Patent ID: 6619186
Filing Date: 2003-09-16
Classification: F02M

Abstract:
An actuator having a variable length extending between an energy receiving end and an energy transmitting end, said actuator comprising:a body defining a first bore; an actuator piston disposed in said first bore and defining a second bore, said actuator piston movable relative to said body to define a variable volume first hydraulic chamber between said body and said actuator piston; and a servo piston disposed in said second bore and movable relative to said actuator piston to define a second variable volume hydraulic chamber between said actuator piston and said servo piston; wherein the length of said actuator is dependent upon the volume of said first hydraulic chamber, movement of said servo piston relative to said actuator piston controls delivery of a first hydraulic pressure to said first hydraulic chamber and movement of said servo piston is controlled by delivery of a second hydraulic pressure to said second hydraulic chamber, said second hydraulic pressure being modulated from said first hydraulic pressure.