METHOD OF CONTROLLING VELOCITY OF A HYDRAULIC ACTUATOR IN OVER-CENTER LINKAGE SYSTEMS

摘要

An electro-hydraulic actuation system includes a regeneration valve in fluid communication with a first fluid chamber and a second fluid chamber of a hydraulic actuator, and a dump valve is in fluid communication with the second fluid chamber and a fluid reservoir. A pump provides a flow of fluid to the first and second fluid chambers, a displacement of the pump controlling a velocity of the actuator during motion in the retraction and extension directions. An electric motor drives the pump, and a controller controls a state of the regeneration valve and the dump valve. At least one feedback device senses a system condition and provides a respective feedback signal indicative of the sensed system condition to the controller, the controller responsive to the feedback signal to determine an occurrence of an over-center load condition and control a state of the regeneration valve and the dump valve in response to the occurrence to maintain the velocity of the actuator.