There is provided a wobble plate piston water pump for use in a pressure washer and driven by a driving source, the water pump includes a pump body, a wobble plate, four or more pistons and a water passage defined by a water inlet and a water outlet. The driving source being electric powered and having a power consumption of less than or equal to a 15 ampere draw at 120 volts or 220 volts or the driving source being gas powered and having an engine displacement of less than or equal to 250 cubic centimetres.

A cylinder block (1) for a compressor has a central opening (3) for accommodating a drive shaft of a drive unit and defines a central axis of the cylinder block (1) with a plurality of cylinder bores (2) arranged around the central opening and each of the cylinder bores (2) adapted for accommodating a piston (14).The cylinder block (1) also has at least one stop (10) on a drive side of the cylinder block (1) with the stop (10) arranged within a triangular area which is delimited by the central opening (3) and the two adjacent cylinder bores (2).

A hydrostatic axial piston machine (1) has a housing (2), a rotatable drive shaft (4) mounted in the housing (2) by a bearing device (5) that comprises at least one roller bearing (5a; 5b), a cylinder drum (7) having at least one piston bore (8), and a longitudinally displaceable piston (10) in each piston bore. A spray jet lubrication system (50) for the roller bearing (5a; 5b) includes at least one lubricant spray jet (51a; 51b) directed toward the area of an axial edge (30; 32) of an inner ring (5c; 5d) of the roller bearing (5a, 5b) with which the roller bodies of the roller bearing (5a, 5b) are in contact via an end surface.

A hydroelectric power system and pump suitable for the system are disclosed which can make efficient use of the energy available in water flows with considerably variable flow rates. A simple, compact variable displacement axial piston pump can be operated so as to provide an essentially constant output pumping pressure and variable output volume that varies efficiently in accordance with water flow rate. The system is particularly suitable for shoreline tidal power generation and provides firm power output throughout the tidal slacks occurring during the tidal reversals.

A hydroelectric power system and pump suitable for the system are disclosed which can make efficient use of the energy available in water flows with considerably variable flow rates. A simple, compact variable displacement axial piston pump can be operated so as to provide an essentially constant output pumping pressure and variable output volume that varies efficiently in accordance with water flow rate. The system is particularly suitable for shoreline tidal power generation and provides firm power output throughout the tidal slacks occurring during the tidal reversals.

A slipper retainer ball of a hydraulic unit having an aperture passing through a body, the body having a flat bottom surface, a flat top surface, an external curved surface, and an interior profiled surface that extends in an axial direction from the bottom surface to the top surface. The interior profiled surface includes a first surface extending parallel to the axis from the bottom surface in the axial direction, a second surface extending perpendicular to the axis from the first surface and outward toward the external curved surface, a third surface extending from the second surface axially at a first angle, a fourth surface extending from the third surface in the axial direction, and a fifth surface extending from the fourth surface to the top surface at a second angle that is skew from the axis. The axial thickness of the body is about 0.471 inches.

It is an object of the present invention to provide a semispherical shoe which can be prevented from being subjected to seizure even in a dry lubrication state in which there is no lubricating oil at the start time of an operation of a swash plate compressor, is excellent in its sliding contact property and load resistance, does not deteriorate in its lubricating property due to generated frictional heat, does not subject a resin layer to peeling from a base material, and ensures sufficient durability. It is another object of the present invention to provide a swash plate compressor in which a lubricating film is not formed on a sliding contact surface of the swash plate and that of a piston owing to the use of the semispherical shoe. A semispherical shoe (4) is subjected to sliding contact with the swash plate of the swash plate compressor and the piston thereof. Abase material (5) consists of a metallic member. A resin layer (6b) is formed on a surface of a planar part (4b) to be subjected to sliding contact with the swash plate. A resin layer (6a) is formed on a surface of a spherical part (4a) to be subjected to sliding contact with the piston. The resin layer (6a) and the resin layer (6b) are integral with each other. At least one portion of the base material (5) is not covered with the resin layer (6) and is exposed.

A submersible pumping system includes an electric motor and a pump driven by the electric motor. The pump includes a rotatable shaft driven by the motor, one or more piston assemblies configured for linear reciprocating motion and a mechanism for converting the rotational movement of the shaft to linear reciprocating movement in the piston assemblies. In one aspect, the mechanism for converting the rotational movement of the shaft includes a tilt disc assembly. In another aspect, the mechanism for converting the rotational movement of the shaft includes a camshaft assembly.

A bent axis plunger-type variable hydraulic motor pump, including a cylinder body, a plunger, a ball connecting rod, a plunger spherical hinge, a multistage ball track spherical hinge shaft, a multistage ball track bearing ring, a retainer plate, an oil distributing plate, an oil distributing plate pin shaft, a suspension circle, a bushing bearing ring, a box bushing shaft, a box, a large variable ball connecting rod assembly, and a small variable ball connecting rod assembly. The large and small variable ball connecting rod assemblies are mounted on the box. The multistage ball track spherical hinge shaft is supported on the multistage ball track bearing ring, and a multistage rolling element holder in which a rolling element is provided is mounted in the multistage ball track spherical hinge shaft. Two ends of the ball connecting rod are hingedly connected to the multistage ball track spherical hinge shaft and the plunger.

A bent axis plunger-type variable hydraulic motor pump, including a cylinder body, a plunger, a ball connecting rod, a plunger spherical hinge, a multistage ball track spherical hinge shaft, a multistage ball track bearing ring, a retainer plate, an oil distributing plate, an oil distributing plate pin shaft, a suspension circle, a bushing bearing ring, a box bushing shaft, a box, a large variable ball connecting rod assembly, and a small variable ball connecting rod assembly. The large and small variable ball connecting rod assemblies are mounted on the box. The multistage ball track spherical hinge shaft is supported on the multistage ball track bearing ring, and a multistage rolling element holder in which a rolling element is provided is mounted in the multistage ball track spherical hinge shaft. Two ends of the ball connecting rod are hingedly connected to the multistage ball track spherical hinge shaft and the plunger.