A piston accumulator, having an accumulator housing and a separating piston (8) guided for longitudinal motion therein, wherein said separating piston separates a liquid side (4) from a gas side (10) in the accumulator housing, and wherein liquid unintentionally transitions from the liquid side (4) to the gas side (10) despite a piston seal on the separating piston (8), is characterized in that, by means of a return device (28) the transitioned liquid is at least partially returned from the gas side (10) of the accumulator housing to the liquid side (4) of the latter.

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 pressure reducing valve may include a valve body, a connecting tube, and a pressure-reducing member. The valve body is a three-way intercommunicated valve body which respectively forms into a water inlet end, a water outlet end, and a pressure-reducing tube. The connecting tube is connected to an extending section thereof, and at least a first annular groove is formed at an outer periphery of the extending section for disposing an O-ring thereon. An annular surface formed between the connecting tube and the extending section is faced to the extending section. The pressure-reducing member is hollow and has a closed end and an open end, and a buffer block is installed therein. The open end is abutted against the annular surface of the extending section, and a coupled portion between the open end and the annular surface is welded together to form a welding portion therebetween.

A pressure reducing valve may include a valve body, a connecting tube, and a pressure-reducing member. The valve body is a three-way intercommunicated valve body which respectively forms into a water inlet end, a water outlet end, and a pressure-reducing tube. The connecting tube is connected to an extending section thereof, and at least a first annular groove is formed at an outer periphery of the extending section for disposing an O-ring thereon. An annular surface formed between the connecting tube and the extending section is faced to the extending section. The pressure-reducing member is hollow and has a closed end and an open end, and a buffer block is installed therein. The open end is abutted against the annular surface of the extending section, and a coupled portion between the open end and the annular surface is welded together to form a welding portion therebetween.

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 method of hydraulic actuation that includes positioning a piston within the chamber of a cylinder body, the chamber including a gas region and a fluidized region, the sidewall of the piston including at least one sealing surface for engaging the sidewall of chamber; and traversing the piston between a portion of the gas region and a portion of the fluidized region, wherein a distance of travel within the chamber that the piston traverses between the gas region and the fluidized region is less than a length of the sidewall of the piston. By increasing the length of the piston sidewall and decreasing the distance of travel for the piston, the method eliminates or substantially reduces fluid carry over in accumulators.

An accumulator piston configured to be situated within an accumulator bore of a housing for use in vehicle transmissions. The accumulator piston including a casing, the casing including a top surface, a bottom surface opposite the top surface, and a side wall situated between the top surface and the bottom surface, a pin guide protruding from the top surface of the casing, the pin guide including a centrally disposed aperture, the aperture configured to receive an elongated pin, and a sealing member encircling the side wall of the casing such that the sealing member covers any exposed surface of the side wall.

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 monitoring system includes a hydraulic accumulator including a piston movably disposed therein. At least one seal encompasses the piston. A first pressure sensor is configured to monitor pressure of a first fluid in a first chamber. A second pressure sensor is configured to monitor pressure of a second fluid in a second chamber. A first temperature sensor is disposed in the first chamber and configured to monitor the temperature of the first fluid. A second temperature sensor is disposed in the second chamber and configured to monitor the temperature of the second fluid. An electronic control unit is in communication with the sensors and programmed to in response to receiving pressure signals from the pressure sensors and temperature signals from the temperature sensors, determine a wear volume of the at least one seal; and compare the wear volume of the at least one seal to a predetermined threshold wear volume of the at least one seal to determine the remaining useful life of the hydraulic accumulator.

A seal structure is provided which enables a reduction in the number of components and an improvement of the stability in sliding of the seal portion or the backup ring portion. A sealing structure seals two members which move relative to each other, in which a seal portion or a backup ring portion placed between the two members and a bearing portion similarly placed between the two members are formed into an integral structure. The seal portion or the backup ring portion is integrally provided to one end portion in the axial direction or both end portions in the axial direction of the bearing portion having a cylindrical shape. The seal structure is used as a piston seal or a rod seal in hydraulic and pneumatic devices in which a piston is inserted into a shell or a cylinder tube.