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.

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 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.

The present invention relates to a downhole hydraulic pump for providing fluid pressure during downhole operations, comprising a pump housing, a cam shaft rotatably arranged in the pump housing and having a longitudinal spin axis, the cam shaft comprising a shaft and a cam lobe arranged on the shaft, a radially arranged piston having a housing end and a cam end, a piston housing arranged in the pump housing, an inlet valve arranged in an inlet in the piston housing, an outlet valve arranged in an outlet in the piston housing, and a piston spring arranged in the pump housing for moving the piston away from the piston housing, wherein the piston housing is rotatably connected to the pump housing enabling rotation of the piston housing around a piston housing rotation axis parallel to the longitudinal spin axis of the cam shaft.

A radial piston machine includes a housing, rotor, first braking member, and brake ring with a second braking member. The rotor is mounted in the housing to be rotatable relative to an axis of rotation, and has an end face facing in a direction of the axis of rotation. The first braking member is positioned on the end face. The housing has a body defining a ring-shaped extension relative to the axis of rotation. The brake ring is positioned to surround the extension and is configured to be movable in the direction of the axis of rotation so as to bring the second braking member into braking engagement with the first braking member. The brake ring is further configured to positively engage with an inner radial side of the extension to limit a twisting between the housing and brake ring.

A radial piston pump 101 comprising a rotor 103 is disclosed. The rotor 103 includes a drive shaft 105 arranged to transmit rotary motion to or from the pump 101 and a piston housing 102 including at least one piston chamber 104, the at least one piston chamber 104 being arranged to receive a piston 108. The drive shaft 105 and the piston housing 102 are integrally formed.

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.

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 radial piston machine includes a housing, rotor, first braking member, and brake ring with a second braking member. The rotor is mounted in the housing to be rotatable relative to an axis of rotation, and has an end face facing in a direction of the axis of rotation. The first braking member is positioned on the end face. The housing has a body defining a ring-shaped extension relative to the axis of rotation. The brake ring is positioned to surround the extension and is configured to be movable in the direction of the axis of rotation so as to bring the second braking member into braking engagement with the first braking member. The brake ring is further configured to positively engage with an inner radial side of the extension to limit a twisting between the housing and brake ring.

The invention relates to a hydraulic machine (100) comprising:a distribution cover (2.3);a distributor (16);a displacement selection drawer (35) mounted so as to slide between a first position in which the machine is configured to operate with a first displacement and a second position in which the machine is configured to operate with a second displacement different from the first displacement; anda direction changing drawer (26) mounted so as to slide between a first position in which the machine is configured to exert a torque in a first direction about an axis of rotation (10) and a second position in which the machine is configured to exert a torque in a second direction, the direction changing drawer (26) being mounted so as to slide along an axis (42) at a distance from the axis of rotation (10), the direction changing drawer extending:in a wall of the distributor (16); orin a wall of the distribution cover and outside the displacement selection drawer (35).