Sound movie projector

Abstract

Abstract A PROJECTOR FOR SHOWING SOUND MOVIES STORED IN A CARTRIDGE ON SILENT MOTION PICTURE FILM AND MAGNETIC RECORDING TAPE IS DISCLOSED. THE SILENT MOTION PICTURE FILM AND THE MAGNETIC RECORDING TAPE ARE WOUND INTERLEAVED ON A REEL. THE TAPE AND THE FILM ON THE REEL EACH FOLLOW A PATH THROUGH THE CASSETTE IN WHICH PORTIONS THEREOF COINCIDE AND PORTIONS THEREOF SEPARATE TO ALLOW FOR PROJECTION OF THE FILM AND PLAYBACK OR RECORDING ON THE TAPE. A GUIDE ROLLER MECHANISM FOR THE TAPE IS ALSO DISCLOSED WHICH INCLUDES A MECHANISM FOR MAINTAINING A TENSION ON THE TAPE TO TAKE UP ANY SLACK WHICH DEVELOPES IN THE TAPE AND ALSO HELPS IN SMOOTHING OUT THE INSTANTANEOUS TAPE VELOCITY AS IT TRAVELLS ALONG ITS PATH. A HALF SILVERED MIRROR IS MOUNTED IN THE CASSETTE AT AN ANGLE WITH RESPECT TO A LINE NORMAL TO THE PLANE IN WHICH THE FILM TRAVELS ALONG ITS PATH. A CIRCUIT IS ALSO DISCLOSED FOR DRIVING A MOTOR IN A CONSTANT CURRENT MODE TO PRODUCE A CONSTANT TORQUE ON THE ENDS OF THE FILM AND THE TAPE AS A PAIR OF SHUTTER FINGERS ADVANCE THE FILM. IN THIS WAY, MOTION IS IMPARTED TO THE ENDS OF THE TAPE THEREBY MOVING THE TAPE AT THE SAME AVERAGE VELOCITY AS THE FILM. INTERTIAL MEANS ARE ASSOCIATED WITH THE TAPE TO SMOOTH OUT THE INTERMITTENT MOTION CAUSED BY THE SHUTTER FINGERS.

Inventors

• 👤 Alan Chernotsky
• 👤 Richard Satz

Bibliographic Details