1 , a pointing device 10 in accordance with an exemplary embodiment of the invention includes a base 12 , a puck 14 , a first magnet system 16 , and a second magnet system 18 . base 12 can be part of the case or other sub - assembly of a host device , such as a laptop computer , personal digital assistant ( pda ), cellular telephone , or hybrid thereof , or it can be a separate element . in the exemplary embodiment , base 12 has a lower portion 20 and an upper portion 22 , but in other embodiments it can comprise fewer elements or more elements and have any other suitable structure . first magnet system 16 comprises an annular magnet mounted in puck 14 , and second magnet system 18 comprises an annular magnet mounted in base 12 . although in the exemplary embodiment of the invention , first and second magnet systems 16 and 18 each comprises a single annular permanent magnet , in other embodiments each can comprise one or more magnets of any suitable shape and type arranged in any suitable manner . one or more of the magnets can be permanent magnets as in the exemplary embodiment , or one or more can be electromagnets , as indicated in generalized form in fig6 . still other magnet system combinations and variations will occur to persons skilled in the art to which the invention relates in view of the teachings herein . similarly , although puck 14 and first and second magnet systems 16 and 18 are shown recessed within an area of base 12 in the exemplary embodiment , with the magnets enclosed or covered by portions of puck 14 and base 12 ( as indicated by dashed line in fig1 ), in other embodiments the puck and the magnet systems can be disposed in or on the base , enclosed or exposed in whole or part , in any other suitable manner . in this context , the terms “ in ” and “ on ” as used herein are intended to be synonymous . a user can move puck 14 ( typically using his or her finger , as indicated in dashed line in fig2 ) by applying a lateral force , i . e ., a force in any direction substantially perpendicular to an axis 24 that is normal to a planar region in which puck 14 is movable . in the illustrated embodiment of the invention , the planar region is defined by a planar surface of base 12 on which puck 14 slides . ( indeed , although not shown for purposes of clarity , to minimize the sliding friction in such embodiments , one or both of the surfaces of puck 14 and base 12 in contact with each other can include teflon or other low - friction material .) nevertheless , in other embodiments , any other means for facilitating movement of the puck within a planar region can be used . the force that the user applies in the lateral direction slides puck 14 in that direction , as indicated by the arrows in fig3 - 4 . in this manner , a user can move puck 14 anywhere within the circular area of base 12 enclosed by the annular magnet of second magnet system 18 . it should be noted that fig1 - 4 are not to scale , and the user may need only a relatively small area in which to move puck 14 ; the distance a user moves puck 14 can be , for example , on the same order as that in which a user moves a conventional joystick , ibm trackpoint ™, or similar compact pointing device . also , although puck 14 is disc - shaped or puck - shaped in the exemplary embodiment and laterally suspended within the circular area solely by magnetic force , in other embodiments the puck can have any suitable shape and structure , can be a part of some other assembly or mechanism , and can move in other dimensions and be used in other manners in addition to what is described herein . the term “ puck ” is therefore intended to include within its scope of meaning all such structures . pointing device 10 further includes a transducer system having electrode pads 26 , 28 , 30 and 32 , which are electrically insulated from one another and from puck 14 . although illustrated for purposes of clarity as squares embedded or patterned in an upper surface of portion 22 of base 12 , in other embodiments they can have any other suitable structure , shape and arrangement . for example , they can be patterned on the reverse surface of portion 22 . four capacitances are defined by the amount that puck 14 overlaps each of electrode pads 26 , 28 , 30 and 32 . these capacitances change as puck 14 moves over electrode pads 26 , 28 , 30 and 32 . as illustrated in fig8 , an electronic controller 34 can determine the position or direction of movement of puck 14 from the changes in relative capacitance . puck 14 can also include a suitable sensor ( not shown for purposes of clarity ) that detects the presence of the user &# 39 ; s finger , i . e ., detects a downward force along axis 24 . the position or direction of movement of puck 14 is transmitted to the host device ( e . g ., laptop computer , pda , etc .) in response to detection of such a force . the host device typically uses this information to control the position and movement of a cursor displayed on a screen ( not shown ). with puck 14 offset from the center of the circular area in which it is movable ( e . g ., as shown in fig3 ), when the user lifts his or her finger , the magnetic force re - centers puck 14 in that area . also , when the user lifts his or her finger from puck 14 , the position or direction of movement of puck 14 is not transmitted to the host device ( or , alternatively , the host device is caused to ignore any position or direction information that may be transmitted ). thus , as with conventional pointing devices that re - center themselves , re - centering pointing device 10 does not affect the cursor position . the magnetic interaction that causes the above - described re - centering can readily be understood with further reference to fig5 . in the illustrated embodiment of the invention , surfaces of first magnet system 16 and second magnet system 18 that face or oppose each other have the same polarizations , thereby causing them to repel each other . thus , in this concentric magnet embodiment , the exterior annular surface of first magnet system 16 and the interior annular surface of second magnet system 18 can each have a “ south ” (“ s ”) polarization as shown or , alternatively , they can each have a “ north ” polarization . in other embodiments of the invention , the polarizations will depend upon the shape and arrangement of the magnets . note that when puck 14 is centered , as shown in fig1 , the repulsive magnetic forces act equally in all of the various lateral directions about puck 14 , with forces in opposing directions canceling each other . the resultant of these forces exerted upon puck 14 in all of the various directions is zero , and puck 14 remains centered with respect to base 12 . when the user moves puck 14 off center , the resultant force is no longer zero , and a force is exerted upon puck 14 in a direction toward the center . if the user then lifts his or her finger , the force moves puck 14 in that direction until it is re - centered . as illustrated in fig6 , in another embodiment of the invention , one or both of the magnet systems 36 and 38 can comprise an electromagnet ( as indicated by the windings depicted in generalized form around an annular core ). as noted above , one or both of the magnet systems can have any suitable number , combination and arrangement of permanent magnets , electromagnets and similar magnetic elements . as illustrated in fig7 , in still another embodiment of the invention , the second magnet system 39 comprises not only an annular magnet 40 but also another ( in this case , disc - shaped ) magnet 42 that at least to some extent levitates or supports the puck to counteract friction between the puck and the base . in other words , the resultant force exerted upon the puck by the magnetic repulsion between the second and first magnet systems 38 and 44 , respectively , has components in both lateral and axial directions , with the axial force opposing the weight of the puck . a similar effect could be obtained with a magnet that generates a field having an uncommon shape such that it exerts a force upon the puck having components in both the lateral and axial directions . counteracting frictional forces in this manner enables the puck to slide more smoothly over the base . it will be apparent to those skilled in the art that various modifications and variations can be made to this invention without departing from the spirit or scope of the invention . thus , it is intended that the present invention cover the modifications and variations of this invention provided that they come within the scope of any claims and their equivalents . with regard to the claims , no claim is intended to invoke the sixth paragraph of 35 u . s . c . section 112 unless it includes the term “ means for ” followed by a participle . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 581e0aec1c6f92f2dbe2b37f4603a70b452b40cab7e2422691bf1e0f43529b35 | 0.057373 | 0.046631 | 0.012817 | 0.035645 | 0.024414 | 0.059326 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is 'Human Necessities' the correct technical category for the patent? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.000881 | 0.003372 | 0.001244 | 0.000572 | 0.010681 | 0.002625 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.001984 | 0.400391 | 0.002975 | 0.365234 | 0.023315 | 0.263672 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.000261 | 0.023682 | 0.000534 | 0.008606 | 0.005066 | 0.023315 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.000261 | 0.000418 | 0.000534 | 0.000023 | 0.005066 | 0.009705 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Does the content of this patent fall under the category of 'Fixed Constructions'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.001984 | 0.042725 | 0.002975 | 0.048828 | 0.023315 | 0.154297 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is 'Physics' the correct technical category for the patent? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.000261 | 0.059326 | 0.000534 | 0.021973 | 0.005066 | 0.051758 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | Should this patent be classified under 'Electricity'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.003601 | 0.001099 | 0.000607 | 0.000534 | 0.02002 | 0.000149 |
null | in fig1 a freeze - drying unit is now described as an example of a facility with containers being charged and / or discharged and designated 1 . it includes a chamber 2 , in which support surfaces 3 are housed . the height of these support surfaces can be adjusted with the aid of a cylinder piston device 4 , which is not more closely detailed . on the one hand , this height adjustment facility permits the support surfaces 3 to be set to a certain charging height . secondly , with the aid of the cylinder piston device 4 , the support surfaces 3 can be shifted closer together to close the containers after the freeze drying procedure has been completed . one wall 5 of the chamber 2 is provided with a mouth 6 , which can be shut with the flap 7 . in front of the freeze - drying unit 1 at the level of the mouth 6 there a transfer table 8 , which is supported on the charging trolley 9 above the horizontal spindle 11 and the spindle nuts 12 . the transfer table 8 includes the actual table surface 13 and the slide 14 , which itself is arranged in the manner shown in ep - a - 391 208 such that , though not depicted with respect to the table surface 13 , it can be moved back and forth beyond the front side of the transfer table 8 in the manner shown in as ep - a - 391 208 . fig2 is an enlarged view of the area of the mouth 6 in the chamber wall 5 . the spindle guides 11 and 12 are extended such that the transfer table 8 can be moved up to the support surface 3 to be loaded , in such a manner that the top of this support surface 3 and the table surface 13 of the transfer table 8 constitute a single plane . the slide 14 , which includes the containers 15 located on the transfer table 8 with loosely fitted stoppers 16 , can be slid into the interior of the freeze - drying chamber 1 across the face of the transfer table ( see fig1 in which the inserted slide is depicted as a dashed line ). the edge 17 of the slide facing the mouth 6 in the chamber wall 5 , in the position according to fig1 can be lifted with a pair of side arms see the positions respectively outlined ). once the slide 14 has been inserted completely into the chamber 2 , the raising of the slide edge 17 is depicted first -- in dashes -- and then the withdrawal of the slide 14 . the containers 15 remain on the support surface 3 . subsequently , the charging of the next support surface 31 can be started or , if the last support surface has been filled up , the flap 7 is closed and the freeze drying process can be commenced . in order to charge a further support surface 3 , the transfer table 8 is filled again with containers 15 . this can be carried out by rolling the charging trolley 9 up to a formatting table ( not shown ) which , for example can be arranged opposite the mouth 6 . the transfer table 8 is then positioned in front of the formatting table . in order to be able to take up the flasks on the formatting table using the slide 14 , the edge 19 of the slide 14 also opposite the edge 17 can be lifted with the aid of the side arms 21 . the movement of the slide 14 is then carried out with edge 19 raised . once the slide 14 has taken up all of the containers from the suitably sized table , the edge 19 is lowered and the slide 14 is pulled back such that all of the containers are slid onto the surface to the transfer table 8 . centering bolt 22 and guide blocks 23 are provided to ensure that the charging trolley 9 is correctly positioned in front of the freeze - drying unit 1 or possibly also in front of the suitably sized table . there is the possibility of adjusting the height of the transfer table 8 , if support surfaces 3 having different heights have to be loaded . thus , the dead space in the freeze - drying changer 1 can be kept to a minimum . the size of mouth . 6 has to be dimensioned correspondingly . furthermore , the transfer table 8 can also be supported on the charging trolley 9 such that it can be rotated freely . then it suffices when only one of the edges 17 , 19 of the slide 14 can be raised , as then only the respective raisable edge can be positioned facing the suitably sized table or the support surface 3 to be charged or discharged . the back and forth movement of the slide 14 is also preformed with a spindle guide 25 , depicted in fig3 and arranged to the side of transfer table 8 . the slide 14 is guided back and forth in a sliding motion on the spindle 25 via the spindle nut 27 and the bracket 26 , which is solidly attached to the slide 14 . the slide 14 itself is equipped with rollers , which are not depicted in the figures . these are supported by the edges of the transfer table 13 , which simultaneously function as runners for the rollers . for a trouble - free transfer of the containers 15 on the surface of the transfer table 8 and from this to the support surfaces 3 ( and vice - versa ) it is required that respective adjacent surfaces form a flat surface . it has already been suggested that the table surface 13 of the transfer table 8 be equipped with a marginal section 31 , which faces the respective table or support surface 3 to be loaded or unloaded and that it be attached to the main section of the table surface 13 via a joint 32 in such a manner that the height of the free corner of section 31 can be adjusted . in this solution , stoppers are attached to the section 31 and define the position of the surface of the transfer table 8 . the stoppers are attached on the side of the section in such a way that they do not impair the transfer of the containers . referring to fig4 - 6 , the swiveling marginal section 31 of the transfer table 8 is subdivided into a plurality of tongues 33 , each of which can independently pivot around an axis 34 disposed parallel to the edge of the table surface 13 ( see in particular fig3 ). these tongues 33 have been provided with suitable stop faces 35 , which have been designed and mounted to the support surfaces 3 such that when the tongues 33 are placed on top of these stop faces 35 , they fit flush with the front edges of the support surfaces 3 . in the examples illustrated in fig4 to 6 , the ( front ) edge of the support surface 3 facing the transfer table 8 is equipped with a step as a stopper , which has a height corresponding to the thickness of the tongues 33 . when the tongues 33 are lying on the step 35 ( fig4 and 6 ), a virtually flat transfer surface is produced between the table surface 13 of the transfer table 8 and the top of the support surface 3 , even when the front edge of the support surface 3 is not exactly level . the stop face or step 35 is formed by metal rails ( not shown ) attached to the support surfaces 3 ( fig2 and 4 ). however , there is also the possibility of cutting it into the front edges of the support surfaces 3 ( fig4 ). in operation , the transfer table 8 is moved up to a support surface 3 such that it is initially slightly higher than the support surface ( fig5 ). in this position of the transfer table 8 the tongues 33 are lying on a support ledge 36 connected to the table and running under the tongues ( fig4 ). still the inclination of the tongues 33 is so slight that there is no danger of the containers 15 tipping over . the transfer table 8 is then lowered downwardly until the tongues 33 rest on the step 35 . the downward motion of the transfer table 8 can be controlled by a proximity switch 37 ( fig2 and 6 ) located underneath one of the tongues 33 . this proximity switch can be part of the support ledge 36 ( fig3 ). the proximity switch 37 is connected to a control module 39 ( fig2 ) via a connecting lead 38 . using this control module 39 , the downward motion of the transfer table 8 or the upward motion of the support surfaces 3 can be controlled using the cylinder piston facility 4 ( fig1 ). | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | 0.25 | b71941f4dd59e804c9e93aba6db1042ea48935305f88ae80b3f4e2d1979a5a3c | 0.000881 | 0.091309 | 0.001244 | 0.022949 | 0.010681 | 0.088867 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Human Necessities'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.091309 | 0.009705 | 0.012817 | 0.000169 | 0.044678 | 0.014954 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.091309 | 0.012817 | 0.012817 | 0.002396 | 0.044678 | 0.017456 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.074707 | 0.000854 | 0.009399 | 0.000007 | 0.034668 | 0.003372 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Should this patent be classified under 'Performing Operations; Transporting'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.040771 | 0.025513 | 0.002319 | 0.023682 | 0.018799 | 0.035156 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.074707 | 0.007568 | 0.009399 | 0.004761 | 0.034668 | 0.03418 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Physics'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.123535 | 0.03064 | 0.035156 | 0.003281 | 0.074707 | 0.029297 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Is this patent appropriately categorized as 'Electricity'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.123535 | 0.016357 | 0.035156 | 0.000431 | 0.074707 | 0.000393 |
null | the detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments contemplated by the inventor . the detailed description includes specific details for the purpose of providing a comprehensive understanding of the present invention . however , it will be apparent to those skilled in the art that the present invention may be practised without these specific details . the present invention relates generally to a process for storing and separating bitumen froth using an improved froth tank . fig2 shows one embodiment of a froth tank ( 10 ) useful in the present invention which generally defines an inner chamber ( 12 ) having a generally cylindrical upper portion ( 14 ) and a generally conical lower portion ( 16 ). a bridge portion ( 18 ) spans across the upper portion ( 14 ) to support a rotary drive assembly ( 20 ), a torque sensor ( 22 ), and a plurality of stationary pickets ( 24 ). the tank ( 10 ) can be open or closed to the external environment . a roof may be included to cover the tank ( 10 ) to prevent contamination and release of odors , and to maintain slurry temperature . such roofs are typically made from fiberglass plates which are supported by the tank ( 10 ) and the bridge portion ( 18 ). the rotary drive assembly ( 20 ) includes a motor ( not shown ) attached to a drive gear box ( not shown ). the motor may be of fixed or variable speed , and use any suitable motive power , such as an electric or hydraulic motor or a combustion engine . an elongate drive shaft ( 26 ) is mounted at a first end in operational engagement with the motor and at a second end to the apex of the conical portion ( 16 ). the drive shaft ( 26 ) is thus mounted in a substantially vertical orientation within the inner chamber ( 12 ) of the tank ( 10 ). the drive shaft ( 26 ) connects the rotary drive assembly ( 20 ) to a rake assembly which is mounted for rotation about a generally vertical axis within the conical portion ( 16 ) of the tank ( 10 ). the rake assembly comprises rake arms ( 28 ) which are attached to the drive shaft ( 26 ), and a plurality of generally vertical movable pickets ( 30 ) carried by the rake arms ( 28 ). the rake arms ( 28 ) may comprise generally straight or curved blades . the rake arms ( 28 ) are positioned at the apex of the conical position ( 16 ) of the tank ( 10 ) to move settled solids across the conical portion ( 16 ) of the tank ( 10 ) for “ funnelling ” or discharge at a central underflow outlet ( 32 ). in one embodiment , the slope of the conical portion ( 16 ) is about 1 : 6 , i . e ., the walls of the cone are at an angle of about 15 degrees . the movable pickets ( 30 ) extend parallel to one another vertically , and are sufficiently spaced apart to accommodate the downwardly projecting stationary pickets ( 24 ) therebetween . as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ). as a consequence of its connection to the rake assembly , the drive shaft ( 26 ) is subjected to very high torques when rotated . the degree of torque is dependent upon the resistance to rotation experienced by the drive shaft ( 26 ). this resistance arises primarily as a result of the rake arms ( 28 ) and movable pickets ( 30 ) encountering resistance as they rotate through the settled solids and bitumen froth , respectively . the torque sensor ( 22 ) is used to detect the torque exerted upon the drive shaft ( 26 ), and transmit signals representative of the measured or recorded torque to a controller ( not shown ). the controller may be operatively connected to the motor to control the operation of the drive shaft ( 26 ) based on the signals received from the torque sensor ( 22 ). the tank ( 10 ) includes an inlet ( not shown ) through which bitumen froth ( 34 ) is pumped into the tank ( 10 ) above the conical portion ( 16 ). the inlet is oriented tangential to the tank ( 10 ), thereby dampening the turbulence of the incoming bitumen froth ( 34 ) and generating a swirling flow when feeding the bitumen froth ( 34 ) into the inner chamber ( 12 ). outlets ( not shown ) are oriented tangential to the tank ( 10 ) to allow the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) to be separately withdrawn and further processed . in one embodiment , the bitumen froth outlet may be a circumferential weir or a surface floating discharge . the tank ( 10 ) is interconnected to other components ( such as , for example , valves ( 42 ), pumps ( 44 ), and other tanks , tailings ponds or plants ) by conduits which may be constructed from any suitable piping as is employed in the art . suitable piping includes , without limitation , plastic piping , galvanized metal piping , and stainless steel piping . the conduits have associated valves ( 42 ) which may be opened and closed to divert the flows of the separated bitumen froth , middlings , and tailings among the interconnected components . the valves ( 42 ) may comprise any suitable valve employed by those skilled in the art to permit , or prevent , the flow of the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) through a conduit . suitable valves ( 42 ) include , but are not limited to , gate valves , butterfly valves , and ball valves . bitumen froth may contain about 60 wt % bitumen , about 30 wt % water and about 10 wt % solid mineral material , of which a large proportion is fine mineral material . the bitumen which is present in a bitumen froth comprises both non - asphaltenic material and asphaltenes . the bitumen froth ( 34 ) is pumped into the froth storage tank ( 10 ) above the conical portion ( 16 ) of the tank ( 10 ). a portion of the solids settles during the residence time . in one embodiment , the residence time may range from between about two to about twenty - four hours , preferably about six to about eighteen hours , and most preferably about two to about four hours . during the residence time , the motor may be activated intermittently or continuously to operate the rotary drive assembly ( 20 ) at a desired speed , thereby rotating the drive shaft ( 26 ) and the rake arms ( 28 ). as the rake arms ( 28 ) rotate , the movable pickets ( 30 ) travel around the stationary pickets ( 24 ) through the bitumen froth ( 34 ), thereby generating flow channels which facilitate separation of a top layer of bitumen froth ( 36 ), a middle layer of middlings ( 38 ) ( i . e ., warm water , fines , residual bitumen ), and a bottom layer of coarse tailings ( 40 ) ( i . e ., warm water , coarse solids , residual bitumen ). the bitumen froth ( 36 ), middlings ( 38 ), and tailings ( 40 ) are then separately withdrawn and further processed . the upper bitumen - rich , reduced - solids layer ( 36 ) overflows the top of the tank ( 10 ), and is withdrawn for the froth treatment process which eliminates the aqueous and solid contaminants from the bitumen froth to produce a clean bitumen product ( i . e ., “ diluted bitumen ”) for downstream upgrading processes . the bitumen froth is diluted with a hydrocarbon solvent ( i . e ., either a paraffinic or naphthenic type diluent ) to reduce the viscosity and density of the oil phase , thereby accelerating the settling of the dispersed phase impurities by gravity or centrifugation the middlings ( 38 ) are withdrawn from the mid - section of the tank upper portion ( 14 ) and pumped to a secondary processing unit . the rake arms ( 28 ) move the settled solids ( 40 ) across the conical portion ( 16 ) of the tank ( 10 ). since the bottom of the tank ( 10 ) is conical shaped , the solids ( 40 ) are easily discharged downwardly into the central underflow outlet ( 32 ) to be withdrawn as an underflow and pumped to a tailings pond or secondary processing unit . using the present invention , it was found that the use of the cone - bottomed froth storage tank ( 10 ) having an internal rake assembly facilitates the storage of bitumen froth and the separation of the bitumen froth , middlings , and tailing . solids may be removed intermittently or continuously as warranted during the feed residence time to maintain the capacity and ability of the tank ( 10 ) to act as a surge vessel . the froth tank capacity is increased by approximately 25 - 30 % by eliminating solids accumulations . further , the tank ( 10 ) reduces the risk of sloughing of solids into the subsequent froth treatment process . about 30 - 40 % of solids and 15 - 20 % of water are pre - separated from the bitumen froth and rejected to tailings through the underflow stream of the froth tank ( 10 ). higher quality bitumen feed is thus produced for further upgrading , thereby minimizing malfunctions in downstream equipment and enhancing the overall productivity of the processing plants . by way of example , the middlings stream ( 38 ) can be amenable to further upgrading , for example , using a two - stage centrifugation process with naphtha added to reduce viscosity in a froth treatment plant ( pant 6 ). bitumen froth ( 36 ) can also be treated in a froth treatment plant but may be of sufficient quality ( i . e ., reduced solids and water content ) that a froth treatment plant can be bypassed and the bitumen froth ( 36 ) can go directly to upgraders such as cokers and the like . the tailings ( 40 ) may be sufficiently cleaned of bitumen that the tailings can be directly deposited in tailings deposit sites . in the alternative , residual bitumen in the tailings can be recaptured by recycling this stream back to the primary separation vessels ( psvs ) where the bitumen froth is originally formed . it will be appreciated by those skilled in the art that the tank ( 10 ) of the present invention may be used to remove solids present in various materials including , but not limited to , raw de - aerated bitumen froth ; bitumen froth diluted at low (& lt ; 0 . 8 w / w ) or normal ( 0 . 8 w / w ) naphtha : bitumen ratios ; high - density solids / pastes ; and the like . exemplary embodiments of the present invention are described in the following examples , which are set forth to aid in the understanding of the invention , and should not be construed to limit in any way the scope of the invention as defined in the claims which follow thereafter . pilot tests were conducted to assess the ability of a cone - bottomed , raked froth tank to function as a froth cleaner and storage tank ; the effects of bulk froth residence time , underflow split ratios , and feed compositions on solids / water and bitumen separation in the froth tank ; and the effect of stationary and movable pickets along with the rake arms on the separation of solids / water and bitumen . the experimental results indicate that the bulk froth residence time , underflow split ratio (“ u / f ,” the ratio of the underflow to the feed flow rate ), feed composition , and the use of pickets had significant effects on the separation between solids / water and bitumen in the froth tank . the locations of samples withdrawn at different elevations above the knuckle of the froth tank are shown in fig3 . the profiles of the sampled bitumen , water , solids and fines at residence times of 1 , 2 and 4 hours are shown graphically in fig4 and 5 . the effect of residence time on underflow component contents is shown in fig6 a - b . the effect of u / f split ratios on underflow component contents is shown in fig7 a - b , the effects of feed composition on underflow component contents when the u / f split ratio is 7 . 5 %, 15 % and 50 % are shown in fig8 a - b , 9 a - b , and 10 a - b , respectively . for the feed “ as is ,” a bulk residence time of 2 to 4 hours and a maximum u / f split ratio of 7 . 5 % were required to produce an underflow which could be rejected as tailings . the minimum bulk froth residence time in the tank may be 2 hours , but can be varied between 2 to 24 hours depending upon the froth tank size and the feed rate . the optimal underflow split ratio to feed was about 7 . 5 % by volume , but can be varied between 0 to 50 % by volume depending on the feed froth compositions . the use of pickets significantly improved the solids / water and the bitumen separation by creating channels within which solids / water easily settled downward ( fig1 a - b .) the optimal temperature of the de - aerated bitumen froth fed to the tank was about 80 ° c ., but can be varied between about 50 ° c . to 80 ° c . the froth tank was capable of producing a stream with & gt ; 90 % bitumen , 6 % water and 4 % solids from the top of the tank ; a middling stream with about 65 % bitumen , 25 % water and 10 % solids from the middle of the tank sidewall ; and an underflow stream with about 0 . 5 % bitumen , 44 % water and 55 . 5 % solids from the bottom of the tank . about 35 - 40 % of the solids and about 15 - 20 % of the water can thus be removed from bitumen froth before downstream processing . a suitable froth tank may be approximately forty meters in diameter , about eighteen meters in height , about 23 , 000 m 3 in volume , and have a cone slope of 1 : 6 in order to process about 1200 to 3500 m 3 per hour of feed , and to ensure the discharge of solids as tailings . the residence time may range between about 6 to 18 hours . the froth tank has an available volume for feed of about 20 , 000 m3 and operates at a level between about 15 - 90 %. the nominal capacity is about 125 kbbl . from the foregoing description , one skilled in the art can easily ascertain the essential characteristics of this invention , and without departing from the spirit and scope thereof , can make various changes and modifications of the invention to adapt it to various usages and conditions . thus , the present invention is not intended to be limited to the embodiments shown herein , but is to be accorded the full scope consistent with the claims , wherein reference to an element in the singular , such as by use of the article “ a ” or “ an ” is not intended to mean “ one and only one ” unless specifically so stated , but rather “ one or more ”. all structural and functional equivalents to the elements of the various embodiments described throughout the disclosure that are known or later come to be known to those of ordinary skill in the art are intended to be encompassed by the elements of the claims . moreover , nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims . the following references are incorporated herein by reference ( where permitted ) as if reproduced in their entirety . all references are indicative of the level of skill of those skilled in the art to which this invention pertains . du toit , w . f . liquids / solids separator . canadian patent application no . 2 , 214 , 538 , published sep . 26 , 1996 . tipman , r . n ., rajan , v . s . v . and wallace , e . d . process for increasing the bitumen content of oil sands froth . canadian patent no . 2 , 055 , 213 , issued aug . 13 , 1996 . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 45c31d923a839d3c0e6d8bf53419f95cd0bb0a3e0b7699954724f56580d88427 | 0.123535 | 0.094238 | 0.035156 | 0.051758 | 0.074707 | 0.094238 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Should this patent be classified under 'Human Necessities'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.419922 | 0.014954 | 0.359375 | 0.000626 | 0.222656 | 0.015869 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.488281 | 0.00038 | 0.361328 | 0.000231 | 0.291016 | 0.003281 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.386719 | 0.000018 | 0.285156 | 0.000001 | 0.277344 | 0.001167 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Fixed Constructions'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.498047 | 0.010681 | 0.361328 | 0.123535 | 0.291016 | 0.106934 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.498047 | 0.000203 | 0.361328 | 0.000116 | 0.291016 | 0.004059 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Physics'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.419922 | 0.030273 | 0.359375 | 0.007568 | 0.222656 | 0.048828 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Electricity'? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.417969 | 0.007813 | 0.376953 | 0.000732 | 0.222656 | 0.000473 |
null | the invention comprises a device attached to the rear of any relatively blunt based vehicle including , but not limited to tractor trailer combinations , delivery vehicles , recreational vehicles and buses , vans or any vehicle that has any vehicle that has an inherently blunt or flat aft face . the aft of the vehicle is unmodified except to act an attachment point for the device . the device when deployed forms one or more sealed aft cavities that extend from the body of the vehicle rearward while maintaining legal length limits . when the rear doors of the vehicle are opened the device stows in such a way to have no impact on the normal operation of the vehicle . with the rear doors closed the device can be deployed or remain in a collapsed condition to facilitate parking and maneuvering . when the doors are open the device and the doors lie in a generally flat position on the respective sides of the vehicle . the device itself consists of either rigid fins constructed of traditional rigid materials , including composite materials , or of a flexible materials inflated via the trucks air system , any of which , when deployed , acts to form a sealed open cavity on the aft face and open to the all direction . utilizing an inflatable system eliminates majority of the work required to stow the device for loading and unloading of the trailer . a key aspect of the design is the framework of the device which attaches to and is hinged to the edge of each door near the centerline of the trailer . this allows the device to be stowed along side the trailer when the doors are in the open position and does not require any additional clearance between the doors of the trailer and the side of the trailer to stow the device for loading and unloading . it is also possible to eliminate the need for the framework by designing a replacement door that integrally incorporates the device . the use of a flexible inflatable material may also preclude the need for a framework . fig1 illustrates a rear view of a trailer or truck 10 without a drag reduction device having doors 12 and 14 of rectangular shape in a closed position . the doors are respectfully mounted by means of hinges 16 on one side and 24 on the other side so as to move from their shown closed position to a fully retracted position where they are disposed parallel and adjacent to the opposite sides 20 and 22 of the vehicle . the present invention is concerned with providing , at the rear of vehicle , an air drag reducing device 24 which includes a pair of cavities 26 and 28 . as illustrated in fig2 , a first cavity 26 , a left hand cavity , has a generally elongated rectangular shape with an outside edge 30 and an inside edge 32 ( defining the long sides of the rectangle ) and a pair of opposite sides 34 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the first cavity has an open area 38 and a base panel 40 . each of these items , except the open area 38 ( 30 , 32 , 34 and 36 ) are defined as panels . the first cavity 26 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 40 and the inside panel 32 . similarly , the other cavity 28 , a right cavity , as illustrated in fig2 has a generally elongated rectangular shape with an outside edge 42 and an inside edge 44 ( defining the long sides of the rectangle ) and a pair of opposite sides 46 ( at the top of the vehicle ) and 48 ( at the floor level of the vehicle ) ( defining the short sides of the rectangle ). the right cavity has an open area 50 and a base panel 52 . each of these items , except the open area 50 ( 42 , 44 , 46 and 48 ) are defined as panels . the right cavity 28 has a frustum shape ( a bath tub like structure ), four sides , a base and an open face . the base of the cavity is fastened to a supporting member 15 at the intersection of the base panel 52 and the inside panel 56 . these cavities are preferably made of a light rigid material , such as a fiber composite material or a rigid plastic . the us government &# 39 ; s federal highway administration waives certain length requirements on trucks , trailers and other vehicles , if aerodynamic devices , such as the cavities do not extend more than 5 feet beyond the vehicle and provided they do not have the strength , rigidity , or mass to damage a vehicle or injure a vehicle or in a vehicle that strikes a trailer so equipped from the rear . additionally , such devices may not obscure tail lamps , turn signals , marker lamps , identification lamps , or any other required safety devices such as hazardous safety placards or conspicuity markings . the panels of are made of a light rigid material such as : a composite fiber , a rigid plastic material ; carbon fiber , aluminum ; or wood . the performance of the cavities as a drag reduction system is very dependent upon the sealing of all panel edges in cavities 26 and 28 . in particular , panels joining the base panel 40 to the side panels 30 , 32 , 34 , and 36 for the left handed cavity as well as the base panel 52 to the side panels 42 , 44 , 46 , and 48 for the right hand cavity : this sealing can be done by using ordinary bulb type seals , locking seals or a variety of sealing clamp strategies . the sealing needs to breakable when the cavities are moved to their storage positions , as discussed below . the detail in fig8 a and 8 b illustrate the nature of the sealing of the right aft cavity . panel 42 is sealed to panel 46 with seal 54 . panel 44 is sealed to panel 46 with seal 56 . similar sealing takes place the interfaces between panel 46 and base panel 28 ; the bottom panel 48 ; and the bottom panel 48 and panels 42 and 54 . similar sealing is done between the same panels in the left cavity . examples of possible sealing arrangement include a seal of the form of a bulb seal 58 or inside edge seal 60 or a similar seal that prevents any air from leaking from the cavity formed by the aft extending panels to the surrounding outer surface except out the aft open end of the cavity fig3 illustrates an isometric view of the drag reducing device 10 . there are two independent cavities 26 and 28 , one on each door ( not seen ). inside side panel 32 of left cavity 26 and inside side panel 44 of right cavity 28 are normal to the back of the vehicle and are in contact with each other . as discussed the base panel 40 and 52 of each cavity is fastened to a supporting member 15 . the outside side panels 30 and 42 of each cavity 26 and 28 and the short side panels 34 , 36 , 46 , and 48 may be angled inwardly in the range of 0 to 35 degrees , depending on the preferred geometry . an exemplary value for the outside panels 30 and 42 and the upper short side panels 34 and 46 is an angle of about 15 degrees . an exemplary value for the short side panels 36 and 48 is an angle of about 7 degrees . it is not required that all panels be angled the same amount . for optimum performance , cavities 26 and 28 need to have an open area facing rearward and have the sealed panel junctions as discussed above . each cavity has the base panel hinged to the inside panel , outside panel and the other two panels . the inside panel and the outside panel of each cavity is fastened to the two other panels . fig4 depicts the device in the fully retracted state . cavity 26 with its panels fold flat along the left side of the vehicle and in front of rear door 12 . cavity 28 with its panels fold flat along the left side of the vehicle and in front of rear door 14 . when access to the load in the vehicle is needed the device will be stowed as shown in fig4 and fig7 . for a rigid sided device a first example of the procedure of stowing would be : a . fasteners are released and seals broken allowing the cavity to be folded together ; b . sides and top and base of each cavity are folded together against the respective back doors ; c . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; e . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then flat against the vehicle side . for a rigid sided device a second example of the procedure would be : a . cavity units are released from door and swing out on hinge lines near the centerline of the vehicle ; c . entire assembly swings out of the way on the door hinge line whilst the cavity highline continues to move and then against the vehicle side ; d . fasteners are released and seals broken allowing the cavity to be folded together ; e . sides and top and base of each cavity are folded together against the respective side of the vehicle . c . cavity units are released from door and swing out if necessary or simply remain attached to the door and reside against the door ; e . entire assembly swings out of the way and then flat against the vehicle side . this motion is illustrated in fig5 to fig7 and contrasts with previous designs which tend to have hinge lines at or near the door hinge line . access to the vehicle is now possible and unchanged from the original vehicle configuration . after load access is complete the rear doors are closed , the devices is placed into its original position and the panels are deployed . additionally , there may be instances when it would be desirable to have the vehicle &# 39 ; s doors closed , but have the drag reducing apparatus in a stowed position . such instances include being in a crowded business district where multiple deliveries are being made and at the lower speed of travel with the inconvenience of moving the apparatus for each delivery outweighs any marginal fuel efficiency gain by use of the device . the user would use steps a . and b . of the first above described procedures . it is estimated that it takes 5 minutes to move the cavities from the deployed state and the retracted state . the illustrative embodiments and modifications thereto described hereinabove are merely exemplary . it is understood that other modifications to the illustrative embodiments will readily occur to persons of ordinary skill in the art . all such modifications and variations are deemed to be within the scope and spirit of the present invention as will be defined by the accompanying claims . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | 0.25 | a2e7d9d1bdd817759de4b07f8aded24dbcf80a8eefd4f71976953bdad103bd50 | 0.178711 | 0.079102 | 0.150391 | 0.059326 | 0.121094 | 0.06543 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Is this patent appropriately categorized as 'Human Necessities'? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.044678 | 0.007355 | 0.00592 | 0.002258 | 0.008301 | 0.014954 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Is this patent appropriately categorized as 'Human Necessities'? | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.04541 | 0.002182 | 0.00592 | 0.000357 | 0.008301 | 0.003937 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Is this patent appropriately categorized as 'Human Necessities'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.04541 | 0.00592 | 0.00592 | 0.000055 | 0.008301 | 0.016357 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Does the content of this patent fall under the category of 'Human Necessities'? | Is this patent appropriately categorized as 'Fixed Constructions'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.125 | 0.017944 | 0.006683 | 0.024048 | 0.028931 | 0.014526 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Does the content of this patent fall under the category of 'Human Necessities'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.123535 | 0.00193 | 0.006683 | 0.000357 | 0.028931 | 0.019775 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Should this patent be classified under 'Human Necessities'? | Should this patent be classified under 'Physics'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.036865 | 0.04541 | 0.000778 | 0.00193 | 0.003601 | 0.019409 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Does the content of this patent fall under the category of 'Human Necessities'? | Should this patent be classified under 'Electricity'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.123535 | 0.00007 | 0.006683 | 0.000019 | 0.031738 | 0.000023 |
null | for the purposes of promoting an understanding of the principles of the invention , reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same . it will nevertheless be understood that no limitation of the scope of the invention is thereby intended , such alterations and further modifications in the illustrated device , and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates . referring to fig1 there is illustrated an enema tip retention apparatus 20 including clamp member 21 , adjustable belt arrangement 22 , enema tube 23 and enema tip 24 . clamp member 21 includes a mounting plate portion 27 adjustable , releasable clamp 28 and collar buttons 29 and 30 which provide retaining means for securing clamp member 21 to adjustable belt arrangement 22 . belt arrangement 22 includes a first strap portion 31 which is variable in circumferential encompassing size by means of belt buckle 32 and adjustment holes 33 . looped around first strap portion 31 are retaining straps 36 and 37 whose length extension from first strap portions 31 in a downwardly direction is controlled by adjustment means 38 and 39 . adjustment means 38 and 39 ( see fig7 ) include a collar stickpin - type arrangement wherein the outermost enlarged end portions of pin 40 are inserted through strap holes and thereby disposed on opposite outwardly facing surfaces of their corresponding retaining straps . this arrangement securely forms an enclosing loop for each strap which surrounds first strap portion 31 . the free ends of retaining straps 36 and 37 each include a keyhole - shaped slot 41 and 42 , respectively , which are suitably sized and arranged for engagement with and receipt of collar buttons 29 and 30 . collar buttons 29 and 30 ( see fig1 a and 2 ) each include a base portion 45 , an enlarged head portion 46 and a reduced diameter portion 47 therebetween . the size and shape of collar buttons 29 and 30 is such that enlarged head portion 46 is able to pass through larger opening 48 of keyhole - shaped slots 41 and 42 but not the smaller oblong opening portion 49 . thus , the means of attachment of clamp member 21 to adjustable belt arrangement 22 is to insert collar buttons 29 and 30 into keyhole - shaped slots 41 and 42 and then pull outwardly on retaining straps 36 and 37 such that reduced diameter portions 47 are snugly anchored within smaller oblong openings 49 , and retained there due to the larger sizes of head portion 46 and base portion 45 . referring to fig2 clamp member 21 is illustrated in greater detail and includes a deformable tab portion 52 , a cooperating locking portion 53 , which has a series of ratchet teeth 54 , and a clearance aperture 55 located adjacent the common end of portions 52 and 53 . clearance aperture 55 extends through clamp member 21 , including mounting plate portion 27 . enema tube 23 is partially shown in both fig1 a and fig2 illustrations and is disposed within clearance aperture 55 . as deformable tab portion 52 and cooperating locking portion 53 are drawn together , by squeezing , the dimensional size of clearance aperture 55 is reduced , and a clamping action occurs around enema tube 23 thereby holding this tube in position . inasmuch as the longitudinal axis of clearance aperture 55 is substantially perpendicular to mounting plate portion 27 , it should be apparent that when clamp member 21 is oriented near the rectal opening of a patient and first strap portion is secured around the patient &# 39 ; s waist , that retaining straps 36 and 37 may be adjusted in length until clamp member 21 is drawn snugly up against the patient &# 39 ; s rectal opening so that the enema tube 23 and its joined enema tip 24 are retained in position within the patient . by securing the enema tube and tip in such a manner , the enema tip is unable to slip out of the patient as the patient turns from one side to the other and orients his body in various positions which the radiologist or physician may request as part of the fluoroscopy x - ray examination procedure . referring to fig3 and 5 , alternative arrangements of clamp member 21 are illustrated . while it should be understood that the preferred arrangement of clamp member 21 with respect to the remainder of apparatus 20 is to have the smooth surface of mounting plate portion 27 closest to the patient , it is possible to use an orientation wherein the collar button side of mounting plate portion 27 is closest to the patient . it is also possible to arrange adjustable , releasable clamp 28 such that the longitudinal axis of its clearance aperture is parallel with the surface of mounting plate portion 27 rather than being perpendicular to it . fig3 illustrates such an arrangement where clamp 28 is disposed on mounting plate portion 27 so that the longitudinal axis of clearance aperture 55 is substantially parallel with the surface of mounting plate portion 27 . also included is a tube 56 which is shown in section only and secured by clamp 28 . this tube may be a drainage tube or similar device and thus , the arrangement of fig3 is suitable for retaining such tubes in a fixed position so that drainage of the patient cavities can be achieved , such as the sinuses . while this particular arrangement may not be best suited for enema administering , the clamping concept is virtually the same as clamp member 21 and collar buttons 29 and 30 are provided for retention of this alternative clamp member when such drainage of cavities is desired to be achieved . referring to fig4 there is illustrated a clamp , enema tube and enema tip combination 59 which is a one - piece , integral , molded assembly . combination 59 includes an enema tube 60 , an enema tip 61 , a mounting plate 62 , a clearance hole grommet 63 , collar button 64 and collar button 65 . although fabricated as a molded , one - piece combination , it is possible that these various component parts could be individually molded and then fitted together in a press - fit manner such that grommet 63 would be anchored within mounting plate 62 and would provide a snug fit around the outside diameter of enema tube 60 such that the tube and tip 61 would be held securely in position within the patient . in this manner , collar buttons 64 and 65 would be utilized as has been previously explained for collar buttons 29 and 30 of fig1 . referring to fig5 the alternative clamp member of fig3 is illustrated and includes a tubular insert 69 which has a lateral cross section of a &# 34 ; c &# 34 ; shape . this insert is generally concentric with clearance aperture 55 and is suitable to adapt the inside diameter size of clearance aperture 55 to the outside diameter of tube 70 such that various - sized tubes can be held by the clamp member . all that is required for adaptation is to select the appropriately sized c - shaped insert with the desired thickness . the use of such inserts is also envisioned with clamp member 21 inasmuch as the orientation of the clamp 28 with respect to the mounting plate portion 27 , whether parallel or perpendicular , is equally well suited for the addition of such inserts . referring to fig6 an alternative arrangement of the fig1 apparatus is illustrated and although belt arrangement 71 is similar to belt arrangement 22 , the noted difference involves the design of retaining straps 72 and 73 which are joined together at the general location of the enema tube 74 and enema tip 75 by means of retaining portion 76 . retaining portion 76 serves virtually the same purpose as did the free ends of retaining straps 36 and 37 which were provided with keyhole - shaped slots 41 and 42 , respectively . in the fig6 illustration , keyhole - shaped slots 77 and 78 ( see fig8 ) are provided and the only difference between the retaining portion arrangement of fig1 and that of fig6 is that the two retaining straps 72 and 73 are joined together wherein their y - shaped configuration and union at two locations creates a clearance opening 79 . enema tube 74 and enema tip 75 are joined together and extend through a retaining flange 82 which includes two oppositely disposed collar buttons 83 and 84 which are suitably positioned and sized to fit within keyhole - shaped slots 77 and 78 . in order to insert retaining flange 82 into retaining portion 76 , the outer ends of flange 82 must be drawn together by bending flange 82 and then insert collar buttons 83 and 84 into the enlarged opening portions of slots 77 and 78 . by fabricating retaining flange 82 out of a resilient , flexible material , release from this bent position will cause the collar buttons to flip outwardly thereby locking them in position in the smaller oblong opening portions of slots 77 and 78 . this locking engagement securely retains the enema tube and enema tip as part of belt arrangement 71 . the free end of enema tube 74 is provided with a series of angularly arranged layers or serrations 85 and these provide a snug fit arrangement with flexible tube 86 which may be forced over the free end of enema tube 74 . tube 86 may then be connected to a source of barium for introduction into the patient . referring to fig9 an alternative arrangement to the retaining portion designs of fig1 and 6 is illustrated . retaining flange 89 is a separate component and includes keyhole - shaped slots 90 and 91 and a clearance opening 92 . retaining straps 93 and 94 are provided with collar buttons 95 and 96 , respectively , disposed at their free ends . as has been previously described , collar buttons 95 and 96 are arranged to be received by slots 90 and 91 for fixed retention of retaining flange 89 . the clearance opening 92 of retaining flange 89 is suitably sized to receive in a snugly - fit arrangement an enema tip and tube combination or similar tubular member . referring to fig1 and 11 , still further alternative arrangements are illustrated . in fig1 , mounting plate 99 is provided with a serrated tubular member 100 secured therethrough as well as collar buttons 101 and 102 . serrated tubular member 100 extends beyond each surface of mounting plate 99 a distance sufficient for the connection of enema tip 103 and enema tube 104 . by fabricating the enema tip and enema tube members out of a flexible resilient material , they may be easily axially forced over the extending portions of serrated tubular member 100 and firmly lock onto the serrated surfaces , thereby providing a fixed and integrally appearing arrangement . in fig1 , the enema tip 107 is secured to mounting plate 108 and has a free end 109 of a serrated tube design . in this arrangement , enema tube 110 will fit over the extending serrations of free end 109 and although the enema tip and mounting plate are an integral design , various enema tubes may be used in this particular combination . although a conventional enema tip and enema tube combination have been illustrated throughout this specification , it is to be understood that the retaining and clamping arrangements disclosed herein are equally suitable for use with various types and styles of enema tips and tubes , including , but not limited to , those disclosed in my copending patent application , ser . no . 39 , 502 , filed on may 16 , 1979 now abandoned . thus the arrangements disclosed herein are suitable for double - contrast studies in which air is introduced after the barium is evacuated . in fact , the arrangements disclosed in the specification are particularly well suited to such double - contrast studies in that the enema tube and tip can be retained within the patient throughout the study in a well - secured and comfortable manner and is not subject to slipping out or otherwise separating from its inserted position within the patient . thus , in combination with any of one the various barium and air combination tubes of my copending patent application , barium is first introduced and then evacuated and then air is subsequently introduced into the patient and all of these operations may be performed without the necessity to remove the enema tip from the patient . while the invention has been illustrated and described in detail in the drawings and foregoing description , the same is to be considered as illustrative and not restrictive in character , it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected . | Is 'Human Necessities' the correct technical category for the patent? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 62dfb0bdece8f84d709a894563ea3f06ad87a1df0b9533c3ed215ca652aafa92 | 0.00885 | 0.086426 | 0.000488 | 0.054932 | 0.00193 | 0.036133 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Should this patent be classified under 'Human Necessities'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.246094 | 0.022339 | 0.15332 | 0.000315 | 0.287109 | 0.015442 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.241211 | 0.051025 | 0.15332 | 0.051758 | 0.287109 | 0.026001 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.241211 | 0.001099 | 0.15332 | 0.000021 | 0.287109 | 0.005554 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.255859 | 0.036133 | 0.194336 | 0.031982 | 0.245117 | 0.031738 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.241211 | 0.010681 | 0.15332 | 0.004211 | 0.287109 | 0.036865 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Physics'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.241211 | 0.199219 | 0.15332 | 0.161133 | 0.287109 | 0.122559 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Is this patent appropriately categorized as 'Electricity'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.175781 | 0.003708 | 0.088867 | 0.006287 | 0.198242 | 0.000458 |
null | fig1 is an outward - facing exploded view of a wheel assembly 100 with wheel 200 and hub cap 300 , both configured to be mounted to a hub 1 and axle 10 of vehicle 15 . the wheel 200 includes a rim ( or flange ) section 210 , central hub section 220 with lug - receiving holes 230 and central bore 240 , and web ( or spoke ) section 250 . hub 1 includes holes therein ( not shown ) to allow threaded placement of lugs 20 which in turn allow threaded attachment of lug nuts 30 . the corresponding holes 230 formed in wheel 200 allow placement of lugs 20 through the aligned holes , while accompanying lug nuts 30 secure the wheel 200 to the hub 1 through the lugs 20 . a tire 50 is also mounted onto the rim section 210 of wheel 200 . in a preferred ( although not necessary ) embodiment , the hub cap 300 is made from a non - metallic material , such as plastic or related resin , examples of which may include acrylonitrile - butadiene - styrene ( abs ), polycarbonate or a combination thereof . the material may further include continuous or discontinuous fiber reinforcements , such as glass , polymers , ceramics or the like . the hub cap 300 includes an outer surface 310 and inner surface 320 . a body portion of hub cap 300 defines the general external configuration , while a wheel coupling portion , which cooperates with inner surface 320 and is discussed in more detail below , promotes secure connection between the hub cap 300 , and the wheel 200 or the lug nuts 30 , or both . in the present context , the outer surface of the hub cap 300 is that which is visible to an observer when the wheel 200 is mounted to an automobile or related vehicle and is covered by the hub cap 300 . accordingly , the outer surface 310 of hub cap 300 is configured to provide an aesthetically - pleasing cover for at least a portion of central hub section 220 , and may ( among other things ) be metallized with an appropriate coating to define a chrome - like or related appearance . the inner surface 320 may or may not include a metallized coating , depending on the need or on the method of manufacture . for example , a metallized coating may or may not be placed on the inner surface 320 , depending on whether the hub cap 300 is masked prior to coating deposition . in another variation on aesthetic enhancement , the hub cap may include molded - in coloring or have its outer surface painted . referring next to fig2 through 5 , views of the inner surface 320 of a two - piece embodiment of the hub cap 300 are shown . fig6 depicts its attachment to the lug nuts 30 of wheel 200 . fig2 is a cutaway view that shows the cooperation of the inner surface 320 and a series of circumferentially - spaced lug nut engaging members 340 that are integrally formed at a proximal end base 340 a on a lug nut engaging ring 350 . the lug nut engaging members 340 each define an arcuate structure 341 that extends axially inward to a distal end crown 340 b to affix the hub cap 300 to wheel 200 by engaging the lug nuts 30 . by its arcuate shape , each lug nut engaging member 340 exhibits greater flexural rigidity than a generally planar member , yet is not so rigid that the lug nut engaging member 340 may not be flexed when pressed upon by a lug nut 30 . as can be seen in the figures , the crown 340 b of each lug nut engaging member 340 may define a castellated structure 341 , and may further form a radially - projecting protrusion 342 that includes bevelling to facilitate engagement with a surface of lug nut 30 . the castellated structure 341 enhances the flexibility of the member 340 . the base 340 a of each of the lug nut engaging members 340 surrounds a generally circular aperture 351 formed in the ring 350 through which at least a portion of one or both of the lug 20 and lug nut 30 are configured to pass . resiliently - biased ring detents 353 are integrally formed on the ring 350 and spaced between adjacent lug nut engaging members 340 . they extend axially outward from the opposite side of the ring 350 from which the lug nut engaging members 340 are disposed . fig3 highlights the rear ( inward - facing ) cutaway view of the inner surface 320 , including a series of circumferentially - spaced bosses 323 defining rectangular mounting apertures 325 . the axially inward - facing surface of the mounting apertures 325 are axially coplanar with one another , and include bevels or chamfers 329 to promote the insertion and cooperation of resiliently - biased ring detents 353 . by integrally forming the bosses 323 into the inner surface 320 of the hub cap 300 , complexity of the molds required to form the hub cap 300 is reduced , as all features can be formed in the line of the mold draw as the mold opens . opposed slots 360 can be formed in the body portion of hub cap 300 to facilitate the insertion of a tool ( for example , a screwdriver ) with which to pry the hub cap 300 off a wheel 200 . the lowermost edge 370 is generally planar so that when placed in contact with an adjoining surface of wheel 200 , the hub cap 300 is properly oriented to avoid misalignment and concomitant hub cap wobble . fig4 and 5 show the ring 350 from axially opposing sides . fig4 shows the axially inward - facing side of ring 350 , from which the circumferentially - spaced lug nut engaging members 340 extend . as can be seen , the lug nut engaging members 340 are integrally formed into ring 350 . apertures 351 are formed in the ring 350 , and define a generally circular ( or at least semicircular ) shape . semicircular horizontal ribs 352 extend radially inward from ring 350 and cooperate with base 340 a of lug nut engaging member 340 to define a securing area for lug nut 30 and allow passage of lug 20 . in addition , horizontal ribs 352 may form a tiered structure to permit the innermost surface of lug nut 30 to rest on a shelf 352 a ( shown with greater clarity in fig1 ) while having portions of the lateral surface of lug nut 30 fit within the circumference partially defined by horizontal rib 352 . snap - fit detents ( also referred to as tabs ) 353 possess a resilient bias that is overcome when ring 350 is pushed into aperture 325 of boss 323 until the detents 353 snap into place . as shown in fig5 , the detents 353 include a proximal end 353 a that is adjacent the ring 350 and a distal end 353 b with pawls 353 c or related accentuated heads that are configured to secure the detent 353 to the portion of the boss 323 that surrounds aperture 325 . as stated earlier , the ring 350 can be made from a temperature - resistant material , such as a high - temperature plastic , ceramic or composite based on plastic or ceramic . one suitable material is a glass - reinforced nylon composite . anti - rotation standoffs 355 are formed on either the ring 350 or the lug nut engaging members 340 to engage one or more of the faceted surfaces 31 of the lug nut 30 to inhibit its rotation . fig6 shows a cutaway view of the engagement of the hub cap 300 to the wheel 200 through the use of the ring 350 , lug engaging members 340 , lugs 20 and lug nuts 30 . ring 350 is secured to the hub cap 300 by the snap - fit detents 353 that extend through aperture 325 formed in boss 323 that is integrally formed into inner surface 320 of the body portion of hub cap 300 . a bevelled connector 40 can be used to provide a secure mounting location for the distal end 340 b and corresponding radially - projecting protrusion 342 of lug nut engaging member 340 . the bevelled connector 40 can be either integrally formed with lug nut 30 , or can form a separate piece . referring next to fig7 , the inner surface 420 of a one - piece embodiment of the hub cap 400 is shown in cutaway view . unlike the embodiment of fig2 through 6 , this embodiment can be formed from a single molded part , as lug nut engaging members 440 are integrally formed into the inner surface 420 . as with the previous embodiment lug nut engaging members 340 , the lug nut engaging members 440 of fig7 define an arcuate structure 441 that extends axially inward from a proximal base 440 a to a distal end crown 440 b . as discussed above , in situations requiring prolonged high - temperature durability , appropriate parts , may be made from materials ( such as those previously discussed ) specifically configured for elevated temperature environments . in the present embodiment , if such elevated temperature capability were required , the entire hub cap 400 could be formed from such a material . referring next to fig8 , the use of a retaining wire 500 to provide additional radial support to lug nut engaging member 440 is shown . as previously mentioned , retaining wire 500 can be made of ceramics or high - temperature plastics ( including fiber - reinforced composites thereof ), metal or other high strength , heat - resistant material . projections 480 built into the inner surface 420 of hub cap 400 can be arranged to ensure a frictional fit of retaining wire 500 during wheel operation . it will be appreciated by those skilled in the art that the retaining wire 500 is compatible with either the presently - shown one - piece hub cap 400 or the two - piece hub cap 300 . fig8 also illustrates a different configuration for the anti - rotation standoffs 455 that includes longer flat sides that can contact a larger portion of one of the faceted surfaces 31 of lug nut 30 . as shown , standoff 455 can be integrally formed with the inner surface 420 . it will be further appreciated by those skilled in the art that either of the anti - rotation standoffs 355 or 455 are equally useable with either the one - piece or two - piece hub cap configurations . lug nut engaging member 440 may otherwise be similar to that shown previously , including having an arcuate crown 441 . as with the two - piece configuration shown earlier , the present one - piece configuration has a generally planar lowermost edge 470 to properly seat hub cap 400 with an adjoining surface of wheel 200 to avoid misalignment and related wobble . in addition , slot 460 formed in the side of hub cap 400 is included facilitate separation of the hub cap 400 from the wheel 200 . referring next to fig9 a through 11 , cooperation of the retaining wire 500 with the lug nut engaging member 340 of ring 350 is shown . each lug nut engaging member 340 may also include a stiffening rib 347 disposed longitudinally on the surface away from the side that engages the lug nut 30 . in addition to providing enhanced flexural rigidity , it can include a ledge 347 a to act as a contact point for retaining wire 500 to promote the aforementioned frictional fit . to that end , additional devices can be used , such as flexible retaining wire retention device 380 ( shown with particularity in fig9 a and 9b ) to cooperate with ledge 347 a or a projection similar to that depicted in fig8 . referring with particularity to fig1 , an alternative attachment scheme for retaining wire 500 is shown . in it , stiffening rib 349 is affixed to or formed on the radially outward - facing surface of lug nut engaging member 340 . to keep the ability of the lug nut engaging member 340 to flex , stiffening rib 349 could be affixed directly to ring 350 without contacting lug nut engaging member 340 . the top of stiffening rib 349 serves as a lower mounting surface of the retaining wire 500 , while a projection 390 forms an upper mounting surface to keep the retaining wire 500 in place . in one form , a tight friction fit may clamp the retaining wire 500 in place . other equivalents to the ledge 347 a and the upper surface of the stiffening rib 349 could also be employed to provide additional axial support to retaining wire 500 . for example , a projection ( not shown ) could be integrally formed around the periphery of ring 350 and extend axially a distance sufficient to contact an opposite side of retaining wire 500 from that of projection 390 . having described the invention in detail and by reference to preferred embodiments thereof , it will be apparent that modifications and variations are possible without departing from the scope of the invention defined in the appended claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | 0.25 | a0b2bd630db20f0a9e9af1f8fd8dae796adde84a7a1047f92af52ffb4a96bcc7 | 0.255859 | 0.094238 | 0.194336 | 0.002396 | 0.245117 | 0.049561 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Is 'Human Necessities' the correct technical category for the patent? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15625 | 0.003082 | 0.054932 | 0.000096 | 0.28125 | 0.001411 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Is 'Performing Operations; Transporting' the correct technical category for the patent? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15332 | 0.043457 | 0.054932 | 0.003937 | 0.28125 | 0.044678 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.271484 | 0.000278 | 0.211914 | 0.000012 | 0.351563 | 0.000488 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15625 | 0.002548 | 0.054932 | 0.000028 | 0.28125 | 0.038574 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Fixed Constructions'? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15625 | 0.063477 | 0.054932 | 0.162109 | 0.28125 | 0.182617 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is this patent appropriately categorized as 'Physics'? | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.349609 | 0.004456 | 0.503906 | 0.000158 | 0.53125 | 0.007568 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Electricity'? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15625 | 0.361328 | 0.054932 | 0.005371 | 0.28125 | 0.357422 |
null | fig1 shows an rf base station 100 having a signal generator 120 driving an antenna 110 . the signal generator 120 is activated and deactivated by a on / off control line 140 driven by the signal generator controller 130 . an optional circulator 170 is shown between the signal generator 120 and the antenna 110 which may take signals received by antenna 110 and route them to optional receiver 180 . receiver 180 then sends demodulated signals to the base station electronics which may be part of the signal generator controller 130 . the signal generator controller 130 has conceptually an external trigger input 150 and an external trigger output 160 . although these can be physically separate signals , the preferred embodiments combine them into a bidirectional signal . the signal generator controller 130 is programmed by an application controller ( shown later ) through input / output 170 . in a typical application , the signal generator controller 130 is programmed to activate the on / off control line 140 after a count n of trigger deactivations , where the count could be zero or greater . the application controller initiates an application command . if the count n programmed into the signal generator controller 130 is zero , the signal generator controller activates the signal generator 120 immediately . otherwise , the signal generator controller 130 continuously polls the trigger input 150 , counts deactivations , and activates the signal generator 120 after the count n is reached . the signal generator controller 130 could be implemented as a state machine using logic gates , a programmable logic device ( pld ), or an application specific integrated circuit ( asic ). creating a state machine using these techniques is well known . alternatively , the signal generator controller 130 could be implemented using a micro controller running a software polling program . writing a program to poll a general purpose micro controller input and activate a general purpose output uses well known techniques . fig2 shows a detail of a preferred implementation of the trigger input circuit . in a preferred embodiment , the trigger input 150 is a multi - state signal wire . the states can be detected using a comparator with a fixed threshold . comparator 220 compares the trigger input 150 to a threshold 240 which is set to a point between the states “ none active ” and “ one active .” the comparator 220 distinguishes these two states . comparator 210 compares the trigger input 150 to a threshold 230 which is set to a point between the states “ one active ” and “ more than one active .” the comparator 220 distinguishes these two states . thus the output of the circuit of fig2 distinguishes three states . the transition of signal 260 from “ one active ” to “ none active ” is counted as a trigger deactivation . the assertion of the signal 250 in the state “ more than one active ” indicates that more than one base station has its signal generator activated . this can be used as an error condition . fig3 shows a detail of a preferred implementation of the trigger output circuit . in a preferred application , the “ none active / one active ” input 310 is actually the rf field on / off signal 140 . the input 310 turns on or off a fixed current source 330 . the current source 330 drives the trigger out signal 160 , the current sinking into a fixed resistive terminator 320 . when the input 310 indicates “ none active ”, the current source is off , no current flows through the terminator 320 , and the voltage at trigger out 160 is zero . when the input 310 indicates “ one active ”, the current source is on , current flows through the terminator 320 , and the voltage at trigger out 160 is a fixed non - zero level . in a preferred implementation , multiple base stations have their trigger out signal 160 bused together , but there is only one terminator 320 . if more than one base station drives current into the terminator , a higher voltage indicating “ more than one active ” results on line 160 . fig4 shows a preferred implementation of a system of multiple base stations 100 connected to a single application controller 410 . for example , three base stations 102 , 104 , and 106 are shown , along with an optional article detector 480 . in the preferred embodiment , the base stations 102 , 104 , and 106 and application controller 410 are connected by a local area network 420 , but other connections are also contemplated . in the preferred embodiment , the external trigger in 150 and external trigger out 160 are a single bidirectional signal , and the trigger from the first , second , and third base stations are connected to a trigger bus 430 and a resistive terminator 320 . two rf tags 440 with associated tag electronics 450 , and tag antennas 460 are shown receiving rf radiation 470 from base station 104 . the tags 440 may optionally be relatively moving with respect to the base stations with a tag velocity 480 . one typical application , shown by the block diagram of fig5 is to identify all tags currently in the field . in this case , the first base station a would be programmed by the application controller in step 510 to turn on immediately , the second base station b after one trigger negation , and the third base station c after two negations . the application controller sends out the identification command in step 520 . once the base stations receive the identification command , the first base station a activates its rf field , performs its algorithm , sends out an external trigger negation signal on line 150 / 160 , and turns off in step 530 . the second base station b , sensing the first trigger negation , activates its rf field in step 540 and follows the same path . likewise , when the second base station b finishes sending and sends out the second trigger negation signal , the third base station c activates in step 550 . after all the base stations have completed their turns , the process is ended in step 560 . the timing between one base station turning off , and another base station turning on is critical . the time elapsed must be less than the time t max where a passive tag 440 ( a tag without a separate battery to provide the tag electronics 450 with power ) in the rf field loses so much energy that the tag electronics 450 no longer function . the time t max must also be less than a time t min where the tag can distinguish that the base station transmission has terminated , since the tags are programmed to reset themselves a time t min after transmission ceases from the base station . the time t max is preferably 1 millisecond , more preferably 100 microseconds , and most preferably 30 microseconds . this setup need only be performed once in making a single pass through the identification algorithm . 1 . only one command need be sent by the application controller 410 . this minimizes network 420 traffic and application controller 410 processing . 2 . the switch over among base stations is performed independent of application controller 410 processing and network 420 traffic . the switching time can be minimized and a worst case maximum switchover time t max can be specified . a second typical application is continuous identification shown in fig6 . in this variation , base station a is told by the application controller in step 610 that it is first in a ring of three base stations . base station b is told that it is second of three , and base station c the third of three . then the application controller sends out the identification command in step 620 . once base stations a , b , and c receive the identification command , base station a becomes active in step 630 . base station b is programmed to start after one trigger , and base station c after two triggers . once base station a completes , rather than terminating as before , it is reprogrammed to start again after two triggers . base stations b and c are programmed identically after they complete the first round . control passes to base station b in step 640 , and base station c in step 650 . the system returns to step 630 to cycle continuously . the result is a continuous identification , with control passing to base stations a , b , c , a , b , c and so on indefinitely . once again , there is no application controller 410 processing or network 420 traffic required as the identification process passes from base station to base station . the actual termination of the process of fig6 can be programmed to be after a tag is identified , after a preset time limit , after a command from the application controller , or other application determined criteria . a third typical application is processing a moving tag as shown schematically in fig4 . again the setup would be to transmit from base station a followed by base station b followed by base station c if the tag were known to always move in the direction where it would enter the zone of base station a followed by zone b followed by zone c , as an example , tags on a conveyer belt would enter the relevant zones sequentially . base station a , would first try to process the tag for a time corresponding to the time that a tag would be in the zone of base station a . once base station a completed its attempt , control would pass to base station b and then to base station c . in this application , the first trigger signal might come from a detector 480 which detected a moving object moving into the zone covered by base station a . in one preferred embodiment , the signal generator controller is a digital state machine whose input is the trigger and a programming mechanism . the output of the state machine is the rf field on / off control . in another preferred embodiment , the signal generator controller is a micro controller programmed to insure guaranteed response time . the trigger is a software readable input and the rf field on / off control is a software controlled output . when suitably programmed , the micro controller continuously polls the trigger input . in either preferred embodiment , the signal generator controller can be programmed to turn on the rf field after the trigger activates and deactivates one or more times , or turn off the rf field and record an error if the trigger indicates that more than one base station &# 39 ; s rf field is on . in one preferred embodiment , the trigger output is a single signal line with multiple states . in another preferred embodiment , the trigger output is a set of signal lines , each line having only two states . in another preferred embodiment , the trigger signal is a resistively terminated wire , and the driver is a current source . the resulting voltage across the termination is proportional to the number of base stations driving the trigger . in a preferred embodiment , the trigger signal is bidirectional , a single wire connected in a bus architecture to each base station . this single wire is both detected by and potentially driven by each base station . in a preferred system embodiment , multiple base stations covering a zone have their trigger circuits connected together in a bus structure . each base station is programmed to turn on its rf field based on a programmable count of trigger signals . the result is that the application controller need only initiate the first base station in the sequence , after which time the other base stations will activate in turn without further intervention from the application controller . the sequence can be a series , with the application command terminating after the final base station in the series completes , or it can be a loop , with the command continuing indefinitely until an event is detected . the event can be the detection of tags meeting a certain criteria , reaching a time limit , an object moving out of the zone covered by the tags , or the application controller indicating that the loop should terminate . in a preferred sequence , base stations which have overlapping fields are adjacent in the programmed sequence , so that tags within the overlap region do not detect the field switching . in an alternate preferred sequence , base stations turn on in a sequence related to the typical movement of the rf tag in the zone , so that the speed at which moving tags are located is optimized . given this disclosure , equivalent embodiments of this invention will be apparent to those skilled in the art . these embodiments are also within the contemplation of the inventors . a multiple two state digital wire encoding of the trigger state 430 rather than the multi - state analog encoding disclosed . a base station 100 with separate trigger in 150 and trigger out 160 rather than the bidirectional unified trigger signal 420 disclosed . a chaining of trigger signals rather than the bus architecture 420 disclosed . a star arrangement where a trigger pulse is sent from a base station , from the application controller , or from an event detector to a central location , which then sends a trigger pulse to all the base stations . | Is 'Physics' the correct technical category for the patent? | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | 0.25 | d10e45fcdd2d27c5b44912fe1b505fff49af1aeaeb99cee35dbf5035ca2678d8 | 0.15625 | 0.086426 | 0.054932 | 0.020996 | 0.28125 | 0.086426 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is 'Human Necessities' the correct technical category for the patent? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.005554 | 0.018311 | 0.000534 | 0.086426 | 0.002625 | 0.028442 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is this patent appropriately categorized as 'Human Necessities'? | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.027954 | 0.002121 | 0.009399 | 0.000149 | 0.056641 | 0.002121 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is 'Human Necessities' the correct technical category for the patent? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.005371 | 0.000938 | 0.000553 | 0.00014 | 0.002625 | 0.002625 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Does the content of this patent fall under the category of 'Human Necessities'? | Does the content of this patent fall under the category of 'Fixed Constructions'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.036133 | 0.117676 | 0.005371 | 0.466797 | 0.051025 | 0.098145 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is this patent appropriately categorized as 'Human Necessities'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.027954 | 0.001282 | 0.009399 | 0.000216 | 0.056641 | 0.0065 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Should this patent be classified under 'Human Necessities'? | Is this patent appropriately categorized as 'Physics'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.025146 | 0.099609 | 0.003372 | 0.032471 | 0.027954 | 0.039551 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is this patent appropriately categorized as 'Human Necessities'? | Is 'Electricity' the correct technical category for the patent? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.027954 | 0.000473 | 0.010681 | 0.000345 | 0.056641 | 0.000216 |
null | reference is first being made to fig1 that shows a general flow chart of an embodiment of the virtual treatment method in accordance with the invention . upon initiation 20 , a virtual diagnostic setup model is inputted . this model may be obtained by a number of different ways . the basis is a virtual teeth model obtained through a variety of teeth scanning or direct teeth imaging techniques , or through scanning or otherwise capturing a negative teeth impression or a positive teeth model . an example of a method for obtaining three - dimensional digital model of teeth is disclosed in u . s . pat . no . 6 , 099 , 314 . from such a model a virtual setup model may be obtained through an automatic or manual procedure in which the setup model the teeth are separated from one another in a manner that permits separate manipulation of the position of each of the teeth . at the next step 24 a set of orthodontic appliances is selected for subsequent association with the teeth . as will be appreciated , the invention is not limited to a specific set of orthodontic appliances and the general principle described herein applies to any selected set . however , in accordance with a preferred embodiment of the invention , the set of orthodontic appliances which is to be used is a straight wire set that comprises a straight wire and brackets . as known , each bracket has a horizontal slot for receiving the wire . in addition , similarly as in real life orthodontic treatment , other orthodontic appliances such as hooks , elastic components , and others may be included in the set . the selection of the set may be automatic by the system or may be manual . for selection of a set of orthodontic appliances , different options may be presented to the user , for example , sets of different manufacturers , and the orthodont may then choose the one most familiar to him or the set which he prefers to use . alternatively , rather than selecting a complete set , optionally the user may select individual components that together will comprise the set . at a next step 26 the appliances are attached to or made to associate with the teeth . in one embodiment of the invention this is an automatic operation . in such an embodiment , after selection of the set for orthodontic appliances , the brackets are automatically attached to teeth . in such an automatic attachment , the brackets are typically attached to the center point of the teeth crown ( namely at the center of the exposed surface of the teeth ). in accordance with another embodiment the user may be permitted to select the position of all or of only some of the brackets . once all brackets have been selected , a wire , typically a straight wire as pointed out above , is added , and the first sequence of orthodontic treatment follows . in this first sequence , teeth are repositioned in a manner so that all the wire - receiving slots on the brackets snap onto the wire . this causes all slots to align in the plane defined by the wire and the teeth to align in an overall arch is also defined by the wire . this step may be carried out , for example , in a manner as described in pct publication wo 99 / 34747 . thereby , a first treatment state of the virtual model is obtained . a more detailed description of the step appears further below . in a next step 30 , this initial treatment state is analyzed and graded by a variety of criteria c 1 , c 2 , . . . cn . these grading criteria include , in accordance with a preferred embodiment of the invention , the following : alignment , marginal ridges , buccolingual inclination , overjet , occlusal relationship , occlusal contact and interproximal contacts . reference is made to the explanation above of these criteria . the grading , as pointed out above , is based on the deviation of the teeth arrangement from a standard or ideal arrangement , in accordance with one or more of established standards . an example of a standard which may be applied is that set by the american board of orthdontics , referenced above . it should , however , be noted that in some embodiments only part of the above criteria or at times even one , e . g . only the criteria of alignment , may be used to grade the teeth arrangement . in a typical embodiment of the invention , the grading is carried out automatically , although optionally , the grading may be manually done by the user . following the grading according to one or more of the above criteria , at a next step 32 an overall model analysis is carried out . in this analysis the different grading scores are combined , which combination may be a simple combination , may be a weighted combination ( ascribing a different way to a different criteria ) or any other acceptable analysis of the system . here again , the overall model analysis is typically automatic , although it is possible also to permit the user to do it manually . following this overall analysis , at a distant point 34 an assessment is made whether the model meets orthodontic standards or whether an improvement is required . if no improvement is required , the virtual treatment ends 36 . if a decision is made and an improvement is required , which decision may be automatic or may be a decision made by the user , a next step 38 teeth for repositioning are selected , then at 40 the orthodontic appliances are virtually detached from at least the selected teeth , the detached appliances are then repositioned at 42 , to yield repositioning of the teeth . for example , where a bracket is repositioned to a different lateral portion of the tooth , it causes axial rotation of the tooth . where , by another example the bracket is repositioned to a different vertical position of the tooth crown , it causes extraction or retraction of the tooth . where , by a further example , the attachment of the bracket to the wire is the different anteoposterior point on the wire , it causes the tooth to move in the anterior or posterior direction . it should be noted that optionally in steps 40 and 42 , orthodontic appliances are at least temporary removed or hidden for easier visualization of the manipulation outcome . then , at 44 , the detached orthodontic appliances are reassociated to the teeth and a resulting altered treatment state is obtained . the appliances repositioning may be done using an optimization algorithm employing one of many optimization or goal - seeking algorithms where the variable set is the set of appliances positions and the goal is best grade . possible algorithms include deepest descent , newton - raphson method and others . in addition , the goal may also include additional restrictions such as having minimal angle between teeth to avoid results that may give a goal grade but are less aesthetically appealing . the resulting altered treatment state so obtained is analyzed and graded in the same manner as described above . typically in the orthodontic treatment , each tooth is assembled with its corresponding bracket such that the base point of the bracket falls initially on the facial axis point of the tooth , as typically done in orthodontry . the assembled teeth may then translocate along the wire &# 39 ; s curve according to the following criteria : ( i ) the two central incisors are translocated along the wire curve ( along the curve falling on the andrews plane ) until they are brought into at least one point of contact , preferably such that their contact point falls on the mid - platal plane . ( ii ) the lateral incisors on each side of the mid - platal ( the left and right lateral incisors ) may be translocated towards their respective central incisors ( i . e . the left and right incisors , respectively ), followed by translocating the canine , premolar ( first premolar , then premolar ) and molar ( for the first molar , then second molar and optionally then the third molar ) teeth such that each flanking teeth have at least one point of contact therebetween . it should be clear that the same procedure is applied whenever a tooth is extracted or stripped , taking into consideration which tooth exactly was extracted . the outcome of the above procedure is an arch wire set with brackets which are fixed with the respective tooth , the teeth being optimally arranged according to orthodontic criteria . at times , movement of the first molar teeth by the system of the invention may result in a distilization of the mandibular molar teeth in an amount greater than that allowed in a real life treatment according to real life treatment considerations . accordingly , after translocation of teeth as described above , the system verifies whether the mandibular distilization performed would be allowed in real life considerations and if in the negative , the result displayed on the display screen , will show the user that the procedure performed would not be feasible in the real life orthodontic treatment . the user will then know that the orthodontic treatment plan he selected should be changed , e . g . by selecting a different wire , different brackets , performing other , if any manipulations on the teeth , etc . the resulting arrangement of the teeth may further be processed by applying a vertical repositioning of the teeth , and if necessary , move in a manner similar to that in step ( ii ) above . the result obtained for one arch , i . e . the maxillary arch or the mandibular arch , is then used for determination of the inter arch relationship . the algorithm employed may also use some optimization criteria for obtaining the initial treatment stage . for example , the mandibular arch may be first aligned with the mandibular jaw by their central point ( an average distance between the central incisors ) to fall onto the mid palatal plane . the maxillary arch fixed onto the maxillary jaw may then be vertically aligned onto the mandibular jaw in the manner as described in pct publication no . wo 98 / 52493 . the alignment between the two jaws may be according to a fixed mandibular jaw or alternatively according to a fixed maxillary jaw . the following description refers to alignment of the maxilla according to the fixed mandibular jaw . however , it should be understood that the same steps apply in flow diagram , for alignment of the mandible according to the fixed maxilla jaw ( muatis mutandis ). for determining the inter arch relationship , first the parameters of the mandibular jaw are provided , with which the mandibular arch is aligned by determining their center antheroposterior point ( lower center point a - p56 ). then occlusion of the mandibular first molar with the maxillary first molar is dictated by the features of class ( i ) type of occlusion . if necessary , i . e . when the outcome obtained and displayed on the display screen is not the desired outcome or when the user decides it is required to change the class type , he may change the class by which the mandibular first molar and the maxillary first molar interlock until reaching the desired outcome . at times , the horizontal alignment performed will result in a mandibular distilization which is greater than that acceptable in real life orthodontic treatment . as a result , the procedure according to the invention may be carried out while each arch is positioned onto their respective jaw by defining their center antheroposterior point , the steps of interlocking the molar teeth according to standard orthodontic guidelines is not performed . the definition of the different classes which can be selected by the user in a manner as shown herein in fig3 , which shows an example of a screen display showing a virtual model 100 with an upper jaw 102 and a lower jaw 103 . shown in this view is also a view control window 105 which permits control of position of orientation as well as view angles in a manner as described in pct application , publication no . wo 98 / 53428 . the treatment parameters may be controlled through user interface window 106 . a front view of the same jaw is seen in fig4 . fig3 and 4 also show a virtual diagnostic setup model of an individual &# 39 ; s jaws , in its original , untreated form . once an orthodontic treatment is executed , a second three dimensional digital model is obtained . the second three dimensional digital model includes the jaw carrying teeth assembled with brackets and a wire . the teeth in the second model are arranged in an optimal dental and skeletal arrangement as obtained by the system of the invention . the teeth are automatically associated with brackets , the later set on a wire . the outcome of virtual treatment of the original model ( shown in fig3 and 4 ) is seen in fig5 and 6 . in this case the parameters of the system were automatically selected , including the arch wire ( rothoformiii - ovoid ), the brackets ( clarity ™), and class ( class i ) and yielded one optimal outcome . there are different classes which may be applied . class 1 , which is a default class in the system and is that applied in fig5 and 6 . change in the class may be achieved by ticking off box 120 in user interface window 106 and moving scroll bar 122 to either side . another parameter which may be selected is a lower center point , which may be automatically selected ( the automatic selection is dictated by the original center point in the individual &# 39 ; s jaw before treatment ), as in fig3 - 6 or , it may be moved between the interior posterior direction by ticking off box 124 and moving scroll bar 126 to either the left , as seen in fig7 or the right directions . in addition , the arch wire selection may be automatic , as in fig6 and 7 , which in this case is the default arch wire known as ortho form11 - ovoid , but may also be manually selected within selection window 130 . the user may also control the parameters of which jaw will be fixed during the procedure . this is achieved by ticking in the set up design user interface 140 between the mandible 142 selection point or the maxilla 144 selection point . in the case of fig8 , the parameters of maxillary jaw are fixed during the procedure and after aligning therewith the maxillary arch , the inter arch arrangement is performed . by the default of the system , the mandible parameters are fixed and the maxilla is moved accordingly . the reverse selection is shown in fig9 ( 145 ). thus , as can be seen , in view of the initial structure of the teeth , the two jaws are more forwardly oriented in fig9 as compared to fig8 . another manner of control is a virtual extraction of teeth . in fig1 , the treatment is preceded normally without extraction . by ticking alleviation box 138 and marking in the user interface window 106 the tooth or teeth to be extracted , the marked tooth , in this particular case , the second molar 148 is virtually extracted and the void 150 which is left is at least partially filled by lateral movement of the flanking teeth , as seen in fig1 . this feature of the system of the invention enables the user to decide whether extraction of a tooth in a real life treatment will be effective in achieving a desired orthodontic outcome before performing such an irreversible manipulation in the real life treatment . reference is made now to fig2 which shows the manner of using the results of the virtual orthodontic treatment for guidance for the real - life orthodontic treatment . following start 50 , the virtual model with the altered treatment state obtained through the virtual orthodontic treatment ( 36 in fig1 ) is inputted at 52 . the teeth are then , at 54 , permitted to reposition to their original position in the original diagnostic setup model with the orthodontic appliances remaining attached thereon . the association of the orthodontic appliances with the teeth is then recorded as 56 and this is served as an input for guidance of the real - life orthodontic treatment for the purpose of achieving results similar to those obtained in the virtual treatment in accordance with the invention . the manner of association of the orthodontic appliances may be displayed on the screen or may be outputted to a guidance system for proper placing of an orthodontic element on a tooth &# 39 ; s surface , such as that described in u . s . pat . no . 6 , 334 , 772 . | Is 'Human Necessities' the correct technical category for the patent? | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | 0.25 | 576bf4aeb07311d8685f24ee0706a4b030ceb0e451ccd905f07c937433e324c9 | 0.005371 | 0.090332 | 0.000534 | 0.061768 | 0.002625 | 0.092773 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Human Necessities'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.037842 | 0.015869 | 0.003601 | 0.000418 | 0.054199 | 0.02063 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Is 'Physics' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.051758 | 0.043945 | 0.017456 | 0.010681 | 0.078125 | 0.075684 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Does the content of this patent fall under the category of 'Physics'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.054932 | 0.002808 | 0.003372 | 0.000029 | 0.086426 | 0.004333 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Is this patent appropriately categorized as 'Physics'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.091309 | 0.005371 | 0.024414 | 0.000336 | 0.108398 | 0.037842 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.051758 | 0.038574 | 0.017456 | 0.115723 | 0.078125 | 0.042725 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.051758 | 0.002975 | 0.017456 | 0.000357 | 0.078125 | 0.008606 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Should this patent be classified under 'Physics'? | Is this patent appropriately categorized as 'Electricity'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.037842 | 0.207031 | 0.003601 | 0.018311 | 0.054199 | 0.15332 |
null | in the following , a particular embodiment of the invention will be described by way of example only . fig1 is a perspective view of a system unit 10 for use in a rack - mountable system . in a particular example described herein , the system unit is a computer system unit for forming a computer server for a telecommunications application , for example an internet server . as shown in fig1 the unit 10 has a front surface 12 formed by a front wall , a rear surface 14 formed by a rear wall , a left end surface 16 formed by a left side wall , a right end surface 18 formed by a right side wall , a lower surface 20 formed by a base wall and an upper surface 22 , in the present example formed by a cover 30 . as shown in fig1 the system unit 10 is provided with sacrificial transport flanges 24 , which extend above and below the system unit . this optional feature is removed before installation of the system unit 10 in a rack . the system unit 10 is constructed with an extremely robust chassis 11 , with the various walls 12 - 20 and the cover 30 forming the casing of the chassis 11 as well as internal walls ( not shown ) being formed of heavy gauge steel . the walls of the chassis can be made , for example , from electroless nickel - plated mild steel with a thickness of , for example , 1 . 5 to 2 . 0 - mm . the steel chassis 11 is pre - formed with mounting holes for the attachment of mounting flanges or a slide mechanism to enable the system unit 10 to be provided with a wide variety of mounting options and rack sizes . mounting flanges can be provided to suit standard 19 - inch , 23 - inch , 24 - inch or 600 - mm nominal frame widths . ( one inch = approximately 25 . 4 mm ). fig2 a is a plan view of the unit 10 showing the upper surface 22 / cover 30 and various options for flanges 26 with the displacements from the front surface indicated in mm . fig2 b is a front view of the unit 10 showing the front surface 12 and two different examples of mounting flanges 26 . the mounting flange shown to the left ( as seen in fig2 b ) is provided with a handle to facilitate insertion and removal of the unit 10 from the racking system , whereas the flange 26 to the right ( as viewed in fig2 b ) is not provided with a handle . in the present example , the mounting flanges can be attached using screws which pass through the mounting flange into threaded holes in the end walls 14 , 16 at either side of the chassis 11 of the unit 10 . fig2 c is a side view of the system unit 10 , showing the holes in the side of the system unit 10 for the mounting of flanges or a slide mechanism . vertical rows of holes are for the attachment of flanges to be attached to vertical rack components , and horizontal rows of holes provide for the attachment of a runners for permitting a slideable mounting of the system unit in a rack . fig3 is a perspective rear view of the unit 10 showing the cover 30 that forms the top surface 22 of the unit 10 as can be seen , the cover 30 is provided with front locating flanges 32 that , in use , engage a co - operating front flange 31 of the body of the chassis 11 . side flanges 33 engage either side of the end walls forming the left and right ends 16 and 18 of the chassis 11 . detents 34 on those end walls engage within l - shaped slots 35 in the side flanges 33 so that the cover may be lowered onto the top of the chassis 11 and then moved forwards so as to cause the detents 34 to latch within the slots 35 . at the rear of the cover 30 , a rear flange 36 with a lower lip 37 engages over an abutment 38 at the top of the rear end wall 14 of the casing 10 . the cover can be secured to the remainder of the chassis 11 by means of a screw 39 that passes through this rear flange into a threaded hole in the abutment 38 . fig4 is an exploded perspective view from the front of the system unit 10 . this shows a motherboard 40 that is mounted on a horizontal mounting plane 41 within the chassis 11 . mounted on the motherboard 40 are between one and four processor modules 42 . a riser card 44 can receive a plurality of dual in - line memory modules ( dimms ) 46 . further dimms 46 can be received directly in slots in the motherboard . a slideable carriage 48 is provided for receiving one or more media drives . as shown in fig4 the slideable carriage 48 can receive up to two media drives . in the present instance , two media drives including a digital audio tape ( dat ) drive 50 and a cd - rom drive 52 are provided . appropriately configured metal cover plates 54 and 56 are provided for the media drives 50 and 52 . a disc bay assembly 58 provides a small computer system interface ( scsi ) backplane and cables for receiving one or more scsi media drives , such as a scsi disc drive 60 . although , in the present instance , the drives are controlled via a scsi - type interface , it will be appreciated that another media drive interface ( e . g ., ide ) could be used . a scsi card ( not shown ) is located within the chassis to the front of the motherboard . a bezel ( decor panel ) 62 is provided for covering ventilation holes 63 in the front wall 12 of the chassis 11 . a bezel 64 is provided for covering the media drives 50 , 52 and 60 . a fan control module 66 controls the operation of processor fans 68 and system fans 70 . a power sub - assembly that includes a power sub - frame 72 with a power distribution board assembly , is provided for receiving three separate power supply units 74 . an alarms module in the form of an alarms card 78 enables the signalling of alarms to the outside world , and is also connected to an led card 2 for signalling alarms locally on the front of the unit 10 . a power switch 82 is also provided on the front surface of the unit 10 . fig4 also illustrates one pci card 84 to be received within a pci slot 85 on the motherboard 40 . fig5 is a front view of the unit 10 showing the bezels 62 and 64 , a power and alarm panel 90 which includes the power switch 82 and a number of status light emitting diodes ( leds ) 92 . fig5 also illustrates the slots 86 and 88 for the media drives such as media drives 50 and 52 shown in fig4 . fig6 is a rear view of the unit 10 in a configuration with three dc power supply units 74 a , 74 b and 74 c . each of the power supply units 74 a , 74 b and 74 c is the same , and provides redundant power for the unit 10 . however , as will be seen later , one or more of the dc power supply units could be replaced by ac ( mains ) power supply units . the power supplies are hot swappable ( i . e ., while the system is running ), as long as they are swapped one at a time . with regard to power supply unit 74 a , it can be seen that this is provided with a handle 94 that is used for inserting and removing the power supply unit 74 a . the handle 94 includes a flange portion that is able to receive a screw 95 for securing the power supply unit to the chassis 11 . first and second power cable sockets 96 and 98 are shown . also shown is a grounding plate 100 that is secured by knurled nuts 102 , 104 and 106 to grounding studs 103 , 105 and 107 . grounding stud 103 provides a connection directly to the chassis 11 of the unit 10 . grounding studs 105 and 107 , on the other hand are electrically isolated from the chassis by an insulating board and are instead connected to logic ground ( i . e . the ground of the electronic circuitry ). by means of the grounding plate 100 , logic ground can be connected directly to chassis ground . the provision of this grounding plate provides for optional tying of logic ground to chassis ground . it will be noted that each of the power supply units 74 is provided with a similar grounding plate 100 , for connection to corresponding grounding studs . if it is desired to isolate logic ground from chassis ground , it is necessary to remove the grounding plate 100 from each of the power supply units 74 a , 74 b and 74 c . an isolated ground system is needed in some telco applications when operating in a regional bell operating company ( rboc ) mode . when operating in such a mode , the chassis and logic ground are connected at a remote location to provide , for example , lightning protection . in this case two - hole lugs 101 having a pair of holes 111 to fit over the pair of grounding studs 105 and 107 are provided for each of the power supply units 74 and are secured over the studs using nuts 104 and 106 . a similar two - hole lug 101 is secured to the grounding studs 108 and is secured with similar nuts . earthing wires 109 from each of the two - hole lugs 101 on the power units and the chassis then are taken to the remote , earthing location . the studs 103 105 , 107 and 108 are of a standard thread size ( m 5 ). the studs 105 / 107 and the studs 108 are at a standard separation ( 15 . 85 mm ). the studs 105 / 107 are selfretaining in the insulated board on the power supply units . the stud 103 is self - retaining in the casing of its power supply unit 74 . the suds 108 are also self - retaining in the system unit chassis . in a non - isolated ground situation , chassis ground can simply be tied to a desired ground potential ( for example , to the racking system ) by connecting a grounding cable to grounding studs 108 provided on the rear of the chassis . a further earth connection is provided via the power cables for the power supplies . fig6 also illustrates rear ventilation holes 110 through which air is vented from the system . fig6 also shows the alarms module 78 with a serial connector 112 enabling connection of the alarms module to a network for the communication of faults and / or for diagnostic operations on the unit 10 to be performed from a remote location . fig6 also shows a number of pci cards 84 received within respective pci slots 116 . a number of further external connections 114 are provided for connection of serial connections , parallel connections and scsi connections , and for the connection of a keyboard or a twisted - pair ethernet ( tpe ) connector . fig7 is a plan view of the motherboard 40 shown in fig4 . four cpu module slots 120 are provided . each of these slots is able to receive one processor module 42 , and any number between one and four slots may be occupied by a processor module 42 . a connector arrangement 122 is provided for receiving a riser card 44 as shown in fig4 . also , connectors 124 ( in four banks ) are provided for receiving dimms 46 as mentioned with reference to fig4 . edge connectors 126 are provided for connecting the motherboard to connectors mounted on the mounting plane 41 . also shown in fig7 is the slot 128 for the alarms module 78 and various ports 130 for the connectors 114 shown in fig6 . fig8 is a schematic overview of the computer architecture of the system 10 . as shown in fig8 various components within the system are implemented through application - specific integrated circuits ( asics ). the system is based round a ultrasparc port architecture ( upa ) bus system that uses a peripheral component interconnect ( pci ) protocol for an i / o expansion bus . the cpu modules 40 . 0 , 40 . 1 , 40 . 2 , 40 . 3 , and a upa - to - pci ( u 2 p ) asic 154 communicate with each other using the upa protocol . the cpu modules 40 and the u 2 p asic 154 are configured as upa master - slave devices . an address router ( ar ) asic 154 routes upa request packets through the upa address bus and controls the flow of data to and from memory 150 using a data router ( dr ) asic 144 and a switching network 148 . the ar asic 154 provides system control . it controls the upa interconnect between the major system components and main memory . the dr asic 144 is a buffered memory crossbar device that acts as a bridge between six system unit buses . the six system unit buses include two processor buses , a memory data bus and to i / o buses . the dr asic 144 provides crossbar functions , memory port decoupling , burst transfer and first - in - first - out ( fifo ) data read functions . clock control for the operation of the processor is provided by a reset , interrupt , scan and clock ( risc ) asic 152 . the pci bus is a high performance 32 - bit or 64 - bit bus with multiplexed address and data lines . the pci bus provides electrical interconnection between highly integrated peripheral controller components , peripheral add - on devices , and the processor - memory system . a one - slot pci bus 155 connects to a pci device 156 . 0 . a three - slot pci bus connects to three pci slots 156 . 1 , 156 . 2 and 156 . 3 . two controllers are also connected to the second pci bus 157 . these include a scsi controller 174 and a pci - t 0 - ebus / ethernet controller ( pcio ) 158 . the scsi controller 174 provides electrical connection between the motherboard and separate internal and external scsi buses . the controller also provides for scsi bus control . the pcio 158 connects the pci bus to the ebus . this enables communication between the pci bus and all miscellaneous i / o functions as well as the connection to slower , on board functions . thus , the pcio enables the connection to an ethernet connection via a transmit / receive ( tx / rx ) module 161 and a network device ( nd ) module 162 an ebus 2 159 provides a connection to various i / o devices and internal components . super i / o 164 is a commercial off - the - shelf component that contains two serial port controllers for keyboard and mouse , an ieee 1284 parallel port interface and an ide disk interface . the super i / o drives the various ports directly with some electromagnetic interference filtering on the keyboard and parallel port signals . the alarms module 78 interfaces with the motherboard and provides various alarm functions . the nvram / tod 168 provides non - volatile read only memory and the time of day function . serial port 170 provides a variety of functions . modem connection to the serial port 170 enables access to the internet . synchronous x . 25 modems can be used for telecommunications in europe . an ascii text window is accessible through the serial port on non - graphics systems . low speed printers , button boxes ( for computer aided design applications ) and devices that function like a mouse are also accessible through the serial port . the serial port includes a serial port controller , line drivers and line receivers . a one - mbyte flash programmable read only memory ( prom ) 172 provides read only memory for the system . fig9 is a perspective rear view of the system 10 showing the withdrawal and / or insertion of a power supply unit 74 in a non - isolated ground situation . in this example , ac power supply units 74 are shown . it can be seen that the power supply unit 74 is provided with the handle 94 . as shown in fig9 the handle 94 is provided with a grip 184 , a pivot 182 and a latch 180 . to insert the power supply unit 74 it is necessary to slide the power supply unit into the power sub - frame 72 with the grip 184 of the handle 94 slightly raised so that the detent 180 can be received under the top 184 of the power sub - frame 72 . as the power supply unit 74 reaches the end of its movement into the power sub - frame 72 , connectors ( not shown ) provided on the power supply unit 74 make connection with a corresponding connector on the power distribution board at the rear of the power sub - frame 72 . also , at this time , the handle can be pushed down into the position shown in fig9 . this causes the detent 180 to latch behind the upper portion 184 of the power sub - frame 72 . the handle 94 can then be secured in place by tightening the screw 95 . the ac power supply unit 74 shown in fig9 has a single power socket 97 , whereas the dc power supply units 74 shown in fig6 have two power sockets 96 and 98 . irrespective of whether the arrangement is as shown in fig6 with two dc power sockets 96 and 98 , or as shown in fig9 with one ac power socket 97 , the configuration of the power socket ( s ) and the lever 94 is such that the lever cannot be moved , and therefore the power supply unit cannot be released from the power sub - frame 72 and the chassis 11 with a plug 186 of a power cable 188 in place in one of the power sockets 96 / 97 / 98 . the removal operation is achieved by releasing the screw 95 , removing the power plug , and lifting and pulling on the handle 94 . in an isolated ground situation , in order to hot - swap a power supply unit 74 , it is merely necessary to remove the two - hole lug 101 with its connecting earth wire 109 from the studs 105 , 107 of the power supply unit to be removed , to remove the old power supply unit 74 , to replace a new power supply unit 74 and then to reconnect the two - hole lug 101 and connecting earth wire 109 to the studs 105 , 107 of the new power supply unit 74 . these operations can all be performed with the system under power from the other power supply units 74 and with the two - hole lugs 101 and earth wires 109 in place over the chassis studs 108 and the studs 105 , 107 of the other power supply units 74 . the isolated ground situation is not shown in fig6 and 9 . in the non - isolated ground situation shown in fig6 and 9 , hot - swapping of a power supply unit is even easier , as it is merely necessary to remove the selected power supply unit 74 and to replace it with the new power supply unit 74 . fig1 a , 10 b , 10 c and 10 d are rear , top , front and perspective views of a power sub - frame for receiving three power supply units : the power sub - frame 72 comprises a rectangular , box - shaped frame 191 , with four exterior walls on four sides ( the top , bottom and two lateral surfaces ), one open side 195 for receiving three power supply units and a power distribution circuit board 190 opposite to the open side . in the present instance , the walls are made of electroless nickel - plated mild steel . fig1 a shows the power distribution board at the “ rear ” of the power sub - frame ( i . e . opposite to the open side ). when inserted in the chassis of the system unit , this “ rear ” of the power sub - frame is actually the forward - most side of the power sub - frame when viewed with respect to the system unit . the power distribution board 190 is formed with ventilation holes 194 and carries circuit tracks and components ( not shown ). fig1 a also illustrates the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 b shows the top of power sub - frame . it will be noted that the power sub - frame body 196 is provided with apertures 197 for lightness and for ventilation purposes . fig1 c shows the open ( front ) side 195 ( see fig1 b ) of the power sub - frame . when inserted in the chassis of the system unit , this “ front ” of the power sub - frame is actually the rear - most side of the power sub - frame when viewed with respect to the system unit . within the power sub - frame 72 , connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c , respectively , can be seen . these connectors are mounted on the power distribution board 190 inside the power sub - frame 72 . fig1 c also shows the flanges 198 with screw holes 199 for securing the power sub - frame to the rear chassis wall . fig1 d is a perspective view of the power sub - frame 72 , which shows that this in fact forms part of a power sub - assembly 71 . internal walls 200 separate three compartments , each for a respective one of the three power supply units 74 . cables 202 connect standby power and signal lines from the power distribution board 190 to a connector 204 for connection to an alarms module . cables 206 connect main power and signal lines from the power distribution board 190 to various connectors 208 , 210 , 212 and 214 . fig1 e shows the various connector types 192 , 204 , 208 , 210 , 212 and 214 and the electrical signal connections thereto . fig1 is a schematic representation of some of the logic connections on the power distribution board . for ease of explanation , only those connections relevant for an understanding of the present invention are described . at the left of fig1 , the three connectors 192 a , 192 b and 192 c for the three power supply units 74 a , 74 b and 74 c are shown . for reasons of clarity and convenience only those connections relevant for an understanding of the present invention as shown . for example , as illustrated with respect to fig1 e , the connectors 192 have many pins and pass many signals via respective lines . however , as not all of these lines are necessary for an understanding of the present invention , and as it would be confusing to illustrate all of the signal pathways on a diagram , only selected pathways are shown in fig1 . it is to be noted from fig1 e , that the power supply units output ground , + 3v 3 ,+ 5v , + 12v , − 12v and + 5v standby potentials as well as control signals such as psu ok , psu on , etc . the + 5v standby voltage is used for powering the alarm module 78 . the other voltages are for powering the motherboard and other main system components . the various lines could be configured using bus bars , wires , printed circuit or thick film conductors as appropriate . firstly , the two - of - three circuit 232 will be explained . this circuit is powered by the + 5v standby voltage 231 provided from each of the power supply units 74 . each of the power supply units outputs a psu ok signal via a pin on its respective connector to a corresponding psu ok line 230 a , 230 b and 230 c when the power supply unit is operating correctly . each of these psu ok lines 230 is connected to the two - of - three circuit 232 . this comprises three and gates 234 , 236 and 238 , each for comparing a respective pair of the psu ok signals . the outputs of the and gates are supplied to an or gate 240 . if the output of this or gate is true , then at least two of the power supply units 74 are operating correctly , and power can be supplied to the motherboard of the computer system . this can be achieved by closing the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to enable current to pass to the motherboard and other system components . additionally , or alternatively , a power ok signal 246 for controlling some other form of switch mechanism ( not shown ). if alternatively the output of the or gate 242 is false , then this indicates less than two of the power supply units 74 are operative . in this case power is prevented from being passed to the motherboard 40 of the computer system . this can be achieved by interrupting the main power line 245 . an output signal 242 could be supplied to a gate 244 ( for example a power fet ) to prevent current being passed to the motherboard and other system components . additionally , or alternatively , a power fault signal 246 could be passed to the alarms module and / or for controlling some other form of switch mechanism ( not shown ). one - of - three power control is effectively provided by the alarms module 78 to be described later . however , with reference to fig1 , input a / b signals 268 and output sense signals 270 are passed to the alarms module for standby operation , and control signals 272 could be returned for turning off of a power supply unit , if required . fig1 further illustrates a protection circuit 256 that is able to detect an overcurrent representative of a current greater than 2 * imax , where imax is the maximum current that can be output by a power supply , 2 * imax being the maximum current which should be required by the system unit . if a current greater than 2 * imax is detected , this is representative of a fault in the system unit . in accordance with telco requirements , in such a situation the system should be powered down . by providing for overcurrent detection on the power distribution board , where the maximum drawable current should be 2 * imax , it is possible to test for a fault at a lower overall current than if this test were made within each power supply unit . if the test were made in each power supply unit , each power supply unit would need to be tested for an overcurrent in excess of imax , whereby one would be testing for a total current drain of 3 * imax . this could lead to faults not being detected or not detected early enough and the system could incorrectly be drawing up to 3 * imax , which could damage components and traces ( tracks ). thus , as shown in fig1 , each of the main power lines ( e . g ., + 12v ) 250 a , 250 b and 250 c from the power supply units 74 a , 74 b and 74 c , respectively is connected to form a common power supply line 254 . an overcurrent detector 258 detects a current in excess of 2 * imax . if such a current is detected ( for example as a result of a fault represented by the box 266 ), then a signal 261 is provided to the connectors 192 , a , 192 b and 192 c for shutting down the power supplies 74 a , 74 b and 74 c , respectively . also , a signal 262 is passed to a switchable shunt 260 ( e . g ., a silicon controlled rectifier ( scr ), a metal oxide semiconductor field effect transistor ( mosfet ), an insulated gate bipolar transistor ( igbp ), etc ) to shunt the power supply line 254 to ground . this will cause any energy stored in the power supplies and also in the system ( for example as represented by the capacitor 264 ) to drain to ground , thus protecting the system . the use of the two - of - three circuit described above means that redundant power supply operation is provided in that the system can remain powered even if one of the three power supply units fails . as only two - of - three power supply units are needed to power the system the third power supply unit can be hot swapped while the other two power supply units power the system . fig1 illustrates the location of an alarms card forming the alarms module 78 in the rear of the system unit 10 . fig1 is a functional block diagram for illustrating the alarm sub - system on the alarms module 78 . the alarms sub - system provides lights out management or remote management of the system over a serial connection . the alarms module 78 interfaces with the motherboard through an ebus edge connector slot 298 ( connected to ebus2 as shown in fig8 ). a pci - style bracket is attached to one edge of the alarms module ( as seen in fig1 ) and provides the external interfaces at the rear of the chassis 11 . internal interfaces provide connections to the power supply assembly and to the led card 80 located at the front panel of the system unit 10 . the alarms module is powered by the standby , or reserve , power supply . the alarms module only requires power from a single power supply to remain operable . accordingly , the alarms module can remain operable even in a situation where the system has been powered down due to there being only one power supply unit operable . the alarms sub - system comprises a logic device 280 which receives inputs 298 from the ebus , inputs 286 from the fans , input 290 from general purpose events , input 270 from the power supply unit output rails and inputs 268 from the a and b power inlets . the logic circuit samples , or multiplexes , the inputs to the microcontroller 296 in response to multiplex signals from the microcontroller 296 . the microcontroller 296 processes the sampled ( multiplexed ) inputs . the microcontroller 296 provides power control signals 272 for controlling the power supply units , and alarm outputs for the output of alarm signals . the microcontroller 296 also outputs power supply unit status signals 304 and fault signals 306 . the micro controller 296 can further output a system reset signal 310 , when required . alarm signals to be passed to a remote location can pass via a remote serial connection 112 . diagnostic and remote control signals can be passed from the network via the serial connection 112 to the microcontroller 296 . control signals can thus be provided via the remote serial connection over the network for powering on and powering off the system . examples of other commands that can be sent to the microcontroller via the remote serial connection 112 are to turn alarms off , to reset the monitoring of all failures , to display the status of all fans , power supply units , alarms and fault light emitting diodes ( leds ), to display an event log , etc . the microcontroller is programmed to report any fan failures or changes in power supply units status by means of the leds 92 ( fig5 ) on the system front and optionally to report the faults via the remote serial connection 112 . the microcontroller 296 is programmed to maintain the event log that was referenced above . fig1 illustrates the configuration of the fan control module 66 shown in fig4 . the fan control module is subdivided into two halves 66 a and 66 b . one half 66 a handles one processor fan 68 a and one system fan 70 b and the other half 66 b handles the other processor fan 68 band the other system fan 70 b . the fans are connected to the fan control module 66 by respective power lines 320 so that the fans receive their power via the fan control module . the fan control module receives + 12v power via power lines 324 a / b from the power distribution board 190 and supplies voltages to the fans via the power lines 320 in a controlled manner . for convenience , tacho ( speed ) signals from the fans pass via the alarms control module 66 . the speed signals are not processed by the fan control module , but are instead forwarded via tacho sense 326 to the power distribution board 190 . the power distribution board then routes the tacho sense signals to the alarms module 78 to form the signals 286 shown in fig1 . this routing is convenient as it enables simpler wiring looms to be used . also , when replacing a fan unit , the maintenance engineer only needs to remove a single bundle of wires from the fan to the fan control module 66 , rather than having to locate a number of different connectors connected to the fan . the fan control module thus has four fan connectors , each for receiving a connector connected to a bundle of wiring from a respective fan , plus a further connector for receiving a connector with a bundle of wires from the power distribution board . as shown in fig1 , each half 66 a / 66 b of the fan control module receives respective power lines 324 a / b from the power distribution board . each half of the fan control module includes electrical noise isolation circuitry 340 a / b . this electrical noise isolation circuitry 325 a / b , which can be of conventional construction , prevents dirty power signals on the lines 320 a / b caused by electrical noise from the fans being passed back along the power lines 324 a / b and potentially contaminating the otherwise clean power supply to the electronics of the system unit ( e . g ., the components on the scsi bus . the provision of clean power supply signals in a telco application is important in order to ensure reliability of operation . although in the present example the noise isolation circuitry is located in the fan control module , it could be located elsewhere as long as it is effective to isolate the main power lines from fan - related electrical noise . as further shown in fig1 , each side 66 a / b of the fan control module comprises control logic 342 a / b which receives a temperature signal from a temperature sensor 344 and adjusts the speed of the fans by adjusting the voltage supplied thereto in accordance with pre - programmed parameters in order to provide a desired degree of cooling . the control logic 342 a / b can be implemented by an asic , a programmable logic array , or any other appropriate programmable logic . alternatively , it could be implemented by software running on a microcontroller or microprocessor module . it should be noted that the fan control module could be implemented in a unitary manner , rather than being divided into two halves . although in the present instance the fan control module is preferably configured on a single circuit board , this need not be the case . also , although the temperature sensor is also mounted on the same circuit board , it could be mounted elsewhere . moreover , although it is preferred that a single temperature sensor is used , with the advantage that the fan speeds of the respective fans can be ramped up in parallel in a controlled manner , more than one temperature sensor could be used . ideally , in this case they would be located close together and control of the individual fans could be dependent on individual signals but would more preferably be dependent on a function of some or all of the temperature signals . as a further feature , the control logic could be provided with different sets of programmed parameters depending on the number of processors present and could be responsive to the number of processors present . it will be appreciated that although particular embodiments of the invention have been described , many modifications / additions and / or substitutions may be made within the spirit and scope of the present invention . accordingly , the particular example described is intended to be illustrative only , and not limitative . | Is this patent appropriately categorized as 'Physics'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 9f13ad2b535bc3f9cbd17c0d24feca49767f2fb3fc7015227cc7e95062b589dc | 0.095215 | 0.120117 | 0.024414 | 0.061035 | 0.108398 | 0.121094 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.306641 | 0.014526 | 0.402344 | 0.00383 | 0.326172 | 0.003708 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | Is 'Performing Operations; Transporting' the correct technical category for the patent? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.143555 | 0.017944 | 0.198242 | 0.017456 | 0.239258 | 0.078125 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Is 'Textiles; Paper' the correct technical category for the patent? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.306641 | 0.000296 | 0.402344 | 0.000021 | 0.326172 | 0.005371 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.361328 | 0.019775 | 0.617188 | 0.010986 | 0.419922 | 0.049561 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.142578 | 0.022583 | 0.198242 | 0.000881 | 0.239258 | 0.098145 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Does the content of this patent fall under the category of 'Physics'? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.306641 | 0.138672 | 0.402344 | 0.03064 | 0.326172 | 0.263672 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Is 'Electricity' the correct technical category for the patent? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.306641 | 0.000732 | 0.402344 | 0.000854 | 0.326172 | 0.001137 |
null | the process of the present invention for facilely producing ( 2r - trans )- n -( 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ] quinolizine - 2 , 4 &# 39 ;- imidozalidin ]- 3 &# 39 ;- yl ) ethyl ) methanesulfonamide ( i ) comprises the following sequence of reactions : 1 ) intimately contacting ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - aro [ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride ( compound b • 2hcl ) with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain a novel intermediate , ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 - 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile ( compound d ); 2 ) intimately contacting ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methanesulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - aro [ 2 , 3 - a ] quino - lizine - 2 - carbontrile with hydrogen in the presence of raney nickel catalyst and sodium methoxide to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - aro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin )- 3 &# 39 ;- yl ) ethylmethanesulfonamide and then contacting said methanesulfonamide with methanol and acetyl chloride to obtain the monohydrochloride thereof ( compound i • hcl ). the foregoing steps may be illustrated in the following flow diagram : ## str9 ## ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - aro -[ 2 , 3 - a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , compound b . 2hcl , which is the starting material for the sequence of reactions which constitute the present invention may be obtained by bringing alcoholic hydrogen chloride into intimate contact with compound b ( free base ) prepared as subsequently outlined and more fully described in the aforementioned copending application u . s . ser . no . 76 , 495 and south african patent 87 / 6400 , the teachings of which are incorporated by reference . the crystalline hydrochloride salt which forms may be recovered by filtration , washed and dried in a conventional way . in the process of the present invention , the first step of reacting compound b as the bis - hydrochloride with carbonyldiimidazole is carried out by adding compound b . 2hcl to a reaction medium containing carbonyldiimidazole and a hydrogen chloride acceptor in solution in an inert solvent at a temperature in the range of about 15 ° to 50 ° c ., preferably ambient temperature , for up to several hours until the reaction is substantially complete . the completion of the reaction may be determined by liquid chromatography . the carbonyldiimidazole is employed in substantial molar excess . generally , from about three - to five - fold molar excess is satisfactory . a strong base is desired as the hydrogen chloride acceptor . many of the conventional tertiary amines are not completely satisfactory . suitable hydrogen chloride acceptors include 1 , 8 - diazabicyclo -[ 5 . 4 . 0 ] undec - 7 - ene ; 1 , 5 - diazabicyclo [ 4 . 3 . 0 ] non - 5 - ene ; and [ 1 , 8 - bis ( dimethylamino )- naphthalene , n , n , n &# 39 ;, n &# 39 ;- tetramethyl - 1 , 8 - naphthalene ] (&# 34 ; proton sponge &# 34 ;); and other strong bases . imidazole also may be employed but tends to produce lower yields . the reaction is carried out in a solvent . suitable solvents include tetrahydrofuran , dioxane , dimethylformamide , dimethyl sulfoxide , acetonitrile and the like . chlorinated solvents are generally not satisfactory because of the relatively low solubility of the reactant in the chlorinated solvents . after completion of the reaction , the reaction mixture is concentrated under reduced pressure and to the concentrated solution are added a water - immiscible organic solvent and deionized water and the components of the reaction mixture partitioned . the organic product layer is then washed , preferably with brine and then concentrated under reduced pressure to form crystals of compound d in the concentrated mixture . the resulting slurry is flushed into a non polar solvent , cooled and aged to obtain the desired intermediate compound d , a novel compound , as a crystalline solid . the second step of the process of the present invention is carried out by charging a high pressure hydrogenation vessel with raney nickel catalyst , methanol solvent , sodium methoxide and compound d , introducing hydrogen and then maintaining the temperature and pressure at 50 ° c .± 1 ° c . and 40 psig until the reaction is substantially complete . after completion of the hydrogenation , the vessel is cooled to ambient temperature , the catalyst removed and washed , and the filtrates combined and concentrated . methylene chloride and saturated sodium bicarbonate solution are added . after a short ( few minutes ) aging period , the organic and aqueous layers are separated , and the organic layer concentrated to obtain compound i as a slurry . the slurry is washed with methanol , and concentrated . to a separate vessel charged with methanol and acetyl chloride and maintained below about 20 ° c . for in situ generation of hydrogen chloride , is added the methanolie slurry of compound i . the slurry is then aged first at 20 °- 25 ° c . and thereafter at about 0 ° c . to complete the formation of the hydrochloride of compound i . the slurry is then filtered washed and dried to obtain compound i &# 39 ;. hcl product . a compound particularly useful in the treatment of diabetes , ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ] methanesulfonamide , may be produced facilely by this method which as applied to this compound comprises the steps of : ( 1 ) intimately contacting ( 2r , trans )- n -[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3 - a ] quinolizin - 2 - yl ) amino ] ethyl ] methanesulfonamide - bis - hydrochloride with carbonyldiimidazole in the presence of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene to obtain ( trans )- 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ]- 2h - benzofuro [ 2 , 3 - a ]- quinolizine - 2 - carbonitrile ; and ( 2 ) intimately contacting said ( trans )- 1 , 3 , 4 , 5 , 7 , 12b - hexahydro - 2 -[ 3 -( methylsulfonyl )- 2 - oxo - 1 - imidazolidinyl ] 2h - benzofuro [ 2 , 3 - a ] quinolizine - 2 - carbonitrile with hydrogen in the presence of raney nickel catalyst to obtain ( 2r - trans )- n -[ 2 -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2 &# 39 ;- oxospiro [ 2h - benzofuro -[ 2 , 3a ]- quinolizine - 2 , 4 &# 39 ;- imidazolidin ]- 3 &# 39 ;- yl ) ethyl ]- methanesulfonamide and thereafter intimately contacting the methanesulfonamide with a mixture acetyl chloride and methanol to obtain the monohydrochloride salt thereof . the following example illustrates the invention but is not to be construed as limiting . 7 . 5 kg of carbonyldiimidazole was charged to 95 kg of dried tetrahydrofuran and the mixture aged at 25 ± 2 ° c . for 10 minutes . 3 . 6 kg of 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene was pumped thereinto followed by a pump and line rinse with 3 - 5 liters of tetrahydrofuran . 5 . 3 kg of ( 2r - trans )-[ 2 -[( 2 - cyano - 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzofuro [ 2 , 3a ] quinolizine - 2 - yl )- amino ] ethyl ] methanesulfonamide bis - hydrochloride , ( compound b &# 39 ;• bis hcl ) was added as a solid and the mixture aged at about 25 ° c . for two hours to produce compound d &# 39 ; in the reaction mixture . when the reaction is substantially complete as determined by liquid chromatography , the reaction mixture was vacuum concentrated at 35 ° c ./ 50 mm hg to a volume of 10 gallons . to the concentrate was added 240 kg of ethyl acetate and 28 gallons of deionized water and the concentrate partitioned to recover the intermediate compound d &# 39 ; in the organic layer . the organic solution was washed twice with saturated sodium chloride solution and vacuum concentrated at 30 ° c ./ 50 mm hg to 10 gallons . the concentrate was flushed with 300 kg of ethyl acetate to kf = 80 mcg / ml ( karl fischer assay ) and then vacuum concentrated at 30 ° c ./ 50 mm hg to 15 gallons . crystallization of the intermediate ( compound d ) occurred during the flush . the slurry was flushed into 210 kg hexane , vacuum concentrated at 30 ° c ./ 50 mm hg to a final volume of 25 gallons , and then cooled to about 0 ° c ., aged for one hour and then filtered . the filter cake was washed with 14 kg hexane and vacuum dried at 25 ° c . to a loss on drying of less than 0 . 1 percent . the yield of compound d &# 39 ; was 4 . 8 kg or 91 percent of theoretical . 1 h nmr ( cdcl 3 , 300 mhz ) δ 7 . 35 - 7 . 50 ( m , 2h ), 7 . 15 - 7 . 32 ( m , 2h ), 3 . 80 - 3 . 95 ( m , 2h ), 3 . 69 ( dd , j = 11 . 9 , 2 . 1 hz ), 3 . 55 - 3 . 65 ( m , 2h ), 3 . 34 ( s , 3h ), 2 . 55 - 3 . 23 ( m , 8h ) 2 . 14 ( dt , 1h , j = 4 . 5 , 12 . 8 hz ), 1 , 91 ( t , 1h , j = 12 . 8 ). 13 c nmr ( cdcl 3 ) δ 154 . 5 , 154 . 1 , 150 . 6 , 127 . 6 , 123 . 7 , 122 . 6 , 118 . 8 , 117 . 5 , 111 . 7 , 111 . 1 , 55 . 9 , 55 . 1 , 51 . 3 , 50 . 7 , 40 . 8 , 40 . 5 , 40 . 3 , 35 . 6 , 33 . 4 , 20 . 9 . 10 kg of raney nickel catalyst previously dehydrated via methanol decantation was charged to a hydrogenation bomb . thereafter 190 kg methanol was charged via residual vacuum , followed by 1 . 3 kg sodium methoxide and 4 . 8 kg compound d &# 39 ;. the bomb was pressure tested at 50 psig with nitrogen then hydrogen was introduced and hydrogenation was carried out at 50 ± 1 ° c ./ 40 psig until the reaction was complete ( about 5 hours ). the bomb was cooled to 25 ° c ., the catalyst filtered , and the filter cake washed with 75 kg of methanol . the combined filtrate was then vacuum concentrated at 60 ° c ./ 50 mm hg to a volume of 12 gallons . 308 kg of methylene chloride and 63 kg of saturated sodium bicarbonate solution were added to the concentrated , the mixture aged for 5 minutes at 20 °- 25 ° c . and the layers separated . the organic product layer was flushed with 120 kg of methylene chloride to kf = 1 mg / ml and then vacuum concentrated at 25 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was then flushed with 72 kg of methanol and vacuum concentrated at 30 ° c ./ 50 mm hg to a volume of 12 gallons . the concentrate was recovered , the vessel rinsed with 3 to 5 liters of methanol and the rinse separately saved . a separate vessel was charged with 15 kg methanol and 1 . 0 kg of acetyl chloride while maintaining the temperature at less than 20 ° c . for an in situ generation of hydrogen chloride . to the vessel then was charged the methanolic solution of the hydrogenation product followed by a methanol rinse . the resulting slurry was aged at 20 °- 25 ° c . for one - half hour , then cooled to about 0 ° c . and aged for an additional two hours . at the end of this period the slurry was filtered , the filter cake washed with 9 kg methanol and the cake dried at 25 ° c . to a loss on drying of less than 71 %. the yield of the product was 3 . 2 kg or 71 percent . in an operation carried out in a manner similar to that described in example i , 5 . 5 kg of ( 2r - trans )-[ 2 -[( 2 - cyano -( 1 , 3 , 4 , 6 , 7 , 12b - hexahydro - 2h - benzothieno ( 2 , 3 - a ) quinolizine - 2 - yl )- amino ] ethyl ]- methanesulfonamide bis - hydrochloride is added to mixture of 7 . 5 kg of carbonyldiimidazole in 95 kg of tetrahydrofuran and 1 , 8 - diazabicyclo [ 5 . 4 . 0 ] undec - 7 - ene and the resulting mixture allowed to stand at ambient temperature to obtain compound d &# 34 ;. the reaction mixture is concentrated and then partitioned between ethyl acetate and water to recover compound d &# 34 ; in the organic layer . 4 . 5 kg of compound d &# 34 ; is added to a hydrogenation bomb containing 10 kg raney nickel catalyst and 190 kg methanol and hydrogenation carried out at 50 ° c . at 40 psig until the reaction is complete to obtain compound d &# 34 ;. compound d &# 34 ; is separated from the catalyst , the filtrate concentrated and 308 kg methylene chloride and 63 kg of saturated sodium bicarbonate added thereto and thoroughly mixed and they hydrogenation product recovered from methylene chloride solution and concentrated in the manner described in example i . the hydrogenation product is then added to the hcl generation mixture of acetyl chloride and methanol to obtain the desired compound i &# 34 ;. in a manner similar to that described in the preceding examples , the following compounds may be prepared : the starting material ( compound a ) may be prepared by the following sequence of reactions as described in the aforecited south african patent 87 / 6400 and also in u . s . pat . no . 4 , 710 , 504 , dec . 1 , 1987 , the teachings of which are incorporated by reference . ## str13 ## in carrying out the foregoing process , the aminomethyl compound ( a ) is heated with ethyl formate at about 60 ° c . for several hours , the reaction mixture then poured into dilute hydrochloric acid , the resulting mixture extracted with methylene chloride , the extract purified , dried , and the solvent evaporated to obtain the formamido compound ( b ). the latter is added to a strong acid or to a dehydrating agent such as polyphosphoric acid , phosphorus pentoxide , or methane sulfoncic acid at 100 ° c . and the mixture heated for 1 - 2 hours to obtain an ar - condensed dihydropyridine compound ( c ) which may be recovered by conventional procedures . compound ( c ) may than be converted to the quinolizin - 2 - one ( a ) by adding 2 - trimethylsilyloxy - 1 , 3 - butadiene , then zinc chloride , heating the mixture at 60 ° c . for 1 - 2 hours and thereafter recovering by conventional procedures . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 23aaf5c778a716f7cd3a37102cd2596a574c60c5601cc5a280d7a90a31b67d5b | 0.306641 | 0.055908 | 0.402344 | 0.090332 | 0.326172 | 0.101074 |
null | referring to fig1 a plurality of disks 10 are rotated by a spindle motor 34 . a plurality of heads 12 are respectively located on a plurality of disks and are installed on a plurality of support arms extended from a e - block assembly 14 assembled with a rotary voice coil actuator 30 to the disk . a pre - amplifier 16 supplies an analog read signal to a read / write channel circuit 18 by pre - amplifying a signal picked up by one of the heads 12 during reading , and lets a corresponding one of the heads 12 write on a disk by supplying coded write data output from the read / write channel circuit 18 . the read / write channel circuit 18 detects and decodes a data pulse from a read signal output by the pre - amplifier 16 and supplies it to a disk data controller ( hereinafter referred to as a ‘ ddc ’) 20 , and supplies write data from the ddc 20 to the pre - amplifier 16 by decoding . the ddc 20 writes data output from a host computer on a disk through the read / write channel circuit 18 and the pre - amplifier 16 , and transmits data to the host computer by reading it from a disk . the ddc 20 interfaces a communication between the host computer and a microcontroller 24 . a buffer ram 22 temporarily stores data transmitted between the host computer , the microcontroller 24 and the read / write channel circuit 18 . a microcontroller 24 controls a track detection and follow - up responding to an order of read or write received from the host computer . a rom 26 stores a performance program of the microcontroller 24 and all sorts of command values . servo driver 28 supplies a driving current to a voice coil of the actuator 30 . the actuator 30 moves the head 12 on the disk 10 according to the level and direction of the driving current . a spindle motor driver 32 rotates the disk 10 according to a control value generated by the microcontroller 24 . a disk signal controller 36 supplies a pes output from the read / write channel circuit 18 to the microcontroller 24 by converting it into a digital signal . referring to fig2 in two adjacent tracks , an n − 1 track ( odd number ) and an n track ( even number ), there exists an a burst , b burst , c burst and d burst for generating a pes . an a burst exists in the outside , being one half of each n − 1 track and n track . a b burst exists in the inside , being one half of each n − 1 track and n track . a c burst exists only in the n − 1 track , and a d burst exists only in the n track . according to the present invention , fig2 illustrates n and q defined as follows : fig2 illustrates each value of the n − 1 track and n track in each part of the n − 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n − 1 track and q equals d in a center line 40 of the n track . referring to fig1 and 3 a - 3 b , the microcontroller 24 checks to determine if there is a power on in step 100 and performs a track width measuring routine in step 102 . accordingly , the microcontroller 24 lets the head 12 seek a first track ‘ n ’ by servo - control in step 104 and thereafter confirms whether or not the seek has been completed by a servo signal read from the disk 10 in step 106 . if the seek has been completed , the microcontroller 24 waits for a fixed time for securing an accuracy of track width measuring and detection stabilization in step 108 . in step 110 , the microcontroller 24 sets a condition for measuring a track width and controls the head to move according to the condition ‘ n = q ’. referring to fig2 the head 12 remains near the center line 40 of the first track ‘ n ’ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a ‘ track - following line ’) when a track width measuring condition is set at n = q in step 110 . the track - following line 44 is positioned in a center between a center line 40 of track n and a line 48 adjacent to track n − 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the ‘ n ’ track along the track - following line when the head 12 is positioned at the track - following line 44 in step 110 and confirms the completion of track - following in step 113 . upon completion of track - following , it calculates the ‘ n ’ value and stores it in step 114 . when n is equal to a − b contours the track - following line 44 , a is not detected and only half of the b value is detected . accordingly , the n value is b / 2 . in step 116 , the microcontroller 24 lets the head 12 seek a second track by servo - control . the operations from steps 118 to 126 are similar to that from steps 106 to 114 . in steps 118 to 126 , the n value is calculated by following a track - following line 46 of an n − 1 track . when n is equal to a − b contours a track - following line 46 , b is not detected and only half of the a value is detected . accordingly , the n value is a / 2 . after performing steps 106 to 114 and 118 to 126 , the microcontroller 24 calculate a track width by adding the n value of track n to that of track n − 1 in step 130 . accordingly , the track width equals a + b / 2 . thereafter , the microcontroller 24 updates a percentage value of pes by measuring a track width in step 132 . accordingly the present invention measures a percentage value of pes by measuring a track width in measuring power - on operation , resulting in measuring a pes . it should be understood that the present invention is not limited to the particular embodiment disclosed herein as the best mode contemplated for carrying out the present invention , but rather that the present invention is not limited to the specific embodiments described in this specification except as defined in the appended claims . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.088867 | 0.003174 | 0.02124 | 0.000062 | 0.088867 | 0.002045 |
null | referring to fig1 a plurality of disks 10 are rotated by a spindle motor 34 . a plurality of heads 12 are respectively located on a plurality of disks and are installed on a plurality of support arms extended from a e - block assembly 14 assembled with a rotary voice coil actuator 30 to the disk . a pre - amplifier 16 supplies an analog read signal to a read / write channel circuit 18 by pre - amplifying a signal picked up by one of the heads 12 during reading , and lets a corresponding one of the heads 12 write on a disk by supplying coded write data output from the read / write channel circuit 18 . the read / write channel circuit 18 detects and decodes a data pulse from a read signal output by the pre - amplifier 16 and supplies it to a disk data controller ( hereinafter referred to as a ‘ ddc ’) 20 , and supplies write data from the ddc 20 to the pre - amplifier 16 by decoding . the ddc 20 writes data output from a host computer on a disk through the read / write channel circuit 18 and the pre - amplifier 16 , and transmits data to the host computer by reading it from a disk . the ddc 20 interfaces a communication between the host computer and a microcontroller 24 . a buffer ram 22 temporarily stores data transmitted between the host computer , the microcontroller 24 and the read / write channel circuit 18 . a microcontroller 24 controls a track detection and follow - up responding to an order of read or write received from the host computer . a rom 26 stores a performance program of the microcontroller 24 and all sorts of command values . servo driver 28 supplies a driving current to a voice coil of the actuator 30 . the actuator 30 moves the head 12 on the disk 10 according to the level and direction of the driving current . a spindle motor driver 32 rotates the disk 10 according to a control value generated by the microcontroller 24 . a disk signal controller 36 supplies a pes output from the read / write channel circuit 18 to the microcontroller 24 by converting it into a digital signal . referring to fig2 in two adjacent tracks , an n − 1 track ( odd number ) and an n track ( even number ), there exists an a burst , b burst , c burst and d burst for generating a pes . an a burst exists in the outside , being one half of each n − 1 track and n track . a b burst exists in the inside , being one half of each n − 1 track and n track . a c burst exists only in the n − 1 track , and a d burst exists only in the n track . according to the present invention , fig2 illustrates n and q defined as follows : fig2 illustrates each value of the n − 1 track and n track in each part of the n − 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n − 1 track and q equals d in a center line 40 of the n track . referring to fig1 and 3 a - 3 b , the microcontroller 24 checks to determine if there is a power on in step 100 and performs a track width measuring routine in step 102 . accordingly , the microcontroller 24 lets the head 12 seek a first track ‘ n ’ by servo - control in step 104 and thereafter confirms whether or not the seek has been completed by a servo signal read from the disk 10 in step 106 . if the seek has been completed , the microcontroller 24 waits for a fixed time for securing an accuracy of track width measuring and detection stabilization in step 108 . in step 110 , the microcontroller 24 sets a condition for measuring a track width and controls the head to move according to the condition ‘ n = q ’. referring to fig2 the head 12 remains near the center line 40 of the first track ‘ n ’ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a ‘ track - following line ’) when a track width measuring condition is set at n = q in step 110 . the track - following line 44 is positioned in a center between a center line 40 of track n and a line 48 adjacent to track n − 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the ‘ n ’ track along the track - following line when the head 12 is positioned at the track - following line 44 in step 110 and confirms the completion of track - following in step 113 . upon completion of track - following , it calculates the ‘ n ’ value and stores it in step 114 . when n is equal to a − b contours the track - following line 44 , a is not detected and only half of the b value is detected . accordingly , the n value is b / 2 . in step 116 , the microcontroller 24 lets the head 12 seek a second track by servo - control . the operations from steps 118 to 126 are similar to that from steps 106 to 114 . in steps 118 to 126 , the n value is calculated by following a track - following line 46 of an n − 1 track . when n is equal to a − b contours a track - following line 46 , b is not detected and only half of the a value is detected . accordingly , the n value is a / 2 . after performing steps 106 to 114 and 118 to 126 , the microcontroller 24 calculate a track width by adding the n value of track n to that of track n − 1 in step 130 . accordingly , the track width equals a + b / 2 . thereafter , the microcontroller 24 updates a percentage value of pes by measuring a track width in step 132 . accordingly the present invention measures a percentage value of pes by measuring a track width in measuring power - on operation , resulting in measuring a pes . it should be understood that the present invention is not limited to the particular embodiment disclosed herein as the best mode contemplated for carrying out the present invention , but rather that the present invention is not limited to the specific embodiments described in this specification except as defined in the appended claims . | Is this patent appropriately categorized as 'Physics'? | Is 'Performing Operations; Transporting' the correct technical category for the patent? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.341797 | 0.024414 | 0.523438 | 0.010986 | 0.211914 | 0.056641 |
null | referring to fig1 a plurality of disks 10 are rotated by a spindle motor 34 . a plurality of heads 12 are respectively located on a plurality of disks and are installed on a plurality of support arms extended from a e - block assembly 14 assembled with a rotary voice coil actuator 30 to the disk . a pre - amplifier 16 supplies an analog read signal to a read / write channel circuit 18 by pre - amplifying a signal picked up by one of the heads 12 during reading , and lets a corresponding one of the heads 12 write on a disk by supplying coded write data output from the read / write channel circuit 18 . the read / write channel circuit 18 detects and decodes a data pulse from a read signal output by the pre - amplifier 16 and supplies it to a disk data controller ( hereinafter referred to as a ‘ ddc ’) 20 , and supplies write data from the ddc 20 to the pre - amplifier 16 by decoding . the ddc 20 writes data output from a host computer on a disk through the read / write channel circuit 18 and the pre - amplifier 16 , and transmits data to the host computer by reading it from a disk . the ddc 20 interfaces a communication between the host computer and a microcontroller 24 . a buffer ram 22 temporarily stores data transmitted between the host computer , the microcontroller 24 and the read / write channel circuit 18 . a microcontroller 24 controls a track detection and follow - up responding to an order of read or write received from the host computer . a rom 26 stores a performance program of the microcontroller 24 and all sorts of command values . servo driver 28 supplies a driving current to a voice coil of the actuator 30 . the actuator 30 moves the head 12 on the disk 10 according to the level and direction of the driving current . a spindle motor driver 32 rotates the disk 10 according to a control value generated by the microcontroller 24 . a disk signal controller 36 supplies a pes output from the read / write channel circuit 18 to the microcontroller 24 by converting it into a digital signal . referring to fig2 in two adjacent tracks , an n − 1 track ( odd number ) and an n track ( even number ), there exists an a burst , b burst , c burst and d burst for generating a pes . an a burst exists in the outside , being one half of each n − 1 track and n track . a b burst exists in the inside , being one half of each n − 1 track and n track . a c burst exists only in the n − 1 track , and a d burst exists only in the n track . according to the present invention , fig2 illustrates n and q defined as follows : fig2 illustrates each value of the n − 1 track and n track in each part of the n − 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n − 1 track and q equals d in a center line 40 of the n track . referring to fig1 and 3 a - 3 b , the microcontroller 24 checks to determine if there is a power on in step 100 and performs a track width measuring routine in step 102 . accordingly , the microcontroller 24 lets the head 12 seek a first track ‘ n ’ by servo - control in step 104 and thereafter confirms whether or not the seek has been completed by a servo signal read from the disk 10 in step 106 . if the seek has been completed , the microcontroller 24 waits for a fixed time for securing an accuracy of track width measuring and detection stabilization in step 108 . in step 110 , the microcontroller 24 sets a condition for measuring a track width and controls the head to move according to the condition ‘ n = q ’. referring to fig2 the head 12 remains near the center line 40 of the first track ‘ n ’ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a ‘ track - following line ’) when a track width measuring condition is set at n = q in step 110 . the track - following line 44 is positioned in a center between a center line 40 of track n and a line 48 adjacent to track n − 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the ‘ n ’ track along the track - following line when the head 12 is positioned at the track - following line 44 in step 110 and confirms the completion of track - following in step 113 . upon completion of track - following , it calculates the ‘ n ’ value and stores it in step 114 . when n is equal to a − b contours the track - following line 44 , a is not detected and only half of the b value is detected . accordingly , the n value is b / 2 . in step 116 , the microcontroller 24 lets the head 12 seek a second track by servo - control . the operations from steps 118 to 126 are similar to that from steps 106 to 114 . in steps 118 to 126 , the n value is calculated by following a track - following line 46 of an n − 1 track . when n is equal to a − b contours a track - following line 46 , b is not detected and only half of the a value is detected . accordingly , the n value is a / 2 . after performing steps 106 to 114 and 118 to 126 , the microcontroller 24 calculate a track width by adding the n value of track n to that of track n − 1 in step 130 . accordingly , the track width equals a + b / 2 . thereafter , the microcontroller 24 updates a percentage value of pes by measuring a track width in step 132 . accordingly the present invention measures a percentage value of pes by measuring a track width in measuring power - on operation , resulting in measuring a pes . it should be understood that the present invention is not limited to the particular embodiment disclosed herein as the best mode contemplated for carrying out the present invention , but rather that the present invention is not limited to the specific embodiments described in this specification except as defined in the appended claims . | Is this patent appropriately categorized as 'Physics'? | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.341797 | 0.000048 | 0.523438 | 0.000033 | 0.211914 | 0.001137 |
null | referring to fig1 a plurality of disks 10 are rotated by a spindle motor 34 . a plurality of heads 12 are respectively located on a plurality of disks and are installed on a plurality of support arms extended from a e - block assembly 14 assembled with a rotary voice coil actuator 30 to the disk . a pre - amplifier 16 supplies an analog read signal to a read / write channel circuit 18 by pre - amplifying a signal picked up by one of the heads 12 during reading , and lets a corresponding one of the heads 12 write on a disk by supplying coded write data output from the read / write channel circuit 18 . the read / write channel circuit 18 detects and decodes a data pulse from a read signal output by the pre - amplifier 16 and supplies it to a disk data controller ( hereinafter referred to as a ‘ ddc ’) 20 , and supplies write data from the ddc 20 to the pre - amplifier 16 by decoding . the ddc 20 writes data output from a host computer on a disk through the read / write channel circuit 18 and the pre - amplifier 16 , and transmits data to the host computer by reading it from a disk . the ddc 20 interfaces a communication between the host computer and a microcontroller 24 . a buffer ram 22 temporarily stores data transmitted between the host computer , the microcontroller 24 and the read / write channel circuit 18 . a microcontroller 24 controls a track detection and follow - up responding to an order of read or write received from the host computer . a rom 26 stores a performance program of the microcontroller 24 and all sorts of command values . servo driver 28 supplies a driving current to a voice coil of the actuator 30 . the actuator 30 moves the head 12 on the disk 10 according to the level and direction of the driving current . a spindle motor driver 32 rotates the disk 10 according to a control value generated by the microcontroller 24 . a disk signal controller 36 supplies a pes output from the read / write channel circuit 18 to the microcontroller 24 by converting it into a digital signal . referring to fig2 in two adjacent tracks , an n − 1 track ( odd number ) and an n track ( even number ), there exists an a burst , b burst , c burst and d burst for generating a pes . an a burst exists in the outside , being one half of each n − 1 track and n track . a b burst exists in the inside , being one half of each n − 1 track and n track . a c burst exists only in the n − 1 track , and a d burst exists only in the n track . according to the present invention , fig2 illustrates n and q defined as follows : fig2 illustrates each value of the n − 1 track and n track in each part of the n − 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n − 1 track and q equals d in a center line 40 of the n track . referring to fig1 and 3 a - 3 b , the microcontroller 24 checks to determine if there is a power on in step 100 and performs a track width measuring routine in step 102 . accordingly , the microcontroller 24 lets the head 12 seek a first track ‘ n ’ by servo - control in step 104 and thereafter confirms whether or not the seek has been completed by a servo signal read from the disk 10 in step 106 . if the seek has been completed , the microcontroller 24 waits for a fixed time for securing an accuracy of track width measuring and detection stabilization in step 108 . in step 110 , the microcontroller 24 sets a condition for measuring a track width and controls the head to move according to the condition ‘ n = q ’. referring to fig2 the head 12 remains near the center line 40 of the first track ‘ n ’ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a ‘ track - following line ’) when a track width measuring condition is set at n = q in step 110 . the track - following line 44 is positioned in a center between a center line 40 of track n and a line 48 adjacent to track n − 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the ‘ n ’ track along the track - following line when the head 12 is positioned at the track - following line 44 in step 110 and confirms the completion of track - following in step 113 . upon completion of track - following , it calculates the ‘ n ’ value and stores it in step 114 . when n is equal to a − b contours the track - following line 44 , a is not detected and only half of the b value is detected . accordingly , the n value is b / 2 . in step 116 , the microcontroller 24 lets the head 12 seek a second track by servo - control . the operations from steps 118 to 126 are similar to that from steps 106 to 114 . in steps 118 to 126 , the n value is calculated by following a track - following line 46 of an n − 1 track . when n is equal to a − b contours a track - following line 46 , b is not detected and only half of the a value is detected . accordingly , the n value is a / 2 . after performing steps 106 to 114 and 118 to 126 , the microcontroller 24 calculate a track width by adding the n value of track n to that of track n − 1 in step 130 . accordingly , the track width equals a + b / 2 . thereafter , the microcontroller 24 updates a percentage value of pes by measuring a track width in step 132 . accordingly the present invention measures a percentage value of pes by measuring a track width in measuring power - on operation , resulting in measuring a pes . it should be understood that the present invention is not limited to the particular embodiment disclosed herein as the best mode contemplated for carrying out the present invention , but rather that the present invention is not limited to the specific embodiments described in this specification except as defined in the appended claims . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.088867 | 0.00007 | 0.02124 | 0.000003 | 0.088867 | 0.000881 |
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