input
null | response
stringlengths 1.55k
216k
| chosen_question
stringclasses 36
values | rejected_question
stringclasses 36
values | margin
float64 0.25
0.25
| pi_key
stringlengths 64
64
| pi_score_chosen
float64 0
0.97
| pi_score_rejected
float64 0
0.96
| pi_score_chosen_sfc_q_30750
float64 0
0.95
| pi_score_rejected_sfc_q_30750
float64 0
0.96
| pi_score_chosen_sfc_o_33000
float64 0
0.97
| pi_score_rejected_sfc_o_33000
float64 0
0.95
|
|---|---|---|---|---|---|---|---|---|---|---|---|
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 โ ddc โ) 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 โ 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 โ 1 track and n track . a b burst exists in the inside , being one half of each n โ 1 track and n track . a c burst exists only in the n โ 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 โ 1 track and n track in each part of the n โ 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n โ 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 โ n โ 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 โ n = q โ. referring to fig2 the head 12 remains near the center line 40 of the first track โ n โ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a โ track - following line โ) 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 โ 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the โ n โ 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 โ n โ value and stores it in step 114 . when n is equal to a โ 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 โ 1 track . when n is equal to a โ 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 โ 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 . | Does the content of this patent fall under the category of 'Physics'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.375 | 0.021606 | 0.269531 | 0.001167 | 0.255859 | 0.027588 |
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 โ ddc โ) 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 โ 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 โ 1 track and n track . a b burst exists in the inside , being one half of each n โ 1 track and n track . a c burst exists only in the n โ 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 โ 1 track and n track in each part of the n โ 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n โ 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 โ n โ 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 โ n = q โ. referring to fig2 the head 12 remains near the center line 40 of the first track โ n โ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a โ track - following line โ) 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 โ 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the โ n โ 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 โ n โ value and stores it in step 114 . when n is equal to a โ 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 โ 1 track . when n is equal to a โ 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 โ 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? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.088867 | 0.000315 | 0.02124 | 0.000261 | 0.088867 | 0.004059 |
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 โ ddc โ) 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 โ 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 โ 1 track and n track . a b burst exists in the inside , being one half of each n โ 1 track and n track . a c burst exists only in the n โ 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 โ 1 track and n track in each part of the n โ 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n โ 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 โ n โ 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 โ n = q โ. referring to fig2 the head 12 remains near the center line 40 of the first track โ n โ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a โ track - following line โ) 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 โ 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the โ n โ 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 โ n โ value and stores it in step 114 . when n is equal to a โ 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 โ 1 track . when n is equal to a โ 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 โ 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 'Electricity' the correct technical category for the patent? | 0.25 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.341797 | 0.01001 | 0.523438 | 0.002319 | 0.211914 | 0.001549 |
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 โ ddc โ) 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 โ 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 โ 1 track and n track . a b burst exists in the inside , being one half of each n โ 1 track and n track . a c burst exists only in the n โ 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 โ 1 track and n track in each part of the n โ 1 track and n btrack . n equals 0 ( zero ) in a center line 42 of the n โ 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 โ n โ 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 โ n = q โ. referring to fig2 the head 12 remains near the center line 40 of the first track โ n โ before step 110 . the head 12 moves to the line 44 for track - following ( hereinafter referred to as a โ track - following line โ) 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 โ 1 and parallel to each other . the track - following line 44 is positioned at the value of n = q . the microcontroller 24 follows the โ n โ 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 โ n โ value and stores it in step 114 . when n is equal to a โ 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 โ 1 track . when n is equal to a โ 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 โ 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 . | 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 | 6339dcc9f6bc7cac53ef6c171fcefb6ac6216d1c5a247b86a633d96225e07431 | 0.365234 | 0.044678 | 0.269531 | 0.004333 | 0.251953 | 0.048828 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Is this patent appropriately categorized as 'Electricity'? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.063477 | 0.047363 | 0.001648 | 0.001701 | 0.009155 | 0.043457 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Is 'Electricity' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.023315 | 0.009155 | 0.002472 | 0.004059 | 0.00592 | 0.018555 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Is 'Electricity' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.023315 | 0.000473 | 0.002472 | 0.000357 | 0.00592 | 0.00383 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Is this patent appropriately categorized as 'Electricity'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.063477 | 0.000109 | 0.001648 | 0.000004 | 0.009155 | 0.000458 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Should this patent be classified under 'Electricity'? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.070801 | 0.014954 | 0.002121 | 0.046143 | 0.007813 | 0.015442 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Should this patent be classified under 'Electricity'? | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.067383 | 0.00008 | 0.002121 | 0.000085 | 0.007813 | 0.000534 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Is 'Electricity' the correct technical category for the patent? | Is this patent appropriately categorized as 'Physics'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.023315 | 0.111328 | 0.002472 | 0.120117 | 0.00592 | 0.197266 |
null | the piezoelectric switch according to the present invention is designed to provide a simple , inexpensive switch which can be used in a wide number of applications . for example , individual switches , can be used to construct a computer keyboard , a telephone keypad , a cash register terminal , a control panel for machinery , elevator buttons , or any other device which requires a user to input information . piezoelectric switch 20 of the present invention is shown in an exploded view in fig2 . housing 22 forms a receptacle into which the remainder of the circuit elements are inserted . housing 22 is formed of a material which is rigid but somewhat flexible , for example , plastic or stainless steel . one example of such a plastic material is the product sold under the trademark lexan ยฎ manufactured by general electric company . the material must be sufficiently flexible so that it is deformable in response to external pressure which is applied to activate the switch . for example , if the switch is to be used as a telephone keypad , the person would press the indicia for the number he is entering . the pressure caused thereby would deform the housing , which transformation in turn would be transmitted to the piezoelectric ceramic 24 . it also must be sufficiently flexible to allow such fitting of the various switch elements within the housing and to allow such fitting of the housing in the device in which it is to be used . the material must also be sufficiently rigid so as to protect the piezoelectric ceramic from damage . housing 22 includes a ring shaped support 210 on which all other portions of the housing are attached . support 210 has a substantially circular shape , however , two portions form flattened portions 214 . descending from one surface of support 210 , at portions 214 , are two clips 216 which can be used to removably secure the switch to the device in which it is being used . these clips 216 are squeezed toward one another during insertion and , when in place , flange 218 acts to secure the switch to the device ( not shown ). also descending from support 210 at approximately the position of the flattened portions 214 are supports 220 which form supports for bridge 202 . four posts 204 are attached to bridge 202 on the inside of support 210 . two of the posts 204 are positioned adjacent to each flattened portion 214 and are spaced from one another along the respective flattened portion . the amount of spacing is sufficient to allow an anisotropic conductive rubber element 26 ( described below ) to be inserted therebetween . groove 212 is formed in the inside surface of bridge 202 . posts 206 extend from the opposite surface of support 210 at positions 90 ยฐ from flattened portions 214 . posts 206 include inwardly facing flanges 208 which act to keep printed circuit board 28 in place when the switch is assembled . the printed circuit board 28 snaps into place within the housing 22 . cutouts 280 on printed circuit board 28 engage portions 222 of posts 206 when the switch is assembled to assure correct positioning of the switch elements within housing 22 . piezoelectric ceramic element 24 is fixed to the undersurface of bridge 202 by an insulating adhesive 244 ( fig3 ). both the positive and the negative contacts , 240 and 242 , respectively , are located on the side of the ceramic which is not fixed to bridge 202 . a gap 243 is formed between poles 240 and 242 . in this way , by providing both contacts on one side , the ceramic is easily electrically connected to the remainder of the circuit elements . the polarity of the poles is interchangeable . the ceramic element 24 can be made from a standard ceramic material . in the preferred embodiment , ppk21 is used , manufactured by stettner & amp ; co . of lauf , federal republic of germany . the piezoelectric ceramic exhibits a high coupling factor , high permittivity , high piezoelectric strain constant and broadband behavior through low mechanical q - factor . the anisotropic conductive elastomeric connector 26 is disposed so as to have one longitudinal edge extend across the longitudinal exposed face of the piezoelectric element 24 . the connector 26 is inserted into the housing 22 in the space formed by posts 204 . the connector is held within the housing by the printed circuit 28 when the board is snapped into place . connector 26 may be any anisotropic conductive elastomeric material but is preferably a series 1000 / 2000 zebra ยฎ connector manufactured by tecknit co ., of cranford , n . j . such a connector is formed as a sandwich , in which a conductive portion 264 is layered between two insulating layers 262 . conductive portion 264 is constructed of strips of insulating material 266 alternating with strips of conductive material 268 , shown in fig3 . in this particular case the positive pole 240 of the piezoelectric ceramic is linked electrically through the conductive portions 268 of connector 26 to contact 284 of printed circuit board 28 . negative pole 242 is linked electrically to contact 282 . the anisotropicity caused by the alternating conductive and insulating strips 268 , 266 permits electrical connection of the respective contacts without permitting short - circuiting of contacts of opposite polarity . the use of such an elastomeric connector facilitates the snap fitting of the component into the housing 22 and protects the piezoelectrc ceramic 24 from physical shock which may come from the direction of the open side of the housing 22 . furthermore , the combination of the elastomeric connector with the piezoelectric ceramic having both poles on one side allows all electrical connections between the ceramic and the printed circuit board to be solder - free . fig4 is a schematic of the circuit of printed circuit board 28 . the circuit 1 forming the piezoelectric switch according to the present invention is shown outlined in broken lines . the circuit prevents any electrical signal from passing from the printed circuit board through anisotropic conductive elastomeric connector to the piezoelectric ceramic 24 and also transmits any electrical signal received from the ceramic 24 to the outside world . in particular , the circuit includes two resistors 290 and 292 , two transistors 286 and 288 and a diode 294 . when an electrical signal develops within the piezoelectric ceramic , from a mechanical force exerted on the switch , the gates of the transistors 286 and 288 are polarized positively . the impedance between the source and the drain of transistors 286 and 288 falls from 5 mฯ ( typ ) to approximately 0ฯ . this will enable any external circuit which includes a source ( battery 296 ) and a load 298 to be switched on . the signal from the piezoelectric crystal 24 is sufficiently high to open the gates of the transistors 286 and 288 . however , sometimes this signal is too high , which will overload the two transistors . diode 294 is included to maintain the signal at a safe level . contacts 30 are provided on the outside surface of printed circuit baord 28 to provide contact with the external device . the contacts may be plug terminals as shown in fig2 or they may be formed as straight pin contacts . one embodiment of the switch is shown and described herein . a number of switches could be connected together to form a keyboard or other similar device , for example in the keyboard shown in fig5 . the individual switches would be connected together to form a keyboard according to known principles of keyboard construction . it is understood that it would be possible to construct other embodiments of the switch which are designed to implement a particular application . for example , it would be possible to provide a single housing which would form the entire keyboard , with indicia for the keyboard characters on one side of the housing , and , for each area having an indicia , an individual piezoelectric element , elastomeric conductor and printed circuit board could be fixed thereto . it is understood that the shape of the housing 22 may be adapted to the particular needs of the application . for example , it may be square , rectangular or oval . the construction of the switch , and the ease with which the parts of the switch are assembled in the housing , yields a switch which is fully modular . it is a self - contained element which has no moving parts , is easy to assemble and easily snaps into place in the system in which it is to be used . the foregoing description of the specific embodiments will so fully reveal the general nature of the invention that others can , by applying current knowledge , readily modify and / or adapt for various applications such specific embodiments without departing from the generic concept , and , therefore , such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments . it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation . | Does the content of this patent fall under the category of 'Electricity'? | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | 0.25 | a796eaeac69c96d591ed2019f432b6e3dc9d93645d512d455e118d553e536e75 | 0.172852 | 0.108398 | 0.003372 | 0.589844 | 0.024048 | 0.185547 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.129883 | 0.015869 | 0.484375 | 0.001457 | 0.162109 | 0.008301 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.235352 | 0.010681 | 0.730469 | 0.002258 | 0.28125 | 0.025513 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.137695 | 0.275391 | 0.447266 | 0.396484 | 0.211914 | 0.241211 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Should this patent be classified under 'Textiles; Paper'? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.168945 | 0.01001 | 0.683594 | 0.001244 | 0.199219 | 0.022583 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.235352 | 0.012024 | 0.730469 | 0.022583 | 0.28125 | 0.016968 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.137695 | 0.000999 | 0.447266 | 0.000103 | 0.211914 | 0.002045 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Does the content of this patent fall under the category of 'General tagging of new or cross-sectional technology'? | Is this patent appropriately categorized as 'Physics'? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.140625 | 0.119141 | 0.447266 | 0.069336 | 0.211914 | 0.102539 |
null | the present invention provides a novel catalyst for the water - gas shift reaction , a method for preparing this catalyst and a method for conducting the water - gas shift reaction in the presence of this catalyst . the catalyst of this invention shows substantially higher activity and stability when compared to other catalysts . the catalyst of the present invention comprises highly dispersed group 1b metal on a crystalline sulfated zirconia support optionally in association with modifiers and additives such as , for example group i , group ii and rare earth oxides . surprisingly we have discovered that unusually active and stable wgs catalysts can be prepared when sulfated zirconia is used for the catalyst preparation . the presence of sulfate is critical for making the catalyst of the present invention with its outstanding performance . in a preferred embodiment of the catalyst of the present invention it has been found that the sulfur level should be at least 0 . 02 wt % based on the weight of zirconia ( also referred to as zirconium oxide or zro 2 ). preferably the sulfur level of the catalyst should be between 0 . 02 and 4 . 0 wt % based on the weight of zirconium oxide more preferably between 0 . 02 and 3 . 5 wt %, still more preferably between 0 . 02 and 2 . 5 wt % and most preferably between 0 . 02 and 1 wt % based on the wt of the zirconium oxide . we have further discovered that the catalyst of the present invention can operate in what is considered to be high temperature shift range down into the low and even ultra low temperature range . thus the process of the present invention when using the novel catalyst of the invention is able to operate over a temperature range from about 100 degrees c . to about 500 degrees c . in a typical preparation , the catalysts of this invention are prepared by an aqueous gold deposition onto a calcined sulfated zirconia support . this is usually followed by drying in air at around ambient temperature or slightly higher , e . g ., about 35 ยฐ c . prior to use the catalyst is generally activated in the reactor under nitrogen at 250 ยฐ c . for about 2 hours . not wishing to be bound by any particular theory we believe that it is extremely important to keep group 1b metal from reducing to a zero valence metal state during the group 1b metal deposition process . also it is believed that the sulfated zirconia support plays a critical role in keeping gold well dispersed . additionally it is believed that it is advantageous for at least some of the zirconia to be in the tetragonal phase . as discussed above a highly dispersed group 1b metal is an essential feature of the catalyst used in the present invention . the group 1b metals are gold , silver and copper . in a preferred embodiment of the present invention the highly dispersed group 1b metal should be gold . in another embodiment of the present invention a mixture of group 1b metals can be used . preferably the mixture of group 1b metals includes at least some gold . in a preferred embodiment of the present invention a majority of the zirconia in the catalyst should be in the tetragonal phase , more preferably the zirconia should be predominately in the tetragonal phase . the phase of the zirconia can be determined by the pxrd ( powder x - ray diffraction ) pattern of the catalyst sample . the x - ray diffraction pattern can be used to determine the phase of the zirconia due to the different phases exhibit characteristic lines in the pattern . it was demonstrated by scanning electron microscopy ( sem ) and transmission electron microscopy ( tem ) that the catalysts of this invention most preferably have no detectable gold particles after gold deposition and drying steps . in the catalyst and method of the present invention the gold loading of the catalyst should be at least 0 . 001 wt % based on the weight of zirconium oxide in the catalyst . preferably the gold loading of the catalyst should be between 0 . 001 and 5 . 0 wt %, more preferably between 0 . 001 and 4 . 0 wt %, still more preferably between 0 . 01 and 3 . 0 wt %, even more preferably between 0 . 1 and 3 . 0 wt %, and most preferably between 0 . 1 and 2 . 0 wt % based on the weight of zirconium oxide in the catalyst . when silver or copper are used in the catalyst either alone or in combination with gold higher levels may be required than gold alone to achieve the same level of catalytic activity . another important feature of the catalyst of the present invention is that the gold be very highly dispersed on the catalyst . the methods for gold loading described in the detailed description of the present invention and in the examples can lead to a very highly dispersed catalyst . activation conditions must also be carefully selected to avoid agglomeration of the gold ( or other group 1b metal ) and loss of the very high dispersion . it is preferred that at least 80 wt % of the gold be dispersed in particles of less than 10 angstroms when measured by tem . more preferably at least 90 wt % of the gold should be dispersed in particles of less than 10 angstroms when measured by tem . most preferably there should be no detectable gold particles on the catalyst after gold deposition and drying steps when examined by tem and sem . in the present application the phrase no detectable gold particles means essentially no particles having an approximate diameter above about 7 to 9 angstroms . there is a trade off between the amount of surface area and stabiliy of the sulfated zirconia support . so it is important that the zirconia surface area of the sulfated zirconia support be carefully controlled . the bet ( brunauer , emmett , teller ) surface area of the sulfated zirconia support should be at least 5 m 2 / g , preferably at least 10 m 2 / g , more preferably between 10 and 500 m 2 / g , still more preferably between 30 and 250 m 2 / g and most preferably between 50 and 100 m 2 / g . the bet surface area can be determined using astm d 4567 ( volume 5 . 03 ) or astm d 3663 which are incorporated herein by reference . as mentioned above it is also critical to the present invention that the catalyst comprise sulfated zirconia . it has been found that by employing the sulfated catalyst described above that the method of the present invention displayed surprisingly low deactivation rates . methods for making a sulfated zirconia material suitable for use as a starting material in the preparation of the catalyst of the present invention can be found in u . s . pat . nos . 6 , 448 , 198 and 6 , 180 , 555 which are incorporated herein in their entirety . in addition to the sulfated zirconia , the catalyst of the present invention optionally can include an additional structural support material such as a refractory metal oxide material such as for example silica , alumina , magnesia , titania , etc . and mixtures thereof . the structural support can be in any form including for example monolith , spheres , or hollow cylinders . more specifically the structural support material can additionally include โ supports โ such as alumina , silica , silica - alumina , silicate , alumino - silicate , magnesia , zeolite , active carbon , titanium oxide , thorium oxide , clay and any combination of these supports . in one embodiment of the present invention preferably , the invention &# 39 ; s catalyst can contain between 50 % and 95 % by weight of structural support , on which 5 % to 50 % of sulfated zirconia by weight is deposited . in the method of the present invention the catalyst has been found to be effective at a surprisingly broad range of temperatures . in the method of the present invention the water - gas shift reaction can be carried out between 100 and 500 ยฐ c . preferably between 135 and 420 ยฐ c . it is understood by one of skill in the art that as catalysts become less active the reaction temperature may be increased to achieve a target conversion . however , increasing temperatures leads to an increased concentration of co due to a shift in equilibrium . space velocities useable in the method of the present invention as measured by gas hourly space velocity ( ghsv ) are between 1000 h โ 1 to 200 , 000 h โ 1 , preferably between 10 , 000 h โ 1 to 100 , 000 h โ 1 , more preferably between 25 , 000 h โ 1 to 100 , 000 h โ 1 . it is understood by one of skill that the space velocity can be decreased to compensate for lower activity . as mentioned above in one embodiment of the present invention the method can optionally include a co oxidation zone in order to reduce the level of co in the h 2 such that it is suitable for use in a fuel cell such as a pem fuel cell . a potential advantage of the present invention is that the wgs method of the present invention can be used to convert most of the co while also making hydrogen and leaving only a small amount or trace amount of co to be oxidized in the co oxidation zone . this means that the co oxidation zone can be smaller in size and can further reduce the size and complexity of a fuel processor system . under some circumstances the co oxidation zone may be eliminated entirely . an example of a fuel processor that includes a combination partial oxidation / steam reforming zone , wgs zone , and co oxidation zone is shown in u . s . pat . no . 6 , 521 , 204 which is incorporated herein in its entirety . alternatively the present invention provides a catalyst and method for co oxidation . as discussed above co oxidation can be used to remove the last traces of co to achieve a h 2 stream containing very low levels of co . the co oxidation method and catalyst of the present can be used in conjunction with the wgs method and catalyst or can be used independently . this example shows the preparation of a mass sulfated zirconia material that can be used as a base for the catalyst of the present invention . 35 g of zro ( no 3 ) 2 , 6h 2 o is dissolved in 350 ml of distilled water with agitation . zirconium hydroxide gel is precipitated by adding 17 ml of a 28 % ammonia solution while agitating . the final ph is about 8 . 5 . after filtering and washing until a ph 7 ( redispersal in 350 ml of water ), the gel is dried overnight at 120 degrees c . the result is about 13 . 8 g of a solid . the sulfation is done by adding 85 ml of sulfuric acid ( 1 n ), by static contact for 15 minutes . the sulfated zirconia is then spun dry . then the material is dried overnight at 120 degrees c . this example shows the preparation of a structurally supported sulfated zirconia base that can be used in the catalyst of the present invention . the catalyst sample is prepared starting from 25 g of an alumina support , marketed by akzo under the name ck 300 , previously calcined at 600 degrees c . the zirconium deposition is done in a ball by impregnating the support with a solution formed by the dissolution of 3 . 48 g of zirconyl chloride ( zrocl 2 , 8h 2 o , marketed by prolabo also available from aldrich ) and 0 . 46 g of nh 4 cl in 11 cm 3 of distilled water , with a volume corresponding to the porous volume of the support . the solid obtained is first dried overnight at 120 degrees c . then calcined for 2 hours at 650 degrees c . this operation is repeated twice ( deposit of zirconium three times ), then the solid obtained is calcined for 4 hours at 750 degrees c . thereafter , the sulfation of the zirconium deposited on the surface of the alumina support takes place by circulating 162 cm 3 of a sulfuric acid solution ( 5 n ) at room temperature for 1 hour . then the solid is spun - dry then allowed to dry overnight at 120 degrees c . next it is calcined for 2 hours at 500 degrees c . in a flow of dry air at 60 liters per hour . a sample of sulfated zirconium hydroxide powder containing about 2 % wt of sulfate was calcined in air at 660 ยฐ c . according to the following procedure . sulfated zirconium hydroxide can be obtained from commercial sources such as aldrich . the sample was heated up to 660 ยฐ c . slowly over 10 hours and kept at this temperature for 6 hrs , followed by slow cooling to ambient temperature . the nitrogen bet ( brunauer , emmett , teller ) surface area of the powder before the calcinations was found to be 284 m 2 / g and after the calcinations it was 75 m 2 / g . the starting powder was amorphous by powder x - ray diffraction ( pxrd ). the pxrd pattern of the calcined material was that of the tetragonal phase of zirconia containing a small amount of the monoclinic phase . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 34 g of haucl 4 ร 3h 2 o in 600 ml of distilled water and then heating the solution to about 60 ยฐ c . the acidity of the solution was adjusted to ph 8 . 6 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was removed by filtration and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the resulting catalyst had a nitrogen bet surface area unchanged of about 75 m 2 / g . the pxrd pattern of the gold deposited sample showed both tetragonal and monoclinic phases of zirconia present in almost equal amounts . elemental analysis results for various samples prepared by the above procedure showed that the amount of sulfate decreased to about 0 . 26 % wt . and the gold loading were in the range of 1 % wt . to 2 % wt . the gold was deposited on the calcined sample from example 3 by first preparing a solution of 0 . 20 g of haucl 4 ร 3h 2 o in 60 ml of distilled water and then heating the solution to about 60 ยฐ c . the ph of the solution was adjusted to values between 9 and 10 by the addition of a 1 . 0 m sodium carbonate solution . 6 g of the calcined sulfated zirconia sample was added to the solution and stirred for 2 to 3 hrs by slow rotation in a rotary evaporator . the resulting solid was separated by filtration , rinsed with 100 ml of distilled water and dried in an air convection oven at 35 ยฐ c . overnight . finally the dry powdered sample was pressed and sized to โ 18 /+ 40 ( us ) mesh for the reactor testing . the catalyst of this invention can also be prepared by near incipient wetness impregnation procedures of a gold compound on the sulfated zirconia support . methods of near incipient wetness impregnation are taught in the art . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalysts were tested in the temperature range of 135 ยฐ c . to 420 ยฐ c . at space velocities of 2000 h โ 1 to 50000 h โ 1 based upon the volume of catalyst . two different gas mixtures were used in the testing . the gas mixtures were produced either by blending four syngas components โ co , h 2 , n 2 and co 2 in a manifold or by using a mixture of a pre - defined composition . water was introduced to the gas stream as vapor produced by heating the stream of liquid water in a small flash vessel just below the boiling point of water at the reactor pressure . for example , for the reaction mixture of the following composition โ 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 20 , 000 ghsv , 200 ยฐ c . and 30 psig the catalyst had constant activity at equilibrium co conversion of about 98 . 2 % for the time it had been tested of about 350 hours . at the same conditions but at a temperature of 350 ยฐ c . the catalyst operated at constant activity and equilibrium conversion of about 86 . 1 %. the results of catalyst performance at 240 ยฐ c . over a range of space velocities for the reaction mixture composition of 4 . 65 % vol . co , 34 . 31 % vol . h 2 , 7 . 43 % vol . co 2 , 13 . 73 % vol . n 2 , 36 % vol . h 2 o are shown in fig1 . the changes of the catalyst activity with temperature at 20 , 000 ghsv are shown in fig2 and over a range of space velocities at different temperatures in fig3 for this same gas mixture . finally , for both reaction mixtures it was demonstrated that the catalyst could be cooled down to an ambient temperature in air , then heated back to a reaction temperature and restarted without loss of activity repeatedly . the catalyst from example 2 was tested for effects of the feed mixture , in particular water , during temperature shutdown on catalyst performance . initially , the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 31 . 1 % vol . n 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . after the stable co conversion was attained the heat to the reactor was turned off and the reactor was allowed to cool under the feed to ambient temperature . it was kept at these conditions for 1 hr followed by reheating of the reactor to 200 ยฐ c . under 200 sccm of nitrogen and re - introduction of the feed mixture . after the stable co conversion was attained the procedure was repeated . for this particular experiment after ten cycles the co conversion remained unchanged at about 73 % at 10 , 000 ghsv . this example demonstrates that the exposure of the catalyst to condensed water vapor does not affect significantly it &# 39 ; s reactor performance . the catalyst of example 2 was tested for effects of oxygen in the feed mixture . the reactor run was started according to the procedure in the previous example using the feed mixture containing 11 % vol . co , 25 . 6 % vol . h 2 , 6 . 8 % vol . co 2 , 26 . 1 % vol . n 2 , 5 . 0 % vol . o 2 , 25 . 4 % vol . h 2 o , at 200 ยฐ c . and 30 psig . the catalyst was run at these conditions for about 40 hours at average co conversion of 98 %. no significant loss of hydrogen was observed . 2 cc of the catalyst from example 2 was diluted with 6 cc of acid - washed alundum of the same size and loaded into a ยฝ โณ o . d . stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the catalyst was heated to up 250 ยฐ c . at a rate of 50 ยฐ c ./ h in a 200 sccm flow of nitrogen overnight and then cooled to a test temperature . the catalyst was tested for co oxidation activity by introducing to the reactor a co / air feed at the ratio of 2 to 3 at 6000 h โ 1 ghsv at room temperature . the temperature in the reactor increased to about 150 ยฐ c . when oxygen conversion approached 100 % and stabilized . no decline in co conversion was observed over 120 hrs operation . in the same experiment the feed to the reactor was switched back and forth between the co / air mixture and the typical wgs feed as in example 8 . at 20000 h โ 1 ghsv , 200 ยฐ c . and 30 psi the co conversion remained on average at about 98 %. this example clearly demonstrates that the same catalyst is very active catalyst for both wgs and co oxidation reactions . a sample of gold on zirconia was prepared as follows . 0 . 33 g of haucl 4 ร 3h 2 o was added to 600 ml of deionized water then heated to 60 degrees c . the ph was adjusted by dropwise addition of 1n na 2 co 3 until the solution cleared . the final ph was 8 . 55 . 3 . 09 g of zirconium iv oxide extrudate was placed in a round bottom flask along with the gold containing solution . the flask was placed on a rotory evaporator and immersed in a bath that was maintained at 60 degrees c . the flask was allowed to rotate for 2 hours 10 minutes . the extrudate was then filtered from the solution . the extrudate had maintained their shape and rigidity after filtering . the extrudate was dried . 1 . 5 cc ( 1 . 7 g ) of the au on zirconia catalyst formed in comparative example 7 was loaded into a wgs tube reactor . the sample was first diluted with 6 . 5 cc of acid - washed 24 / 48 alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 85 %. however at constant temperature ( 200 degrees c .) after 10 hours the conversion declined to about 72 % and after 20 hours to about 64 %. 2 . 0 cc ( 2 . 45 g ) of au on sulfated zirconia catalyst was loaded into a wgs tube reactor . the sample was first diluted with 6 . 0 cc of acid - washed 24 mesh alundum and loaded into the ยฝ โณ od stainless steel tube reactor . the catalyst bed was held in place with alundum and glass wool plugs on both ends . the reactor was heated to 200 degrees c . with a n 2 flow rate of 200 cc / min . the temperature was held at 200 degrees c . for 1 hour then the syngas mixture was introduced as the feed . the pressure was raised to 30 psig and the syngas flow rate was set at 80 . 0 cc / min . h 2 o was injected at a flow rate of 0 . 0165 ml / hr to achieve a space velocity of 4000 hr โ 1 . the process achieved a co conversion initially of as much as 96 %. after 20 hours of operation the conversion was at about 95 %. this example shows that the au on sulfated zirconia achieves better conversion and better stability than unsulfated au on zirconia catalyst ( see comparative example 12 ) at the same process conditions . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Is 'Electricity' the correct technical category for the patent? | 0.25 | dcb93ca0f5dd7579ee5e1587270ff80fd07be13a0a865fabbd897f9e752d2994 | 0.168945 | 0.000969 | 0.683594 | 0.000345 | 0.199219 | 0.000607 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Is 'Electricity' the correct technical category for the patent? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.072754 | 0.004761 | 0.003174 | 0.000191 | 0.056641 | 0.005066 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Does the content of this patent fall under the category of 'Electricity'? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.138672 | 0.007568 | 0.001755 | 0.000504 | 0.158203 | 0.011353 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Should this patent be classified under 'Electricity'? | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.103516 | 0.000444 | 0.003082 | 0.000132 | 0.07373 | 0.000854 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Is 'Electricity' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.072754 | 0.001595 | 0.003174 | 0.000296 | 0.056641 | 0.013245 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Should this patent be classified under 'Electricity'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.103516 | 0.015869 | 0.002975 | 0.00193 | 0.07373 | 0.032471 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Is this patent appropriately categorized as 'Electricity'? | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.126953 | 0.000969 | 0.011353 | 0.00014 | 0.149414 | 0.005737 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Does the content of this patent fall under the category of 'Electricity'? | Is 'Physics' the correct technical category for the patent? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.138672 | 0.157227 | 0.00193 | 0.054199 | 0.164063 | 0.267578 |
null | referring to fig1 a schematic diagram of a phase lock loop utilizing the preferred phase detector is shown . the phase lock loop functions to maintain the frequency of a voltage control oscillator ( vco ) 40 output frequency at a desired point . the vco 40 is controlled by a current source in a phase detector 20 which has its outputs connected to the input of the adaptive loop filter 30 . adaptive loop filter 30 is a transimpedance type , in which current is received at the input port and voltage is provided at the output port . the current sources of the phase detector vary the voltage in the adaptive loop filter 30 by sourcing or sinking current . the output voltage of the adaptive loop filter 30 is connected to the input of the vco 40 . the vco 40 is an oscillator whose output frequency is responsive to the input voltage from the adaptive loop filter 30 . the output of the vco 40 is applied to a loop divider 50 . the divided output of the loop divider 50 , f v , is applied to the phase detector 20 . the output signal of a reference oscillator 10 , f r is also applied to the phase detector . the phase lock loop maintains f v in phase with f r by producing a signal at the phase detector output which manipulates the vco 40 to correct for differences between f v and f r . referring to fig2 a preferred phase detector 20 is shown . during the normal mode of operation for the phase lock loop , shown in fig1 a dual state phase detector 28 is used to compare the difference between the vco frequency and the reference frequency and provide a corresponding output 38 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . patent application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . however , when a need arises for the fast change of the characteristics of the phase lock loop , a conventional tri - state phase detector cell 32 , with an inverter 34 connected to its reference input port , is used to compare the difference between the vco frequency and reference frequency and provide the corresponding output 42 . the tri - state phase detector cell 32 is designed to provide a higher output current than the dual state phase detector 28 . this allows the phase detector 20 , when necessary , to steer more rapidly . rapid steering is achieved , by increasing the current provided to or from the phase detector 20 to the adaptive loop filter 30 , resulting in the filter charging or discharging voltage at a more rapid rate . a tri - state phase detector cell is disclosed in u . s . pat . no . 4 , 764 , 737 , issue aug . 16 , 1988 , that provides rapid steering , the patent is hereby incorporated by reference . a control means selects the output of either the dual state phase detector cell 28 or the output of the tri - state phase detector cell 32 , depending on the needs of the phase lock loop . an external source , usually a microprocessor , provides an input signal to the control input 2 that activates the control means . the control means includes : a control input 2 , an inverter 8 , and and gates 12 , 14 , and 16 . the control means acts to disable one of the phase detectors 28 or 32 which is not in use during a particular mode of operation . the output includes : a current source 18 , a current sink 22 , a current source 24 , and a current sink 26 . the output current sources of the dual state phase detector are 18 and 22 . one of dual state phase detector output current sources has a fixed current of value i / 2 and the other current source has a switched current of value i . the two current sources are arranged in a pair in which one is a source and the other is a sink . when the dual state phase detector cell is at steady state , the inputs 4 and 6 are of equal frequency and 180 ยฐ phase offset . current source 18 is on 50 % of the time and the net charge transfer at output 38 is zero over one cycle . the output 42 of the tri - state detector cells is provided by current sources 24 and 26 . when on , the output 42 of current sources 24 and 26 is higher than the output 38 of the dual state phase detector 28 , provided by current sources 18 and 22 . this allows the tri - state phase detector to provide rapid steering in the pll . assuming the inverter 8 receives a high logic signal from the control input 2 , a logic low signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 does not provide a logic high signal to activate the active high current source 18 . current source 18 is unable to provide current to output 38 . in addition , the logic low signal provided by the inverter 8 not does activate the current sink 22 , therefor , the output of the dual state phase detector cell 28 is disabled . conversely , assuming the inverter 8 receives a low logic signal from the control input 2 , a logic high signal is provided from the inverter 8 and received by one of the input ports of the and gate 12 . if the &# 34 ; up &# 34 ; port of the dual state phase detector cell 28 provides a logic high signal that is received by the other input port of the and gate 12 , then the and gate 12 provides a logic signal to activate the current source 18 . current source 18 provides a current to output 38 . current source 22 is enabled . assuming control input 2 receives a logic high signal , a l logic high signal is provided to one of the input ports of the and gate 14 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 provides a logic low signal that is received by the other input port of the and gate 14 , then the and gate 14 does not provide a logic signal to activate the current sink 26 . if the &# 34 ; down &# 34 ; port of the tri - state phase detector cell 32 is high , current sink 26 is enabled . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 14 . if the control input 2 receives a logic low signal , current sink 26 is off whether the &# 34 ; down &# 34 ; port of the tri - state phase detector is high or low . assuming control input 2 receives a logic high signal , a logic high signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 provides a logic high signal to activate the active high current source 24 . the current source 24 provide current to the output 42 . conversely , assuming control input 2 receives a logic low signal , a logic low signal is received by one of the input ports of the and gate 16 . if the &# 34 ; up &# 34 ; port of the tri - state phase detector cell 32 provides a logic high signal that is received by the other input port of the and gate 16 , then the and gate 16 does not provide the logic signal to activated the current source 24 . the current source 24 does not provide a current to output 42 . therefor , when the control input 2 receives a low signal , the tri - state output current sources are disabled . referring to fig3 a schematic diagram of the adaptive loop filter 30 is shown . an input 44 is connected to the output 38 of the phase detector while input 46 is connected to the output 42 . a gate 64 , controlled by the adapt signal of input 2 , is used to switch the input 46 directly to the output of the loop filter and thereby directly charge output capacitor 62 . a resistor 48 couples input 46 to a capacitor 56 . input 44 is coupled in a conventional manner by parallel connected resistor 52 and capacitor 54 to capacitor 56 , and by resistor 58 to the filter output . in normal practice , capacitor 62 is much smaller in size than capacitor 56 . therefore , capacitor 56 is the primary storage element in the adaptive loop filter 30 . the charged stored across capacitor 56 is the steady state voltage used to set the vco frequency . referring to fig4 a preferred dual state phase detector cell 28 is shown . the dual state phase detector cell 28 comprises d flip - flops 70 and 80 . in the preferred embodiment of the invention , the flip - flops 70 and 80 are edge triggered flip - flops , and respond to a leading edge transition at their clock ( clk ) input . a logic high or a logic low in the preferred embodiment may be any suitable voltage potential , such as + 5 v for a logic high and 0 v for a logic low . a logic high at the reset ( r ) input will provide a logic low at the q output and a logic high at the q bar output of the flip - flops . a first digital signal 6 , which may be a reference frequency signal for a pll circuit is received at f r , and is applied to the clock inputs of the flip - flop 70 . a second digital signal 4 , which may be a divided down vco signal , is received at f v , and is applied to the clock inputs of the flip - flop 80 . the d inputs of the flip - flop 70 and 80 coupled to a logic high . operation of of the dual state phase detector cell 28 may be best understood by assuming that the phase difference between the leading edge of the first input signal 6 and the second input signal 4 is less than 360 degrees , and that the leading edge of the first signal 6 occurs before the leading edge of the second signal 4 . under this condition , the second signal 4 has only one leading edge occurring within one cycle of the first signal 6 . in this case , the leading edge of the first signal 6 forces the q output 74 of the flip - flop 70 to a logic high . the q bar output of flip - flop 70 presents a logic low to the reset input of flip - flop 80 . upon the occurrence of the leading edge of the second signal 4 , a logic high on the q output of the flip - flop 80 resets the flip - flop 70 and forces the output 74 to a logic low . accordingly , the duty cycle of the output 74 which is the &# 34 ; up &# 34 ; signal to and gate 12 , is proportional to the phase difference between the first and second signals . moreover , a logic high on the q bar output of the flip - flop 70 resets the flip - flop 80 forcing the q output of this flip - flop to a logic low . the logic low on the q output of the flip - flop 80 allows the flip - flop 70 to be responsive to the subsequent leading edge of the first signal 6 . this configuration allows the dual state phase detector 28 to be responsive to the leading edge transition , and not to be affected by the pulse width of the first and second input signals 6 and 4 . while the use of a single dual state phase detector 28 has been described , if desired to provide frequency steering of the dual state phase detector , on arrangement such as illustrated in my copending u . s . application ser . no . 357 , 912 , filed may 30 , 1989 , can be utilized . this application utilizes two dual state devices to provide extended range , the application is hereby incorporated by reference . | Should this patent be classified under 'Electricity'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | dc647100d80420258552ee328f23455201072908e26a581753347a0ddec49939 | 0.106934 | 0.103516 | 0.002975 | 0.031738 | 0.07373 | 0.072754 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | Does the content of this patent fall under the category of 'Human Necessities'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.490234 | 0.006104 | 0.300781 | 0.000051 | 0.320313 | 0.013245 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.357422 | 0.010986 | 0.376953 | 0.012451 | 0.28125 | 0.040283 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.355469 | 0.000572 | 0.376953 | 0.000007 | 0.28125 | 0.0065 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | Is this patent appropriately categorized as 'Fixed Constructions'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.28125 | 0.017944 | 0.106934 | 0.009399 | 0.230469 | 0.054932 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Should this patent be classified under 'Chemistry; Metallurgy'? | Does the content of this patent fall under the category of 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.3125 | 0.003937 | 0.214844 | 0.000043 | 0.192383 | 0.011353 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | Does the content of this patent fall under the category of 'Physics'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.490234 | 0.039063 | 0.306641 | 0.002625 | 0.320313 | 0.101074 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | Is 'Electricity' the correct technical category for the patent? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.285156 | 0.002716 | 0.106934 | 0.000116 | 0.230469 | 0.001503 |
null | in the practice of the present invention , a brass component of the type described which customarily comes into contact with water is first treated in a hot caustic wash . as used herein , the caustic wash is an aqueous solution of an alkali metal hydroxide and preferably sodium or potassium hydroxide having a ph above 10 , and preferably above 12 . in general , the concentration of alkali metal hydroxide in the aqueous solution is an amount sufficient to remove substantially all of the hydroxide - leachable lead from the brass part . in general , use can be made of caustic solutions containing from about 10 to about 50 percent alkali metal hydroxide , although higher and lower amounts of caustic may be used , depending somewhat on the treatment time desired . in general , the more concentrated the alkali metal hydroxide in solution , the shorter is the treatment time necessary to remove at least 50 percent of the leachable lead . another parameter affecting the treatment time for the caustic solution is the temperature . in general , higher temperatures favor shorter treatment times while lower temperatures generally necessitate longer treatment times . best results are obtained when the temperature of the caustic solution is at least 80 ยฐ f ., and preferably ranges from about 100 ยฐ f . to about 200 ยฐ f . it is also frequently desirable to employ ultrasonic agitation of the caustic bath or the parts therein to insure maximum contact between the caustic solution and the brass . good results are typically obtained when the entire caustic bath is subjected to ultrasonic agitation . for example , it has been found that , using ultrasonic agitation , nearly all of the hydroxide - leachable lead can be removed from the brass components in the first several minutes of treatment . good results are obtained , depending somewhat on the temperature , the concentration and the degree of agitation , when the treatment time ranges from about one minute to about 60 minutes . after the component has been treated with the hot caustic wash , it is then rinsed with water , and preferably deionized water , to remove any dirt adhering to the surfaces of the components as well as to remove excess alkali metal hydroxide and any lead present on the surface of the parts . the rinsing time can be varied within wide limits , but generally a rinse extending from about 0 . 5 to about 30 minutes is sufficient . thereafter , the brass component is treated with carboxylic acid to remove substantially all of the leachable lead remaining on the component . use is preferably made of a water soluble carboxylic acid containing from 1 to 8 carbon atoms and from 1 to 4 carboxyl groups . representative of such acids are acetic acid , propionic acid , butyric acid , iso - butyric acid , citric acid , and the like . the concentration of the acid in aqueous solution can be varied within relatively wide ranges , depending again on the temperature of the acid treatment and the duration of the acid treatment . good results are usually obtained when the concentration of the carboxylic acid ranges from about 0 . 01 to about 1 . 0m . once again , at least 50 percent of the acid - leachable lead is removed from the brass component during the first several minutes of treatment . in general , however it is preferred to employ acid treatment times ranging from about one minute to about 45 minutes . as will be appreciated by those skilled in the art , the use of additional treatment times is useful in the cleaning of the parts to remove deposits remaining from casting of the parts using well - known core casting techniques . best results are typically obtained when the acid employed is acetic acid , although citric acid likewise provides highly beneficial results . as with the caustic bath , it is also frequently desirable to employ ultrasonic agitation of the carboxylic acid bath or the parts therein to insure maximum contact between the carboxylic acid solution and the brass . good results are typically obtained when the entire carboxylic acid bath is subjected to ultrasonic agitation . it has been found that the combination of caustic followed by acid treatment removes substantially all of the leachable lead from the part . it has been found that the removal rate of lead can be up to two times greater in the caustic treatment step compared to that achieved for subsequent acid washing steps . as will be appreciated by those skilled in the art , both the caustic and acid treatment steps can either be carried out in a single step in which the brass component is contacted with either the caustic solution or acid solution . as an alternative , however , it is possible , and sometimes desirable , to use a series of caustic and / or acid treatment steps . it has been found that the use of the series of treatment steps has the advantage of providing increased rates of lead removal , particularly where the treatment solutions are more dilute . without limiting the invention as to theory , it is believed that the concentration driving force between the lead in the part and lead contained in the solution is greater when use is made of a series of caustic and / or acid treatment steps to thermodynamically drive the reactions . one of the advantages in the practice of the invention is that the sequence of caustic and acid treatment of the brass components exhibits no wholesale attack on the brass . on the contrary , the treatment process is limited primarily to lead removal , although there can be observed some removal of zinc during the caustic wash step . once again , without limiting the invention as to theory , the removal of zinc can be attributed to the solubility of zinc complexes at high ph and possible surface enrichment of zinc during casting of the parts . in the optional final step of the process , the components are treated with a phosphorus - containing acid , acid salt or salt derived from alkali metal , and preferably phosphoric acid . also suitable are alkali metal salts of phosphoric acid and alkali metal acid salts of phosphoric acid ( e . g ., trisodium phosphate , monosodium phosphate and disodium phosphate ). without limiting the invention as to theory , it is believed that the treatment with the carboxylic acid chemically etches the brass component , leaving a weak electrical charge . when that weakly charged brass component is rinsed with phosphoric acid , for example , most of the remaining residual trace amounts of lead , if any , are removed , and the brass component is passivated , with residual lead , if any , forming a relatively insoluble lead - phosphate . it has been found that insoluble lead phosphate is relatively impervious to the action of water . furthermore , the phosphate passivates the metal against corrosion , effectively minimizing any further leaching of metals from the brass component into water coming in contact with the brass component . that , in turn , assures that any water coming in contact with the treated brass component contains very low levels of lead , generally below 11 parts per billion and typically below 5 parts per billion of lead in water . as with the caustic and carboxylic acid bath , it is also frequently desirable to employ ultrasonic agitation of the phosphorus - containing acid bath or the parts therein to insure maximum contact between the phosphorus - containing acid solution and the brass . good results are typically obtained when the entire phosphorus - containing acid bath is subjected to ultrasonic agitation . in accordance with another alternative embodiment of the invention , it has been found advantageous , and particularly where the plumbing fixtures to be treated are formed from red brass , to employ a chemical milling pretreatment step by which surface metal is removed from the interior of such plumbing fixtures preparing the brass component for more effective removal of the leachable lead . as indicated , it is frequently preferred to employ a strong acid to remove surface metal from the interior of plumbing parts . various acids can be used for that purpose , although it is preferred that the acid not be of such a strength as to cause excessive metal removal . as will be appreciated by those skilled in the art , the metal removal is determined not only by the acid employed , but also by its concentration , the time of immersion and the temperature . in general , use can be made of mineral acids such as hydrochloric acid , sulfuric acid , or nitric acid , either alone , or in combination with organic acids and preferably carboxylic acids . it has also been found that performance of such acids can , in appropriate cases , be enhanced through the use of oxidizing agents , and most notably peroxides ( e . g ., h 2 o 2 ). it has been found that the use of such a chemical milling pretreatment step is particularly advantageous where , as a result of the casting operations , the interior of the plumbing fixtures undergoing treatment have a relatively high degree of surface roughness and residue . in the preferred practice of the invention , it is also frequently desirable to rotate the various parts undergoing treatment during the treating operation . for example , such rotation can be effected during the time that the part is undergoing treatment during either the caustic or acidic treatment steps to remove air pockets which may be formed within the interior of the parts undergoing treatment . thus the rotation of the parts during treatment ensures a more uniform treatment of the brass parts . having described the basic concepts of the invention , reference is now made to the following examples which are provided by way of illustration , and not by way of limitation , of the practice of the present invention . brass fixture components were treated by submerging in a sequence of chemical baths designed to leach lead from the components . fixtures were held on racks that allowed free flow of solution into each fixture . the baths were prepared in tanks with ultrasonic generators and electric heater coils as described below . the first bath contained 10 % sodium hydroxide and deionized water . two ultrasonic generators and one electric heater coil were installed . the temperature of the caustic solution was maintained at 150 deg . f . fixtures were submerged for half of the specified duration , lifted from the tank , rotated 180 degrees along the vertical axis and submerged for the remainder of the duration . the second bath was a water rinse at ambient temperature with no ultrasonics , however air agitation was used . fixtures were submerged for a period of approximately 1 minute . the third bath contained a 0 . 1m acetic acid pre - soak solution at ambient temperature . parts were submerged for approximately 1 minute . no ultrasonics were used , however air agitation was used . the fourth bath contained 0 . 1m acetic acid solution with four ultrasonic generators and two electric heater coils . bath temperature was maintained at 120 deg . f . fixtures were submerged in the bath for the specified duration then lifted out of the tank and rotated 180 degrees about the vertical axis . fixtures were again submerged for the remainder of the specified duration . the final three tanks were deionized water counter flowing rinses with air agitation used in the second tank and ultrasonics in the final tank with two ultrasonic generators and an electric heater coil . the final tank bath temperature was maintained at 140 deg . f . three yellow brass castings each with a cold mix volume of 0 . 085 liters were treated with the above procedure . castings were submerged for five minutes in a caustic bath , five minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 2 . 21 2 . 30 2 . 64 0 . 79 0 . 83 0 . 97 4 1 . 62 1 . 62 1 . 79 0 . 48 0 . 48 0 . 58 5 1 . 28 1 . 19 1 . 45 0 . 25 0 . 17 0 . 3710 0 . 85 0 . 84 1 . 02 - 0 . 16 - 0 . 17 0 . 0211 0 . 68 0 . 72 0 . 85 - 0 . 39 - 0 . 33 - 0 . 1612 0 . 65 0 . 70 0 . 65 - 0 . 43 - 0 . 36 - 0 . 4317 0 . 41 0 . 54 0 . 59 - 0 . 89 - 0 . 62 - 0 . 5318 0 . 26 0 . 27 0 . 29 - 1 . 35 - 1 . 31 - 1 . 2419 0 . 43 0 . 37 0 . 43 - 0 . 84 - 0 . 99 - 0 . 84average - 0 . 28 - 0 . 25 - 0 . 14mean - 0 . 23std dev 0 . 08q test statistic 0 . 97______________________________________ three red brass castings each with a cold mix volume of 0 . 116 l liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water and phosphoric acid . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 12 . 76 13 . 92 13 . 92 2 . 55 2 . 63 2 . 63 4 15 . 08 12 . 76 13 . 92 2 . 71 2 . 55 2 . 63 5 11 . 60 15 . 08 16 . 24 2 . 45 2 . 71 2 . 7910 8 . 93 15 . 08 11 . 60 2 . 19 2 . 71 2 . 4511 5 . 92 6 . 50 7 . 19 1 . 78 1 . 87 1 . 9712 5 . 57 6 . 03 6 . 15 1 . 72 1 . 80 1 . 8217 7 . 54 7 . 42 8 . 35 2 . 02 2 . 00 2 . 1218 19 . 72 7 . 08 5 . 92 2 . 98 1 . 96 1 . 7819 7 . 77 5 . 68 6 . 73 2 . 05 1 . 74 1 . 91average 2 . 27 2 . 22 2 . 23mean 2 . 24std dev 0 . 03q test statistic 10 . 10______________________________________ three red brass castings each with a cold mix volume of 0 . 116 liters were treated with the same procedure as above . castings were submerged for sixty minutes in a caustic bath , thirty minutes in an acetic acid bath and five minutes in the final rinse of deionized water . the castings were then tested with procedures required by nsf standard 61 , section 9 . the q statistic was then determined by formulas contained in nsf standard 61 , section 9 . ______________________________________ lead detected ug ! ln ugday 1 2 3 1 2 3______________________________________ 3 6 . 15 6 . 73 7 . 42 1 . 82 1 . 91 2 . 00 4 4 . 64 6 . 73 4 . 99 1 . 53 1 . 91 1 . 61 5 4 . 18 6 . 15 4 . 99 1 . 43 1 . 82 1 . 6110 3 . 02 3 . 71 15 . 08 1 . 11 1 . 31 2 . 7111 2 . 44 3 . 25 3 . 02 0 . 89 1 . 18 1 . 1112 2 . 20 2 . 90 3 . 25 0 . 79 1 . 06 1 . 1817 2 . 32 3 . 71 3 . 02 0 . 84 1 . 31 1 . 1118 5 . 10 2 . 09 4 . 87 1 . 63 0 . 74 1 . 5819 1 . 86 4 . 06 2 . 44 0 . 62 1 . 40 0 . 89average 1 . 18 1 . 40 1 . 53mean 1 . 37std dev 0 . 18q test statistic 6 . 26______________________________________ it will be understood that various changes can be made in the details of procedure , formulation and use without departing from the spirit of the invention , especially as defined in the following claims . | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | 0.25 | 182bb6054f01a3b07a8770cbb53a25fe59b22685ef41a0c754429518d422d34f | 0.285156 | 0.078125 | 0.106934 | 0.433594 | 0.230469 | 0.155273 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Is 'Electricity' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Human Necessities'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.710938 | 0.004211 | 0.558594 | 0.000169 | 0.398438 | 0.010986 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Is 'Electricity' the correct technical category for the patent? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.710938 | 0.00592 | 0.558594 | 0.00383 | 0.398438 | 0.016968 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Does the content of this patent fall under the category of 'Electricity'? | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.851563 | 0.001755 | 0.75 | 0.000336 | 0.597656 | 0.001648 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Does the content of this patent fall under the category of 'Electricity'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.851563 | 0.000149 | 0.75 | 0.000002 | 0.597656 | 0.000519 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Should this patent be classified under 'Electricity'? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.738281 | 0.007568 | 0.609375 | 0.001701 | 0.349609 | 0.013245 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Is this patent appropriately categorized as 'Electricity'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.683594 | 0.002045 | 0.328125 | 0.001328 | 0.304688 | 0.007355 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Is 'Electricity' the correct technical category for the patent? | Is 'Physics' the correct technical category for the patent? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.710938 | 0.007568 | 0.558594 | 0.001701 | 0.398438 | 0.014526 |
null | before any embodiments of the invention are explained , it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings . the invention is capable of other embodiments and of being practiced or of being carried out in various ways . also , it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting . the use of including , comprising , or having and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items . fig1 illustrates an electrical device 20 embodying the invention . in the preferred embodiment , the device 20 is a self - contained , battery operated medical device such as a holter monitor , or telemetry - based patient monitoring transmitter . however , the invention is applicable to any battery operated electrical device . the electrical device 20 includes a generally rectangular housing 28 . the housing 28 includes at least one sidewall 30 defining a cavity 31 ( see fig3 ) for holding first , second , and third batteries 72 , 76 , and 80 ( see fig7 ), and for holding conducting members 33 a , 33 b , 33 c , 33 d , and 33 f ( see fig3 ) to electrically connect the batteries 72 , 76 , 80 in series , and transfer electrical power from the batteries 72 , 76 , 80 to an electrically powered machine or apparatus 82 ( shown schematically in fig8 ), also preferably enclosed within the housing 28 . contact members 33 b and 33 c are preferably formed from a single piece of metal or other electrically conductive material so that they are electrically connected to each other . referring to fig2 the sidewall 30 also defines a circular opening 32 extending through the sidewall 30 and communicating with the cavity 31 . the device 20 includes a sealing member 34 that fits within the circular opening 32 to close and seal the cavity 31 . in the preferred embodiment , the sidewall 30 defining the opening 32 is threaded , and the sealing member 34 is threaded into the opening 32 along an insertion axis 40 to seal the housing 28 . the sealing member 34 includes a spring contact 33 e and a contact member 35 connected to the spring contact 33 e so that when the sealing member 34 is inserted in place in opening 32 , contact member 33 d is electrically connected to spring contact 33 e . in other embodiments , the sealing member 34 can be inserted into the opening 32 along the axis 40 and frictionally engages the housing 28 surrounding the opening 32 to seal the housing 28 . in such a construction , a second sealing member ( not shown ), such as , for example , an o - ring or a gasket , mounts to the sealing member 34 and frictionally engages the housing 28 in a position between the sealing member 34 and the housing 28 to seal the housing 28 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . in another embodiment , the second sealing member is mountable to the housing 28 in a position between the housing 28 and the sealing member 34 , such that liquid cannot penetrate past the second sealing member and enter into the housing 28 . referring to fig3 the electrical device 20 includes a base portion or support member 44 slidably supported by the housing 28 . as viewed in the orientation shown in fig3 the support member 44 has a generally upright portion 48 and a generally horizontal lip or support portion 52 that extends into the cavity 31 defined by the housing 28 . the electrical device 20 also includes a track 60 that is mounted to the housing 28 . the support member 44 is slidably mounted to the track 60 and can slide between a first position and a second position . in the preferred construction , the track 60 is angled , so that the support member 44 moves to the left ( as shown in fig3 ) as the support member 44 slides down and so that the support member 44 moves to the right ( as shown in fig3 ) as the support member 44 slides up . the support member 44 is in the first position at the top of the track 60 ( see fig3 ) and in the second position at the bottom of the track 60 ( see fig7 ). the electrical device 20 optionally includes a biasing member 64 supported between the housing 28 and the support member 44 . the biasing member 64 biases the support member 44 toward the first position ( as seen in fig3 ). the electrical device 20 also includes a battery stop 68 that is supported by the housing 28 and protrudes into the cavity 31 . the battery stop 68 limits the insertion of batteries 72 , 76 , 80 into the cavity 31 . referring to fig4 the electrical device 20 and the first battery 72 are illustrated . the first battery 72 inserts into the cavity 31 of the electrical device 20 through the opening 32 along the insertion axis 40 . the second and third batteries 76 and 80 are inserted likewise . after the batteries 72 , 76 , 80 are inserted into the cavity 31 , the sealing member 34 is threaded into the housing 28 to seal the housing 28 . referring to fig5 the electrical device 20 is illustrated with the first battery 72 inserted through the opening 32 and into the cavity 31 . the first battery 72 rests on the support portion 52 transverse to the insertion axis 40 and biases the support member 44 slightly downward along the track 60 . referring to fig6 the electrical device 20 is illustrated with the first and second batteries 72 and 76 inserted through the opening 32 and into the cavity 31 . the second battery 76 rests on top of the first battery 72 and biases the support member 44 downward along the track 60 , further than the first battery 72 alone . both the first and second batteries 72 and 76 rest transversely to the insertion axis 40 . as described above and illustrated in fig5 and 6 , the batteries 72 and 76 self - orient themselves as a result of gravity so that they rest upon the support portion 52 after insertion . if the electrical device 20 is in a different orientation with respect to the gravitational field , or is being used in a weightless environment such as outer space , the batteries 72 and 76 can be moved clear of the opening 32 and toward the support portion 52 by other means , such as , but not limited to shaking , accelerating , or jerking the electrical device 20 . referring to fig7 ., the electrical device 20 is illustrated with the first , second , and third batteries 72 , 76 , and 80 inserted through the opening 32 and into the cavity 31 . as the third battery 80 is inserted through the opening 32 and into the cavity 31 , the third battery 80 contacts the transversely aligned second battery 76 . the third battery 80 biases the first and second batteries 72 and 76 downward against the support member 44 and biasing member 64 . the biasing member 64 exerts a force on the support member 44 and is chosen such that the force exerted by the third battery 80 upon insertion into the cavity 31 , easily overcomes the force exerted by the biasing member 64 on the support member 44 . the force exerted by the biasing member 64 is also chosen to be light enough so that a pinch force exerted on the third battery 80 is easily overcome by gravity or a gentle tap when the batteries 72 , 76 , 80 are removed from the electrical device 20 . the pinch force is the force exerted by the biasing member 44 on the batteries 72 , 76 , 80 upon the insertion of the first , second , and third batteries 72 , 76 , and 80 into the cavity 31 . the third battery 80 is pushed into the cavity 31 until contact is made with the battery stop 68 , at which point , the first , second , and third batteries 72 , 76 , and 80 are aligned generally parallel to the insertion axis 40 and the support member 44 is at the bottom of the track 60 in the second position . the sealing member 34 is threaded into the housing 28 and seals the batteries 72 , 76 , 80 in the electrical device 20 . the embodiments described above and illustrated in the figures are presented by way of example only and not intended as a limitation upon the concepts and principles of the present invention . as such , it will be appreciated by one having ordinary skill in the art that various changes in the elements and their configuration and arrangement are possible without departing from the spirit and scope of the present invention . various features of the invention are set forth in the following claims . | Is this patent appropriately categorized as 'Electricity'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 64f721cee5a38c9f82615cad90fd32e5064c347d597ed9a0c4ad8c8cce8fc1c0 | 0.683594 | 0.09668 | 0.328125 | 0.066406 | 0.304688 | 0.109863 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Is 'Human Necessities' the correct technical category for the patent? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.016968 | 0.019409 | 0.002396 | 0.000278 | 0.018799 | 0.007568 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.037354 | 0.002548 | 0.008606 | 0.000132 | 0.04541 | 0.003479 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Should this patent be classified under 'Performing Operations; Transporting'? | Is 'Textiles; Paper' the correct technical category for the patent? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.016968 | 0.002319 | 0.002396 | 0.00004 | 0.018799 | 0.014526 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Should this patent be classified under 'Fixed Constructions'? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.055908 | 0.088867 | 0.011658 | 0.125 | 0.061768 | 0.140625 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended 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 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.060059 | 0.02063 | 0.011658 | 0.001549 | 0.061768 | 0.021606 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Should this patent be classified under 'Physics'? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.042725 | 0.098145 | 0.026733 | 0.005554 | 0.046631 | 0.061768 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Electricity'? | 0.25 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.042725 | 0.025513 | 0.026733 | 0.000096 | 0.046631 | 0.001328 |
null | the preferred embodiment of the invention is shown in and described with reference to fig1 to 8 , and will be described first . fig1 diagrammatically illustrates a radial arm saw 20 according to the present invention and comprising a saw assembly 22 , a saw table frame 24 , and a wall support 26 securely mounted on a wall 28 . the wall 28 may be a brick or block wall or a wooden framed wall of a workshop or other room in a building . the saw assembly 22 comprises a saw unit 30 having a circular saw blade 32 and a handle 34 . the saw unit 30 is suspended by a carriage 36 from a radial arm 38 and along which the saw unit 30 is translatable by grasping and moving the handle 34 . the radial arm 38 is mounted on and cantilevered from the upper end of an upright , vertical column 40 the lower end of which is clamped in a socket 42 . the radial arm 38 can be moved up and down the column 40 by means of a handle 44 for adjusting the height of the saw blade 32 . the radial arm 38 can be pivoted about the column 40 in horizontal planes and locked in any selected position by a lever 46 . the frame 20 comprises a frame structure 48 having mounted thereon a horizontal work table 50 comprising a front fixed section 52 , removable middle and rear sections 54 , 56 , with an upstanding fence 58 removably disposed between the sections 54 , 56 . the sections 54 , 56 and the fence 58 are forwardly clamped against the rear edge of the fixed front section 52 . the frame structure 48 is pivotally mounted between upstanding side plate extensions 60 of the wall support 26 on bolts 62 , one on each side . the wall support 26 has a hollow box portion 64 from which the extensions 60 extend upwardly from adjacent the front thereof . the rear of the box portion 64 has a vertical leg 66 securely attached to each side thereof . each leg 66 has a pair of brackets 68 , one at the top and the other partway along its length , which are securely fixed to the wall 28 by screws 70 . at the lower end of each leg 66 is provided a plumb adjuster 72 and a height adjuster 74 which are adjusted to compensate for any variations in the wall 28 and the floor 75 so that the lower end of each leg 66 firmly engages both the wall 28 and the floor 75 . it should be noted that the brackets 68 and the adjuster 72 space the leg 66 a short distance from the surface of the wall 28 ; this also helps in accommodating any variations in the surface of the wall 28 . a pair of foldway legs 76 , one on each side , are pivotally connected at their upper ends by pivot bolts 78 to opposite sides of the frame structure 48 adjacent the front thereof . a bracing strut 80 is pivotally connected at one end , its forward end , to an upper portion of each leg 76 by a pivot bolt 82 . both the strut 40 and the leg 76 are of u - shaped channel section , and the forward end of the strut 80 is located inside the leg 76 . the rear end of each bracing strut 80 is pivotally attached to the wall support 26 by a pivot bolt 84 located adjacent the top of the box portion 64 just rearwardly of the upstanding side plate extension 60 . as can be seen , the rear end of the strut is curved upwardly , and the remainder of the strut 80 extends forwardly and upwardly at a small angle to the horizontal . the bottom of each leg 76 is provided with an adjustable foot 86 which telescopically extends upwardly inside the leg 76 ( as shown in broken lines ) and is secured in the adjusted position by a locking bolt 88 . a locking sleeve 90 of rectangular tubular cross section is a loose sliding fit on the upper portion of each leg 76 , and is located between the pivot bolts 78 and 82 which may act as stops to limit the sliding travel of the sleeve 90 . as can be seen in fig1 the lower edge of the sleeve 90 rests on the extended strut 80 and is thereby spaced a short distance d above and from the pivot bolt 82 . at its upper forward edge the sleeve 90 is provided with a forwardly extending tab handle 92 . from the operative position shown in fig1 the radial arm saw 20 can be folded away into a stored position adjacent the wall 28 . first , the column socket 42 is unlatched and pivoted about a horizontal axis 91 until the column 40 lies along the back edge of the table 50 , the radial arm 38 lies along the far side of the table 50 , and the saw unit 30 extends downwardly partway through the table 50 to the position shown in fig3 and as will be described more fully later . secondly , the front of the table part 52 is then grasped in one or both hands and raised upwards and backwards to pivot the frame structure 48 upwardly about the pivot bolt 62 . the table part 52 is so pivoted until it reaches the broken line position shown in fig1 with its lower surface now in the vertical plane v . during this pivoting of the table 50 and frame structure 48 , each leg 76 pivots about its pivot bolt 78 and hangs therefrom vertically , the strut 80 pivoting upwardly about its pivot 84 and also pivoting relative to the leg 76 about the pivot bolt 82 . the final vertical position of the leg 76 is shown in broken lines in fig1 and as can be appreciated , in this stored position the strut 80 becomes nested inside the leg 76 . as the leg 76 reaches its stored position and the strut 80 folds inside the leg , the locking sleeve 90 is free to slide down the leg 76 until arrested by the pivot bolt 82 . in this position , the locking sleeve 90 prevents downward return pivoting of the table 50 , as will be described in more detail later , and so locks the radial arm saw in the stored position . during the folding ( and subsequent unfolding ) of the table 52 from the extended position shown in fig1 full lines to the stored position shown in broken lines , the arcs along which various parts move are shown in broken lines . the front edge of the table 50 moves along a circular arc 94 centered on the axis of pivot bolt 62 . the pivot 78 at the top of the leg 76 moves along a circular arc 96 also centered upon the axis of pivot bolt 62 . the pivot bolt 82 , connecting the strut 80 and the leg 76 , moves along a circular arc 98 centered upon the axis of pivot bolt 84 at the rear end of the strut 80 . the adjusting foot 86 at the bottom of the leg 76 moves along an arc 100 so that in the stored position the adjustable foot 86 is located outside and just above the bottom of the box portion 64 of the wall support 26 as shown in broken lines . thus , it will be appreciated , that in the stored position , the leg 76 , the frame structure 48 , the table 50 , and the saw assembly 22 are all positioned above the bottom of the box portion 64 and also are all positioned rearwardly of the front face of the box portion 64 . the box portion 64 is hollow and is bounded by side plates , a top , a bottom , and a back . the front of the hollow box portion 64 is closed by a door 102 ( shown in broken lines in fig1 ) which is pivoted at its lower edge to the side plates of box portion 64 by pivot hinges 104 . when the radial arm saw is in the stored position , the door 102 is readily accessible and can be pivoted downwardly and forwardly to store in or remove from the inside of the box portion 64 accessories , tools etc . usable in association with the radial arm saw . in the operative position of the radial arm saw shown in fig1 the frame structure 48 is securely supported by the wall support 26 at the rear and the pair of legs 76 at the front with the bracing struts 80 therebetween . however , if desired , means may be provided to lock or latch the frame structure 48 in its operative , extended position . for example , a locking bolt 106 can be inserted through each side plate extension 60 into the frame structure 48 , such bolt 106 being manually removed before pivoting the frame structure 48 to the stored position . alternatively , a releasable latch may be provided between each side plate extension 60 and the associated side of the frame structure 48 . at a location between the pivot bolts 78 and 82 , and just above the sleeve 90 , the pair of legs 76 are rigidly secured together by a handle bar 107 which extends forwardly from each leg 76 just above the tab handle 92 on each sleeve 90 . the purpose of the handle bar 107 is to facilitate unfolding the table 50 and frame structure 48 from the stored position to the operative position . to perform this unfolding operation , the handle bar 107 is grasped on each side by each hand , a finger of each hand used to engage the tab handle 92 of each sleeve 90 and raise that sleeve to unlock each leg 76 from its associated strut 80 , and then the table unit pivoted downwardly using the handle bar 107 . once this downward pivoting has commenced , the fingers can release each tab handle 92 as each strut 80 becomes separated from inside the associated leg 76 . in a desirable modification of the locking sleeve arrangement , the head and nut of the pivot bolt 82 may be recessed in the sides of the leg 76 and / or otherwise shaped and dimensioned so that the sleeve 90 passes over the pivot bolt 82 in the folded - away position of the saw table , each sleeve 90 then in such position sliding all the way down the leg 76 until it is stopped by the curved portion of the strut 80 extending rearwardly out of the leg 76 . with this modification , to unfold the saw table the sleeves 90 are first slid upwardly to a position above the pivot bolts 82 and held in this raised position by a finger of each hand while the ends of the bar handle 107 are then grasped to lower the saw table . it should be noted that the pivot bolt 84 is disposed rearwardly of the frame structure pivot bolt 62 so that the pivot bolt 84 will not interfere with the vertical stored position of the leg 76 ; and the rear end of the strut 80 is curved to accommodate this . fig2 is a diagrammatic front elevational view of the radial arm saw and shows the electric motor 108 of the saw unit extending to the opposite side of the radial arm 38 to the saw blade 32 . the two parallel legs 76 can be seen connected together by the handle bar 107 . the lower portion of the right hand front leg 76 has been broken away to show the bottom of the right hand rear leg 66 of the wall support 26 . the four brackets 68 can be seen extending sideways outside the legs 76 and 66 . the upstanding side plate extensions 60 can be seen spaced outwardly from the frame structure 48 with the two pivot bolts 62 bridging the gaps therebetween . the downwardly pivoting door 102 of the box portion 64 is provided with a handle 110 which can also be used to lock the door in the closed position . an on / off switch 105 for the motor 108 is located in the front face of the radial arm 38 . fig3 is a diagrammatic top plan view of the saw table , with parts omitted and a portion broken away to show more details of the frame structure 48 . the front portion 52 of the table is screwed to the frame structure 48 . the middle portion 54 , the fence 58 , and the rear portion 56 of the table top are clamped by clamps 112 against the rear edge of the fixed portion 52 . the clamps 112 may be tightened and loosened by rotating handles 114 . by loosening the handles 114 , the back portion of the table top comprising the parts 54 , 58 and 56 can be removed . after removal of the parts 54 , 58 and 56 , the saw assembly 22 can be pivoted to the inoperative position shown in broken lines . to reach this position , the column 40 and socket 42 pivot about the horizontal pivot bolt 115 ( shown in broken lines ) until the column 40 and the radial arm 38 lie outside the saw table in substantially the plane thereof . during the final portion of this pivoting , the motor 108 enters and is partly housed in a cavity 109 between members of the frame structure 48 , this cavity 109 being exposed when the table parts 54 , 58 , 56 are removed . after the saw unit 22 has been pivoted to the inoperative position shown in fig3 the saw table and frame structure 48 are then ready to be pivoted upwardly and backwardly to the stored position indicated in broken lines in fig1 . i it will thus be appreciated that in the stored position , the saw assembly , particularly the saw blade 32 , is positioned between the wall 28 and the now upright saw table 50 and frame structure 48 , so shielding the saw assembly and the saw blade from access and accidental interference . also , the on / off switch 105 of the saw will be adjacent the top of the stored radial arm so pointing upwards towards the ceiling ; in this position the on / off switch is most inaccessible . fig4 diagrammatically shows a section on the line 4 -- 4 in fig1 with the sleeve 90 resting on top of the bracing strut 80 . the u - shaped channel form of the leg 76 inside the sleeve 90 is clearly shown as is the tab handle 92 extending from the front of the sleeve 90 . fig5 is a diagrammatic section on the line 5 -- 5 in fig1 and shows the u - shaped channel sectioned bracing strut 80 nested inside the leg 76 . in this position the sleeve 90 has dropped down over the upper end of the nested strut 80 so preventing the strut 80 from pivoting relative to the sleeve 90 or the leg 76 . to render this locking position of the sleeve 90 more effective , a cutout 116 is provided in the lower portion of each side of the sleeve to accommodate the head of the pivot bolt 82 and its nut 118 and allow the sleeve 90 to slide partially past the pivot bolt 82 . each cutout 116 extends approximately halfway up the height of the sleeve 90 , as shown in fig1 . fig6 and 8 illustrate a latch mechanism 120 for locking the column 40 in the upright , vertical operative position ( fig6 and 7 ), and also for locking the column 40 in the horizontal inoperative position ( fig8 ). an arm 122 extends at right angles to the socket 42 from one side thereof below the pivot 115 ( fig7 ) about which the socket 42 is pivotal . in the upright vertical position of the column 40 , an arm assembly 126 carrying an l - shaped bracket 124 is resiliently biased about a pivot 128 to cause the base of the l - shaped bracket 124 to engage over the free end of the arm 122 and latch the socket 42 in its vertical position -- as shown in fig7 . to pivot the column 40 to the inoperative position , the l - shaped bracket 124 is manually pivoted clockwise in fig7 to unlatch the arm 122 , so allowing the socket 42 to be pivoted counter - clockwise to its inoperative , stored horizontal position . when the l - shaped bracket 124 is released , its upper end is resiliently biased counter - clockwise to engage the base of the socket 42 and also engage under a ramp - like detent 130 extending from the base of the socket 42 to latch the socket 42 and column 40 in the horizontal collapsed position . to again erect the column 40 to its vertical position , the bracket 124 is manually moved clockwise against the spring bias to disengage the bracket 124 from the detent 130 so allowing the column 40 to be pivoted clockwise . this column latching arrangement 120 is more fully disclosed in u . s . pat . no . 4 , 523 , 504 in which it is illustrated in fig9 and 11 thereof . also , the manner of pivoting the saw assembly into and around the frame structure of a radial arm saw to collapse such for storage is more fully described and illustrated in u . s . pat . no . 4 , 523 , 504 the whole disclosure of which is hereby incorporated herein by reference . fig9 and 11 illustrate a second embodiment of the present invention . in this embodiment the saw table 50 , the saw unit 30 , the radial arm 38 , and the column 40 are the same as previously described with respect to the previous embodiment . however , the base of the column socket 140 is provided with a flange which is mounted on the top of a box - like wall support 142 and secured thereto by four bolts 144 ( only two of which can be seen ). the box - like wall support 142 is hollow to form a storage compartment and has a downwardly pivoting front door similar to that previously described in relation to fig1 and 2 . the box - like support 142 is mounted on and secured to the wall 28 by four screws 145 ( two of which are shown in broken lines ) which are driven home into the wall 28 from inside the support 142 . the saw table 50 is supported on a frame structure 146 which is provided at its rear lower edge with a pair of downwardly extending lugs 148 each of which is pivotally mounted on a side of the wall support 142 by a pivot bolt 150 . a bracing strut 152 comprising two part - struts 154 and 156 is pivotally attached at its lower end to the wall support 142 by a pivot 158 , spaced below the pivot 150 , and at its upper end the strut 152 is pivoted to the side of the frame structure 146 adjacent the front thereof by a pivot bolt 160 . the two strut parts 154 , 156 are pivoted together at 162 . a releasable latch means may be provided to prevent the strut parts 154 and 156 pivoting relative to each other when in the supporting position of fig9 ; this releasable latch means is schematically shown and identified by the reference numeral 164 . alternatively , or in addition , one of the strut parts 154 , 156 could be provided with a flange at one edge and abutting the other strut part to prevent the bracing strut 152 folding and moving the pivot 162 upward under the weight of the saw table 50 and the frame structure 146 . a releasable latch may be provided between the wall support 142 and the frame structure 146 to releasably lock the frame structure 146 in the extended , horizontal operative position shown in fig9 ; such a releasable latch is schematically illustrated by the broken line 166 . fig1 illustrates the stored position of the radial arm saw ; this position has been obtained from fig9 by releasing the lever 46 , pivoting the radial arm 38 on the column 40 until parallel to the wall 28 , locking the radial arm 38 in this position with the lever 46 , and then releasing the latch 164 with movement of the pivot 162 downwards to enable the saw table 50 and frame structure 146 to be pivoted downwardly about the pivot 150 to extend downwardly in a vertical position in front of the wall support 142 . the storage position of the saw table 50 and frame structure 146 is shown in solid lines in fig1 and broken lines in fig9 . the extended operative position of the saw table and frame structure is shown in solid lines in fig9 and broken lines in fig1 . the front edge of the saw table 50 moves through a circular arc 168 about the axis of the pivot 150 when moving between the operative and stored positions . as will be appreciated , the surface of the saw table 50 lies in a horizontal plane h 1 in the extended operative position , and in a vertical plane v 1 in the stored position . it will also be appreciated that there is a pivot 150 on each side of the wall support 142 , and also a pair of bracing struts 152 one on each side of the frame structure . fig1 is a top plan view of this second embodiment viewed along the line 11 -- 11 in fig9 . in broken lines the radial arm 38 and saw unit 30 are shown swung counter - clockwise about the vertical column 40 to nearly the stored position shown in fig1 . during swinging movement of the saw unit 30 to and from the stored position of fig1 , the radially outer end of the radial arm 38 moves along an arc 170 centered on the vertical axis of the column 40 . a third embodiment of the present invention is illustrated in fig1 and 13 . fig1 shows the radial arm saw in the operative position with the saw table 50 extended . fig1 shows the radial arm saw in the stored position with the saw table 50 folded upwardly to a vertical position and the column 40 , radial arm 38 , and saw unit 30 stored between the saw table 50 and the wall 28 . in this embodiment , the wall support 176 is similar to that in the previous embodiment except it has a pair of upstanding lugs 182 at the top front edge . each lug 182 supports a pivot 184 on which the frame structure 180 of the saw table is pivotally mounted . the socket 172 of the column 40 is provided with a base flange 174 and a front flange 178 . the base flange 174 is mounted on the top of the box - like wall support 176 and releasably secured thereto by four machine screws 175 . the forward flange 178 is releasably secured to the rear edge of the frame structure 180 by machine screws 179 . thus , in the operative position shown in fig1 , the saw table 50 and its frame structure 180 are cantilevered forwardly from the wall support 176 and immoveably secured in this position to the wall support via the flanges 178 and 174 of the socket 172 . in this operative position the top of the saw table 50 lies in a horizontal plane h 2 . to move the radial arm saw into the stored position shown in fig1 , the machine screws 175 and 179 are removed ; then the saw unit and column 40 lifted up and stored on the wall support 176 with the socket 172 and column 40 lying along the top of the wall support 176 , and with the saw blade guard of the saw unit 30 being positioned adjacent the wall 128 . the removable rear portions of the saw table 50 are now removed , i . e . the parts 54 , 56 , and 58 , and placed on top of the wall support 176 in the space between the column and radial arm unit 40 , 38 and the wall 28 , as illustrated in fig1 . the saw table 50 and frame structure 180 are then pivoted upwardly about the pivot 184 until the surface of the saw table 50 lies in a vertical plane v 2 . during this upward pivoting of the saw table 50 , the end of the motor 108 extending away from the wall 28 enters into and is stored in a recess in the frame structure 180 exposed by removal of the rear portion of the saw table 50 ( similarly as described with references to fig3 ). when the frame structure 180 has reached the vertical position shown in fig1 , it is latched in position by latch means operative between the wall support 176 and the frame structure 180 as indicated schematically by the broken line 186 . in the embodiment of fig1 to 8 , the removable rear parts 54 , 56 and 58 of the saw table 50 can , in the stored position of the radial arm saw , also be stored on top of the wall support between the wall 28 and the column 40 in a similar manner to that shown in fig1 . the above described embodiments , of course , are not to be construed as limiting the breadth of the present invention . modifications , and other alternative constructions , will be apparent which are within the spirit and scope of the invention as defined in the appended claims . | 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 | 810eb3526057886847eb706156780c0f0833ba7da49b76314eddc5f2b4d61a13 | 0.042725 | 0.147461 | 0.026733 | 0.033691 | 0.046631 | 0.098145 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.006897 | 0.005066 | 0.003372 | 0.00007 | 0.043945 | 0.001411 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.02002 | 0.214844 | 0.007111 | 0.081543 | 0.063477 | 0.151367 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.006897 | 0.014954 | 0.003372 | 0.000969 | 0.043945 | 0.007111 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is 'Textiles; Paper' the correct technical category for the patent? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.006897 | 0.000038 | 0.003372 | 0.000007 | 0.043945 | 0.000336 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.024048 | 0.023315 | 0.014038 | 0.022339 | 0.10498 | 0.015442 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Should this patent be classified under 'Physics'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.024048 | 0.031982 | 0.014038 | 0.001869 | 0.10498 | 0.010986 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Should this patent be classified under 'Electricity'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.024048 | 0.016968 | 0.014038 | 0.002975 | 0.10498 | 0.00008 |
null | referring now to the drawings , and in particular to fig1 load station 10 is shown supporting ammunition 11 which is transferred from storage via ammunition hoist tube 12 . cradle 14 pivots about trunnion support 16 until fully engaged by load station 10 . fig3 is a cross sectional view showing the engagement of cradle 14 with load station 10 . ammunition 11 is transferred from load station 10 to cradle 14 using cams and hydraulic means which cooperate to transfer and secure ammunition 11 in cradle 14 . turning now to fig2 a side view of cradle 14 in a horizontal orientation is shown . cradle 14 is mechanically moved from a substantially vertical position to a position within the gun recoil slide 22 , concentric to the gun tube 24 . crown gear 15 on cradle 14 mates with drive motor 20 . cradle 14 , including drive assembly 17 , stows within gun recoil slide 22 and is disposed coaxial with gun tube 24 . a plurality of continuous rails 26 are installed to provide a transfer mechanism for ammunition . fig4 is a sectional view of the preferred embodiment of the present invention . rammer pawls 28 and 28 &# 39 ; are attached to chain 34 . drive motor 20 drives rammer sprocket 36 and idler sprocket 36 &# 39 ;. fig5 a and 5b show springs 48 , pawl sensor 50 and latch 52 . pawl sensor 50 is a proximity switch and mounts on the back of cradle 14 as shown . the figures further show the structural organization of the flick rammer latch mechanism such as tapered flats 54 at the end of the drive shaft 55 . fig6 shows switch 60 mounted on a bracket . switch 60 confirms the engagement of latch 52 with shaft 55 . the discussion hereinabove briefly discloses the structural organization of some of the most important elements of the present invention relative to the preferred embodiment . the following discussion relates to the operation and cooperative performance of the elements of the present invention . the flick rammer method and device disclosed herein is the final stage in the transfer of ammunition from a storage compartment to a gun tube . referring now to fig1 - 6 , ammunition ( two - piece ) 11 is first transferred into load station 10 via ammunition hoist tube 12 . cradle 14 pivots downward about trunnion centerline 16 until fully engaged by load station 10 . after the full engagement of cradle 14 , load station 10 transfers ammunition 11 . the ammunition 11 is positively received and stored in cradle 14 . thereafter , cradle 14 pivots upwards until its center line is concentric with the gun tube 24 . as a result of this concentric alignment with gun tube 24 , cradle 14 engages gun recoil slide 22 . at this point in time , hydraulic motor 20 is activated to thereby initiate rammer sprocket 36 . accordingly rammer pawls 28 and 28 &# 39 ;, which are attached to chain 34 , are mobilized to push ammunition 11 forward into gun tube 24 . the peak rammer pawl velocity is controlled by the gun &# 39 ; s control system , based on the current gun elevation angle to assure that the ammunition will be fully seated and latched within the gun tube chamber . the rammer pawl stroke is fixed so that when one rammer pawl stroke is complete , second and consecutive rammer pawl is in position for the next ram . a detailed operation of the present invention is disclosed with reference to fig5 a , 5b and 6 ; a section through drive assembly 17 mounted to the back of cradle 14 is shown ( also see fig2 ). crown gear 15 engages drive motor 20 . further , the lower end of crown gear 15 is a right angle bevel gear connected to the rammer sprocket 36 . this arrangement enables drive motor 20 to turn / drive rammer sprocket 36 . it should be noted that similar or equivalent arrangements may be used to drive rammer sprocket 36 . further , referring to fig6 springs 48 are structured to push latch 52 . when latch 52 is pushed upwards it engages tapered flats 54 at the end of the drive shaft 55 thus preventing shaft 55 from rotating . latch 52 is automatically disengaged when cradle 14 is in the ramming position within gun recoil slide 22 . when cradle 14 engages gun recoil slide 22 a surface of recoil slide 22 pushes or bears downwards thereby unlatching the sprocket 36 and the chain 34 assembly ( also see fig4 ). latch 52 will not be disengaged until crown gear 15 has securely meshed with the mating crown gear of drive motor 20 . as indicated hereinabove , proximity switch 60 monitors latch 52 . proximity switch 60 reads switch activator ( not shown ) which is mounted adjacent to latch 52 . the location of rammer pawls 28 and 28 &# 39 ; is monitored by pawl sensor 50 . further , switch 60 signals when drive shaft 55 is securely latched . additionally , a resolver ( not shown ) is mounted on drive motor 20 . the resolver is initiated when rammer pawl 28 &# 39 ; is sensed by pawl sensor 50 and when drive shaft 55 is confirmed latched . accordingly , the present invention provides a rammer mechanism which operates in cooperation with the ammunition transfer gun system . it enables the loading of a two - piece ammunition in a gun tube and provides a complete material handling system wherein the ammunition is automatically transferred from storage into the gun tube . although the best mode contemplated for carrying out the present invention has been herein shown and described , it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention . | Should this patent be classified under 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | 0.25 | 5e0ee48a70af276a966c8b52c72f6356b5aa73a4c91aa26e641682f481f1711b | 0.006897 | 0.099609 | 0.003372 | 0.037842 | 0.043945 | 0.07373 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Human Necessities'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.149414 | 0.039551 | 0.15625 | 0.000216 | 0.094238 | 0.031738 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Is this patent appropriately categorized as 'Physics'? | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.226563 | 0.09668 | 0.316406 | 0.125 | 0.246094 | 0.183594 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Is this patent appropriately categorized as 'Physics'? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.226563 | 0.004059 | 0.316406 | 0.000035 | 0.246094 | 0.001595 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Should this patent be classified under 'Physics'? | Does the content of this patent fall under the category of 'Textiles; Paper'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.149414 | 0.002625 | 0.15625 | 0.000028 | 0.094238 | 0.02002 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Should this patent be classified under 'Physics'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.149414 | 0.048828 | 0.15625 | 0.010681 | 0.094238 | 0.074707 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.141602 | 0.018555 | 0.018799 | 0.024048 | 0.123535 | 0.070801 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Should this patent be classified under 'Physics'? | Should this patent be classified under 'Electricity'? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.149414 | 0.000645 | 0.15625 | 0.000085 | 0.094238 | 0.000296 |
null | please refer to fig1 to fig4 for a first embodiment of the present invention . the single - arm pedal assembly , which can be horizontally placed on the floor , for a percussion instrument of the present embodiment includes two frames 1 , 1 โฒ, a first main axle 2 , a second main axle 2 โฒ, a first linking element 3 , a second linking element 3 โฒ, two pedals 4 , 4 โฒ, two transmission elements 5 , 5 โฒ, a first resilient means 6 , a second resilient means 6 โฒ, a secondary axle , a clamping element 8 , a linkage member 9 and two hammers 10 , 10 โฒ. the frame 1 has a base plate 13 , a supporting arm 14 and a pedal axle 12 . the supporting arm 14 extends upward from the base plate 13 . the supporting arm 14 has a distal end which splits into two rack poles 141 , 142 . each rack pole 141 , 142 is formed with an axial hole 11 , 11 โฒ. each axial hole 11 , 11 โฒ extends horizontally . the two axial holes 11 , 11 โฒ of the supporting arm 14 are coaxial . the pedal axle 12 is disposed on the base plate 13 . the pedal axle 12 extends horizontally . the two axial holes 11 , 11 โฒ and the pedal axle are non - coaxial . the frame 1 โฒ has a similar structure to the frame 1 . the first main axle 2 is rotatably received in two axial holes 11 , 11 โฒ of the supporting arm 14 . the second main axle 2 โฒ is rotatably disposed on the other flame 1 โฒ. each main axle 2 , 2 โฒ is rotatable about its longitudinal direction . the first main axle has an inner surface . a penetrating hole is defined in the inner surface so that the first main axle is a tube - shaped axle . please refer to fig3 a . the penetrating hole has a first end 21 , a second end 22 , a first section 23 , a second section 24 and a third section 25 . each section 23 , 24 , and 25 of the penetrating hole has an inner diameter . the inner diameter of the second section 24 is smaller than those of the other sections . the first main axle 2 forms a first abutting surface 26 between the first section 23 and the second section 24 . the first main axle 2 forms a second abutting surface 27 between the second section 24 and the third section 25 . the second main axle 2 โฒ can be a solid axle or a hollow axle , which is similar to the first main axle 2 . the first linking element 3 is disposed on the first main axle 2 in a rotational operative relationship . the second linking element 3 โฒ is disposed on the second main axle 2 โฒ in a rotational operative relationship . each linking element is adapted for a hammer to install thereon . more particularly , each linking element 3 , 3 โฒ may include a chunk , which is adapted for a hammer . or , the first linking element 3 may include a sprocket 31 and a chunk 32 , as shown in fig5 . the first main axle 2 and both the sprocket 31 and the chunk 32 are in a rotational operative relationship . each pedal 4 , 4 โฒ is pivotably disposed about one of the pedal axle 12 , 12 โฒ. thus , the pedals 4 , 4 โฒ can pivot with respect to the frames 1 , 1 โฒ. each transmission element 5 , 5 โฒ may be a linking bar . each transmission element 5 , 5 โฒ rotatably connects one of the pedals 4 , 4 โฒ to one of the linking elements 3 , 3 โฒ. the linking elements 3 , 3 โฒ rotate during the movement of the transmission elements . the transmission elements 5 , 5 โฒ move during the sway of the pedals 4 , 4 โฒ. please refer to fig5 . the transmission element 5 may also be a belt or a chain when the first linking element 3 includes the sprocket 31 . the sprocket 31 is adapted for the belt or the chain to coil thereon . the first resilient means 6 is adapted for driving a pedal 4 to return to an initial position . the second resilient means 6 โฒ, similar to the first resilient means 6 , is adapted for driving the other pedal 4 โฒ to return to another initial position . more specifically , the first resilient means includes a fixing piece 61 , a swaying piece 62 and a spring element 63 . the fixing piece 61 may be fixed on the base plate 13 or the supporting arm 14 , so that the fixing piece 61 is firmly disposed on the frame 1 . the swaying piece 62 is removably disposed on the first main axle 2 in a rotational operative relationship . the spring element 63 connects the swaying piece 62 to the fixing piece 61 . the spring element 63 provides a resilient force to rotate the swaying piece 62 , so that the first main axle 2 and the first linking part 3 rotate together . thus , the pedal 4 moves to an initial position . the second resilient means 6 โฒ is provided with a similar structure to the first resilient means 6 . for example , the second resilient means 6 โฒ may include a fixing piece 61 โฒ, a swaying piece 62 โฒ and a spring element 63 โฒ. the fixing piece 61 โฒ is firmly disposed on the frame 1 โฒ. the swaying piece 62 โฒ is removably disposed on the second main axle 2 โฒ in a rotational operative relationship . the spring element 63 โฒ connects the swaying piece 62 โฒ to the fixing piece 61 โฒ. the spring element 63 โฒ provides another resilient force to rotate the swaying piece 62 โฒ, so that the second main axle 2 โฒ and the second linking part 3 โฒ rotate together . thus , the pedal 4 โฒ moves to another initial position . the fixing piece 61 of the first resilient means 6 may further include a main fixing lump 611 and a secondary fixing lump 612 , as shown in fig6 . both the main fixing lump 611 and the secondary fixing lump 612 are adapted for a spring element to connect thereon . the secondary axle is removably disposed on the first main axle 2 . the secondary axle includes a shaft 71 . the shaft 71 is rotatable with respect to the first main axle 2 . more specifically , the secondary axle may include the shaft 71 , a first bearing 72 , a second bearing 72 โฒ and a threaded element 73 . the shaft 71 has a working portion 711 and a constructing portion 712 . one end of the working portion 711 forms a stepped surface 7111 . the constructing portion 712 extends axially from the stepped surface 7111 . the constructing portion 712 may includes a bigger diameter section 7121 and a smaller diameter section 7122 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . a distal end of the constructing portion 712 is formed with a threaded hole . the shaft 71 has a third abutting surface 713 located between the bigger diameter section 7121 and the smaller diameter section 7122 . the first bearing 72 includes an outer ring 721 and an inner ring 722 , which is received in the outer ring 721 . several balls may be disposed between the outer ring 721 and the inner ring 722 . or , the outer ring 721 may slidably contact to the inner ring 722 . thus , the outer ring 721 is rotatable with respect to the inner ring 722 . the second bearing 72 โฒ has a similar structure to the first bearing 72 . the second bearing 72 โฒ includes an outer ring 721 โฒ and an inner ring 722 โฒ, which is received in the outer ring 721 โฒ. the outer ring 721 โฒ of the second bearing 72 โฒ is rotatable with respect to the inner ring 722 โฒ of the second bearing 72 โฒ. the constructing portion 712 is received in the penetrating hole from the first end 21 . the first bearing 72 is radially disposed between the constructing portion 712 and the first main axle 2 . the first bearing 72 is axially disposed between the third abutting surface 713 and the first abutting surface 26 . the threaded element 73 mates with the threaded hole of the constructing portion 712 from the second end 22 . the second bearing 72 โฒ is axially disposed between the second abutting surface 27 and the threaded element 73 . thus , the two bearing 72 , 72 โฒ is disposed between the shaft 71 and the first main axle 2 . in other embodiment of the present invention , the shaft 71 may slidably contact to the first main axle 2 directly . the clamping element 8 is disposed on the shaft 71 in a rotational operative relationship . the clamping element 8 is adapted for a hammer to install thereon . wherein , the clamping element 8 may be disposed on the working portion 711 . the linkage member 9 removably connects the second main axle 2 โฒ to the shaft 71 in a rotational operative relationship . thus , the second main axle 2 โฒ and the shaft 71 can rotate simultaneously . one of the two hammers 10 is removably disposed on the first linking element 3 , so the hammer 10 and the linking element 3 can rotate together . the other hammer 10 โฒ is removably disposed on the clamping element 8 . in other possible embodiments of the present invention , the hammer 10 may be firmly disposed on the first linking element 3 . accordingly , the single - arm pedal assembly can be used to percuss a drum , in which the two pedals 4 , 4 โฒ can drive the two hammers respectively . when users need only one pedal and one hammer , the secondary axle and the linkage member can be removed . also , the hammer 10 โฒ may be repositioned on the second linking element 3 โฒ. in the event , the single - arm pedal assembly is reconstituted into two single - hammer pedal assemblies . each single - hammer pedal assembly has only one pedal and one hammer , as shown in fig7 . please refer to fig8 and fig9 . in another embodiment of the present invention , the shaft may include a rod 714 and a sleeve 715 . the rod 714 has two ends . one end of the rod 714 is received in the sleeve 715 . the rod 714 is rotatable with respect to the sleeve 715 . the other end of the rod 714 extends axially forming the constructing portion 712 . the working portion , which is disposed the clamping element 8 thereon , is formed with the sleeve 715 . the rod 714 may connect slidably to the sleeve 715 . or , several bearings 716 , 716 โฒ may be disposed between the rod 714 and the sleeve 715 so that the rod 714 is rotatable with respect to the sleeve 715 . please refer to fig1 to fig1 . in another embodiment of the present invention , the constructing portion 712 may include a bigger diameter section 7121 , a smaller diameter section 7122 , a screw section 7123 and a stretching section 7124 . the bigger diameter section 7121 connects the smaller diameter section 7122 to the working portion 711 . the screw section 7123 connects the stretching section 7124 to the smaller diameter section 7122 . the smaller diameter section 7122 is received in the second bearing 72 . the threaded element 73 mates with the screw section 7123 . the stretching section 7124 passes through the second end 22 of the penetrating hole . as a result , the swaying piece 62 โฒ of the second resilient means may be repositioned on the stretching section 7124 . the spring element 63 โฒ of the second resilient means can connect the swaying piece of the second resilient means to the secondary lump of the fixing piece 61 of the first resilient means . the spring element 63 โฒ of the second resilient means can make the swaying piece 62 โฒ of the second resilient means and the shaft 71 rotate . | Does the content of this patent fall under the category of 'Physics'? | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | 0.25 | 2577315ceddb3ed722aaed4de79df876447d1f49b25b02b9694aa7c760cffa7d | 0.241211 | 0.087402 | 0.149414 | 0.081543 | 0.207031 | 0.111328 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Is this patent appropriately categorized as 'Human Necessities'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.203125 | 0.020996 | 0.125 | 0.000278 | 0.099609 | 0.015442 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.233398 | 0.055908 | 0.267578 | 0.03064 | 0.167969 | 0.150391 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Does the content of this patent fall under the category of 'Chemistry; Metallurgy'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.203125 | 0.086426 | 0.125 | 0.006683 | 0.099609 | 0.024414 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Should this patent be classified under 'Textiles; Paper'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.203125 | 0.000116 | 0.125 | 0.000008 | 0.099609 | 0.000345 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | Is 'Fixed Constructions' the correct technical category for the patent? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.233398 | 0.031128 | 0.267578 | 0.01001 | 0.167969 | 0.053467 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.128906 | 0.077148 | 0.193359 | 0.00885 | 0.114258 | 0.095215 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Is 'General tagging of new or cross-sectional technology' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Physics'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.128906 | 0.054932 | 0.193359 | 0.004913 | 0.114258 | 0.069336 |
null | the machine which is designated generally by reference numeral 10 , comprises a machine cabinet employing a suitable vertical and horizontal framework covered by a metal housing comprising a top 12 , front 14 , sides 15 , back 16 and work table 18 , supported on a bottom machine base 20 . the work table , or saw platform , 18 is supported on the machine framework to provide a horizontal support surface on which is supported a plastic material 22 , such as a block or sheet of acrylic plastic , to be cut . a stationary wire guide assembly 26 located below the work table 18 employs a wire guide means . an adjustable wire guide assembly 28 is located on the machine 10 frame above the work table 18 . the resistance wire cutting element designated generally by reference numeral 30 is guided between the fixed or stationary wire guide assembly 26 and the adjustable wire guide assembly 28 to provide a reciprocating wire 30 above and through a hole in the work table 18 , for the purpose of cutting plastic ( or wood ) material 22 placed thereon and manipulated by hand . wire 30 may be nichrome wire such as a driver - harris no . v , or equal , capable of withstanding incandescent temperatures required for vaporizing materials rather than melting same . wire 30 is reciprocated and caused to retrace its path in such a manner that positive electrical contact is maintained and the wire is not bent or worked in the process . the guide means , the fixed guide 26 and adjustable guide 28 each have two pivotally connected bearing sections 31 , 31 &# 39 ; having bearing surfaces molded from a material comprised of gypsum plaster ( hydrated calcium sulfate ) and &# 34 ; teflon &# 34 ; ( tm ): ( trademark for tetra fluoro ethylene ) particles . adjustable guide 28 has pivoted jaws 32 each holding a bearing 31 , 31 &# 39 ; on a base plate 33 . both guides 26 , 28 have adjustable springs 34 and adjustment nuts 35 . the bearing sections 31 , 31 &# 39 ; are shaped so that they may be held in a frame so as to provide a tongue and groove conformation . the cutting wire 30 rides between sections 31 , 31 &# 39 ; in such a manner that the opposing springs 34 exert a slight pressure on the cutting wire to hold it in a true path . wire 30 is reciprocated by means of a nonconducting drive cable 36 having the strand of nichrome 5 wire 30 attached thereto by a thermal clip 38 attached at one end and by means of another clip assembly 40 at the other end . which passes around a series of idler pulleys 44 , 46 , 48 , 50 , 52 , 54 , 56 and 58 located on respective shafts at different locations on the frame of the machine . it will be noted that the path of this nonconducting drive cable 36 forms an open throat between pulleys 58 and 52 . the work table 18 is mounted on the machine frame parallel to base 20 , at the lower extremity of this throat . the strand of nichrome 5 cutting wire passes through a 1 / 2 inch round hole in the work table 18 . one end of wire 30 is attached by means of the terminal clip assembly 38 , to the nonconducting drive cable 36 at a point just above pulley 58 by hooking a knotted end of wire 30 in a clip 59 . clip assembly 40 is attached to one end of a take - up spring 42 . the other end of this spring 42 is connected to the nonconducting drive cable 36 at a point below pulley 52 . in this way the nichrome 5 cutting wire 30 is suspended in such a manner that it closes the throat formed by the path of the nonconducting drive cable between pulleys 58 and 52 . the motor 62 has a drive pulley 64 driving a belt 66 which drives a double grooved pulley 68 . a belt 70 riding in the second groove of pulley 68 drives idler pulley 72 . a swivel device 74 is attached to belt 70 and firmly connected to nonconducting drive cable 36 . when the motor 62 is operated , belt 70 revolves around pulley 68 and 72 in an elliptical pattern . this action causes the nonconducting drive cable 36 to first move upward for the travel distance between the outer circumferences of pulleys 68 and 72 , then to reverse itself and move downward the same distance and again reverse its movement . this reversing action is translated to the cutting wire 30 by the nonconducting drive cable to provide a reciprocating motion . electrical current for providing electrical resistance heating is supplied through a transformer 80 to the cutting wire through flexible leads 82 and 84 , which are firmly attached to the thermal clip assemblies 38 and 40 , respectively . also included in the electrical circuit with transformer 80 are a control panel 86 which includes a rheostat r and switches sr for adjusting the voltage and resistance in the nichrome wire circuit . the control panel 86 also includes a separate switch sw2 for the drive motor and another switch sw3 for the motor of an exhaust fan 90 . except for the throat of the &# 34 ; c &# 34 ; where the worktable 18 is provided , the entire machine is mounted in a cabinet completely enclosed and made as airtight as possible , except for vent holes 14a and 14b in the front panel of the cabinet in the area where the nichrome wire 30 travels . the exhaust blower 90 is mounted in the cabinet to serve two purposes : one is to remove the fumes which occur directly above the work table when the materials being cut are vaporized in the cutting process . this is accomplished by means of an exhaust vent 93 immediately above the work table 18 . the other purpose is to provide air movement for quenching or cooling those sections of the cutting wire 30 not in contact or not imminently to be in contact with the material being severed . this air quenching action has been found to be basically worthwhile to the efficient performance of this machine . experimentation in cutting a wide variety of materials has shown that the best results , such as fast cutting and smooth , polished appearing cut surfaces are only achieved when the cutting wire glows brightly and reaches a temperature in the range of 1500 ยฐ f to 1700 ยฐ f . maintaining this temperature in the cutting wire 30 where it is in contact with the material being severed 22 , without air quenching , those portions of the cutting wire 30 , not in contact with the work , could result in overheating the wire above 91 and below 92 the work area , so that the wire would soon disintegrate , depending upon the particular wire . when the material being cut 22 , comes in contact with the cutting wire 30 , the material acts as a heat sink , cooling the wire . this means that these sections of the wire 91 and 92 not being cooled by contact with the material would overheat . when a heavy cutting wire is employed , lower voltage or higher resistance is required to reach the optimum temperature for satisfactory cutting action . this may be achieved by means of the rheostat and switches on the control panel 86 but to compensate for the larger cross section or greater mass of the larger wire , it is desirable to provide more air movement around the wire in areas 91 and 92 . this adjustment may be made by changing the position of the louvres which pivot at points 13a and 13b to open or close air vents 14a and 14b . the wire guide 28 and a similar wire guide 26 mounted below the work table 18 provides accurate guiding of the nichrome wire 30 . the upper guide 28 is mounted in such a way that it may be raised up or down by means of a slide and set screw 96 according to the thickness of the material being severed . in the modified form shown in fig6 a machine cabinet 100 employs a machine frame 102 on which is mounted a reciprocating nichrome cutting wire 104 operating through suitable guide means 106 , 108 mounted above and below a work table 110 which is located in the throat of a cabinet shaped like a letter c . a pair of rocker assemblies 112 comprise a circular rocker member 114 , 114a and an elongated rocker shaft 116 , 116a mounted on a pivot 118 on the frame of the machine . the ends of the respective rocker arms 116 and 116a are connected by means of a rod 120 attached to respective pivots 122 , 124 and serve to oscillate the respective rocker arms 114 and 114a . in turn , rod 120 is driven by connecting rod 130 having one end attached to a pivot 132 on the rod 120 and the other end attached to a drive pulley pivot 134 on a drive wheel 136 rotating about a shaft 138 mounted on the machine . a motor 140 has a drive pulley 142 which drives the drive wheel 136 by means of a drive belt 144 . the nichrome wire 104 is attached to the respective rocker arms by means of flexible wire conductors 150 , 152 attached by tie clips 154 and a take - up spring 156 . the respective flexible conductors are electrically connected through a transformer 160 by means of electrical flexible conductors 162 , 164 and conductor 164 leads through a control panel 166 having switches 168 and a controllable rheostat 170 for controlling current to the nichrome wire 104 . referring to the third embodiment shown in fig8 - 15 inclusive , the machine 200 , which is similar to those in the previous embodiments , has a machine frame 202 comprising horizontal frame members 204 and vertical frame members 206 . a traveling c - frame 208 provides a means for moving the heated wire 210 in lieu of the apparatus provided in the previous embodiments . the frame 208 is mounted for vertical movement on a pair of vertical guide bars 212 , 214 which are in substantial alignment but separated by the work space 216 which is defined by structural members 218 to provide a structural support for a work table 220 supported on a hinged strut 222 . the traveling c frame 208 comprises an upper horizontal frame member 224 attached to a rear vertical frame member 226 which is attached to a lower horizontal frame member 228 thereby providing a rigid frame . a pair of rollers 230 on frame 208 are mounted about upper guide bar 212 and a pair of rollers 232 are mounted on frame 208 about lower guide bar 214 so that frame 208 travels freely upwardly and downwardly on guide bars 212 , 214 . the frame 208 is driven and reciprocated vertically by means of a frame drive assembly comprising a motor 233 which drives a belt 234 driving a pulley 236 which has the face thereof attached to the face of a sprocket 238 on common shaft 240 . sprocket 238 drives a drive chain 242 which drives around another sprocket 244 mounted on a shaft 246 . the drive chain 242 is attached to the c - frame by means of a pivot connector assembly comprising a pivot pin 248 attached to one link of the chain and also attached to a spring cartridge which comprises a plunger 250 and a double acting spring 252 inside a case 253 ( see fig1 and 15 ). a connector pin 254 attaches one end of the plunger 250 to a bracket 256 attached about a vertical guide bar 258 to the traveling c - frame 208 , supporting a pair of rollers 260 which travel on bar 258 . the cutting wire 210 is attached to the c - frame by means of a clip assembly 262 which is insulated from the frame 208 and the wire 210 passes through a hole in the work table 220 and is attached at the bottom end of the frame 208 by means of a similar clip assembly 264 suspended on a take - up spring 266 . flexible electrical leads 268 , 270 are attached to each clip assembly and through a transformer 272 , control panel 274 to power source such as 115 volts a . c . the wire guide means may be the spring biased , jaw arrangement with gypsum bearings , etc . as described previously . when motor 233 is energized , chain 242 is caused to travel in an elliptical path pulling pivot connector 250 to the upper perimeter of sprocket 244 and then down to the lower perimeter of sprocket 238 . this action moves c frme 208 up and down the distance between the outer perimeters of sprockets 244 , 238 which causes c frame 208 and cutting wire 210 to move up and down the same distance . wire guides 280 , one mounted on the cabinet just above the work table 220 and another under work table 220 hold the cutting wire 210 in an axially stable path . when a switch is turned on in control panel 274 , the cutting wire 210 which is nichrome v , resistance wire , is energized and heated . another switch ( not shown ) in control panel 274 energizes an exhaust blower 284 which draws air through vent holes 286 and also through venthood 288 . this suction action draws air from outside the cabinet across the cutting wire 210 both above and below the work area of the machine , serving to cool the cutting wire 210 in these areas where it is not in contact with the material 290 being cut . sliding louvres 292 , 294 may be adjusted to increase or decrease air flow as needed to maintain optimum cutting temprature in the work area without overheating the wire above and below this area . as this machine employs only a relatively short strand of nichrome 5 cutting wire , little resistance is encountered and high temperatures ( 1500 ยฐ f to 1700 ยฐ f ) can be attained in the cutting wire with low voltage and amperage . however , it is desirable to provide vent cooling louvres 292 , 294 in order to air quench those portions of the wire not in contact or not imminently to be in contact , with the material being severed . by air quenching the sections of wire inside the cabinet above and below the work area it is possible to raise the wire temperature in the work area to optimum temperature without overheating those sections not in contact with the material being severed . in this manner the optimum temperatures for cutting materials of various densities and thicknesses may be attained without damaging the cutting wire through overheating . at high wire temperatures , 1500 ยฐ f to 1700 ยฐ f , combustible materials are vaporized , rather than melted and the vapors or fumes are removed through venthood 288 . in order to hold the cutting wire in an axially stable position when material to be cut is fed into the wire , the wire guide system ( guides 106 and 108 in fig6 ; guides 280 in fig8 ; guides 28 in fig1 ) is provided so that the cutting wire does not deviate from its true path when pressure is placed against it . in the manner described in connection with fig3 et al , each guide consists of a bracket and two sections of a special material made of plaster and teflon . this material is molded so that one section forms a tongue and the other forms a groove . these are mounted in a pivoted bracket and each section is backed up by lower compression spring in such a manner that the tongue and groove oppose each other . the cutting wire is passed between this tongue and groove at a 90 ยฐ angle so that the wire moves freely up and down and soon wears a notch in the plaster material , which serves as a track to hold the cutting wire in an axially stable position . therefore , it is seen that the present invention makes it possible to use a comparatively short strand of nichrome v , or similar wire 30 et al , and to eliminate such bothersome things as changing spools of wire . also the use of welded junctions and all of the attendant problems has been eliminated . it is not necessary to provide electrical commutators or sliding electrical contacts because the present wires may be solidly connected directly to the cutting wire 30 , 104 . the use of rollers or sliding electrodes in contact with the cutting element has been eliminated and in the present device the two ends of the cutting wire are clamped in fixed position with respect to their electrical connection , and flexible electrical leads are permanently attached to the clamps . such an arrangement reduces the possibility of poor contact and arcing , and completely avoids the abrasive effects on the cutting wire which rollers or sliding contacts woud cause . since it may be necessary to replace the heated wire in any system , in the present device such changes are made quite easily , quickly and at very small cost for the wire , as compared to continuous systems in which changes in the wire are very time consuming and the wire is very costly . it is also possible to change wires and wire sizes with very little difficulty in a range as fine as 0 . 005 and as large as 0 . 025 for various cutting operations . this method for precisely fixing the vertical path in which the cutting wire travels makes it practical for this device to precisely duplicate a design by use of a pantograph . various material may be cut , including polyethylene , polystyrene , ( solid or expanded ), polyurethane ( foam , rigid or flexible ), acrylic ( methyl - methacrylite ), nylon , polyvinyl acetate , and polycarbonate , walnut , mahogany , hickory , oak and plywoods . other wires may be used than nichrome in all sizes from about 0 . 005 to 0 . 025 - fine wires requiring less amperage and making finer cuts and the heavier wires being better for thicker or denser materials . an example of approximate cutting speeds : 1 / 8 acrylic at 10 inches per minute ; 1 / 4inch basswood at 20 inches per minute ; 1 / 4 walnut at 4 inches per minute . a typical machine makes one complete cycle per second and the wire travels about 2 &# 39 ; 6 &# 34 ; in each direction which is about 5 feet per second . with the present device , the strand of cutting wire 30 may be easily detached from the clamp at one end and threaded through a small hole drilled in the material , then reattached to the clamp so that a continuous design , such as a ring , may be cut out of the material without a break in the outside border . the foregoing description does not constitute any sort of limitation on the scope of the invention since various changes and departures may be made without avoiding the invention as defined only by a proper interpretation of the appended claims . | Should this patent be classified under 'General tagging of new or cross-sectional technology'? | Is this patent appropriately categorized as 'Electricity'? | 0.25 | 1302b3db82ac6bc1d42d11971a3ff6ba8801cbca442b66e211f1f5bc17c9375f | 0.203125 | 0.271484 | 0.125 | 0.017456 | 0.099609 | 0.037842 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is this patent appropriately categorized as 'Physics'? | Is 'Human Necessities' the correct technical category for the patent? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.326172 | 0.000938 | 0.332031 | 0.000055 | 0.192383 | 0.00103 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'Performing Operations; Transporting'? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.277344 | 0.002182 | 0.158203 | 0.000357 | 0.164063 | 0.00885 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is 'Physics' the correct technical category for the patent? | Should this patent be classified under 'Chemistry; Metallurgy'? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.277344 | 0.00193 | 0.158203 | 0.000075 | 0.164063 | 0.00592 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is 'Physics' the correct technical category for the patent? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.277344 | 0.002258 | 0.158203 | 0.000055 | 0.164063 | 0.012451 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is 'Physics' the correct technical category for the patent? | Does the content of this patent fall under the category of 'Fixed Constructions'? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.279297 | 0.029297 | 0.158203 | 0.006104 | 0.164063 | 0.092773 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is this patent appropriately categorized as 'Physics'? | Is this patent appropriately categorized as 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting'? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.326172 | 0.000687 | 0.332031 | 0.000149 | 0.192383 | 0.007568 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | Is 'Physics' the correct technical category for the patent? | Is 'Electricity' the correct technical category for the patent? | 0.25 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.279297 | 0.151367 | 0.158203 | 0.016357 | 0.164063 | 0.020996 |
null | in fig1 a liquid crystal display 10 includes a liquid crystal cell 12 with means 14 positioned adjacent the cell for illuminating the cell in transmission for a viewer 16 through means 17 for diffusing the transmitted light . means 18 for applying a pattern of electrical signals to modulate the transmitted light corresponding to an image to be displayed thereon are attached to the cell 12 . in fig2 the cell 12 includes a first substrate 20 having first and second major surfaces 22 and 24 , respectively , and a second substrate 26 having first and second major surfaces 28 and 30 , respectively . a first electrode structure 32 overlies the first major surface 22 of the first substrate 20 and a first alignment layer 38 overlies the structure 32 . a second electrode structure 36 overlies the first major surface 28 of the second substrate 26 and a second alignment layer 38 overlies the structure 36 . a liquid crystal 40 fills the space between the alignment layers 34 and 38 and a sealant 42 contains the liquid crystal between the substrates 20 and 26 . means 44 for polarizing light incident on the second major surface 24 of the first substrate 20 and means 46 for analyzing the polarized light transmitted through the second substrate 26 are attached to the second major surfaces 24 and 30 , respectively . the means 44 and 46 are typically sheet polarizers . spacers typically used to maintain a uniform spacing between the substrates are not shown . in fig3 the orientation of the director between the substrates 20 and 26 varies along an optical axis 50 which is collinear with a normal 52 to the second major surface 30 . typically the directors 54 and 56 adjacent the first and second substrates 20 and 26 , respectively , are oriented at 90 ยฐ to one another with the midpoint director 58 being oriented halfway between the orientation of the directors 54 and 56 adjacent the surfaces . the principal viewing plane is defined as the plane containing the midpoint director 58 and the normal 52 . the plane of constant electro - optic response is orthogonal to the principal viewing plane and is defined as the plane containing the normal 52 and a line perpendicular to both the midpoint director 58 and the normal 52 . the illumination means 14 is positioned so that the light incident on the second major surface 24 is substantially collimated in the principal viewing plane and is substantially uncollimated in the plane of constant electro - optic response . light incident on the second major surface 24 is preferably polarized either parallel or perpendicular to the director 54 adjacent the first substrate 20 and the analyzing means 46 are preferably oriented to transmit light polarized at 0 ยฐ or 90 ยฐ to the polarization of the incident light . the substrates 20 and 26 are typically composed of a material such as glass which is substantially transparent in the visible wavelength spectrum . the electrode structures 32 and 36 are well - known in the art and are typically composed of tin oxide or indium tin oxide about 100 nanometers ( nm ) thick which are transparent in the visible wavelength spectrum and which may be deposited by evaporation , sputtering or chemical vapor deposition . these layers are patterned to form the electrodes of individual pixels . the structures 32 and 36 include any associated conductive lines necessary to address the individual pixels and may also include active elements such as diodes , transistors and capacitors used in active addressing of a pixel as disclosed , for example , by mao in u . s . pat . no . 3 , 653 , 745 and by marlowe et al . in u . s . pat . no . 3 , 654 , 606 , both of which are incorporated herein by reference . preferably these active elements are small so as to maintain a high optical transmission through the display . the first and second electrode structures 32 and 36 comprise means for modulating the transmission of the liquid crystal 40 in response to a pattern of electrical signals applied thereto . the alignment layers 34 and 38 are preferably composed of a polyimide material about 100 nm thick deposited by spin coating followed by thermal curing . this material is typically treated by rubbing with a cloth in the desired alignment direction . the liquid crystal is typically a nematic material having a positive dielectric anisotropy and containing a small amount of a cholesteric liquid crystal to insure uniform twist . preferably a material such as type no . zli - 1800 - 000 or zli - 2293 nematic material , manufactured by e . merck , inc ., darmstadt , republic of germany , is used . the liquid crystal is loaded into the cell and the director adjacent the substrate surfaces aligned using techniques well known in the art . the transmission t , through a cell with a 90 ยฐ twist angle and parallel polarizers , as disclosed , for example , by gooch et al . in electronics letters , 10 , 2 ( 1974 ) is : ## equ1 ## where x = 2dฮดn / ฮป , d is the material thickness , ฮดn is the difference in the principal refractive indices and ฮป is the wavelength . the transmission of the cell is an oscillatory function of the liquid crystal thickness . this thickness is typically chosen to correspond to a minimum in the transmission of light through the cell . in particular , i have found that a thickness corresponding to the first gooch - tarry minimum in the transmission is preferred . this preferred thickness d is 0 . 87 ฮป / ฮดn . typically the thickness is chosen to correspond to the first minimum for a wavelength between 400 and 700 nm . for illumination with a band of wavelengths the wavelength at about the center of the band is preferably used to determine the thickness . alternatively , the different elements of a pixel corresponding to the different primary colors may have different thicknesses corresponding to the first gooch - tarry minimum at the wavelength of the particular primary color . the means for illuminating the cell 12 provides a beam of light which is substantially collimated , typically having a divergence half - angle of about 30 ยฐ or less and preferably less than 15 ยฐ in one plane , and substantially uncollimated , typically having a divergence half - angle greater than about 45 ยฐ and preferably approximating a distribution , defined by lambert &# 39 ; s law in the orthogonal plane . the divergence half - angle is defined as the angle from the center of symmetry of the light beam to its half intensity point . in fig4 a suitable means 14 for illuminating the cell 12 includes a light source 62 mounted in a parabolic reflector 64 . the light source 62 is typically a line source such as a fluorescent tube . the parabolic reflector 64 is shaped such that the emitted light is substantially collimated in the plane of fig4 and substantially uncollimated in the orthogonal plane . the means 17 for diverging the substantially collimated light in the principal viewing plane is typically a cylindrical lenticular screen typically having a pitch of about 50 micrometers ( ฮผm ) and a full half - circle depth . the closer the screen is placed to the cell 12 , the less it will degrade the resolution of the display 10 . i have found that , when the incident light is substantially collimated in the principal viewing plane and substantially uncollimated in the orthogonal plane , as described with reference to fig3 the electro - optic curve is substantially constant over a wide range of viewing angles in this orthogonal plane . in fig5 the viewing angles ฮธ and ฯ for a light ray 70 are defined relative to a normal 52 and the orientation of a midpoint director 58 . preferably the collimated light beam in the principal viewing plane is substantially perpendicular to the light entry surface but may be at an angle to this surface . the effect of a non - normal incidence is to shift the electro - optic curve in voltage . the electro - optic curves were measured on a cell with a merck zli - 1800 - 000 nematic liquid crystal having a refractive index anisotropy ฮดn = 0 . 08 with a 90 ยฐ twist angle and a thickness of 6 or 13 . 5 ฮผm corresponding approximately to the first and second gooch - tarry minima , respectively , at a wavelength of 550 nm . the transmission through crossed polarizers of an incandescent light source was measured at different viewing angles using a detector having an angular resolution less than ยฑ 2 ยฐ. in fig6 the electro - optic curve in the orthogonal plane ( ฯ equal to 90 ยฐ and 270 ยฐ as defined in fig5 ) is substantially the same up to a polar angle ฮธ of about 45 ยฐ for a cell having a thickness of 6 ฮผm . at polar angles ฮธ of 60 ยฐ and 70 ยฐ the curves are displaced to slightly lower voltages . for all viewing angles the electro - optic curve is symmetrical about the principal viewing plane . in fig7 the electro - optic curve for the same cell in the principal viewing plane ( ฯ equal to 0 ยฐ and 180 ยฐ as defined in fig5 ) changes markedly with the polar angle ฮธ , exhibiting a greater variation for a 15 ยฐ change in polar angle ฮธ than a 70 ยฐ change produced in the orthogonal plane and is also assymmetrical about the orthogonal plane . in fig8 the electro - optic curve for a cell having a thickness of 13 . 5 ฮผm shows a variation with polar angle ฮธ which is significantly greater than that for a first minimum cell in the orthogonal direction but which is still much less than that observed in the principal viewing plane for a first gooch - tarry minimum cell . while the principles of the invention have been described in terms of particular embodiments , it is to be understood that the invention is not limited to the details contained therein . in particular the principles of the invention are applicable to twist angles other than 90 ยฐ and to polarizer orientations other than parallel or perpendicular to the director adjacent the light entry surface . for example , a cell having a 0 ยฐ twist with the polarizers oriented at 45 ยฐ to the director is useful . | 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 | 95eff738a0ca078887563ffce771d74113c9d3d620b85a75f289ec37acb4be1e | 0.279297 | 0.125977 | 0.158203 | 0.035156 | 0.164063 | 0.08252 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Does the content of this patent fall under the category of 'Fixed Constructions'? | Should this patent be classified under 'Human Necessities'? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.057373 | 0.007111 | 0.109863 | 0.000132 | 0.088867 | 0.003082 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Should this patent be classified under 'Fixed Constructions'? | Is 'Performing Operations; Transporting' the correct technical category for the patent? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.008606 | 0.010986 | 0.020996 | 0.030273 | 0.01001 | 0.039551 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Is this patent appropriately categorized as 'Fixed Constructions'? | Is 'Chemistry; Metallurgy' the correct technical category for the patent? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.013611 | 0.004456 | 0.031982 | 0.000336 | 0.039551 | 0.004059 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Is this patent appropriately categorized as 'Fixed Constructions'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.013611 | 0.000626 | 0.031982 | 0.000023 | 0.039551 | 0.002319 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Should this patent be classified under 'Fixed Constructions'? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.008606 | 0.012817 | 0.020996 | 0.001457 | 0.01001 | 0.030273 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Is this patent appropriately categorized as 'Fixed Constructions'? | Should this patent be classified under 'Physics'? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.013611 | 0.140625 | 0.031982 | 0.115723 | 0.039551 | 0.056641 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Should this patent be classified under 'Fixed Constructions'? | Should this patent be classified under 'Electricity'? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.008606 | 0.014038 | 0.020996 | 0.010681 | 0.01001 | 0.000278 |
null | fig1 represents a first embodiment of a suspended soffit , canopy or like static structure 10 that is exposed to up - lift wind loading . the structure or system 10 includes a rectangular grid 11 , of generally known , conventional construction . the grid 11 includes main runners 12 in the form of inverted tees and cross runners 13 shown as flanged u - shaped channels . the main runners 12 are preferably formed of sheet metal , as is conventional , and have a hollow reinforcing bulb 14 at an upper edge , a double web 16 extending from the bulb and flange portions 17 extending from opposite sides of the web . the flange portions 17 can be covered at a lower face of the main runner 12 by a sheet metal strip that forms a cap 18 with its longitudinal edges 19 folded over the longitudinal digital edges of the flange portions 17 . together the flange portions 17 and cap 18 form a flange proper 20 . typically , the overall height of the bulb 14 is 1ยฝ โณ, its width is ยผ โฒ and the flange 20 is 15 / 16 โณ or 1ยฝ โณ wide . preferably , the cross runners 13 are formed of sheet metal and have ends that overlie the main runner flange portions 17 and cap edges 19 . the cross runners 13 include tabs 21 that extend through slots in the web 16 of the main runner 12 . suitable rigid water - resistant or waterproof panel material is secured to the lower faces of the main and cross runners 12 and 13 . this panel material 23 can be sheet rock ยฎ brand exterior ceiling board , fiber rock ยฎ brand sheeting , aqua - tough โข and durock ยฎ brand cement board , such being trademarks of usg corporation . the panels 23 are attached in a conventional manner with self - drilling and tapping screws , for example . the main runners 12 are suspended from overlying structure , i . e . superstructure , by hanger wires 26 . the hanger wires 26 , made of 12 gauge steel suitably coated , are typically used in suspension ceilings , as well as soffits , and offer an inexpensive , quick and reliable way of hanging a suspended ceiling - like structure . the wires 26 , while affording adequate tensile force to support the weight of a ceiling or soffit , afford essentially no compression strength . the soffit installation 10 includes compression post assemblies 31 spaced along the lengths of the main runners 12 to hold the soffit down against wind up - lift forces that can exceed the weight of the soffit itself . the compression post assemblies 31 transfer the up - lift wind load on the soffit to the superstructure from which the soffit is hung . a compression post assembly 31 includes a main strut shaft or post 32 and a saddle fitting 33 . the main shaft 32 is preferably made of round tube stock and , in particular , can be made from thin wall electrical conduit or electrical metal tubing ( e . m . t .). in fig1 and 2 , the main shaft 32 is made of nominal ยฝ โณ e . m . t . the main post 32 , ordinarily , can be cut to length at the location where the soffit 10 is constructed . the length of the main post is slightly less than the distance between the top of the bulb 14 of the particular main runner 12 being supported from the superstructure directly above the main tee . ordinarily , the compression post assembly is installed after the grid 11 is in place so that appropriate measurements can be made to determine the suitable length of the main post 32 . fig5 - 7 , discussed below , show how a compression post assembly 31 may be located on a superstructure . the saddle fitting 33 can be made from tubing stock such as ยพ โณ e . m . t . cut to a length somewhat greater than the height of a main runner ; for instance , with a length 1ยฝ to two times the height of a main runner . the tube stock of the saddle fitting 33 is formed with diametrally opposite slots 34 extending from a lower end 36 lengthwise or axially for a distance at least equal to the height of an upper surface 37 of the main runner bulb 14 to the flange 20 of the main runner represented by the folded - over edges 19 of the cap 18 . the length of the slots 34 preferably enables the lower end 36 of the fitting 33 to rest against and bear upon the main runner flange 20 , formed by the cap edges 19 , without interfering or being obstructed by the reinforcing bulb 14 . in assembly , the saddle fitting 33 is telescoped with the main post 32 by slipping it over the main post . depending in part on the manner by which the main shaft is located on the superstructure , the saddle fitting 33 can be slipped up over the main post 32 , aligned over a bulb 14 of a main runner 12 and dropped down against the main runner flange 20 . alternatively , the saddle fitting 33 can be placed on the main runner flange 20 and the main shaft or post 32 can thereafter be telescoped into the fitting 33 . with the fitting 33 resting on and abutted against the upper flange surface 37 , the fitting can be fixed to the main runner 12 with a self - drilling , self - tapping screw fastener 38 . the main post 32 received in telescoping relation with the saddle fitting 33 abuts or can be raised to abut the overlying superstructure and in this position is fixed to the saddle fitting by a self - drilling , self - tapping screw fastener 39 which can be identical to the screw 38 holding the fitting to the main runner 12 . with the fitting 33 screwed or otherwise fixed to the tee 12 and the post or shaft 32 screwed or otherwise fixed to the fitting , these elements form a rigid structure . the compression post assembly 31 is easily used with any common superstructure . fig5 illustrates use of the compression post assembly 31 with a wood truss or joist 41 forming the superstructure . a suitable screw , e . g . a wood screw or heavy drywall screw 42 is partially driven into the joist 41 directly above a main runner 12 where the saddle fitting 33 is located or will eventually be located . fig6 illustrates an example of an installation of the compression post assembly 31 where the superstructure includes a steel bar joist 46 . the upper end of the main shaft 32 is secured to the bar joist 46 by cross - drilling the main post and affixing it to the bar joist with a wire 47 . it will be seen that the upper post end 43 is abutted against the lower face of the bar joist 46 . fig7 illustrates installation of the compression post assembly 31 with a superstructure formed of a concrete beam or slab 51 . a powder driven anchor 52 , known in the art , is driven into the concrete 51 and the upper end 43 of the main post 32 is abutted against the lower face of the concrete 51 . fig3 illustrates the lower area of a compression post assembly 56 that has a larger load bearing capacity and / or a longer strut or post length limitation than that of the compression post assembly 31 illustrated in fig1 and 2 . the compression post assembly includes a strut or post 57 which can be made from ยพ โณ e . m . t . a saddle fitting 58 can be made of a short length of 1 โณ e . m . t . that is slotted in the same manner as the earlier described fitting 33 . fig4 illustrates still another form of a compression post assembly 61 . the assembly 61 comprises a main post or shaft 62 , made for example of ยพ โณ e . m . t ., a splice segment 63 made from ยฝ โณ e . m . t . and a saddle segment or fitting 64 made of ยพ โณ e . m . t . as before , the saddle fitting or element 64 is slotted to straddle the bulb 14 and web 16 to enable the lower end of the saddle to abut the upper flange surface 37 . the splice segment 63 is telescoped within the shaft or post 62 and saddle 64 . as in the earlier embodiments , the saddle is fixed by a screw 38 to the main runner 12 and the splice segment 63 is fixed to the saddle 64 and post 62 by separate screws 39 . fig8 and 9 illustrate a saddle fitting 70 in compression post assemblies 71 and 72 . the saddle fitting 70 is a tubular member having different diameters at respective ends 73 , 74 . each end 73 , 74 is provided with slots 76 adapted to receive the bulb and web 14 , 16 of a main runner 12 . fig1 illustrates a modified form of a compression post assembly 76 . the assembly comprises a rectangular channel that forms the main shaft 77 or strut and a saddle fitting 78 . the compression post assembly 76 is analogous to the previous circular tube arrangements shown in the previously described figures . the saddle fitting 78 has a u or c - shaped configuration in a horizontal cross - section and includes a slot 79 sized to enable it to be assembled over the bulb 14 and web 16 of a main runner 12 . the fitting 78 is proportional to slide in telescoped relation to the main shaft 77 . the fitting 78 is fixed with its lower end abutting the upper side of the tee flanges by a screw 38 to the main tee 12 and the main shaft 77 by a screw 39 . as described in connection with the previous embodiments , the main shaft 77 has its upper end abutted against a downwardly facing surface of an overlying superstructure or is otherwise suitably fixed or anchored to the same in a vertical position . the compression post assembly of the invention is characterized by a sliding , preferably telescoping fit between a main post and a saddle element . the saddle element is arranged to surround the bulb and web of an inverted t - shaped main runner and to stabilize the main runner by contacting the lower flange of the main runner on both sides of the web . with the saddle fitting fixed both to the main runner and to the main shaft , the main runner is prevented from prematurely buckling by twisting about its longitudinal axis . the telescoping relation between the saddle fitting and main shaft or strut is very dimensionally tolerant of variations between the ideal length of a main post in relation to the actual distance between a main runner and its overlying superstructure . while the invention has been shown and described with respect to particular embodiments thereof , this is for the purpose of illustration rather than limitation , and other variations and modifications of the specific embodiments herein shown and described will be apparent to those skilled in the art all within the intended spirit and scope of the invention . accordingly , the patent is not to be limited in scope and effect to the specific embodiments herein shown and described nor in any other way that is inconsistent with the extent to which the progress in the art has been advanced by the invention . | Is 'Fixed Constructions' the correct technical category for the patent? | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | 0.25 | 9ae8ae1c301357eab10e67cc26d32520b18f7b3dfdc2ab36c738c0691ddab1df | 0.07373 | 0.155273 | 0.081543 | 0.298828 | 0.054932 | 0.151367 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Should this patent be classified under 'Human Necessities'? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.094238 | 0.008606 | 0.125 | 0.000035 | 0.222656 | 0.002258 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Chemistry; Metallurgy'? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.310547 | 0.002808 | 0.367188 | 0.000149 | 0.439453 | 0.000805 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Textiles; Paper'? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.176758 | 0.000854 | 0.246094 | 0.000008 | 0.429688 | 0.004059 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Is this patent appropriately categorized as 'Fixed Constructions'? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.310547 | 0.007355 | 0.367188 | 0.015869 | 0.439453 | 0.026733 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Is 'Mechanical Engineering; Lightning; Heating; Weapons; Blasting' the correct technical category for the patent? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.094238 | 0.021606 | 0.125 | 0.004333 | 0.222656 | 0.037354 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Does the content of this patent fall under the category of 'Performing Operations; Transporting'? | Is 'Physics' the correct technical category for the patent? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.318359 | 0.101074 | 0.367188 | 0.041504 | 0.439453 | 0.068359 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Is this patent appropriately categorized as 'Performing Operations; Transporting'? | Is 'Electricity' the correct technical category for the patent? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.176758 | 0.000805 | 0.246094 | 0.000828 | 0.429688 | 0.000231 |
null | fig1 shows the invention in elevation view connected to a trailer frame 10 which is shown in partial cut - away view . trailer frame 10 has a forwardly - extending tongue 12 with a ball receiver 22 at its forwardmost end . a trailer jack 14 is affixed proximate the front of tongue 12 . the jack 14 has a motor drive or crank mechanism 16 which movably positions a jack shaft 18 upwardly or downwardly . jack shaft 18 has a foot pad 20 which can be extended to contact the ground surface . trailer frame 10 has a cross - frame member 11 and a cross - frame member 13 for strengthening the frame assembly . referring to fig1 - 4 , a wheel assembly 24 is pivotally and adjustably connected to trailer frame 10 . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 by bolts or weldments . each u - bracket 26 , 28 has a pair of aligned holes through the respective brackets , the holes being sized to accept hinge pins 32 , 34 . a wishbone frame 30 has a pair of downwardly depending frame sections 36 , 38 having aligned holes through their respective ends ; hinge pins 32 , 34 respectively pivotally connect frame sections 36 , 38 to brackets 26 , 28 . these connections permit wheel assembly 24 to pivot about the axis of alignment of hinge pins 32 and 34 . the front end of wishbone frame 30 is formed into a downwardly directed frame section 40 having a plurality of aligned holes 42 at spaced apart intervals along its length . the lower end of frame section 40 has a forwardly projecting tab 44 which will be hereinafter described . a vertical cylinder 50 is affixed to wishbone frame 30 proximate its center and cylinder 50 has a pair of aligned slots 52 passing therethrough . a linch pin 54 is sized to insert through the slots 52 . a front bracket 46 is affixed to cross frame member 13 by bolts or weldment . front bracket 46 has a pair of elongate slots 48 through its respective side walls in aligned relationship . a bolt 45 is sized to fit through elongate slots 48 and also to fit through holes 42 in frame section 40 . a compression spring 60 is fitted over the exterior of cylinder 50 and a spindle 62 is fitted into the interior of cylinder 50 . spindle 62 has a pair of elongate slots 63 proximate its upper end and elongate slots 63 are sized to accept linch pin 54 . spindle 62 has a curved lower end 64 with an axle connection 65 proximate its lower extremity . axle connection 65 is adapted to receive an axle which passes through the wheel hubs for wheels 66 . a turning arm 56 is affixed to spindle 62 , and turning arm 56 is rotatable with spindle 62 about the vertical axis of spindle 62 . a pair of l - brackets 33 , 35 are each respectively connected to an inner end of hinge pin 32 , 34 . a pair of steering dampers 72 , 74 each have respective ends 73 , 75 connected to l - brackets 33 , 35 by means of threaded fasteners 76 , 78 . the respective other ends 83 , 85 of steering dampers 72 , 74 are connected to turning arm 56 by similar threaded fasteners , 86 , 88 . steering dampers 72 , 74 are conventional dashpot - type cylinders typically having air as the damping medium . each of the steering dampener ends 73 , 75 , 83 , 85 have a rubber grommet for receiving the respective threaded fasteners . these rubber grommets permit a certain degree of lateral movement of the steering dampers relative to the brackets to which they are connected . a small amount of lateral movement is to be expected , as the wheel assembly 24 will move upwardly and downwardly as it encounters different types of road surfaces . of course , an alternative and equivalent embodiment of this invention could utilize a single steering dampener connected as described instead of the two steering dampeners which are described with reference to the preferred embodiment . fig4 shows a top view of the apparatus in partial breakaway to illustrate the turning mechanism associated with the wheels 66 . in this example , the wheels as shown turn sharply to the left with turning arm 56 correspondingly turned to the left . steering damper 74 is compressed as a result of its connection to turning arm 56 and steering damper 72 is extended as a result of this connection to turning arm 56 . since both steering damper 72 and steering damper 74 comprise cylinders and pistons having air in the cylinders , both steering dampers will resist sudden extension or retraction and will thereby dampen or slow the turning motion of wheels 66 . this prevents any rapid oscillation or turning motions from taking place with respect to wheels 66 and controls the rate of turning under operating conditions . in operation , the trailer jack 14 is extended to permit foot pad 20 to contact the ground ; and the trailer jack is further extended to raise the ball receiver sufficiently to permit a vehicle trailer ball to be positioned beneath the ball receiver 22 . trailer jack 14 is then retracted until it disengages from contact with the ground , and the degree of loading of the trailer on the trailer hitch mechanism is assessed . ideally , the trailer tongue should be positioned so as to have approximately a 17 - inch clearance from the ground ; and the trailer frame and vehicle frame should be relatively horizontal with respect to the ground . if the trailer hitch is overloaded , the trailer frame and vehicle frame will be relatively lowered and the trailer ball receiver will be less than 17 inches above the ground . in this case , the jack 14 is again activated to raise the trailer tongue and bolt 45 is inserted through one of the plurality of openings 42 through front section 40 . to share a greater portion of the trailer load , front section 40 is raised to permit bolt 45 to pass through one of the lower holes in front section 40 . after bolt 45 has been secured in the proper position , the trailer jack is again retracted to lower the entire assembly into contact with the ground so that the relative horizontal positions of the trailer frame and vehicle can be reassessed . this process is continued until the trailer frame is relatively horizontal to the ground and the trailer ball receiver 22 is approximately 17 inches above the surface of the ground . for stowing the wheel assembly during periods of inoperation , the linch pin 54 may be inserted through slot 52 of cylinder 50 and slot 63 of spindle 62 . this will lock the spindle and wheels into a fixed raised position relative to the wishbone frame 30 . the forwardly projecting tab 44 on the front section 40 of wishbone frame 30 provides a safety mechanism in the event bolt 45 becomes disconnected or broken . in this situation , the front section 40 of wishbone frame 30 will tend to move upwardly in unconstrained fashion will tab 44 contacts the underside of cross frame member 13 . this engagement will permit no further dropping of the trailer frame front end and will protect against a catastrophic failure . the respective ends 73 , 83 of damper 72 and 75 , 85 of damper 74 will typically include a rubber grommet for facilitating the connection with the fasteners . the respective rubber grommets permit some lateral and longitudinal motion of the respective ends of the steering damper 72 , 74 in a manner which is typically associated with the connection of shock absorbers and the like . fig5 shows an alternative embodiment of the invention in elevation view and connected to a trailer frame 10 , which is shown in partial cutaway view . a wheel assembly 24 a is pivotally attached to a cross - frame member 11 at two points , as described earlier . a pair of u - brackets 26 , 28 are affixed to cross - frame member 11 as described , and each u - bracket has a pair of aligned holes through the respective brackets which are sized to accept hinge pins 32 , 34 . the front portion of wheel assembly 24 a has a downwardly - directed frame section 40 having a plurality of aligned holes 42 , wherein each of the holes 42 may be selectively aligned with a slot in front bracket 46 . a vertical cylinder 50 a is affixed to the wishbone frame 30 , and a piston 51 is slidably movable within the inside of cylinder 50 a . piston 51 has at least a closed top surface , and cylinder 50 a has an open bottom end for permitting piston 51 to be accepted into cylinder 50 a . an air bag 55 is placed in the space between the top surface of piston 51 and the undersurface of the top wall of cylinder 50 a . an air valve 57 is attached to air bag 55 and projects through the top wall of cylinder 50 a via sealable grommet 53 . the air pressure into air bag 55 may , therefore , be selectively controlled by adding or removing air from the air bag via air valve 57 . in operation , the compressible air bag serves as a resilient suspension means for controlling the loading effects on the wheel assembly 24 a . the air bag is also able to absorb the shock of relative movement between 50 and 51 and cylinder 50 a , as might be caused by operating the vehicle over a road surface . in all other respects , the apparatus disclosed in fig5 is similar to the apparatus previously disclosed herein . of course , other alternative embodiments may be devised to provide a similar operation to that described herein . for example , a torsion bar suspension assembly might be adapted to serve the functions described herein , or a combination of air and hydraulics might be used in connection with a piston / cylinder operation to achieve the same purpose . the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof ; and it is , therefore , desired that the present embodiment be considered in all respects as illustrative and not restrictive , reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention . | Is 'Performing Operations; Transporting' the correct technical category for the patent? | Is this patent appropriately categorized as 'General tagging of new or cross-sectional technology'? | 0.25 | b91183d88aca29ab9e5c4f66f604623b40a1124598247035f6155dabffc5343b | 0.091309 | 0.157227 | 0.125 | 0.248047 | 0.222656 | 0.161133 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.