A system for controlling hydraulic fluid flow within a work vehicle includes a flow control valve fluidly coupled to a fluid supply conduit upstream of a hydraulic actuator such that the flow control valve is configured to control the flow rate of hydraulic fluid to the hydraulic actuator. Furthermore, the system includes a computing system configured to receive an input associated with a selected flow rate of the hydraulic fluid being supplied to the hydraulic actuator. Moreover, the computing system is configured to control an operation of the flow control valve such that flow control valve is at a maximum flow position at which an adjustable orifice defined by the valve has a maximum cross-sectional area. Additionally, the computing system is configured to control an operation of a pump such that the pump supplies the hydraulic fluid to the hydraulic actuator through the adjustable orifice at the selected flow rate.

When hydraulic fluid discharged from a hydraulic actuator is to be recovered for driving a different hydraulic actuator, the recovery frequency is increased to achieve further energy saving. To this end, a pressure increasing circuit 36 is provided in which a communication pressure increasing valve 12 is disposed in a communication passage 26 that connects a bottom side line 23 of and a rod side line 24 a boom cylinder 4. A recovery control valve 11 is controlled such that, when a first operation unit 5 is operated in a boom lowering direction (own weight falling direction of the boom) and a second operation unit 6 is operated simultaneously, only if the pressure at the bottom side of the boom cylinder 4 is higher than the pressure at the arm cylinder side that is a recovery destination of hydraulic fluid, the recovery control valve 11 is opened to recover the flow rate discharged from the bottom side of the boom cylinder 4 to the arm cylinder side.

A hydraulic system for a machine is disclosed. The hydraulic system may have a tank configured to hold a supply of fluid, a pump configured to draw fluid from the tank and pressurize the fluid, a first cylinder operatively connected between a first side of a work tool and an undercarriage of the machine, and a second cylinder operatively connected between a second side of the work tool and the undercarriage of the machine. The hydraulic system may also have a first electro-hydraulic valve associated with the first cylinder and configured to selectively regulate a flow of pressurized fluid to the first cylinder independently of the second cylinder, and a second electro-hydraulic valve associated with the second cylinder and configured to selectively regulate a flow of pressurized fluid to the second cylinder independently of the first cylinder.

A linear actuator system includes a linear actuator and at least one proportional control valve and at least one pump connected to the linear actuator to provide fluid to operate the linear actuator. The at least one pump includes at least one fluid driver having a prime mover and a fluid displacement assembly to be driven by the prime mover such that fluid is transferred from the pump inlet to the pump outlet. The linear actuator system also includes a controller that establishes at least one of a speed and a torque of the at least one prime mover and concurrently establishes an opening of the at least one proportional control valve to adjust at least one of a flow and a pressure in the linear actuator system to an operational set point.

A compensator spool of a load sensing valve device includes a pressure chamber, a compensator throttle portion, a pressure introduction chamber, a pressure introduction port, a maximum load pressure introduction chamber, and a selector valve. A groove is formed around the pressure introduction port, and a groove moves relatively between a passage communicating with an actuator to reduce an opening area of the pressure introduction port when the compensator spool moves.

A first flow path area at a position where one of multiple openings of a sleeve and one of multiple grooves of a spool overlap with each other is different in size from a second flow path area at a position where another one of the openings of the sleeve and another one of the grooves of the spool overlap with each other. The one opening and the one groove form a flow path for connecting one of one pressure chamber and the other pressure chamber to a fluid supply source, due to displacement of the spool. The other opening and the other groove form a flow path for connecting another one of the other pressure chamber and the one pressure chamber to a fluid discharge port, due to the displacement of the spool.

A device for riveting and a hydropneumatic device for pressure transmission, including a working piston and a transmitter piston in the form of a double-acting cylinder for transmitting pressure to the working piston, wherein a working stroke of the working piston in a working direction includes a first stroke and a subsequent second stroke, wherein the first stroke is controlled by means of pneumatic pressure acting on the working piston and the second stroke is controlled by means of pneumatic pressure acting on the transmitter piston, and wherein hydraulic fluid is displaced by the transmitter piston and the displaced hydraulic fluid effects the second stroke of the working piston. Regulation means having an actuating device are provided for regulating the pneumatic pressure on both sides of the double-acting cylinder of the transmitter piston such that the second stroke of the working piston is predefined by way of the regulation.

The present disclosure relates to a hydraulic control circuit for crane slewing gear having directional valves arranged in work lines and controllable separately for the inflow and outflow to the hydraulic motor for the carrying out of a rotational movement of the slewing gear, wherein an inflow valve serves the control of the oil inflow from a hydraulic pump via the work line to the hydraulic motor and an outflow valve is provided via which the hydraulic motor can be relieved to the tank, wherein the work lines are each connected via at least one check valve to a common inlet of the outflow valve to relieve the hydraulic motor independently of the direction of rotation of the slewing gear via an outflow valve into the tank.

Working system for an application of force onto a workpiece, with a pneumatic actuator having an actuator housing designed to be fixed to a manipulator and a moveable element designed to couple an end effector and movably received on the actuator housing, and with a controller having a valve arrangement for a compressed air supply to the pneumatic actuator, has a position sensor system for determining a spatial position of the pneumatic actuator and for providing position-dependent electrical position sensor signals, and a processing system for processing the position sensor signals and for providing control signals to the valve arrangement, the processing system being designed for controlling a pneumatic supply to the pneumatic actuator as a function of the position sensor signals.

A system has a hydraulic circuit configured to control a position of an attachment of the system and a control system configured to perform operations that include receiving an input indicative of a center of gravity of the attachment and controlling a flow rate of fluid directed through the hydraulic circuit based on the center of gravity.