Abstract:
A hydraulic energy recovery device for a hydraulic system is disclosed. The hydraulic energy recovery device has a first impeller configured to receive a flow of pressurized liquid, and a second impeller configured to pressurize a flow of liquid. The hydraulic energy recovery device also has a common shaft connecting the first and second impellers.
Abstract:
A hydraulic system for a work machine is provided. The hydraulic regeneration system has a tank, a primary source, a first actuator, an accumulator, and a first valve mechanism. The tank is configured to hold a supply of fluid. The primary source is configured to pressurize the fluid and has a suction inlet and a discharge outlet. The first actuator is configured to receive pressurized fluid from the discharge outlet of the primary source. The accumulator is in fluid communication with the tank, the suction inlet of the primary source, and the first actuator. The first valve mechanism is disposed between the suction inlet of the primary source and the accumulator, and is movable between a first position at which fluid returning from the first actuator is directed to the suction inlet of the primary source, and a second position at which fluid returning from the first actuator is directed to only the accumulator.
Abstract:
A metering valve for a work machine hydraulic system is disclosed. The metering valve has an inlet and an outlet, a main poppet, and a solenoid-operated pilot element. The main poppet is movable to pass fluid from the inlet to the outlet, and to block fluid from the inlet to the outlet. The solenoid-operated pilot element is movable between a first position at which pressurized fluid from the inlet pressurizes a control chamber in communication with a control end of the main poppet to urge the main poppet toward the flow-blocking position, and a second position at which the control chamber is communicated with a drain to move the main poppet toward the flow-passing position. The metering valve also has a relief valve element configured to drain pressurized fluid from the control chamber to move the main poppet toward the flow-passing position in response to a pressure at the inlet exceeding a predetermined pressure.
Abstract:
A metering valve for a work machine hydraulic system is disclosed. The metering valve has a valve body with an inlet and an outlet. The metering valve also has a main poppet disposed within the valve body between the inlet and the outlet. The main poppet has a nose end and a chamber end, and is movable between a flow-passing position at which fluid flows from the inlet to the outlet, and a flow-blocking position at which fluid flow between the inlet and outlet is blocked. The metering valve also has a pilot element movable to selectively communicate the chamber end of the main poppet with a drain, thereby affecting movement of the main poppet between the flow-passing and flow-blocking positions. The metering valve further has a solenoid mechanism operable to move the pilot element. The position of the pilot element is affected by a fluid pressure at the inlet.
Abstract:
An articulated work machine is steered via left and right hydraulic cylinders that swivel a front portion of a work machine relative to a back portion about a vertical articulation axis. When a low force turn is being performed, high pressure is supplied to only one of the left and right hydraulic cylinders. When a high force turn is performed, high pressure is supplied to one of the left and right hydraulic cylinders, and pressurized hydraulic fluid is also supplied to the other of the left and right hydraulic cylinders in proportion to the torque required for the turn. This strategy allows for excess pressurized fluid, which is not used for the steering purpose, to be utilized by hydraulic implements of the work machine to increase performance capabilities while the machine is being steered in low force mode under light steering load.