An inlet baffle chamber (40) is provided in the port cover (26) of a piston pump. The inlet baffle chamber (26) fluidly connects a compressed piston chamber to an adjacent lower pressure piston chamber while the lower pressure piston chamber is in the suction cycle and separately receiving fluid from an inlet manifold (38) of the port cover (26). Instead of de-compressing high pressure fluid directly to pump's inlet (36) as in prior art pumps, the inlet baffle chamber (40) directs fluid to the next piston that is already in the suction cycle.

A hydraulic machine includes a first member (1) having a first structure (2) for a hydraulic medium opening in a first interface surface (3) and a second member having a second structure for the hydraulic medium opening in a second interface surface is described, the first interface surface (3) being in contact with the second interface surface, wherein at least one of the members (1) is provided with a support element (6) surrounding the member (1). Such a machine should have a good efficiency. To this end the support element (6) has a strength varying in circumferential direction around the member (1) and/or in thickness direction in a middle region of the member (1).

The present disclosure relates to a sealing assembly for a hydraulic piston pump/motor. The sealing assembly comprises a cylinder block, a fluid distribution member, and a sealing member disposed between the cylinder block and the fluid distribution member. The sealing member encloses and seals a fluidic connection between the cylinder block and the fluid distribution member. The present disclosure further relates to a hydraulic piston pump/motor comprising said sealing assembly.

A hydrostatic axial piston pump of swashplate construction, which is also configured to be operated as a motor, has a stationary control plate against which a rotating cylinder drum is tensioned. During operation, a tilting tendency of the cylinder drum arises in the direction of that quadrant of the control plate which is operatively connected to the first part of the displacement stroke of the pistons. The control plate has a supporting device configured for the cylinder drum. The supporting device is arranged adjacent to an outer edge of the control plate in the first quadrant thereof. The supporting device is configured to be formed by a hydrostatically relieved additional field.

A swashplate-type axial piston machine includes a housing, a first pivot bearing received in the housing, a drive shaft rotatably mounted in respect of an axis of rotation, a cylinder drum, a control plate, a third control aperture in the plate, and a first channel arranged in the housing. The first pivot bearing delimits a first and second housing space from one another. The drum and the plate are arranged in the first housing space. The plate has at least a first and at least a second control aperture. The first aperture is in fluidic exchange connection with a first fluid connection on the housing. The second aperture is in fluidic exchange connection with a second fluid connection on the housing. The third aperture is arranged in the peripheral direction between a first and a second aperture. The first channel fluidically connects the third aperture to the second housing space.

A hydraulic device 1 comprises a first member 2 movable relative to a second member 5. In such a device the risk of cavitation noise and cavitation damage should be minimized. To this end said first member 2 having a pressure chamber 3 opening in a face 7 of said first member 2 which face 7 is in contact with a contact face 6 of said second member 5, said second member 5 having a low pressure area 9, wherein a throttling flow path is provided in a groove 11 connecting said pressure chamber 3 and said low pressure area 9 when pressure chamber 3 is approaching said low pressure area 9, characterized in that a throttling resistance of said groove 11 increases in a direction of the flow through said groove 11.

A hydraulic actuator includes a cylinder, a pump, an electric motor and a central block. The mechanism or the rotating parts of the pump are directly installed in an interior of the block, and the drive shaft of the pump is correspondingly mounted in walls or in covers of the block.

An axial piston pump has a rotor rotatable around an axis relative to a swashplate; one or more pistons movable within one or more respective sleeves; a fluid inlet port for the inflow of low pressure fluid, and a fluid outlet port for the outflow of high pressure fluid; and a floating element axially positioned between, on the one side, the inlet and outlet ports and, on the other side, a sealing surface of the rotor. Surfaces of the floating element defining an inlet chamber and the outlet chamber are configured such that, in use, the low pressure fluid and the high pressure fluid act on the defining surfaces to produce a net axial force which the axially slidable floating element applies to the rotor to seal the floating element to the sealing surface of the rotor.

A hydraulic machine is provided comprising a cylinder unit (3) having a plurality of cylinders (4a, 4b) which are located on a circle line around an axis of rotation of said cylinder unit (3), a valve plate (6) located at an axial end of said cylinder unit (3) and having a through-going opening (8) for each cylinder (4a, 4b), and a port plate, said valve plate (6) and said port plate resting against each other in sliding contact at a contact face, wherein a pressure in each cylinder (4a, 4b) acts on a pressure area on a side of said valve plate (6) opposite said port plate. In such a hydraulic machine the risk of leaking should be kept small. To this end said pressure area (17) deviates from a circular form.

A hydraulic pump/motor includes: a cylinder block rotating about a rotation axis; a piston in a cylinder bore; and a valve plate facing a cylinder port. The valve plate includes: a high pressure port through which oil discharged from the cylinder port flows; a low pressure port through which the oil to be sucked into the cylinder port flows; a region disposed between the high and low pressure ports in a circumferential direction of the rotation axis and including a top dead center position facing the cylinder port of the cylinder bore in which the piston moved to a top dead center is disposed; and a residual pressure release port between the top dead center position and the low pressure port in the region. The residual pressure release port includes first and second ports disposed at positions different from each other in the radial direction of the rotation axis.