A brake system damping device includes a first chamber on which hydraulic pressure is to be applied, a second chamber with a compressible medium located therein, and a first separating element configured to separate the first and second chambers. The damping device further includes a third chamber with a compressible medium located therein and a second separating element configured to separate the second and third chambers. The second and third chambers are connected in a medium-conducting manner via a passage in the second separating element. The first separating element is configured to move a closure element to close the passage when the hydraulic pressure in the first chamber has reached a predefined pressure value. The first and second separating elements form an assembly in which the first and second separating elements extend along an axis and the first separating element is covered radially on the outside by an envelope surface.

An accumulator includes a housing, a flexible bladder and a support. The housing includes a chamber having a defined volume and a passage extending through the housing. The flexible bladder is positioned within the chamber and contains a compressible gas. The bladder being operable in an expanded condition and a partially collapsed condition. The support is positioned in the chamber and engages the flexible bladder when the flexible bladder is in the expanded condition. Liquid is positioned in the chamber and in contact with the flexible bladder. A volume of the liquid within the chamber is at a minimum when the flexible bladder is in the expanded condition. The volume of liquid within the chamber increases as a pressure of the liquid increases to compress the gas and operate the flexible bladder in the partially collapsed condition.

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 bellows excellent in durability has an accordion shape where crest parts with U-shaped cross sections and trough parts with U-shaped cross sections are repeatedly formed via slope parts, the slope parts leading to the crest part includes first portions, second portions, third portions and fourth portions which are continuously connected, in order, to one another from the crest part toward the adjacent trough parts, and in a free length state of the bellows, a separation distance between the second portions of the both slope parts is longer than separation distances between the first portions and between the third portions.

A method for manufacturing a hydraulic accumulator bladder includes the following steps: bonding a rubber sheet to the gas-filled air bladder to form a bladder blank; placing the bladder blank in a vulcanization device for vulcanization to form an initial bladder product; and releasing the gas in the gas-filled air bladder of the initial bladder product, taking the air bladder out, and naturally cooling the initial bladder product to a room temperature to form a finished bladder product. The bladder manufactured by the manufacturing method is integrally formed by one-step vulcanization, and has the advantages of uniform wall thickness, smooth inner and outer surfaces, long fatigue lifetime, a simplified process, high quality and good stability.

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 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.

A hydraulic hybrid system for rotatory applications has an actuator (49, 91) in the form of a motor pump unit (91). The motor pump unit is coupled to a rotatory-operating device (94) and works as a consumer of hydraulic energy in one operating state of the device (94) and works as a producer of hydraulic energy in another operating state of the device (94). A hydraulic accumulator (1) can be charged by the motor pump unit (91) for energy storage in the one operating state and can be discharged for energy release to the motor pump unit (91) in the other operating state. The hydraulic accumulator is an adjustable hydropneumatic piston accumulator (1) in which a plurality of pressure chambers (19, 21, 23, 25) are delimited by active surfaces (11, 13, 15, 17) of different sizes on the fluid side of the accumulator piston (5). An adjusting arrangement (51) connects a selected pressure chamber (19, 21, 13, 25) or a plurality of selected pressure chambers (19, 21, 23, 25) of the piston accumulator (1) to the actuator (49, 91) depending on the prevailing pressure level on the gas side of the piston accumulator (1) and at the actuator (49, 91).

A fluid tank includes polymeric liner comprising an upper wall and a lower wall. The upper wall and the lower wall define a cavity therebetween. A weld joint joins the upper and lower walls together. A method for assembling a fluid tank includes overlapping surfaces of an upper wall and a lower wall to form a liner defining a cavity. The method includes joining the surface of the upper wall and the surface of the lower wall together by welding to form a weld joint between the upper wall and the lower wall. The method can include cooling the weld joint to control warpage of the liner at the weld joint.

The present invention provides lightweight high-pressure accumulators that avoids diaphragm failure observed in conventional diaphragm accumulators. Lightweight high-pressure composite overwrapped accumulators of the invention are made from a plurality of hollow casings that are mated to form an accumulator housing. The accumulator housing is overwrapped with a composite material to provide additional mechanical strength and structural integrity. More significantly, the accumulators of the invention includes a plurality of annular grooves and a plurality of bulb on the flexible diaphragm such that the plurality of bulbs on the flexible diaphragm are placed in the plurality of annular grooves that are formed between the first and the second hollow casing. In this manner, diaphragm failure is significantly reduced or even completely eliminated during repeated high pressure charge/discharge cycle of the accumulator.