A hydrostatic radial piston machine is useable inversely. The hydrostatic radial piston machine has a distributor in which a flushing valve, a pressure-maintaining valve connected downstream of the flushing valve, and two nonreturn valves are arranged.

A hydraulic machine includes radial cylinders including, oscillating radial cylinders arranged in a crown or star of cylinder-piston units, the pistons of the groups are made slidable on a crankshaft or with a cam, or on interposed members concentric to it, and realizing the reciprocating motion in the oscillating cylinders. The oscillating cylinders are placed in contact with a surface of distribution concentric or corresponding to the surface of oscillation of the respective cylinder on which a distributor body is placed separate from the machine body and housed in a seat in the body, or part fixed to the body, of the hydraulic machine, and each distributor body is mobile in its seat under the action of the pressure of liquid in connection on the back surface of the distributor body against the surface of distribution of the oscillating radial cylinder subject to the distribution.

A hydraulic pump motor includes: a cylinder block; a plurality of cylinder bores; a port block and a valve plate, the valve plate being provided with a high pressure port and a low pressure port, the port block being provided with a discharge oil passage and a suction oil passage, a piston disposed in each cylinder bore, and oil flowing through the discharge oil passage and the suction oil passage. Further, the valve plate is provided with a reproduction port at a bottom dead center side position, the port block is internally provided with a reproduction oil passage, and the reproduction oil passage passes through a first region on a side of the high pressure port of the virtual plane and passes through a second region on a side of the low pressure port of the virtual plane in the port block.

An assembly including a hydraulic device around a second axis of rotation by means of a proximal rolling-element bearing and a distal rolling-element bearing, the hydraulic device including a shaft, a multi-lobe cam, a cylinder block and a distributor, and a pivoting element adapted to be mounted on an axle, and movable in rotation relative to the hydraulic device around a first axis of rotation. Views along a plane defined by the second axis of rotation and the first axis of rotation, the proximal rolling-element bearing and the distal rolling-element bearing are positioned on either side of the first axis of rotation, in that the cylinder block is positioned between the first axis of rotation and the proximal rolling-element bearing.

An axial-type hydraulic pump/motor in which a cylinder block with a plurality of cylinder bores formed around a rotation axis slides with respect to a valve plate that has a valve plate discharge port and a valve plate suction port, and controls the amount of reciprocation of a piston in each cylinder bore depending on the inclination of a swash plate. Based on the rotational direction of the cylinder block, an opening shape of an end portion on the front side in the rotational direction of a cylinder port and an opening shape of an end portion on the rear side in the rotational direction of the valve plate suction port PB1 have the same shape or partially have the same shape.

The hydraulic machine includes a cam and a cylinder block with pistons co-operating with cam lobes, each of which has two ramps extending between top and bottom dead center arcs. The cylinders are connected in alternation to a feed and to a discharge, in sequences separated by switchover stages including an isolation stage during which they are isolated relative to the feed and discharge main ducts. The angular position of the start or of the end of at least one first isolation stage relative to the corresponding dead center arc is different from the angular position of the start or of the end of at least one second isolation stage relative to its corresponding dead center arc, both of these dead center arcs being top dead center arcs or both of them being bottom dead center arcs.

A hydraulic machine comprising a drum (12) rotated by an input shaft, comprising cylinders (14) distributed around the shaft, each receiving a piston that slides on the basis of the rotation of the shaft, each cylinder opening at an opening (30) on a transverse face of the drum bearing on a plate having inlet and outlet manifolds, the openings (30) comprising, relative to the cylinders (14) of same, angular offsets comprised within a total offset range, characterized in that the offsets of the openings (30) are disposed at one end or the other of this offset range.

A hydraulic motor includes a motor mechanism that rotates by hydraulic liquid pressure led from a hydraulic liquid pressure source. The hydraulic motor includes a casing that defines a casing chamber which accommodates the motor mechanism, a brake mechanism that brakes the rotation of the motor mechanism, a brake release actuator that releases the braking of the brake mechanism by a brake release pressure led from the hydraulic liquid pressure source, and a throttle passage that is in communication with the casing chamber and extracts a portion of hydraulic liquid that is led into the brake release actuator and leads it to the casing chamber.

The invention relates to a hydraulic machine (100) comprising:a distribution cover (2.3);a distributor (16);a displacement selection drawer (35) mounted so as to slide between a first position in which the machine is configured to operate with a first displacement and a second position in which the machine is configured to operate with a second displacement different from the first displacement; anda direction changing drawer (26) mounted so as to slide between a first position in which the machine is configured to exert a torque in a first direction about an axis of rotation (10) and a second position in which the machine is configured to exert a torque in a second direction, the direction changing drawer (26) being mounted so as to slide along an axis (42) at a distance from the axis of rotation (10), the direction changing drawer extending:in a wall of the distributor (16); orin a wall of the distribution cover and outside the displacement selection drawer (35).