Valve unit for controlling double acting fluid operating cylinders

Claim 1

A system comprising, a fluid motor formed by a double-acting operating cylinder (101) having two pressure chambers on different sides of a piston (102), a conduit connected to each of said pressure chambers, a five-way valve unit, said unit comprising: channel means (P) containing fluid under pressure; further channel means (R, S) leading to exhaust means; a housing (109); a slide (100) having recesses therein and being disposed for sliding movement in said housing; said fluid motor and said channel means and said further channel means being operatively interconnected via said conduits and said recesses in said slide, said channel means and said further channel means opening into said housing respectively through said recesses; said housing at both ends of said slide defining pre-control chambers (123 and 124), pre-control pistons (111, 113, 115, 117: 112, 114, 116, 118) being respectively located in said pre-control chambers (123 and 124) for sliding movement within said housing, equal pressure within said chambers effecting a normally centered position of said slide within said housing; two pair of solenoid valves (154, 156; 155, 157) provided to selectively connect, when selectively energized, said precontrol chambers to one of said channel means and said further channel means, said slide moving into one of its end positions when one of said pre-control chambers is connected to said channel means and into the other of its end positions when the other of said pre-control chambers is connected to said channel means thereby selectively connecting one of said pressure chambers of said fluid motor to said channel means and the other of said pressure chambers to said further channel means, a first pair (154, 155) of said valves being energized by switches (159, 160), main fluid supply channel means (136, 143) containing fluid under pressure and being interconnected with said pre-control chambers through supply passages (129, 130), said first pair of valves being connected to said main channel means, the second pair (156, 157) of said valves being energized by end-position switches (104, 105) actuated by said first pair of valves; a storage valve (146) provided in said main channel means (136, 143) downstream of the connection between said main channel means (136, 143) and said solenoid valves, said storage valve being interconnected with said first and second pair of said valves and being shiftable into its valve opened position when One of said first pair of said solenoid valves (154, 155) is energized to open said main channel means (136, 143) and into its valve closed position when one of said second pair of said solenoid valves (156, 157) is energized to shut off said main channel means (136, 143) to thereby connect said supply passages (129, 130) downstream of said storage valve (146) leading to said pre-control chambers, and; two shifting valves (137, 138) respectively provided in said supply passages (129, 130), each of said shifting valves being spring-biased into their valve opened position to open said supply passages (129, 130), and each of said shifting valves being connected to one of said first pair of said solenoid valves (154, 155) and being shiftable by energizing said first pair of said solenoid valves (154, 155) into a valve closed position to shut off said supply passages (129, 130) and to connect one of said pre-control chambers to said further channel means.

Claim 2

A system comprising, a fluid motor formed by a double-acting operating cylinder (101) having two pressure chambers on different sides of a piston (102), a conduit connected to each of said pressure chambers, a five-way valve unit, said unit comprising: channel means (P) containing fluid under pressure; further channel means (R, S) leading to exhaust means; a housing (109); a slide (100) having recesses therein and being disposed for sliding movement in said housing; said fluid motor and said channel means and said further channel means being operatively interconnected via said conduits and said recesses in said slide, said channel means and said further channel means opening into said housing respectively through said recesses; said housing at both ends of said slide defining pre-control chambers (123 and 124), pre-control pistons (111, 113, 115, 117: 112, 114, 116, 118) being respectively located in said pre-control chambers (123 and 124) for sliding movement within said housing, equal pressure within said chambers effecting a normally centered position of said slide within said housing; two pair of solenoid valves (154, 156; 155, 157) provided to selectively connect, when selectively energized, said precontrol chambers to one of said channel means and said further channel means, said slide moving into one of its end positions when one of said pre-control chambers is connected to said channel means and into the other of its end positions when the other of said pre-control chambers is connected to said channel means thereby selectively connecting one of said pressure chambers of said fluid motor to said channel means and the other of said pressure chambers to said further channel means, a first pair (154, 155) of said valves being energized by switches (159, 160), main fluid supply channel means (136, 143) containing fluid under pressure and being interconnected with said pre-control chambers through supply passages (129, 130), said first pair of valves being connected to said main channel means, the second pair (156, 157) of said valves being energized by end-position switches (104, 105) actuated by said first pair of valves; a storage valve (146) provided in said main channel means (136, 143) downstream of the connection between said main channel means (136, 143) and said solenoid valves, said storage valve being interconnected with said first and second pair of said valves and being shiftable into its valve opened position when One of said first pair of said solenoid valves (154, 155) is energized to open said main channel means (136, 143) and into its valve closed position when one of said second pair of said solenoid valves (156, 157) is energized to shut off said main channel means (136, 143) to thereby connect said supply passages (129, 130) downstream of said storage valve (146) leading to said pre-control chambers, and; two shifting valves (137, 138) respectively provided in said supply passages (129, 130), each of said shifting valves being spring-biased into their valve opened position to open said supply passages (129, 130), and each of said shifting valves being connected to one of said first pair of said solenoid valves (154, 155) and being shiftable by energizing said first pair of said solenoid valves (154, 155) into a valve closed position to shut off said supply passages (129, 130) and to connect one of said pre-control chambers to said further channel means.