Automatic rewinding mechanism for film or the like

Claim 1

IN A MECHANISM FOR AUTOMATICALLY REWINDING A WEB AFTER IT HAS BEEN TRANSPORTED IN ONE DIRECTION BY INTERMITTENT FILM PULL-DOWN MEANS THROUGH A MOTION PICTURE PROJECTOR OR THE LIKE HAVING SUPPLY AND TAKE-UP REELS, THE COMBINATION COMPRISING: AN OPERATING STATION FOR SAID WEB; DRIVE MEANS FOR DRIVING SAID FILM PULL-DOWN MEANS FOR TRANSPORTING SAID WEB THROUGH SAID OPERATING STATION IN ONE DIRECTION, AND FOR SELECTIVELY DRIVING ONE OF SAID SUPPLY AND TAKE-UP REELS; SHIFTING MEANS MOVABLE BETWEEN A NORMAL FORWARD POSITION IN WHICH IT COUPLES SAID DRIVE MEANS TO SAID TAKE-UP REEL TO WIND UP SAID WEB THEREON AS SAID WEB IS TRANSPORTED THROUGH SAID OPERATING STATION IN SAID ONE DIRECTION, AND A REVERSE POSITION IN WHICH IT COUPLES SAID DRIVE MEANS TO SAID SUPPLY REEL FOR REWINDING SAID WEB THEREON, AND CONTROL MEANS FOR MOVING SAID SHIFTING MEANS BETWEEN ITS FORWARD AND REVERSE POSITIONS, SAID CONTROL MEANS INCLUDING A SPRING, AND A LATCH FOR RELEASABLY HOLDING SAID SHIFTING MEANS IN ITS NORMAL FORWARD POSITION AGAINST THE BIAS OF SAID SPRING, AND IN RESPONSE TO SAID WEB AFTER IT HAS COMPLETED ITS TRAVEL IN SAID ONE DIRECTION FOR RELEASING SAID SHIFTING MEANS FOR MOVEMENT BY SAID CONTROL MEANS TO ITS REVERSE POSITION FOR AUTOMATICALLY REWINDING SAID WEB ONTO SAID SUPPLY REEL.