Motor operating mechanism for use with an electric circuit breaker

Claim 1

AN ELECTRIC MOTOR OPERATING MECHANISM FOR USE WITH AN ELECTRIC SWITCHING DEVICE HAVING AN OSCILLATABLE HANDLE, COMPRISING: (A) A RIGID SUPPORT, (B) AN ELECTRIC MOTOR MOUNTED ON SAID SUPPORT FOR LIMITED SLIDING MOVEMENT RELATIVE TO SAID SUPPORT, (C) BIASING MEANS BIASING SAID ELECTRIC MOTOR AGAINST SLIDING MOVEMENT IN A FIRST DIRECTION, (D) SAID ELECTRIC MOTOR HAVING AN OPERATING SHAFT PROJECTING FROM ONE END THEREOF, (E) AN ELONGATED THREADED SHAFT IN AXIAL ALIGNMENT WITH AND HAVING ONE END CONNECTED TO AND SUPPORTED BY SAID OPERATING SHAFT, (F) A TRAVELLING NUT ASSEMBLY CARRIED BY SAID THREADED SHAFT, (G) INTERENGAGING MEANS CARRIED BY SAID TRAVELLING NUT ASSEMBLY AND SAID HOUSING FOR SUPPORTING AND GUIDING SAID TRAVELLING NUT ASSEMBLY FOR RECTILINEAR RECIPROCAL MOVEMENT ALONG SAID SHAFT, (H) SAID ELECTRIC MOTOR AND SAID ELONGATED THREADED SHAFT BEING MOVABLE A SMALL AMOUNT IN A DIRECTION PARALLEL TO THE AXIS OF SAID THREADED SHAFT UPON THE OBSTRUCTION OF MOVEMENT OF SAID TRAVELING NUT, TO CAUSE SLIDING MOVEMENT OF SAID MOTOR AND SAID SHAFT AGAINST THE BIAS OF SAID BIASING SPRINGS, (I) A STOP CARRIED BY SAID THREADED SHAFT, (J) SAID TRAVELLING NUT ASSEMBLY BEING CAPABLE OF ASSUMING AN OVERRUNNING CONDITION UPON ENGAGEMENT THEREOF WITH SAID STOP CARRIED BY SAID SHAFT, (K) SAID STOP BEING POSITIONED SO AS TO BE ENGAGED BY SAID TRAVELLING NUT SHORTLY AFTER SAID MOTOR AND SAID SHAFT COMMENCE SAID SLIDING MOVEMENT, WHEREBY TO RESTRICT THE STRESSING OF SAID BIASING MEANS TO A PREDETERMINED AMOUNT.