A hydraulic machine (1) has a working section (6) and a fluid control section (28). The fluid control section includes a spool (3) that is rotatable in a cylindrical bore (30) about an axis (4). A distributor plate (18) extends intermediate of the control section and the working section. The spool includes an axial recess (10) which is axially bounded by a radially extending annular wall (44). A front face (48) of the annular wall rotates in abutting engagement with a plate face contact area (50) of the distributor plate. Hydraulic fluid flows through at least one groove (52) that extends radially and circumferentially across the abutting areas of the spool and the distributor plate to provide lubrication and heat absorption.

A hydraulic machine (1) has a working section (6) and a fluid control section (28). The fluid control section includes a spool (3) that is rotatable in a cylindrical bore (30) about an axis (4). A distributor plate (18) extends intermediate of the control section and the working section. The spool includes an axial recess (10) which is axially bounded by a radially extending annular wall (44). A front face (48) of the annular wall rotates in abutting engagement with a plate face contact area (50) of the distributor plate. Hydraulic fluid flows through at least one groove (52) that extends radially and circumferentially across the abutting areas of the spool and the distributor plate to provide lubrication and heat absorption.

An actuator (1) having an energy accumulator (6), with which an emergency drive (5) can be supplied, is configured to be tensioned by an electric motor (2). The motor (2) displaces at least one engaging element (41, 42) of the energy accumulator (6), on which a restoring force of the energy accumulator (6) acts, along an actuating travel in normal operating mode.

An actuator (1) having an energy accumulator (6), with which an emergency drive (5) can be supplied, is configured to be tensioned by an electric motor (2). The motor (2) displaces at least one engaging element (41, 42) of the energy accumulator (6), on which a restoring force of the energy accumulator (6) acts, along an actuating travel in normal operating mode.

An example valve includes: a seat member; a spool configured to be seated on the seat member to block fluid flow from a first port to a second port when the valve is in a closed state, wherein fluid at the first port applies a fluid force on the spool; a spring applying a biasing force on the spool toward the seat member, wherein as the fluid force overcomes the biasing force, the spool moves in the proximal direction off the seat member, thereby allowing fluid flow from the first port to the second port through a flow area formed between the spool and the seat member; a turbine configured to rotate as fluid flowing through the flow area flows downstream across the turbine; and an electric generator coupled to the turbine, such that rotation of the turbine causes the electric generator to generate electric power.

An example valve includes: a pressure compensation spool configured to be subjected to a first fluid force of fluid received at a first port acting in a proximal direction; a pressure compensation spring disposed in a pressure compensation chamber and applying a biasing force on the pressure compensation spool in a distal direction; a turbine configured to rotate as fluid flows through the valve; and a flow area configured to throttle fluid flow from the first port to the pressure compensation chamber, wherein fluid in the pressure compensation chamber applies a second fluid force on the pressure compensation spool in the distal direction, such that the pressure compensation spool moves to a particular axial position based on force equilibrium between the first fluid force, the second fluid force, and the biasing force to throttle fluid flow from the pressure compensation chamber to a second port.

An example valve includes: a pressure compensation spool configured to be subjected to a first fluid force of fluid received at a first port acting in a proximal direction; a pressure compensation spring disposed in a pressure compensation chamber and applying a biasing force on the pressure compensation spool in a distal direction; a turbine configured to rotate as fluid flows through the valve; and a flow area configured to throttle fluid flow from the first port to the pressure compensation chamber, wherein fluid in the pressure compensation chamber applies a second fluid force on the pressure compensation spool in the distal direction, such that the pressure compensation spool moves to a particular axial position based on force equilibrium between the first fluid force, the second fluid force, and the biasing force to throttle fluid flow from the pressure compensation chamber to a second port.

A multi-degree-of-freedom automatic center-adjusting device, a hydraulic quick-coupling device, and rescue equipment are provided. The automatic center-adjusting device includes an active coupling valve set, a spring, and a dynamic adjustment swing rack. A first end of the dynamic adjustment swing rack is fixed to operation tools, and a second end of the dynamic adjustment swing rack is connected to the active coupling valve set through the spring. The dynamic adjustment swing rack includes a frame, a limit slot, and a spring limit cylinder, wherein the frame is used to support and fix the active coupling valve set, the limit slot is used to define a limit activity position of the active coupling valve set, and the spring limit cylinder is used to constrain the spring. The automatic center-adjusting device is used to solve technical problems of position errors and a center mismatch in a coupling process.

A heavy equipment recovery winch system includes a winch assembly mountable to a drive end of a heavy equipment vehicle, a hydraulic assembly and a fairlead assembly. The hydraulic assembly is mounted to a portion of the heavy equipment vehicle and the hydraulic assembly is operatively connected to the winch assembly. The fairlead assembly is mountable to the drive end of the heavy equipment vehicle to assist with guiding a cable from the winch assembly.

A vehicle including a control valve to lift and lower a boom. The vehicle further includes a control circuit to control a speed of the boom lowering via a pressure compensator that balances a first pressure signal downstream of a control valve during the boom lowering and a second pressure signal from a hydraulic user interface so that, upon increasing of the first pressure signal during the boom lowering, the control valve progressively closes.