A piston unit includes a piston which has a rolling element seat configured to rotatably support a rolling element. The rolling element seat has a bearing surface with a surface coating composed of a polymer compound or with a ceramic surface coating.

It is intended to provide a vehicle comprising a fluid working machine which can reduce wear of parts and be produced at low cost. The fluid working machine 11, 12 is provided with an eccentric cam 17, a piston 18A to 18F, a cylinder 19A to 19F, a drive rod 20A-20F having an engaging part 24 engaging with the piston and a contact part 25 contacting the eccentric cam 17, a holding member 34A to 34F surrounding the drive rod, a pressing member 40A to 40F for pressing up the holding member in a radially outward direction, and at least one holding ring 41 for holding the holding member from the outside.

A reciprocating piston internal combustion engine includes at least one first, one second and one third cylinder and has a crank mechanism having a crankshaft, which is rotatably mounted in a crankcase, having a first, a second and a third crankpin. A first connecting rod having a first piston for the first cylinder is allocated to the first crankpin. A second connecting rod having a second piston for the second cylinder is allocated to the second crankpin. A third connecting rod having a third piston for the third cylinder is allocated to the third crankpin. The crankpins are arranged successively in an axial direction of the crankshaft, wherein the cylinders are arranged in a fan shape.

A reciprocating piston internal combustion engine includes at least one first, one second and one third cylinder and has a crank mechanism having a crankshaft, which is rotatably mounted in a crankcase, having a first, a second and a third crankpin. A first connecting rod having a first piston for the first cylinder is allocated to the first crankpin. A second connecting rod having a second piston for the second cylinder is allocated to the second crankpin. A third connecting rod having a third piston for the third cylinder is allocated to the third crankpin. The crankpins are arranged successively in an axial direction of the crankshaft, wherein the cylinders are arranged in a fan shape.

A radial piston device includes a housing and a pintle fixed thereto that includes an inlet and an outlet, each aligned with a pintle axis. A rotor is rotatably disposed around the pintle and includes radially oriented cylinders. A piston is axially displaceable in each cylinder and includes a head defining a spherical contact surface. A thrust ring is rotatably disposed within the housing about the rotor and is in contact with each piston, such that a rotation of the rotor rotates the thrust ring. An inner surface of the thrust ring defines a toroidal contact surface. A contact location between the spherical contact surface and the toroidal contact surface varies as the rotor rotates about the pintle. A drive shaft is engaged with the rotor, such that a rotation of the rotor rotates the drive shaft.

Mounting structure for housing-free hydraulic axial piston machines of the bent axis or swash plate design, having a closing plate on which a cylinder block unit with displacing pistons arranged therein is supported, and having a drive or driven shaft. The mounting structure here is designed in the manner of a basket and has a receptacle for the drive or driven shaft and at least two struts which are in each case connected at one end to the receptacle and at the other end to the closing plate in such a manner that the closing plate, the cylinder block unit and the drive or driven shaft are heldanalogously as in a housingin a functionally ready position.

A hot fluid expansion engine has a plurality of actuator modules arranged in a star configuration around a central shaft. Each module includes a drive piston defining a working chamber of variable volume in the first enclosure; a movable displacement piston subdividing a second enclosure into a low temperature chamber of variable volume and a high temperature chamber of variable volume with the high temperature chamber communicating with a unit of a fluid heater device and the low temperature chamber communicating with the working chamber; and a fluid circulation circuit extending between the fluid heater device and the working chamber. The drive piston and the displacement piston of each actuator module are connected to the central shaft via respective first and second eccentric transmission devices suitable for imparting reciprocating motion in translation to each of the pistons with a phase lag of 90.

A hot fluid expansion engine has a plurality of actuator modules arranged in a star configuration around a central shaft. Each module includes a drive piston defining a working chamber of variable volume in the first enclosure; a movable displacement piston subdividing a second enclosure into a low temperature chamber of variable volume and a high temperature chamber of variable volume with the high temperature chamber communicating with a unit of a fluid heater device and the low temperature chamber communicating with the working chamber; and a fluid circulation circuit extending between the fluid heater device and the working chamber. The drive piston and the displacement piston of each actuator module are connected to the central shaft via respective first and second eccentric transmission devices suitable for imparting reciprocating motion in translation to each of the pistons with a phase lag of 90.

Improved radial engine configurations where the pistons and their associated connecting rods interface with a center crankshaft by the use of slipper bearings, which only contact a portion of the center crankshaft throw. The improved radial engine crankshaft interface includes at least one connecting rod with a bearing that encircles the center crankshaft throw, and acts as a retaining ring for the slipper bearings.

A crank circular slider mechanism that includes a multi-row reciprocating motion part and a one-row reciprocating part. The multi-row reciprocating motion part has a guiding part divided by a longitudinal groove into two rows parallel to each other, each of which has a hole for a circular slider. The one-row reciprocating motion part has a guiding part which can be inserted into the longitudinal groove of the multi-row reciprocating motion part along the thickness direction, so as to vertically traverse the multi-row reciprocating motion part. The guiding part of the one-row reciprocating motion part includes a hole receiving a middle circular slider. Two circular sliders are mounted in the same phase; the middle circular slider is sandwiched therebetween and is located with a 180 degree phase difference compared to them. Adjacent circular sliders are secured to each other.