Abstract: In a high-pressure shut-off valve, in particular for a hydraulic pressure system having a relatively high liquid delivery rate, the pressure device of the valve body has a plurality of back support rings arranged as a stack and moveable essentially in the axial direction, i.e., in the direction of the shut-off pressure, forces the valve body onto the valve seat, such that neighboring back support rings bear against one another, causing the valve body to lift from the valve seat, whereas in the shut-off position, the neighboring back support rings inside the hydraulic system, which is under a relatively high shut-off pressure, are at a slight spacing from one another.

Abstract: In order to increase the delivery pressure of the reciprocating pump-actuating mechanism of hydraulic feed pumps having a high pumping capacity, stacks of thin spacer discs are provided on either side of a sealing ring sealingly engaged in a sealing position between the plunger and the cylindrical bushing, said stacks of spacer discs being axially movable along the plunger in the normal non-sealing position. A pressure-distributing bushing is disposed between the stack of spacer discs which faces the free end face of the plunger and the sealing ring, said pressure-distributing bushing rapidly compensating the pressure between said stack of spacer discs and the end face of the pressure-distributing bushing facing the sealing ring.