Patent GB-810633-A (GB)
Title: Improvements relating to film conveying devices for mirror cameras
IPC: G03B17/17
Filed: 1957-02-05
Abstract: 810,633. Photographic and kinematographic apparatus. BOK, R. Feb. 5, 1957 [Feb. 6, 1956], No. 3974/57. Classes 97(1) and 98(1) In a device for conveying separate pieces of cut film to and from the image area is a mirror camera (i.e. a camera in which the image is formed by a concave mirror and lies on a curved surface), said device being of the type comprising a frame with two parallel guiding grooves adapted to extend transversely through the camera for guiding the side edges of the pieces of cut film during their conveyance, an exposure gate situated in the image area, and a pad for pressing the cut films against the exposure gate during exposure so that they conform to the curved image surface, the means for conveying the cut films through the parallel guiding grooves comprise two endless bands which are arranged to be driven in a slip-free and intermittent manner parallel to the guiding grooves and which are provided with projections for engaging the rear edges of the pieces of cut film for moving them through the parallel guiding grooves. In the form shown in Figs 1 and 2, the device comprises a frame 1 from which extend parallel bars 2, 3 having guiding grooves 4 for the reception from a supply magazine 5 of pieces of cut film. The pieces of film in the stack contained in the magazine are spaced apart by a cardboard spacer 6 arranged in zig-zag fashion, the stack is compressed by a spring 7, and the magazine itself is spring-urged at 8 towards the bars 2, 3. The dimensions of the spacer 6 are such that it can pass between the bars 2, 3 and that each piece of film as it is pushed into the grooves 4 can be engaged at its rear edge by a projection 15 on endless conveying hands 9. These hands are intermittently driven by rollers 11 operated by a motor-driven shaft 18 and a Maltese cross mechanism so as to feed the film pieces separately to an exposure gate 25. Behind this gate is a convex pressure pad which, when bands 9 are stationary, is reciprototed by cams 27, 28 on the shaft 18 so as to press a film piece into a curved shape and allow exposure. When the pad has moved back, the exposed film is carried forward by the hands to a supply magazine. In another embodiment, Fig. 5, the pieces of cut film are removed from a supply magazine (not shown) by a projection 51 on an endless hand 48, driven by one set of teeth on a motor operated gear 55 so that the rear edge of each piece of film will be engaged by a projection from each of two endless bands 36, 37 driven by rollers 39, 40 on a shaft 38 which is intermittently operated by another set of teeth on gear 55 in such a way that the hands 48 and 36, 37 move in synchronism. The bands 36, 37 intermittently feed film to an exposure gate when a pressure pad 71 is also moved in synchronism into and out of contact with the film by a bar 70 through which passes horizontally a slide 68 having an inclined slot engaged by a pin on the bar 70, this slot being coupled to a wheel 59 rotated by a third set of teeth on gear 55. Slide 68 is also coupled to a pivoted lever 73 for reciprocating a push rod 75, one end 76 of which is adapted to engage the rear edge of each piece of film and push the latter into a take-up magazine (not shown). In each embodiment, the conveying bands may have a second set of projections each spaced from the conveying projections by the length of a film piece.