Actuator device; electro-piston

Claim 1

ACTUATING MEANS HAVING AN AXIS, FOR PROVIDING AXIALLY RECIPROCATING MOTION, SAID ACTUATING MEANS HAVING AN AXIS OF RECIPROCAL MOVEMENT AND COMPRISING: A HOUSING; A ROTARY MOTOR MOUNTED TO SAID HOUSING; A DRIVE GEAR JOURNALED TO SAID MOTOR; A DRIVEN GEAR JOURNALED TO SAID HOUSING AND DRIVEN BY SAID DRIVE GEAR; A SPLINE DRIVE SECTIO INTEGRAL WITH THE DRIVEN GEAR AND HAVING AN AXIALLY SPLINE OPENING; A DRIVING NUT; SPLINES AND ON SAID DRIVING NUT ENGAGED IN THE AXIALLY SPLINED OPENING; AN INTERIOR THREAD IN SAID DRIVING NUT; A DRIVING CYLINDER ROTATABLY JOURNALED IN SAID SPLINED OPENING; AN EXTERIOR THREAD ON SAID DRIVING CYLINDER, THE DRIVING NUT BEING THREADED ONTO SAID DRIVING CYLINDER; A DRIVING SCREW RESTRAINED AGAINST ROTATION AND THREADED TO THE DRIVING CYLINDER FOR AXIAL RECIPROCATION AND SPRINGING MEANS TENDING TO HOLD THE DRIVING NUT CENTERED ON THE THREADS ON THE DRIVING CYLINDER, RESISTANCE TO MOVEMENT OF THE ACTUATING SCREW ENABLING THE DRIVING NUT TO OVERRUN THE DRIVING CYLINDER TO STOP CAUSING THE LATTER TO ROTATE AND TO PERMIT REVERSAL OF MOTION UPON REVERSAL OF MOTOR ROTATION.