A film cartridge designed to carry an endless roll of film having a rotatably-mounted drive member with a central hub portion and a flange portion. The spiral roll portion of the endless film is disposed about the central hub portion and is loosely contained between the flange portion and a support surface perpendicular to the rotational axis of the drive member. The inner end of the spiral roll extends as a single loop upwardly and forwardly through a film guide passageway to the front wall of the cartridge, where there are openings provided in the film cartridge housing to receive the various movie projector operating components before returning to the outer convolution of the spiral roll. The drive member has a pair of diametrically-opposed friction pads disposed on the innermost edge of the hub portion to impart a momentary increase in the frictional force applied to the innermost convolutions of the spiral roll during each revolution of the disc. To assist the spiral roll in moving its inner convolutions towards the hub portion, the space in between the flange portion surface and the support surface increases in a radial inward direction. The inner convolution is urged positively away from the disc by employing an annular step formed around the innermost end of the hub portion. The inner end of the spiral roll is pushed off the hub and towards the film gate by driving the disc at a speed greater than can be accommodated by the claw drive mechanism of the movie projector so that a compensated loop is formed in the film guide passageway to provide a supply of film for the claw drive mechanism used to advance the film frame by frame through the film gate.
Cassette for an endless type cinefilm comprises a casing containing therein the film coiled to form windings thereof supported and guided between outer and inner guide rings. The casing has a film gate across which a portion of the film pulled out of the innermost winding of the windings of the film through the outlet cut-out portion of the inner guide ring is moved for the projection or the exposure of the film. After having moved across the film gate, the film is advanced into the inlet cut-out portion of the outer guide ring to merge into the outermost winding of the windings of the film. The casing is provided with an arcuate guide member for the film located outside of the outer guide ring at a position remote from the cut-out outlet portion of the inner guide ring through which the portion of the film is pulled out from the innermost winding of the film. The arcuate guide member is arranged obliquely with respect to the direction of movement of the portion of the film moved from the outlet cut-out portion to the arcuate guide member so that the portion of the film is twisted by 90.degree. so as to maintain the plane of that portion of the film closely adjacent to the upper end face of the windings of the film normal to the axis thereof while the portion of the film after having been guided by the guide member is twisted by 180.degree. while changing the direction of movement thereof so that the plane of that portion of the film after having been guided by the guide member is held closely adjacent to and parallel to the plane of the opposite lower end face of the windings of the film and in a plane lying within the width of the film forming the windings normal to the axis of the windings thereby permitting the internal dimension of the casing in the axial direction of the windings to be made only nominally greater than the width plus the thickness of the film rendering the thickness of the casing to be made to the minimum.
