Abstract: A hydraulic drive system includes a hydraulic pump, a boom-dedicated control valve, a turning-dedicated control valve, a boom-dedicated operation unit, a turning-dedicated operation unit, and a driving control unit.

Abstract: A fluid power system comprises a pump with multiple independently variable outlets, each of which is capable of delivering fluid in individually controllable volume units and a plurality of hydraulic loads. A system of switching valves is configured to create fluid connections between the pump outlets and the loads. A control system commands both the pump and the switching valves, so as to create valve state combinations to satisfy load conditions as demanded by an operator. The number of pump outlets connected to one or more of the loads is changeable to satisfy the flow required of the load due to the operator demand, each pump outlet being commanded to produce a flow depending on the status of other outlets connected a load to which the outlet is connected and the operator demand for that load.

Abstract: A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.

Abstract: A hydraulic actuator includes a cylinder, a pump, an electric motor and a central block. The mechanism or the rotating parts of the pump are directly installed in an interior of the block, and the drive shaft of the pump is correspondingly mounted in walls or in covers of the block.

Abstract: The invention relates to a hydraulic cylinder comprising a body (1) having a wall (3) that defines a cylindrical cavity (2), with a cylindrical cavity axis (X), in which a piston (4) is movably mounted, said piston (4) separating said cylindrical cavity (2) into two tight chambers (5, 6) that are isolated from each other, the wall (3) of the body comprising at least two passages (7, 8) for introducing or discharging a fluid into each of said two chambers (5, 6). The cylinder also comprises two end walls (17, 18) and a rigid rod (32) which is secured to the piston (4) and coaxial with the cylindrical cavity (2), said rod (32) passing through a passage opening (20) provided in one of the two end walls (17, 18). The cylinder is characterised in that it comprises a position sensor (38) comprising a sensor head (39), a sensor rod (40) which is secured to the sensor head (39) and around which a magnet (41) is fitted, and a connector (42) connected to said sensor head (39).

Abstract: A hydraulic system for powering a winch assembly of a work machine includes a hydraulic reservoir, a pump, a cooling system, a first path of travel, and a second path of travel. The first path of travel is disposed between the pump and the cooling system, and the winch assembly is powered by the hydraulic fluid moving along the first path of travel. The second path of travel is disposed between the pump and the cooling system. When the winch assembly is in an active condition, a first valve is in an open position such that the hydraulic fluid moves along the first path of travel and through the cooling system. When the winch assembly is in an idle condition, a second valve is in an open position such that the hydraulic fluid moves along the second path of travel and through the cooling system.

Abstract: A control arrangement (5) of a hydraulic system (1) is provided, said control arrangement (5) comprising a supply port arrangement having a high pressure port (6) and a low pressure port (7), a working port arrangement having two working ports (8, 9), a first valve (10) arranged between said high pressure port (6) and said working port arrangement (8, 9), a second valve (11) arranged between said low pressure port (7) and said working port arrangement (8, 9). Such a control arrangement should enhance the control of a hydraulic system.

Abstract: A pressure booster constituting a cylinder apparatus is provided with a first piston and a second piston that are coupled to each other by a rod. A connection member provided to the second piston is configured so as to be displaceable from a connection position to a blocking position as a result of the connection member making contact with a cylinder body when the second piston is displaced in a direction where a boosting chamber contracts, and so as to be displaceable from the blocking position to the connection position as a result of the connection member making contact with the cylinder body when the second piston is displaced in a direction where the boosting chamber expands.

Abstract: A cylinder actuator includes a body assembly and a piston assembly. The body assembly includes a first cylinder nested concentrically within a second cylinder. The piston assembly slides linearly within the first and second cylinders. The piston assembly includes a first piston assembly end and a second piston assembly end. The first piston assembly end includes first and second pistons. The first piston moves within the first cylinder. The second piston moves within the second cylinder. The piston assembly includes first and second piston rods. The first piston rod extends from the first piston through a first end of the first cylinder. The second piston rod extends from the second piston through a first end of the second cylinder. The piston rods are joined at the second end of the piston rod assembly located outside of the first and second cylinders.

Abstract: A piston pump includes a frame, a housing configured to be coupled to the frame via a fastener, an annular liner defining a chamber configured to receive a piston of the piston pump, and an annular liner lock flange circumferentially surrounding the annular liner. The annular liner lock flange includes a radially-extending portion configured to be positioned within a respective counterbore of the frame and a respective counterbore of the housing while the housing is coupled to the frame via the fastener to block relative movement between the liner lock flange, the frame, and the housing.

Abstract: An auxiliary power unit system for mobile service vehicles is provided that can provide DC power to DC-powered equipment. The system attaches to the power take-off port of the transmission and can provide power to the DC-powered equipment without idling the engine of the mobile service vehicle, thereby reducing fossil fuel consumption and engine exhaust emissions.

Abstract: A hydraulic system includes a control device to reduce a first movement speed to be lower than a second movement speed, the first movement speed being a speed at which a spool of a first control valve moves from a first supply position to a first stop position under a state where a second control valve is in the second supply position, the second movement speed being a speed at which the spool moves from the first supply position to the first stop position under a state where the second control valve is in the second stop position. The first supply position allows operation fluid to be supplied to a hydraulic actuator. The first stop position prevents the operation fluid from being supplied to the hydraulic actuator. The second stop position prevents the operation fluid from being supplied to a first fluid tube coupling a hydraulic pump to the hydraulic actuator.

Abstract: This disclosure relates to a hydraulic system for a hydro-mechanical machine comprising a rotary mechanism. The hydraulic system includes a primary accumulator configured to receive and store high-pressure fluid in response to stopping of the rotary mechanism. A control system coupled to the primary accumulator through a hydraulic supply circuit is configured to enable passage of the high-pressure fluid stored in the primary accumulator to a rotary control valve configured to control the rotary mechanism, through the hydraulic supply circuit, based on a predefined pressure threshold associated with the primary accumulator. A secondary accumulator coupled to the primary accumulator and the control system via the hydraulic supply circuit is configured to store surplus high-pressure fluid provided by the primary accumulator through the hydraulic supply circuit.

Abstract: A piston in which a solid lubricant resin layer made of a resin containing a solid lubricant is formed at a skirt portion. A guide groove absent area where no guide groove is formed, which is provided in a predetermined range of the solid lubricant resin layer at a center portion in a width direction. The guide grooves directing from the both ends in the width direction of the guide groove absent area to both ends in the width direction of the skirt portion. The end portions of the guide grooves extended to end edges of the solid lubricant resin layer to form open ends. The solid lubricant resin layer and the guide grooves are formed at least at a thrust side skirt portion. The guide grooves are formed in a shape inclined upward from the guide groove absent area toward the end edges of the solid lubricant resin layer.

Abstract: An axial piston machine of oblique axis design has a pivot angle that is adjustable via a set piston and a control valve and includes a first valve slide that is linearly movable relative to a first valve axis and is connected at two opposite ends to a first or a second fluid port. The first valve slide has a central region that defines a control point at which the lower of pressures at the first and second fluid ports act. The control point is connected via a fixed first throttle and a second throttle to a housing interior. A second valve slide that is linearly movable relative to a second valve axis is configured to adjust the second throttle. The first valve axis is arranged between the set piston and the control valve or a region of the control valve and is oriented transverse to the adjusting axis.

Abstract: A hydraulic pressure amplifier arrangement (1) is described comprising a supply port (A1), a pressure outlet (A2) connected to the supply port via check valve means (3), a tank port (B1), an intensifier section (5) having a high pressure piston (6) in a high pressure cylinder (7) which is connected to the pressure outlet (A2), a low pressure piston (8) in a low pressure cylinder (9) and connected to the high pressure piston (6), an intermediate space (11) between the high pressure piston (6) and the low pressure piston (8), a control valve (12) controlling a pressure in the low pressure cylinder (9), and a feeder arrangement of the intensifier section (5) including an input connection (19) connected to the supply port (A1) and a return connection (20) connected to the tank port (B1). Such a pressure amplifier arrangement should have a simple construction. To this end the feeder arrangement (19, 20) comprises throttling means (21).

Abstract: A control system for construction machinery, includes a hydraulic pump, first and second actuators connected to the hydraulic pump through first and second parallel lines respectively, first and second control valves installed in the first and second parallel lines respectively and configured to control operations of the first and second actuators, first and second spool displacement adjusting valves configured to control displacement amounts of the spools of the first and second control valves, and a control valve control portion configured to output the control signal, and configured to limit a maximum allowable value of the manipulation signal for the first actuator to a value selected by the operator and limit a spool displacement amount of the second control valve according to the limited manipulation signal for the first actuator when the manipulation signal for a multiple operation of the first and second actuators is received.

Abstract: A torque converter, including: an impeller supported for rotation around an axis of rotation and including an impeller shell and at least one impeller blade non-rotatably connected to the impeller shell; a cover arranged to receive a rotational torque and including a distal portion including an interior surface in contact with the impeller shell, and an expanded radius portion extending from the distal portion in an axial direction and including an interior surface facing at least partly in a radially inner direction pointing toward the axis of rotation; and a turbine in fluid communication with the impeller and including a turbine shell and at least one turbine blade non-rotatably connected to the turbine shell. The interior surface of the expanded radius portion is located further in a radially outer direction than the interior surface of the distal portion.

Abstract: A hydraulic actuator is disclosed that comprises a first, fixed portion and a second portion movable relative to the first portion. The second portion comprises a hydraulic actuating device for actuating a component, and the actuator further comprises an intermediate member configured to interconnect the first portion with the second portion and permit movement of the second portion relative to the first portion. The intermediate member is configured to convey hydraulic fluid to the hydraulic actuating device of the second portion through a body of the intermediate member.

Abstract: An electrohydraulic system for use under water includes an electrohydraulic actuator and a container having an internal space provided for forming a volume which is enclosed from the environment and which is provided for receiving a hydraulic pressurized fluid. A hydraulic cylinder is provided in the internal space of the container, the inside of which is divided into a first cylinder chamber and a second cylinder chamber by a piston to which a first piston rod and a second piston rod are connected. The two active surfaces of the piston are the same or approximately the same size.