An axial piston pump having several pistons has a magnetic encoder (5), which is arranged on a swash plate, and a magnetic field sensor, which is arranged in such a way that it faces towards the magnetic encoder (5). The magnetic encoder (5) has at least two permanent magnets (2, 3) and a plate (4) which consists of a ferromagnetic material. The permanent magnets (2, 3) are arranged on the plate (4) in such a way that they each faces a magnetic pole towards the plate (4), and this pole is at least partially covered by the plate (4) in each case.

In a variable displacement type swash plate compressor, a connecting mechanism that connects a movable body and a swash plate includes a first arm having a first guide surface and a second arm having a second guide surface. The first and second arms extend from the movable body toward the swash plate and disposed on opposite sides of an imaginary plane that is defined to extend passing through a top dead center portion and an axis of rotation. The first arm and the second arm have a first opening and a second opening, respectively, that are open in a direction opposite to a direction in which a link pin moves on the first guide surface and the second guide surface with an increase of the inclination angle of the swash plate.

A variable displacement type swash plate compressor includes a housing having therein a suction chamber, a discharge chamber, a control pressure chamber, a shaft hole, and cylinder bores. The compressor further has a drive shaft, a swash plate, an inclination angle changing mechanism, pistons, introduction passages, and a valve mechanism. The valve mechanism includes a valve element is disposed in a passage connecting the control pressure chamber and the suction chamber. The valve element is integrally rotatable with the drive shaft and axially movable by a pressure difference across the valve element. An opening of the residual gas bypass passage is changed by the axial movement of the valve element. The valve element selectively connects and disconnects the introduction passages with the residual gas bypass passage.

Disclosed are hollow pistons made from a single piece of starting material and methods of manufacturing unitary hollow pistons from a single solid rod as a starting material.

The invention relates to a swashplate (5) for a swashplate compressor (1) comprising a main swashplate body (8), which is made from a sintering material, and to a method for producing the swashplate (5).

An end part of a piston on a front edge side is formed so as to have a crowning of a 1.2-order to 2.5-order curve where a length is 10% or more and 80% or less of a length of a cylindrical part and a height is 10% or more and 160% or less of a clearance. An end part of a cylinder block on a front edge side is formed so as to have a crowning of a 1.2-order to 2.5-order curve where a length is 8% or more and 60% or less of the length of a cylindrical part and a height is 12% or more and 125% or less of the clearance.

An actuator of a variable displacement swash compressor includes a partitioning body that is movable along the axis of a drive shaft, a movable body that changes the inclination angle of a swash plate, and a control pressure chamber defined by the partitioning body and the movable body. The movable body is moved by drawing refrigerant in the control pressure chamber from a discharge chamber. The swash plate is configured to contact and move the partitioning body as the inclination angle increases.

Disclosed are a pump body assembly and a fluid machine. The pump body assembly includes a rotation shaft and a piston provided with a sliding hole, at least a portion of the rotation shaft penetrates into the sliding hole, during rotation of the piston with the rotation shaft, and the sliding hole is in sliding fit with the rotation shaft, the piston is provided with a piston communication passage communicated with the sliding hole. The pump body assembly can solve the problem that the piston impedes a flow of oil liquid during use of a rotary cylinder compressor.

A pressure-acting chamber is defined by a first cylinder block and a spacer. The pressure-acting chamber communicates with a discharge chamber via a supply passage. A load based on the pressure difference between the pressure-acting chamber and a swash plate chamber is applied to a rotary shaft and acts toward a second thrust bearing.

Disclosed are hollow pistons made from a single piece of starting material and methods of manufacturing hollow pistons from the single piece of starting material.