Pull down arrangement for cinematographic apparatus

Claim 1

IN A MOTION PICTURE APPARATUS, IN COMBINATION, A FLIM GATE; GUIDE MEANS LOCATED IN ADVANCE OF AND SUBSEQUENT TO SAID FILM GATE FOR GUIDING FILM TO AND FROM SAID FILM GATE; FIRST CLAMPING MEANS LOCATED ADJACENT SAID GUIDE MEANS AND IN ADVANCE OF SAID FILM GATE AND SECOND CLAMPING MEANS LOCATED AT SAID FILM GATE, EACH CLAMPING MEANS BEING MOVABLE BETWEEN A CLAMPING POSITION PREVENTING MOVEMENT OF THE FILM AND A NON-CLAMPING POSITION RELEASING THE FILM FOR MOVEMENT; PNEUMATIC MEANS LOCATED ADJACENT SAID GUIDE MEANS SUBSEQUENT TO SAID FILM GATE FOR ADVANCING FILM PAST SAID FILM GATE WHEN SAID SECOND CLAMPING MEANS IS IN SAID NON-CLAMPING POSITION THEREOF; ACTUATING MEANS COOPERATING WITH SAID FIRST AND SECOND CLAMPING MEANS FOR ALTERNATELY ACTUATING THE LATTER TO PLACE SAID SECOND CLAMPING MEANS IN SAID NONCLAMPING POSITION WHILE SAID FIRST CLAMPING MEANS IS IN ITS CLAMPING POSITION AND TO PLACE SAID SECOND CLAMPING MEANS IN SAID CLAMPING POSITION WHILE SAID FIRT CLAMPING MEANS IS IN ITS NON-CLAMPING POSITION; AND CLAW MEANS LOCATED ADJACENT SAID GUIDE MEANS IN ADVANCE OF SAID FIRST CLAMPING MEANS FOR ADVANCING THE FILM IN A STEPWISE MANNER TOWARD SAID GATE WHILE SAID FIRST CLAMPING MEANS IN IN SAID NON-CLAMPING POSITION THEREOF, SAID CLAW MEANS INCLUDING AN ELONGATED CLAW MEMBER HAVING A TOOTHED END ADAPTED TO ENTER INTO A FILM PERFORATION, A ROTARY CRANK PIVOTALLY CONNECTED TO AN END PORTION OF SAID CLAW MEMBER DISTANT FROM SAID TOOTHED END THEREOF CONTINUOUSLY MOVING SAID END PORTION OF SAID CLAW MEMBER ALONG A CIRCULAR PATH, AND A SWING LEVER PIVOTALLY CONNECTED TO SAID CLAW MEMBER BETWEEN SAID CRANK AND TOOTHED END THEREOF AND HAVING A STATIONARY PIVOT AXIS DISTANT FROM ITS CONNECTION TO SAID CLAW MEMBER, SAID ROTARY CRANK AND SWING LEVER COOPERATING TO PROVIDE SAID TOOTHED END OF SAID CLAW MEMBER WITH AN ENDLESS PATH OF MOVEMENT CONFORMING SUBSTANTIALLY TO THE CONFIGURATION OF AN ISOSCELES TRIANGLE WHOSE BASE IS NEAREST TO SAID FIRST CLAMPING MEANS AND WHOSE APEX IS DISTANT FROM SAID FIRST CLAMPING MEANS SO THAT THE TOOTHED END OF SAID CLAW MEMBER IS RETRACTED AWAY FROM THE FILM WHILE MOVING ALONG SAID BASE AND ENGAGES THE FILM WHEN LOCATED AT SAID APEX.