Film advance mechanism for motion picture apparatus
OwnerDonald L. Holst JR.inventor
Life of this patent
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Abstract
A motion picture apparatus and method for intermittently advancing motion picture film by forced air. The film is initially placed into successive loops formed by closure of a rotary air valve. The loops and thus the film are advanced through the projector or camera pathway by a forced air blower which propels the successive loops through a projection pathway by opening of the rotary air valve. The film loop is metered by timing the opening and closing of the rotary air valve with the opening and closing of the shutter of the motion picture apparatus.
Claims7
A film advance mechanism comprising
- film input mechanism for moving film along a path past an aperture;
- film take-up mechanism taking up film having passed the aperture;
- first and second rows of register pins arranged in linear fashion along opposite edges of the path between the film input mechanism and the film take-up mechanism for engaging perforated openings on the film;
- and
- a rotary air valve adjacent the film input mechanism for advancing the film by air.
A method for advancing film in a motion picture device such as a camera or projector, comprising:
- providing a take-off spool to supply film;
- forming a loop in the film at an entrance to an aperture position by closure of a rotary air valve.
- blowing the loop across the aperture position and toward a film take-up spool by opening the rotary air valve;
- and
- releasing successive loops of film to be blown across the aperture position by timing the opening and closing of the air valve relative to opening and closing a shutter.
Dependencies are inferred from the claim text.