Motion picture film tensioning device

Claim 1

A FILM TENSION REGULATING DEVICE ADAPTED TO VARY THE TENSION OF FILM PASSING FROM A MOTION PICTURE PROJECTOR TO A TAKE-UP REEL ADJACENT THERETO, COMPRISING A TENSION SENSING ARM, RESILIENT REFERENCE MEANS ATTACHED TO SAID ARM, SAID ARM BEING MOVABLE AGAINST SAID RESILIENT REFERENCE MEANS UPON INCREASING TENSION OF SAID FILM, A SECOND ARM MOVABLY AND INDEPENDENTLY CONNECTED WITH RESPECT TO SAID TENSION SENSING ARM, SAID SECOND ARM BEING SPRING BIASED TOWARD SAID TENSION SENSING ARM, STOP MEANS ON SAID TENSION ARM FOR CONTACTING SAID SECOND ARM AFTER A PREDETERMINED MOVEMENT OF SAID TENSION ARM IN RESPONSE TO INCREASING FILM TENSION, SAID TENSION ARM THEREAFTER MOVING SAID SECOND ARM IN RESPONSE TO INCREASING FILM TENSION ABOVE A MINIMUM OPTIMUM VALUE, STOP MEANS LIMITING MOVEMENT OF SAID SECOND ARM TOWARD SAID TENSION ARM, AND ELECTRIC DRIVE MOTOR, MEANS CONNECTING SAID DRIVE MOTOR AND REEL FOR CAUSING SAID REEL TO TAKE-UP FILM FROM THE PROJECTOR, A MOTOR CIRCUIT, VARIABLE RESISTANCE