Motion picture sound projector

Claim 1

A MOTION PICTURE SOUND PROJECTOR FOR USE WITH MOTION PICTURE FILM HAVING A SOUND STRIPE PORTION EXTENDING ALONG ONE SIDE THEREOF COMPRISING A FIRST DRIVE SPROCKET, A FIXED FILM GUIDE ADJACENT SAID FIRST DRIVE SPROCKET DEFINING A FILM PASSAGE ENTRANCE TO SAID FIRST DRIVE SPROCKET, A MOVABLE LOOP FORMING MEMBER HAVING A CONCAVE DOWNWARDLY FILM GUIDING PORTION DISPOSED REARWARDLY OF SAID FIRST DRIVE SPROCKET, SAID LOOP FORMING MEMBER BEING MOVABLE BETWEEN A LOWER THREADING POSITION AND AN UPPER RUNNING POSITION, A FILM GATE, A PROJECTOR LAMP DISPOSED BEHIND SAID FILM GATE, AN APERTURE IN SAID FILM GATE FOR PASSING LIGHT FROM SAID PROJECTOR LAMP THROUGH SAID FILM, A SECOND MOVABLE LOOP FORMING CHAMBER HAVING A CONCAVE UPWARDLY FILM GUIDING PORTION, SAID SECOND LOOP FORMING MEMBER BEING MOVABLE BETWEEN A THREADING POSITION AND A LOWER RUNNING POSITION AND EXTENDING FROM THE END OF SAID FILM GATE IN A GENERALLY REARWARD DIRECTION, A SECOND DRIVE SPROCKET ADJACENT THER TERMINAL PORTION OF SAID SECOND LOOP FORMING MEMBER, A SOUND DRUM MOUNTED COAXIALLY WITH SAID SECOND DRIVE SPROCKET FOR ROTATION INDEPENDENTLY THEREOF, SAID SOUND DRUM INCLUDING A CIRCUMFERENTIAL SURFACE FOR SUPPORTING THE SOUND STRIPE PORTION OF THE FILM ONLY, AN OUTPUT FILM GUIDE STRUCTURE DISPOSED REARWARDLY OF SAID SECOND DRIVE SPROCKET TO RECEIVE FILM THEREFROM FOR GUIDING TO THE TAKEUP REEL, A SOUND HEAD DISPOSED IMMEDIATELY ADJACENT SAID SOUND DRUM INCLUDING A POLE PIECE ADAPTED TO BE POSITIONED IN ENGAGEMENT WITH THE SOUND STRIPE OF FILM SUPPORTED ON SAID SOUND DRUM, MEANS TO LIFT SAID SOUND HEAD AND TO PLACE SAID FIRST AND SECOND LOOP FORMING MEMBERS IN THREADING POSITION SO THAT FILM PLACED IN ENGAGEMENT WITH THE TEETH OF SAID FIRST DRIVE SPROCKET IS AUTOMATICALLY FED BY SAID DRIVE SPROCKET THROUGH THE THREADING PATH AND ACROSS SAID SECOND DRIVE SPROCKET AND SOUND DRUM SOLELY AS URGED BY SAID DRIVE SPROCKETS IN A SELFTHREADING OPERATION, FILM SENSOR MEANS DISPOSED IN SAID OUTPUT FILM GUIDE STRUCTURE, AND MEANS RESPONSIVE TO THE SENSING OF THE FILM IN SAID OUTPUT FILM GUIDE STRUCTURE BY SAID FILM SENSOR MEANS TO LOWER SAID SOUND HEAD INTO ENGAGEMENT WITH THE SOUND STRIPE PORTION OF SAID SOUND DRUM.