Patent ID: 8025130

Claim:
A power device comprising: a motor outputting a driving torque in a first and a second rotary direction; a drive shaft; and a cam mechanism including first and second cam members, said first cam member in driven engagement with said motor and including a circumferentially disposed ramped surface increasing in axial extent along the circumferential extent thereof, said ramped surface having a stop member at a first end thereof, said second cam member axially and rotatably fixed with said drive shaft and rotationally driven by said first cam member in the first and second rotary directions, said second cam member including an axially extending protrusion disposed about a circumference thereof, said protrusion slidably engaged with said ramped surface, rotation of said first cam member in the first rotary direction axially translating said drive shaft in a first axial direction and rotating said drive shaft in the first rotary direction and rotation of said first cam member in the second rotary direction translating said drive shaft in a second axial direction opposite the first axial direction and rotating said drive shaft in the second rotary direction; wherein said second cam member includes a recess receiving said drive shaft therein, said recess including a flat thereon, said drive shaft including a flat thereon generally abutting said flat on said recess.