摘要:
A hoist positioning system includes an accelerometer attached to a hoist, a control unit for processing signals from the accelerometer and comparing the processed signals with reference data to determine a position of the hoist, a drive system for moving the hoist up and down, and a relay that is switched ON and OFF by a control signal from the control unit. When the relay is switched ON, power is supplied to the drive system from a high-voltage power source and the hoist is driven up or down. When the relay is switched OFF, power from the high-voltage power source to the drive system is cut off and the hoist stops moving up or down.
摘要:
A valve has a valve body including a main chamber having a first port and a second port, and a main poppet disposed within the main chamber. The main poppet includes a first surface forming a control chamber within the main chamber. The valve has a first passage communicating the control chamber with the first port, and a second passage communicating the control chamber with the second port. The valve also includes a pilot valve having a pilot poppet for controlling fluid flow from the control chamber to the first port through a third passage, and to the second port through a fourth passage, respectively. The valve may further have a feedback spring coupled between the main poppet and the pilot poppet to provide a force relative to a distance between the main poppet and the pilot poppet.
摘要:
A hydraulic system for a work machine is disclosed. The hydraulic system has a source of pressurized fluid and a fluid actuator with a first chamber and a second chamber. The hydraulic system also has a first valve configured to selectively fluidly communicate the source with the first chamber and a second valve configured to selectively fluidly communicate the source with the second chamber. The hydraulic system further has a proportional pressure compensating valve configured to control a pressure of a fluid directed between the source and the first and second valves.
摘要:
A hydraulic system for a work machine is disclosed. The hydraulic system has a source of pressurized fluid and a fluid actuator with a first chamber and a second chamber. The hydraulic system also has a first valve configured to selectively fluidly communicate the source with the first chamber and a second valve configured to selectively fluidly communicate the source with the second chamber. The hydraulic system further has a proportional pressure compensating valve configured to control a pressure of a fluid directed between the source and the first and second valves.
摘要:
A fluid flow-control apparatus for a swing system of a work machine. The system includes a source of variable pressurized fluid, directional flow device coupled to said source of pressurized fluid, said directional flow device having a directional flow member, a flow-compensation device coupled to said directional flow device, a fluid flow-biasing device coupled to said flow-compensation device, and a plurality of motors coupled to said directional flow device.
摘要:
A hydraulic control system for a machine is disclosed. The hydraulic control system may have a pump configured to pressurize fluid, and a motor driven by a flow of pressurized fluid from the pump. The hydraulic control system may also have a first accumulator configured to receive pressurized fluid discharged from the motor and to selectively supply pressurized fluid to the motor, and a second accumulator configured to receive pressurized fluid discharged from the motor and selectively supply pressurized fluid to the motor.
摘要:
A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a pump, a tank, and an actuator. The hydraulic control system may also have at least a first valve configured to control fluid flow between the pump, the tank, a first chamber of the actuator, and a second chamber of the actuator; a second valve fluidly disposed between the second chamber and the tank; and a third valve fluidly disposed between the first and second chambers. The hydraulic control system may further have a controller configured to selectively cause the second valve to block fluid flow from the second chamber of the actuator to the tank, and to selectively cause the third valve to fluidly communicate the first and second chambers of the actuator when the second valve blocks fluid flow from the second chamber of the actuator to the tank.
摘要:
A hydraulic control system includes an implement movable to perform an excavation cycle having a plurality of segments, a variable displacement motor configured to swing the implement at a desired speed during the excavation cycle, and a pump configured to pressurize fluid directed to drive the motor. The system further includes an accumulator configured to selectively receive fluid discharged from the motor via a charge valve, and to discharge fluid to the motor via a discharge valve. The system includes a selector valve fluidly connected to the charge valve and the discharge valve. The system also includes a controller configured to vary displacement of the motor, resulting in the desired speed.
摘要:
An energy storage system is disclosed for use in a hydraulic system for moving a structural member such as a boom assembly. The system features at least one work cylinder and an additional energy storage cylinder that assists in raising and lowering functions by storing and withdrawing pressurized fluid from an accumulator. The pressurized fluid in the accumulator may be used for raising operations as well as digging and tamping operations. Further, the energy recovery features may be selectively disconnected during either a raising or lowering operation.
摘要:
A hydraulic control system is disclosed for use with a machine. The hydraulic control system may have a pump, a tank, and an actuator. The hydraulic control system may also have at least a first valve configured to control fluid flow between the pump, the tank, a first chamber of the actuator, and a second chamber of the actuator; a second valve fluidly disposed between the second chamber and the tank; and a third valve fluidly disposed between the first and second chambers. The hydraulic control system may further have a controller configured to selectively cause the second valve to block fluid flow from the second chamber of the actuator to the tank, and to selectively cause the third valve to fluidly communicate the first and second chambers of the actuator when the second valve blocks fluid flow from the second chamber of the actuator to the tank.