The assembly may include a cylinder block, a plurality of pistons, and a holding element, the holding element extending over all or part of the outer periphery of the cylinder block. The holding element may include a plurality of guide portions, each partially blocking a recess of the cylinder block so as to come into contact with a planar end of the crown of a piston to guide in the translation of each piston in their respective recesses. The holding element may include two indexing means cooperating with two indexing means of the cylinder block so as to hold the holding element under a traction force when positioned around the cylinder block.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

A radial piston hydraulic motor comprising a box frame with a cam ring connected thereto, pistons in a piston frame and press rollers in the pistons, which press rollers can be pressed by means of the pressure of a hydraulic fluid, such as hydraulic oil, against an inner surface of the cam ring. The piston frame comprises connections between the interior space and passages, and a shutter valve is provided within each connection for controlling the hydraulic fluid flow through the connection between the passages and the interior space. The shutter valve is arranged to allow hydraulic fluid to flow from the passage into the interior space, when the pressure in the working pressure inlet passage, in the return passage and in the interior space is equal, i.e. the motor is in free-rotating state.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

An electric-to-hydraulic conversion machine includes an axial flux electric motor and a hydraulic pump. The motor includes a spindle, at least one rotor configured to rotate about the spindle, and at least one stator configured to drive rotation of the at least one rotor about the spindle. The hydraulic pump includes a piston block having a plurality of cylinders, a plurality of pistons each supported in one of the cylinders of the piston block, and a cam ring. The piston block is attached to the at least one rotor and is configured to rotate about the spindle with rotation of the at least one rotor. The cam ring is configured to radially drive the pistons during rotation of the piston block about the spindle, which drives a fluid flow.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

A hydraulic radial piston device includes a housing, a pintle having a pintle shaft, a rotor mounted on the pintle shaft and defining a plurality of cylinders, and a plurality of pistons displaceable in the cylinders. The radial piston device further includes a piston ring that provides an interface for the pistons. The radial piston device includes various configurations for improving the performance and efficiency of the device.

A radial piston hydraulic motor comprising a box frame with a cam ring connected thereto, pistons in a piston frame and press rollers in the pistons, which press rollers can be pressed by means of the pressure of a hydraulic fluid, such as hydraulic oil, against an inner surface of the cam ring. The piston frame comprises connections between the interior space and passages, and a shutter valve is provided within each connection for controlling the hydraulic fluid flow through the connection between the passages and the interior space. The shutter valve is arranged to allow hydraulic fluid to flow from the passage into the interior space, when the pressure in the working pressure inlet passage, in the return passage and in the interior space is equal, i.e. the motor is in free-rotating state.