Patent ID: 7255290

Claim:
Apparatus for injecting fuel into a combustion chamber of an internal combustion engine comprising: a solid magnetostrictive material with a favored direction of magnetostrictive response formed into a shape with ends that are substantially parallel to each other and substantially perpendicular to the favored direction of magnetostrictive response; a control valve element located coaxial to the favored direction of magnetoelastic response of the magnetostrictive material; a solenoid coil located concentric with the magnetostrictive material and coaxial to the favored direction of magnetoelastic response, the solenoid coil adapted to excite the magnetostrictive material into mechanical motion; a magnetic return path circuit in magnetic communication with the solid magnetostrictive material; and a mechanism associated with the magnetostrictive material, the mechanism adapted to subject the magnetostrictive material to a static compressive stress magnitude of no less than fourteen megapascals along the favored direction of magnetostrictive response with an effective stiffness no greater than one-fourth the stiffness of the magnetostrictive element without the magnetostrictive material being subjected to a magnetic field by the mechanism.