Abstract: A radial piston device includes a housing (102), a pintle (110) attached to the housing (102) and having a pintle shaft (112), a rotor (130) rotatably mounted on the pintle shaft (112) and having cylinders (132), pistons (150) displaceably received in the cylinders (132), and a drive shaft (190) coupled to the rotor (130) and rotatably supported within the housing (102). The rotor (130) is made with two parts, such as a rotor body (250) and a rotor insert (252) received into the rotor body (250).

Abstract: A hydraulic motor (1), has an output shaft (3), a block cylinder (6), and high-pressure pistons (7) guided therein, and a block cylinder spring (9) and a valve plate (5). The block cylinder (6) exerts a contact-pressure force on the valve plate (5) by way of the charging pressure of the hydraulic oil in the block cylinder (6) and of the spring force of the block-cylinder spring (9). The contact-pressure force is counter-acted, when the hydraulic motor (1) is at a standstill, by a hydraulic pressure field which is built up on a surface (13) between the block cylinder (6) and the valve plate (5) via a valve device (12).

Abstract: A motor or pump includes a stator and a rotor supported for rotation with respect to the stator by a bearing arrangement. The rotor has a cylinder block thereon having radial cylinder bores equipped with radially reciprocable pistons. Rollers on the pistons abut a cam ring fixed to the stator so that the pistons to reciprocate radially to displace fluid when the rotor turns relative to the stator. The stator includes a control device fixed thereon having a pair of fluid passages therein. One side of the control device constitutes a distribution face with outlets therein connecting the fluid passages to the cylinder bores as the rotor rotates. A counterpart fastens to the rotor adjacent the opposite side of the control device so as to define an annular chamber therebetween. A shuttle valve operatively interposed between the passages and chamber ensures that the chamber remains in connection with the passage having the higher pressure.

Abstract: A reciprocating-piston-type refrigerant compressor having a cylinder block having a plurality of cylinder bores in which a plurality of pistons reciprocate to effect suction, compression and discharge of refrigerant gas in response to rotation of a drive shaft, a gas receiving chamber for receiving the refrigerant gas before compression, a gas discharge chamber for receiving the compressed refrigerant gas, and at least one rotary valve element mounted on the drive shaft to be rotatable with the drive shaft and having a suction passageway for providing a fluid communication between the gas receipt chamber and each of a compression chambers formed in the plurality of cylinder bores so that the refrigerant gas before compression is sequentially drawn into the compression chambers during the rotation of the rotary valve element.

Abstract: A hydro-mechanical transmission 10 having fluid motor 48 that is entirely rotatable to eliminate the need for separate gearing is disclosed. The gearless hydro-mechanical transmission 10 provides a variable speed and torque output from an external mechanical power source 14 and an external hydraulic power source 20.

Abstract: A refrigerant gas suction valve mechanism for a reciprocating piston type compressor is disclosed. The mechanism has a drive shaft rotatably disposed in a gas receiving chamber where uncompressed gas is introduced, Double- headed pistons provided in cylinder bores compress the gas when the pistons move from the bottom dead center to the top dead center. A suction port selectively permits and blocks communication between the suction passage and the compression chambers. A resilient member holds a rotary valve in contact with an inner wall of a recessed chamber with predetermined force. The suction port is maintained at a predetermined distance from a point where the pistons reach the top dead center so that the suction port is closed by the pistons before the pistons reach the top dead center.

Abstract: An axial piston machine having a longitudinally movable rotary cylindrical drum with cylindrical bores arranged concentrically to the axis of rotation of the drum. A longitudinally sliding piston located in each bore and lying against a control surface in contact with the drum. The pistons have an end in contact with a control surface that can be positioned diagonally to the axis of rotation of the drum and said cylindrical bores are provided with openings connecting to control channels in the control surface. Additional piston surfaces are provided in a cavity formed in the cylindrical drum for controlling the pressing force of the cylindrical drum on the control surface.

Abstract: A hydraulically operated continuously variable transmission comprising a hydraulic motor of the variable displacement type having a motor cylinder coupled to an output shaft and including motor plungers slidably disposed respectively in a number of cylinder holes defined in an annular pattern surrounding the axis of rotation of the motor cylinder, and a hydraulic pump coupled to an input shaft. The hydraulic motor and hydraulic pump are interconnected by a closed hydraulic circuit in which the flow of working oil is controlled by a distribution ring which is relatively rotatably and slidably held against an end surface of the motor cylinder for successively switching the introduction of working oil into the cylinder bores and the discharge of working oil from the cylinder bores in response to rotation of the motor cylinder. The distribution ring has an asymmetrical hydraulic pressure bearing area in order to minimize forces tending to tilt the distribution ring relative to the motor cylinder end surface.

Abstract: A fluid machine such as a pump, compressor, engine, motor or transmission has working chambers in a rotor and a central rotor-hub is provided in the rotor for the reception of a control pintle therein. The control pintle has control ports for the control of flow of fluid into and out of the working chambers of the rotor. Pressure fields form in the clearance between the rotor hub and the control pintle especially around the control ports. Leakage flows from the pressure fields through portions of the clearance between the rotor--hub and the control pintle which reduces the efficiency of the machine. Therefore means are provided in the control pintle to press those portions of the faces of the rotor hub and of the control pintle, which have those local pressure fields, together or to narrow the clearance between these faces in the respective areas where those pressure fields are located in order to reduce the leakage through the clearance between the faces of the rotor hub and the control pintle.

Abstract: A hydraulic transmission device operable to translate hydraulic energy into mechanical energy and vice versa. The device has a housing 14 having a close end portion and an open end portion in the longitudinal direction. The housing supports therein a drive shaft 11, a retainer 12, and a cylinder block 13 which have an integral structure. A recess is formed at a substantially central location of the end surface of the cylinder block 13 that is on the side of an open end of the housing, and a cover 15 closing the open end of the housing has a protruding portion 15A which extends through a port plate 23 to be engaged with the recess of the cylinder block through a bearing 17. A plurality of pistons are disposed in the cylinder block and are kept in tight engagement with a swash plate fixed to the closed end portion of the housing at a constant tilt angle. The device acts as either a swash plate type axial piston pump or motor of this type as the drive shaft rotates.

Abstract: An axial piston machine having an inclined axis construction, including a cylinder drum pivotally arranged within a housing, and a swivel carriage located opposite to the cylinder drum and which is supported in a sliding guide, which contains the control surface as well as the reniform control recesses on the pressure and suction sides and connects these with, respectively, a pressure or suction passageway communicating in one of the sliding guide surfaces. Included is an adjusting arrangement for setting the angular position of the cylinder drum, consisting of a displaceable setting element arranged on the housing generally in parallel with the drive shaft and of an angle lever supported in the housing so as to be pivotable about the swivel axis of the cylinder drum, whose first lever arm is articulated on the setting element and whose second lever arm engages on the swivel carriage.

Abstract: The hydrostatic piston machine is provided with hydrostatic bearing pockets at least one of which is provided with an unthrottled flow of high-pressure medium while at least one other pocket is provided with a throttled flow of high-pressure medium. And the pockets are sized relative to each other so that the pockets receiving the unthrottled flow compensate for 70% to 95% of the force on the bearing while the pockets receiving the throttled flow compensate for 30% to 5% of the bearing forces applied.

Abstract: A floating bearing ring is disposed between each bearing surface of the fixed pin and the guide member for the pistons and in spaced relation to each. The clearance of the bearing rings from the pin bearing surfaces is less than the clearance of the bearing rings from the guide member. Upon heating of the pin, the bearing rings simultaneously heat up to the same temperature to maintain their clearance. This prevents seizing of the bearing rings and, in turn, the guide member on the pin during use.