A closure element for a fluid end assembly that has two or more recessed grooves formed in its outer surface. The grooves are axially offset. A seal is placed in one and only one of the grooves. As wear occurs, the seal is relocated to one of the other grooves. Instead of a series of axially offset grooves in a single closure element, a kit may be formed from two or more otherwise identical closure elements, each with a single recessed groove at a different axial position. Another closure element has a series of ledge-like surfaces defining spaces within which a seal may be received. One outer surface surrounds one or more of the other surfaces. A seal is placed in one and only one of the spaces. As wear occurs, the seal is relocated to one of the other spaces.

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).

An aircraft engine has a hollow driveshaft with a spool coaxial with the driveshaft and extending through the driveshaft to rotate independently of the driveshaft. A first harmonic cam is mounted on the driveshaft and a second spaced apart harmonic cam is mounted on the spool. At least one combustion cylinder is positioned between the cams along a combustion cylinder axis that is parallel with but radially spaced apart from the driveshaft. A piston assembly is disposed in each end of the combustion cylinder, with each piston assembly engaging a separate cam. A high-pressure compressor turbine is mounted on the driveshaft and driven by movement of a piston assembly, compressing air for the combustion cylinder. A rotating component is mounted on the spool and driven by movement of the other piston assembly. The rotating component may be another compressor turbine, a drive turbine, a fan or a propeller.

A hydrostatic piston machine unit, which is in particular designed as a hydrostatic axial piston machine unit, comprises at least two driving mechanisms that can be driven synchronously and have displacement pistons which each perform a reciprocating motion in operation and are provided for delivery into a common pressure line. The hydrostatic piston machine unit has a jointly assigned precompression volume for the at least two driving mechanisms.

A hydrostatic axial piston machine includes a pressing pressure chamber for the cylinder drum which is supplied with pressing pressure from a circular-arc-like elongate hole of a distributor plate or from a plurality of connection channels of the cylinder drum. The pressing pressure chamber is delimited radially outwardly by the cylinder drum and radially inwardly by the drive shaft. The pressing pressure chamber is delimited axially at both sides by seals which are both arranged between the radially inner rotating drive shaft and a radially outer stationary component. The radially outer component may be the cylinder drum or, in the case of the distributor-plate-side seal, also a gap seal between the drive shaft and a bearing bush of the distributor plate. Both seals are arranged at the distributor plate side with respect to a tooth arrangement or a retraction ball.

The present disclosure relates to an axial piston machine, such as a pump or motor. The axial piston machine, in on example, includes a pivotable displacement adjustment plate, the displacement adjustment plate having a first side supported by a first hydrostatic support arrangement and a second side supported by a second hydrostatic support arrangement. Further, in the axial piston machine one or both of the hydrostatic support arrangements include a large area support and a small area support which can be fluidly separated from each other.

A valve assembly is adjustable in three independent ways allowing it to provide a variable input volume. The valve assembly has a base and an entrance plate. An outer guide, an inner guide and a shaft, each with a passage, are held together and the shaft is rotatable between the guides. The valve is open when the passages of the inner guide plate and shaft are aligned and closed when the passages are not aligned. The shaft RPM determines how many times per minute the valve opens. The open/closed ratio of the valve assembly determines how long the valve is open during each half revolution. The location of the shaft up or down in relationship to the inner guide determines what percentage of possible flow passes through the valve during each half revolution. The valve assembly can be used with either a gas or liquid medium.

The invention relates to a piston type axial expander (4) comprising: an intake cylinder head (10) for vapor under pressure comprising a vapor intake opening (100), an expansion zone comprising a plurality of cylinders (110), wherein a piston (111) sliding in each respective cylinder is connected to a shaft (40) by an inclined plate (20), each piston being parallel to said shaft. a plurality of poppet valves (12) arranged orthogonally to the shaft (40) in the intake cylinder head (10) allowing alternating intake of vapor into said cylinders (110), each valve (12) being controlled by a cam (21) arranged on the shaft (40), a lift mechanism (13) for each valve cooperating with the cam, a return mechanism for each valve.

The intake cylinder head (10) comprises: an enclosed and lubricated central zone (10A) comprising the cam and the lift and return mechanisms of the valves, a peripheral zone (10B) in which the intake opening (100) leads, extending around the central zone (10A).

A hydrostatic axial piston machine (1) has a cylinder barrel (7) with a plurality of piston bores having pistons (10) fastened in an articulated manner to a drive flange (3). For articulated fastening of the pistons (10) to the drive flange (3), ball joints (20) are provided that are formed by a spherical cap-shaped receptacle socket (3a) in an end surface (3b) of the drive flange (3) and a ball head (10a) that is operatively connected with the piston (10). The receptacle sockets (3a) are each in the form of hemispheres that extend to the ball equator, and on one end surface (3b) of the drive flange (3), in the vicinity of the receptacle sockets (3a), there is a retaining web (30) that extends beyond the ball equator of the hemisphere to grip the ball head (10a) at an angle of greater than 180°.

A variable stroke high pressure pump is disclosed. The pump uses a wobble plate design with dynamically variable tilt to provide continuous adjustment of pump stroke length and output. Dynamically variable tilt is accomplished using a linearly actuated tilt thruster rotationally coupled to the drive shaft to maintain a selected tilt of the wobble plate through the rotation of the wobble plate.