Patent ID: 6912750
Filing Date: 2005-07-05
Classification: B65G

Abstract:
1. A hydraulically operated dock leveler for forming a bridge between a floor of a loading dock and a truck bed, said dock leveler comprising: a ramp assembly hinged at its rear edge to a supporting frame and movable through a range of raised and lowered inclined positions with a lip assembly hinged to the forward edge of the ramp assembly movable from a downward pendant position to an outwardly extended position; a single hydraulic cylinder means connected to the supporting frame structure and to an actuator mechanism that when extending provides a force to lift said ramp assembly and extend said lip assembly; said actuator mechanism connected to and rotational around the forward hinge to affect both the lifting of the said ramp assembly and extending of the said lip assembly thus providing two modes of operation, said actuator mechanism comprising an extension crank to apply direct ramp lifting and lip extending-mode positions, an actuator crank to initiate the lip extension mode when the said ramp assembly is rising near its upper inclined position, a link from said actuator mechanism to the supporting frame structure to initiate the lip extension, and a spring mechanism to retract the said hydraulic cylinder and said actuator assembly when hydraulic fluid pressure is not present; and a motor pump unit to provide fluid under pressure to extend the said hydraulic cylinder and to receive fluid when the cylinder retracts.