Rotary actuator mechanism

Claim 1

IN A ROTARY ACTUATOR HAVING A DRIVE MOTOR UNIT PROVIDING POWER FOR A ROTARY OUTPUT SHAFT ADAPTED TO BE CONNECTED TO AN ACTUATED DEVICE, A MANUAL OVERRIDE MECHANISM COMPRISING: AN OUTPUT SHAFT; A MEMBER ROTATABLY MOUNTED ON THE OUTPUT SHAFT AND DRIVABLE BY A SHAFT OF THE MOTOR UNIT, SAID MEMBER INCLUDING AN ANNULAR FLANGE PROVIDED WITH AN INTERNAL CIRCUMFERENTIAL SERIES OF SERRATIONS COAXIAL WITH THE OUTPUT SHAFT; MEANS FIXED ON THE OUTPUT SHAFT WITHIN THE ANNULAR FLANGE FORMING A SPACED PAIR OF PAWL SEATS EQUI-SPACED RADIALLY FROM THE SHAFT; A PAIR OF PAWLS PIVOTALLY SEATED IN RESPECTIVE SEATS EXTENDING TOWARD THE FLANGE; MEANS NORMALLY BIASING THE FREE ENDS OF THE PAWLS INTO CONTACT WITH THE SERRATIONS; THE PAWLS BEING ADAPTED UNDER THE BIAS OF THE LAST SAID MEANS FOR A DRIVEN ENGAGEMENT WITH SAID SERRATIONS, ONE UPON ROTATION OF SAID MEMBER IN ONE DIRECTION AND THE OTHER UPON ROTATION IN THE OTHER DIRECTION; A MANUALLY ROTATABLE CONTROL MEMBER MOUNTED FOR ROTATION COAXIALLY OF SAID OUTPUT SHAFT; COOPERATING MEANS ON SAID CONTROL MEMBER AND ON THE RESPECTIVE PAWLS ADAPTED TO RELEASE POSITIVELY UPON MANUAL ROTATION OF THE CONTROL MEMBER IN OPPOSITE DIRECTIONS A RESPECTIVE ONE OF SAID PAWLS WHICH WOULD TEND TO DRIVE THE FIRST SAID MEMBER; AND LOST MOTION CONNECTION MEANS BETWEEN SAID OUTPUT SHAFT AND CONTROL MEMBER.