A hydraulic block of a slip control system of a hydraulic vehicle brake system includes a hydraulic accumulator, a hollow storage cover, and an accumulator cylinder defined partly by a blind hole in the hydraulic block and partly by the hollow storage cover. The blind hole is closed by the hollow storage cover. An accumulator piston of the hydraulic accumulator is sealed and guided to or close to the ends in the blind hole in the hydraulic block and in the storage cover.

A hydraulic propulsion system converts heat or thermal energy into hydraulic energy, and such hydraulic energy into mechanical work. The hydraulic propulsion system includes a thermal unit, a hydraulic cylinder with pistons and springs mounted therein, one or more hydraulic motors, one or more hydraulic accumulators, and one or more electrical energy generators, as well as a plurality of flow control valves to control the flow of hydraulic fluid between the various components. The hydraulic propulsion system may be enhanced by a sonic transmission unit including a sonic wave generator.

An exemplary hybrid accumulator includes a piston slidably disposed in a cylinder and separating a reservoir from a pressure chamber, in use, a hydraulic fluid disposed in the reservoir and a spring disposed in the pressure chamber to act on the piston and pre-charge the hydraulic fluid to a first pressure, and a heating element in communication with the pressure chamber to increase pressure in the pressure chamber when the heating element is initiated.

A fluid pump for a linear actuator causes a rod in the actuator to extend or retract by controlling fluid flow to and from portions of a fluid chamber on either side of a piston disposed within the fluid chamber and supporting the rod. The pump includes check valves that control fluid flow between a driven pump element and each portion of the fluid chamber and a shuttle movable in response to fluid pressure along a shuttle axis extending through the valves. At least one valve includes a valve member movable between a closed position and an open position defining a fluid flow path between the driven pump element and fluid chamber and means for limiting movement of the shuttle towards the valve such that the shuttle may, depending on the position of the limiting means, move the valve member to an intermediate position between the closed and open positions.

A fluid pump for a linear actuator causes a rod in the actuator to extend or retract by controlling fluid flow to and from portions of a fluid chamber on either side of a piston disposed within the fluid chamber and supporting the rod. The pump includes check valves that control fluid flow between a driven pump element and each portion of the fluid chamber and a shuttle movable in response to fluid pressure along a shuttle axis extending through the valves. At least one valve includes a valve member movable between a closed position and an open position defining a fluid flow path between the driven pump element and fluid chamber and means for limiting movement of the shuttle towards the valve such that the shuttle may, depending on the position of the limiting means, move the valve member to an intermediate position between the closed and open positions.

A system filled with a fluid, designed for underwater applications, in which the interior of a housing and/or tank forms a fluid region which is sealed with respect to the surrounding seawater region, includes at least one hydraulic pressure compensation device, which at least raises the pressure level of the fluid region to the ambient pressure prevailing in the seawater region. The pressure compensation device is constructed in two stages in such a way that at least one store having a flexible wall region and at least one piston store having a displaceable piston are arranged in series. The use of the pressure compensation device to pressurize at least one housing filled with fluid for a hydraulic actuating shaft is also proposed.

A bootstrap hydraulic reservoir includes a bootstrap chamber to hold hydraulic fluid, a piston chamber fluidly connected to a pressure line of the hydraulic fluid system, a piston having a bootstrap end portion held within the bootstrap chamber and a pressure end portion held within the piston chamber, and a hydraulic accumulator fluidly connected to the pressure line of the hydraulic fluid system. The hydraulic accumulator accumulates pressurized hydraulic fluid from the pressure line. The bootstrap hydraulic reservoir also includes a valve fluidly connected to the pressure line of the hydraulic fluid system between the hydraulic accumulator and an outlet of a pump of the hydraulic fluid system. The valve includes an actuator selectively moves the valve to an open position when the pressure line of the hydraulic fluid system is de-pressurized.

An accumulator piston, in particular a piston for a pressure medium accumulator of a hydraulic unit of an electronically slip-controllable vehicle brake system, includes a cylindrical piston shaft, and a piston head covering the piston shaft. The piston head includes a circumferentially closed blind-hole-shaped recess having an opening. A cross section of the recess in a region of the opening has at least one smaller dimension than a cross section in a region of a base of the recess opposite the opening. The recess forms a mechanism configured to separate particles out from the pressure medium.

Disclosed is a regulator for clutch operating mechanism. The regulator includes a main body, a supply flow path for fluid flow from a master cylinder to an operating cylinder, and a return flow for fluid flow from the operating cylinder to the master cylinder inside of the main body. The regulator further includes a first valve installed inside the main body and configured to close an exit of the return flow path and open the supply flow path when the fluid flows to the operating cylinder and a second valve installed inside the main body configured to close an exit of the supply flow path and to open the return flow path when the fluid flows to the master cylinder. The regulator further includes a damping apparatus having a damping space which communicates with the supply flow path of the main body and whose internal capacity changes according to hydraulic pressure.

An apparatus including an accumulator and a drive mechanism. The accumulator includes an energy storage apparatus with a first piston face configured to reversibly compress an energy storage medium and a second piston face forming at least part of an inner surface of a corresponding second fluid chamber reversibly expandable by movement of the second piston face. A third piston face forms at least part of an inner surface of a corresponding third fluid chamber reversibly expandable by the third piston face. The first, second and third piston faces are coupled together.