SYSTEM AND METHOD FOR PUMP-CONTROLLED CYLINDER CUSHIONING

摘要

A system (10) and method for controlling the movement of an implement (104-108) of an earthmoving machine (100). The system (10) includes a hydraulic actuator (12) adapted to move the implement (104-108). A variable displacement pump (14) is coupled to the actuator (12) for delivering a pressurized fluid to and receiving pressurized fluid from chambers within the actuator (12). A sensor (26) generates an output based on the position of the actuator's piston (22) or piston rod (24), and a controller (28) controls the displacement of the variable displacement pump (14) in response to the output of the sensor (26) by executing an algorithm to reduce the flow rate of the fluid to and from the actuator's chambers and thereby reduce the velocity of the piston (22) as it approaches an end of a piston stroke thereof and prevent the piston (22) from impacting the actuator (12) at the end of the piston stroke.