Patent ID: 7584692

Claim:
An actuator comprising: (a) a piston at least partially disposed within a cavity, said piston displaceable axially and rotationally inhibited; (b) a first feed conduit for directing a fluid to a first end of said cavity, said fluid capable of exerting force on said piston in a first axial direction, thereby displacing said piston in said first axial direction; (c) a first shaft having helical spline teeth extending from an exterior surface thereof, said first shaft displaceable in said first axial direction when said piston is displaced in said first axial direction; and (d) a second tubular shaft having helical spline teeth extending from an interior surface thereof, said second shaft interiorly-extending helical spline teeth engageable with said first shaft externally-extending helical spline teeth, whereby upon displacement of said first shaft in said first axial direction, said first shaft is urged to rotate in a first rotational direction.