The present disclosure relates to a miniature pressure compensating device (10), for balancing pressure fluctuations in a hydraulic system, comprising at least one shell (12), at least one hollow hydraulic cylinder (16), at least one reciprocating piston (26) and at least one non-return valve (NRV) (28). The hydraulic cylinder (16) comprises at least one dual charging valve port (22) for facilitating charging of both said compressible and incompressible fluid and at least one built-in two-tier sealing mechanism (24) comprising at least one metal-to-metal seal (24a) and at least one secondary seal (24b) to achieve effective isolation of the incompressible and compressible fluids. The present miniature pressure compensating device (10) has a volume below 13 cc.

An accumulator includes a pressure vessel and a partition portion separating an interior space of the pressure vessel into a liquid chamber and a gas chamber so that a volume ratio between the liquid chamber and the gas chamber in the pressure vessel is variable. The pressure vessel includes a first section including a thread portion for fastening the accumulator to a support member and a second section joined to the first section and formed by a single piece including a tool engagement portion capable of engaging with a tool for rotating the accumulator. The first section and the second section are fitted together by mating portions coaxial with the thread portion and the tool engagement portion.

A bellows accumulator, consisting of at least two housing parts (4, 6) which form an accumulator housing (2), and having a separating bellows (20), which is movably arranged in the accumulator housing (2) and separates two media spaces (8, 22) from each other and is at least on its one free end fixed to a securing device (24) in the accumulator housing (2), wherein said securing device (24) is welded to the adjacently arranged housing parts (4, 6), is characterized in that the adjacently arranged housing parts (4, 6) comprise at least in part titanium materials, in that the securing device (24) consists of at least two interconnected components (26, 30), at least one (26) of which comprises at least in part titanium materials and is welded to the adjacently arranged housing parts (4, 6), and in that the respective other component (30), consisting of a different metal material, is used for securing the separating bellows (20) to the securing device (24).

A bellows accumulator has at least one accumulator housing (2) and a separating bellows (20) movably arranged in the accumulator housing (2). The separating bellows 20 has a plurality of bellows folds and separates two media spaces (8, 22) from one another. The stationary open end of the separating bellows (20) is fixed to the accumulator housing (2) by a securing device (24). The separating bellows (20) has, at its movable other end, a closure part (36) having a guide device (40) by which the closure part (36) is guided in the accumulator housing (2). The closure part (36) has, in addition to the guide device (40), a sealing device (50). At least in the one extended end position of the separating bellows (20), the sealing device (50) separates a fluid space (8), in which the bellows folds are arranged in the accumulator housing (2), from a fluid port (12) in the accumulator housing (2). At least in some of the other working positions, the sealing device (50) releases this fluid connection.

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.

A method for producing pressure vessels, including pressure accumulators, such as hydraulic accumulators and parts of the parts of the accumulator (24). The parts produced by a 3D printing method can include one or more or all of two housing parts and a separating element separating the interior chamber of the two hosing parts are at least partially produced by a 3D printing method.

Provided is an accumulator for easier maintenance of a metal bellows. The accumulator includes a housing having a shell provided with an opening portion and a disk-shaped base body to which one end of a metal bellows with an outside diameter smaller than the inside diameter of the opening portion is welded and fixed, the interior of the housing partitioned on the inside and outside of the metal bellows in a tightly closed manner, in which the base body is formed to have an outside diameter greater than the outside diameter of the metal bellows, and the base body is fixed detachably to the shell.

A hydraulic control unit that delivers hydraulic fluid to a limited slip differential includes a hydraulic control unit housing, a motor and a pump. The hydraulic control unit housing has a manifold housing portion and an accumulator housing portion. The manifold housing portion defines a fluid pathway arrangement for communicating fluid along at least a first fluid pathway. The accumulator housing portion houses an accumulator assembly having a biasing assembly and a piston. The accumulator housing portion and manifold housing portion cooperate to form an accumulator chamber that houses the biasing assembly. The motor is disposed on the first side of the manifold housing portion. The pump is disposed on a second side of the manifold portion, opposite the first side. The pump is configured to pump fluid into the accumulator chamber of the accumulator housing portion.

A shell member 10 constituting an accumulator 100 including a cover member 30, a shell member 10 having a cylindrical portion 11, an opening portion 13 formed at one end of the cylindrical portion 11 and welded to the cover member 30, and a closed portion 12 formed at another end of the cylindrical portion 11, and an accumulation part 70 accommodated in the shell member 10. The cylindrical portion 11 includes an upper end portion 11a, and a protruding portion 11c having the opening portion 13. The protruding portion 11c is thicker than the upper end portion 11a.

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.