MOTION-PICTURE CAMERA AND THE LIKE

• US 3,637,298 A
• Filed: 08/11/1969
• Issued: 01/25/1972
• Est. Priority Date: 08/11/1969
• Status: Expired due to Term

• Current Assignee: Ernest M. Whitley
• Original Assignee: Ernest M. Whitley
• Inventors: Whitley, Ernest M.
• Primary Examiner(s): Prince, Louis R.
• Assistant Examiner(s): Shoon, Frederick
• Application Number:
  US04/848,961
• Time in Patent Office: 897 Days
• Field of Search: 352/221,227,84,72,78
• US Class Current: 352/72
• CPC Class Codes: G03B 17/26 Holders for containing light sensitive material and adapted to be inserted within the camera holders for X-ray films G03B42/04
• CPC Class Codes: G03B 19/18 Motion-picture cameras with non-intermittently running film G03B41/02

Abstract

A motion-picture camera adapted for use on aircraft or the like where extreme forces are likely to occur, and in which a rapid exchange mechanism is effected by a two-piece construction with the film gate and associated film drive mechanism decouplable from the main body of the camera, and in which the film drive mechanism operates with an eccentric drive for providing stop and go motion through a zero clearance gate, the improvements consisting of an improved adjustable zero clearance gate, guides for handling the film through the film gate, and improvements in the two-piece construction including a novel latch mechanism capable of providing a rapid exchange, yet which also positively provides for accurate placement of the film gate in exact focus position.

Claims

1. In a high-speed movie camera adapted to move a strip of film in stop and go motion through a film gate formed for holding film positively stationary in exposure position when the camera is subjected to relatively severe conditions of vibration and change of velocity, in combination, a zero clearance film gate, a stationary registration pin mounted in said film gate, and a film-driving means;

said film gate being constructed with guide means at the film gate having guide elements between which the film passes and formed for establishing substantially zero clearance by providing a distance between said guide elements substantially exactly the same as the thickness of the film going through the film gate, said guide elements being relatively adjustable whereby film strips of different thicknesses may be accommodated in said zero clearance fashion, and means for fixedly securing said guide elements in the desired adjusted position.

2. The high-speed movie camera defined in claim 1, in which said guide elements comprise a pair of guide plates having surfaces spaced in said zero clearance fashion, one of said plates being substantially fixedly mounted, and the other of said plates being adjustable with respect to said first plate, and clamping means for holding said adjustable plate in tight fashion in a selected predetermined position.

3. A movie camera as defined in claim 2, in which setscrew means are provided to adjust the gate thickness and cooperate with said clamping means whereby actuation of the clamping means cinches said setscrew means tightly in a desired holding position.

4. In a high-speed movie camera adapted to move a strip of film in stop and go motion through a film gate formed for holding the film positively stationary in exposure position when the camera is subjected to relatively severe conditions of vibration and rapid change of velocity, in combination, a zero clearance film gate, a stationary registration pin mounted in said film gate, and a film-driviNg means;

said clearance film gate comprising an aperture plate having a guide surface for accurately spacing the film in the film gate, and a backing block having a guide surface cooperating with the guide surface of the aperture plate to provide a zero clearance gate, said backing block being adjustable relative to the aperture plate to accommodate film according to the film thickness, and means for fixedly securing said backing block and said aperture plate in the desired adjusted position;

said film drive means comprising a sprocket means formed to engage the film through said holes at two positions on each side of the film gate, guide means for directing the film through a path extending from a supply means past the sprocket to and through the film gate and back through the sprocket to a film-receiving means, and a sprocket drive means for driving the sprocket at a substantially constant speed, said guide means including an eccentrically mounted wheel means positioned for contacting the film in the path between the sprocket means and the film gate and causing the film moving toward said eccentrically mounted wheel means in a substantially uniform velocity to move from said eccentrically mounted wheel means in stop and go motion.

5. A motion-picture camera as defined in claim 4, in which the film drive means also comprises a spring-loaded compensating guide and wheel means positioned on the side of the film gate opposite the eccentrically mounted wheel means and formed for cooperation with the registration pin to hold the film stationary during the stop motion thereof.

6. A movie camera as defined in claim 5, in which the compensating guide and wheel means comprises a pair of springs adapted to yieldably urge the wheel and film strip riding thereover along each side thereof in a direction away from the film gate, and in which side guide means are provided on each side of said compensating guide and wheel means for preventing lateral motion of the film strip as it passes over said compensating guide and wheel means.

7. A movie camera as defined in claim 6, in which a cutoff switch is provided with the cutoff switch having an actuating member yieldably urged toward the edge of the film whereby the switch operates when film is no longer passing by said actuating member, and in which the actuating member acts as part of the side guide means for maintaining the lateral positioning of the film.

8. A movie camera as defined in claim 6, in which certain of the guide means are positioned in close proximity to the sprocket whereby substantially the entire usable area of the sprocket and sprocket teeth are engaged to improve the film grip and prevent undue strain at any single one or small number of said holes at the side of the film.

9. A movie camera as defined in claim 4, in which setscrew means are provided to adjust the film gate thickness and position of the backing block, and means is provided for clamping the backing block securely to said setscrew means.

10. In a high-speed movie camera as defined in claim 1 and adapted to move a strip of film in stop and go fashion through a film gate formed in a magazine section removably attached to a main section adapted to be securely mounted on an aircraft or the like, in combination, means for providing a detachable power connection between said magazine section and said housing, registry means for holding said magazine section in exact position in said housing with the film gate in exact exposure position whereby different magazines may be exchanged in said housing while maintaining substantially the same exposure plane distance from a lens assembly in said housing, and a quick disconnect latch system formed for operative detachment through a single lever and constructed to maintain the two sections positively together and in exact position under severe conditions of vibration and sudden change of velocity.

11. The high-speed movie camera defined in claim 10, in which said guide elemEnts comprise a pair of guide plates having surfaces spaced in said zero clearance fashion, one of said plates being substantially fixedly mounted, and the other of said plates being adjustable with respect to said first plate, and clamping means for holding said adjustable plate in tight fashion in a selected predetermined position.

12. A movie camera as defined in claim 11, in which setscrew means are provided to adjust the gate thickness and cooperate with said clamping means whereby actuation of the clamping means cinches said setscrew means tightly in a desired holding position.

13. A high-speed movie camera as defined in claim 10, in which the film magazine contains a film drive assembly comprising an aperture plate having a guide surface for accurately spacing the film in the film gate, and a backing block having a guide surface cooperating with the guide surface of the aperture plate to provide a zero clearance gate, said backing block being adjustable relative to the aperture plate to accommodate film according to the film thickness;

said film drive means comprising a sprocket means formed to engage the film through said holes at two positions on each side of the film gate, guide means for directing the film through a path extending from a supply means past the sprocket to and through the film gate and back through the sprocket to a film-receiving means, and a sprocket drive means for driving the sprocket at a substantially constant speed, said guide means including an eccentrically mounted wheel means positioned for contacting the film in the path between the sprocket means and the film gate and causing the film moving toward said eccentrically mounted wheel means in a substantially uniform velocity to move from said eccentrically mounted wheel means in stop and go motion.

14. A motion-picture camera as defined in claim 13, in which the film drive means also comprises a spring-loaded compensating guide and wheel means positioned on the side of the film gate opposite the eccentrically mounted wheel means and formed for cooperation with the registration pin to hold the film stationary during the stop motion thereof.

15. A movie camera as defined in claim 14, in which the compensating guide and wheel means comprises a pair of springs adapted to yieldably urge the wheel and film strip riding thereover along each side thereof in a direction away from the film gate, and in which side guide means are provided on each side of said compensating guide and wheel means for preventing lateral motion of the film strip as it passes over said compensating guide and wheel means.