Programmable hydraulic drive system for transporting articles

Claim 2

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive system carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support, pump means for supplying fluid to said motor means, closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supplied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said movable support along a workpath; f. programmable circuit means for developing a predetermined pattern of prograM signals representative of the position of a preselected work station, said programmable circuit means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a pattern of signals corresponding to a preselected program, and actuatable switching means for actuating selected ones of said circuit connection means to program said control circuit, said actuatable switching means being diodes which may be removably inserted into said program board for completing selected ones of a plurality of circuit connections; g. comparator circuit means for developing a control signal having a value representative of the difference between the value of said pattern of program signals and the value of said pattern of control signals; and, h. said hydraulic circuit means coupled to said comparator means for controlling the fluid supplied to said motor means in response to said control signal developed by said comparator means to thereby energize said fluid motor means for driving said movable support from said actual position to a preselected work station.

Claim 3

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through the repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive system carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support, pump means for supplying fluid to said motor means, closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supplied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said movable support along a workpath, said position sensing means including circuit means for developing a pattern of digital signals; f. programmable circuit means for developing a predetermined pattern of program signals representative of the position of a preselected work station, said programmable circuit means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a pattern of signals corresponding to a preselected program, and actuatable switching means for actuating selected ones of said circuit connection means to program said control circuit; g. comparator circuit means for developing a control signal having a value representative of the difference between the value of said pattern of program signals and the value of said pattern of control signals; and, h. said hydraulic circuit means coupled to said comparator means for controlling the fluid supplied to said motor means in reponse to said control signal developed by said comparator means to thereby energize said fluid motor means for driving said movable support from said actual position to a preselected work station.

Claim 4

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through the repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive system carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support, pump means for supplying fluid to said motor means, closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supplied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said movable support along a workpath, said position sensing means including circuit means for developing a pattern of digital signals; f. programmable circuit means for developing a predetermined pattern of program signals representative of the position of a preselected work station, said programmable circuit means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a pattern of signals corresponding to a preselected program, and actuatable switching means for actuating selected ones of said circuit connection means to program said control circuit; g. comparator circuit means for developing a control signal having a value representative of the difference between the value of said pattern of program signals and the value of said pattern of control signals; and, h. said hydraulic circuit means coupled to said comparator means for controlling the fluid supplied to said motor means in reponse to said control signal developed by said comparator means to thereby energize said fluid motor means for driving said movable support from said actual position to a preselected work station.

Claim 5

An apparatus as defined in claim 2 wherein said control circuit includes a digital to binary coder means for converting said pattern of digital coded signals to a pattern of binary coded signals.

Claim 6

An apparatus as defined in claim 3 wherein said programmable circuit includes an output circuit means for deveLoping a pattern of binary signals having a value representative of the position of a preselected work station.

Claim 7

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive system carried on said apparatus and including a first positive displacement fluid motor; means connecting said first motor to said support for imparting movement thereto; a second positive displacement fluid motor; means connecting said second motor to said hoist means; a hydraulic drive unit for supplying fluid to said motors; said drive unit including a variable delivery pump and first and second passages connected to opposite sides of said pump; and hydraulic circuit means forming a closed loop hydraulic circuit connecting said motors in series to said first and second passages of said drive unit, said means forming said circuit including first and second three-position, four-way directional valves, said first valve having a first port connected to said first passage, second and third ports connected to opposite sides of said first motor and a fourth port connected to a first port of said second valve, said second valve having second and third ports connected to opposite sides of said second motor and a fourth port connected to said second passage, said pump including selectively positionable control means for controlling the output of fluid and thereby regulating the speed of said motors, and including a piston-cylinder means connected to control means for moving said control means to selected positions; d. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said movable support along a workpath; e. programmable circuit means for developing a predetermined pattern of program signals representative of the position of a preselected work station; f. comparator circuit means for developing a control signal having a value representative of the difference between the value of said pattern of program signals and the value of said pattern of control signals; and, g. said hydraulic circuit means coupled to said comparator means for controlling the fluid supplied to said first motor in response to said control signal developed by said comparator means to thereby energize said first fluid motor for driving said movable support from said actual position to a preselected work station.

Claim 8

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive system carried on said apparatus and including a first positive displacement fluid motor; means connecting said first motor to said support for imparting movement thereto; a second positive displacement fluid motor; means connecting said second motor to said hoist means; a hydraulic drive unit for supplying fluid to said motors; said drive unit including a variable delivery pump and first and second passages connected to opposite sides of said pump; and hydraulic circuit means forming a closed loop hydraulic circuit connecting said motors in series to said first and second passages of said drive unit, said means forming said circuit including first and second three-position, four-way directional valves, said first valve having a first port connected to said first passage, second and third ports connected to opposite sides of said first motor and a fourth port connected to a first port of said second valve, said second valve having second and third ports connected to opposite sides of said second motor and a fourth port connected to said second passage, said pump including selectively positionable control means for controlling the output of fluid and thereby regulating the speed of said motors, and including a piston-cylinder means connected to control means for moving said control means to selected positions; d. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said movable support along a workpath; e. programmable circuit means for developing a predetermined pattern of program signals representative of the position of a preselected work station; f. comparator circuit means for developing a control signal having a value representative of the difference between the value of said pattern of program signals and the value of said pattern of control signals; and, g. said hydraulic circuit means coupled to said comparator means for controlling the fluid supplied to said first motor in response to said control signal developed by said comparator means to thereby energize said first fluid motor for driving said movable support from said actual position to a preselected work station.

Claim 9

Apparatus as claimed in claim 5 wherein said drive unit includes a second pump, and fluid circuit means connecting said second pump to said piston-cylinder means, said fluid circuit means including directional valve means for controlling operation of said piston-cylinder means.

Claim 10

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support, pump means for supplying fluid to said motor means, closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supPlied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a control signal representative of the actual position of said movable support along a workpath; f. programmable means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a program signal corresponding to a preselected program, and actuatable means for actuating selected ones of said circuit connection means to program said control circuit, said actuatable means being diodes removably insertable into the program board for completing selected ones of a plurality of circuit connections; g. output circuit means for developing an output signal having a value representative of the value of said program signal and the value of said control signal; and, h. said hydraulic circuit means coupled to said output circuit means for controlling the fluid supplied to said motor means in response to said output signal developed by said output circuit means to thereby energize said fluid motor means for driving said movable support from said actual position to a preselected work station.

Claim 11

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; b. load hoist means carried by said support means; c. a hydraulic drive carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support, pump means for supplying fluid to said motor means, closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supPlied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a control signal representative of the actual position of said movable support along a workpath; f. programmable means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a program signal corresponding to a preselected program, and actuatable means for actuating selected ones of said circuit connection means to program said control circuit, said actuatable means being diodes removably insertable into the program board for completing selected ones of a plurality of circuit connections; g. output circuit means for developing an output signal having a value representative of the value of said program signal and the value of said control signal; and, h. said hydraulic circuit means coupled to said output circuit means for controlling the fluid supplied to said motor means in response to said output signal developed by said output circuit means to thereby energize said fluid motor means for driving said movable support from said actual position to a preselected work station.

Claim 12

An apparatus as defined in claim 7 wherein the position sensing means includes circuit means for developing a pattern of digital coded signals.

Claim 13

An apparatus as defined in claim 8 wherein said programmable means includes a digital-to-binary coder means for converting said pattern of digital coded signals to a pattern of binary coded signals.

Claim 14

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; load hoist means carried by said support means; c. a hydraulic drive carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support means, pump means for supplying fluid to said motor means, and closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supplied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said hoist support means along such runway; f. programmable circuit means coupled to said plurality of position sensing means for developing a predetermined pattern of program signals each representative of the position of a preselected work station; g. control circuit means coupled to said programmable circuit means for developing a plurality of control signals each having a value representative of one of said program signals, said programmable circuit means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a pattern of signals corresponding to a preselected program, and actuatable switching means for actuating selected ones of said circuit connection means to program said control circuit, said actuatable switching means being diodes which may be removably inserted into the program board for completing selected ones of a plurality of circuit connections; and, h. said hydraulic circuit means coupled to said control circuit means for controlling the supply of fluid in response to said control signals developed by said control circuit means for energizing said fluid motor means for driving said hoist support means to preselected work stations.

Claim 15

A programmable material handling apparatus for conveying work loads over a path of travel defined by a longitudinal runway to selected work stations spaced along said path of travel, said apparatus being actuatable through repeated cycles of acceleration, deacceleration and stopping during movement over said path of travel, comprising: a. hoist support means engaged on said runway for movement over said path of travel to the selected work stations; load hoist means carried by said support means; c. a hydraulic drive carried on said apparatus for actuating it through said cycles of acceleration, deacceleration, and stopping; d. said drive system including fluid motor means operatively connected to said movable support means, pump means for supplying fluid to said motor means, and closed loop hydraulic circuit means connecting said pump means to said motor means so that fluid supplied to said motor means is returned directly to said pump means; e. a plurality of position sensing means for developing a pattern of control signals representative of the actual position of said hoist support means along such runway; f. programmable circuit means coupled to said plurality of position sensing means for developing a predetermined pattern of program signals each representative of the position of a preselected work station; g. control circuit means coupled to said programmable circuit means for developing a plurality of control signals each having a value representative of one of said program signals, said programmable circuit means including a program board and a control circuit having a plurality of circuit connection means positioned on said board at positions corresponding to the positions of said work stations along said workpath, said control circuit having an output circuit means for developing a pattern of signals corresponding to a preselected program, and actuatable switching means for actuating selected ones of said circuit connection means to program said control circuit, said actuatable switching means being diodes which may be removably inserted into the program board for completing selected ones of a plurality of circuit connections; and, h. said hydraulic circuit means coupled to said control circuit means for controlling the supply of fluid in response to said control signals developed by said control circuit means for energizing said fluid motor means for driving said hoist support means to preselected work stations.

Claim 16

An apparatus as defined in claim 10 including position sensing means for developing a pattern of output signals representative of the actual position of said movable support along a workpath.

Claim 17

An apparatus as defined in claim 11 wherein said control circuit means includes comparator circuit means coupled to said position sensing means and said programmable circuit means for developing a said output signal having a value representative of the difference between the value of a said pattern of control signals and the value of a said pattern of output signals.