A pressure exchanger with a valve system includes a cylinder barrel (1), two valve plates (2) and two port plates (3, 4), wherein the cylinder barrel (1) has at least one cylinder (7) which accommodates a piston (8). The objective is to provide a pressure exchanger with low wear and a low maintenance effort. This objective is solved by a pressure exchanger including a piston (8) braking system and that the piston (8) includes a pressure relief arrangement.

The present invention relates to A device for supplying hydraulic power, the device comprising two hydraulic circuits jointly feeding multi-cylinder hydraulic power transmission means in which each cylinder is connected to a single one of the hydraulic circuits independently of the others. Each hydraulic circuit includes a hydraulic pressure and flow rate generator and a pressure control module controlling said hydraulic pressure and flow rate generator so as to regulate the pressure of said fluid flowing in said hydraulic circuit as a function of said pressure of said fluid flowing in each hydraulic circuit and possibly as a function of one or more parameters external to said device.

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 hydraulic 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 a positions different from each other in the radial direction of the rotation axis.

An axial piston device includes a cylinder block 11 rotatable integrally with a rotary shaft and having a plurality of cylinder chambers in a region surrounding the rotary shaft; a plurality of pistons 12 each contained in a corresponding one of the plurality of cylinder chambers; and a support configured to position respective protruding ends of the plurality of pistons; the cylinder block 11 has a plurality of cylinder ports 17 each continuous with a corresponding one of the plurality of cylinder chambers, and the plurality of cylinder ports 17 each have a central point T corresponding to the center of gravity in a cross section of a flow path at the cylinder port 17 and are, as viewed along the axis X, adjacent to one another along an imaginary circle C around the axis.

A valve plate assembly (1) of a hydraulic axial piston machine is described, the valve plate assembly comprising a wear plate (2) made of a ceramic material surrounded by a compression ring (4). Such a valve plate assembly should be produced and maintained in a cost-effective manner. To this end, the wear plate (2) is connected to a support plate (3) by means of the compression ring (4).

A valve plate assembly (1) of a hydraulic axial piston machine is described, the valve plate assembly comprising a wear plate (2) made of a ceramic material surrounded by a compression ring (4). Such a valve plate assembly should be produced and maintained in a cost-effective manner. To this end, the wear plate (2) is connected to a support plate (3) by means of the compression ring (4).

A cylinder block for a compressor includes: a shaft support configured to support a rotary shaft of an outer rotor type motor; a first support that is arranged radially outward of the shaft support and that extends along a circumferential direction about a center of the shaft support; a second support that is arranged radially outward of the first support and that extends along the circumferential direction about the center of the shaft support; a third support that connects the first support to the second support; a cylinder portion that defines a cylindrical inner space at a position radially away from the center of the shaft support; and a noise chamber defined at at least one side of the cylinder portion.

A cylinder block for a compressor includes: a shaft support configured to support a rotary shaft of an outer rotor type motor; a first support that is arranged radially outward of the shaft support and that extends along a circumferential direction about a center of the shaft support; a second support that is arranged radially outward of the first support and that extends along the circumferential direction about the center of the shaft support; a third support that connects the first support to the second support; a cylinder portion that defines a cylindrical inner space at a position radially away from the center of the shaft support; and a noise chamber defined at at least one side of the cylinder portion.

A hydraulic piston unit including a rotational group for driving or being driven by a driving shaft, and having a tiltable displacement element for adjusting the displacement volume of the rotational group between a minimum or a maximum displacement, wherein, on t valve segment between a kidney-shaped inlet port and a kidney-shaped outlet port at respective dead end positions of reciprocally moveable working pistons first and second control ports are located in fluid connection with cylinder bores in the cylinder block, for controlling the position of the displacement element. The hydraulic piston unit further includes a control valve with a shiftable control valve spool fluidly connected via a high pressure port to a high pressure side of the hydraulic piston unit. The control valve spool is configured to conduct hydraulic fluid from the high pressure side to one of the first or the second control port.

A hydraulic piston unit including a rotational group for driving or being driven by a driving shaft, and having a tiltable displacement element for adjusting the displacement volume of the rotational group between a minimum or a maximum displacement, wherein, on t valve segment between a kidney-shaped inlet port and a kidney-shaped outlet port at respective dead end positions of reciprocally moveable working pistons first and second control ports are located in fluid connection with cylinder bores in the cylinder block, for controlling the position of the displacement element. The hydraulic piston unit further includes a control valve with a shiftable control valve spool fluidly connected via a high pressure port to a high pressure side of the hydraulic piston unit. The control valve spool is configured to conduct hydraulic fluid from the high pressure side to one of the first or the second control port.