Compensator assembly having a pressure responsive valve for a solid state actuator of a fuel injector

摘要

A fuel injector comprises a body having a longitudinal axis, a length-changing solid state actuator that has first and second ends, a closure member coupled to the first end of the solid state actuator, and a compensator assembly coupled the second end of the solid state actuator. The solid state actuator includes a plurality of solid state elements along the axis between the first and second ends. The closure member is movable between a first configuration permitting fuel injection and a second configuration preventing fuel injection. And the compensator assembly axially positions the solid state actuator with respect to the body in response to temperature variation. The compensator assembly utilizes a configuration of at least one spring disposed between two pistons so as to reduce the use of elastomer seals to thereby reduce a slip stick effect. Also, a method of compensating for thermal expansion or contraction of the fuel injector comprises providing fuel from a fuel supply to the fuel injector; and adjusting the solid state actuator with respect to the body in response to temperature variation.