Patent ID: 6851350

Claim:
A valve device for pressurizing or venting the piston chamber of a control cylinder, comprising at least one solenoid-actuated multi-way pressurizing valve, said at least one pressurizing valve having a first port in communication with a supply pressure and a second port in communication with a piston chamber of a control cylinder, at least one solenoid-actuated multi-way venting valve, said at least one venting valve having a first port in communication with a vent and a second port in communication with said control cylinder piston chamber, both said at least one pressurizing valve and said at least one venting valve being in closed position when deenergized, at least one non-return valve, said at least one non-return valve having a pneumatic inlet in communication with said control cylinder piston chamber, said at least one non-return valve constructed and arranged to (i) assume an unactuated position when said pneumatic inlet is depressurized, and an actuated position when said pneumatic inlet is pressurized, and (ii) permit a defined pressure leak in said unactuated position.