Patent ID: 6715695
Filing Date: 2004-04-06
Classification: F02M

Abstract:
A method of compensating for distortion of a fuel injector, the fuel injector including a housing having a first housing end and a second housing end extending along a longitudinal axis, a length-changing solid state actuator disposed along the longitudinal axis, a closure member coupled to the solid state actuator, and a compensator assembly that moves the length-changing actuator with respect to the housing in response to temperature changes, the compensator assembly including a body having a first body end and a second body end extending along a longitudinal axis, the body having a body inner surface facing the longitudinal axis, a spacer disposed between the first piston and the second piston in the body, the spacer having a first spacer end and a second spacer end in fluid communication with one another, the first spacer end being disposed in a confronting arrangement to one of the first face and second face so as to define a first fluid reservoir within the body, the second spacer end being disposed in a confronting arrangement to the other of the first face and the second face so as to define a second fluid reservoir within the body, and a valve disposed in one of the first and second reservoir, the valve being responsive to one of a first fluid pressure in the first fluid reservoir and a second fluid pressure in the second reservoir so as to permit fluid flow, the method comprising:containing a predetermined amount of hydraulic fluid in the first and second fluid reservoirs; pressurizing the hydraulic fluid in at least one of the first and second fluid reservoirs so as to displace the first piston; and preventing communication of hydraulic fluid between the first and second fluid reservoirs during activation of the length changing actuator so as to capture a volume of hydraulic fluid in one of the first and second fluid reservoirs.