Abstract: The invention relates to a shuttle piston cylinder whose axially moving piston carries a power transmission element projecting out through a longitudinal slot in the wall of the cylinder barrel. A flexible seal band looped through the power transmission element seals off the slot in the parts thereof between the ends of the cylinder and the piston. The seal band is made in one piece and has a sealing lip that causes a sealing effect when acted upon by internal pressure. Furthermore the seal band has beads that are able to lock into the longitudinal slot of the barrel and hold the band therein and furthermore act to keep out dirt from the cylinder. Preferably the flexible band is reinforced by a steel band that is partly embedded in the seal band or is bonded by vulcanization onto the inner face thereof.

Abstract: The invention relates to a pressure regulating valve for pneumatic and hydraulic pressure media wherein a higher primary pressure is regulated to a desired lower secondary pressure. The valve comprises a primary connection, a secondary connection and a relief connection, there being a switch valve between the primary connection and the secondary connection, a relief valve between the secondary connection and the relief connection, and a control connection for controlling the operation of the valve in response to an external controlled quantity. The controlled quantity may be the secondary pressure output of the valve, or may be another pressure or a mechanical displacement of a larger system.

Abstract: A safety valve assembly includes a pair of parallel-connected directional control valves controlled by solenoid-operated preliminary control valves; each directional control valve has a working piston and a valve member movable in a separate bore; the bores are interconnected by crossing passages and each passage is branched into a preliminary control channel communicating via a valve seat of the preliminary control valve with the working piston to admit sufficient amount of pressure medium against the working piston to switch the same over when the preliminary control valves are simultaneously operated.

Abstract: A safety valve assembly for pressurized medium-operated devices has a housing with a supply inlet, a consumer outlet, and a return outlet, two valves operating in parallel with one another, and each having a working piston and a valve member guided in chambers of the housing and operative for establishing and interrupting the communication between the inlet and outlets via two cross-passages wherein a pressure sensing element is provided having two opposite sides each communicating with a respective one of the cross-passages and displaceable in the event of malfunctions from its inoperative to its operative position so as to act in the latter position upon an actuating member arranged to turn off a consumer in response to the displacement of the pressure sensing element to its operative position.

Abstract: A safety valve assembly for pressurized medium-operated devices has two valves operating in parallel with one another and each having a working piston and a valve member. The assembly has a housing provided with a supply inlet, a consumer outlet and a discharge outlet. The valve members of the valves are guided in chambers provided in the housing and communicating with one another by passages which crosswise connect the chambers. The valve members in the chambers establish or interrupt communication between the inlet and outlets. When a malfunction occurs, at least one valve member blocks the cross passages so that the consumer outlet does not communicate with the inlet but, instead, is vented through the discharge outlet so that no residual pressure develops in the consumer outlet.

Abstract: The coupling and brake of a press receive pressurized fluid through a safety valve. The safety valve comprises two switching valves, so that if one of the switching valves fails and cannot close the other one can be closed. The safety valve is provided with a pressure-responsive switch which generates a shut-off signal commanding that the press be shut off, in response to a variety of malfunction situations, e.g., when the switching valves are closed but nevertheless a pressure build-up is occurring, or when the switching valves are open but the pressure being furnished to the coupling and brake does not reach or suddenly drops below the threshold levels to which the coupling and brake can respond.

Abstract: A multiway switching valve includes a valve member which is mounted in an internal compartment of a housing member for displacement between two terminal positions. The valve member is retained in each of the terminal positions by a respective magnet, especially a permanent magnet of an annular configuration which bounds a passage in which a magnetically attractable portion of the valve member is received in the respective terminal position. The housing and valve members are provided with abutments which abut one another in each of the terminal positions, the abutments being so located that the magnetically attractable portions of the valve member are out of contact with the housing member even in the terminal positions of the housing member. The magnetically attractable portions of the valve member are so dimensioned as to be spaced from the annular magnets even when the valve member assumes the terminal positions thereof.

Abstract: A sliding-spool direction control valve wherein the valve body has a central space for a center land which is rigid with the shank of the valve spool. The outer lands of the spool have axially extending recesses for the respective end portions of the shank. The center space is disposed between two seats and communicates with a pressure port flanked by two working ports which, in turn, are flanked by two return ports. The outer lands are disposed between the respective working and return ports and are connected with pistons which are movable in the valve body to thereby shift the spool so that the center land engages the one or the other seat. The movements of spool can be initiated by a single electromagnetic pilot valve or by two discrete pilot valves.