GB135865A - Improvements in Safety Devices for Cinemotograph Projecting Apparatus. - Google Patents

Abstract

135,865. Stein, F. Nov. 28, 1917, [Convention date]. Kinomatograph apparatus.-Relates to kinematograph projectors having means whereby (1) breakage of the film above the first feed sprocket, or (2) piling up of the film below this sprocket, caused by interruption of the feed, closes the circuit of an electro-magnet to release a shutter which cuts off the light beam, and consists in mounting two contact levers or flaps, one resting on the film above the first sprocket, and the other operated by the accumulation of the film, on the same pivot pin; movement of either lever or flap may also break the driving-motor circuit, and switch on the hall lights. As shown, a roller 6<a> on a flap 6 pivoted at 17 bears on the film 1, the flap being provided with a guard-plate 7. The flap is insulated from the frame 14 of the apparatus, and connected by a conductor 16 to one terminal of the electro-magnet 10, the other terminal being connected by a conductor 15 to the frame 14. When the film breaks, the flap 6 falls and engages a spring contact 12, causing the electro-magnet circuit to be completed. The armature 11 of the magnet is then attracted and a hook 9 carried by it is removed from under a shutter 8, thus allowing the shutter to fall to cut off the light. If the film collects between the sprocket 2 and the gate, it is caused by a guide 24 to engage and lift up a flap 22, this flap being mounted at 17 on the same pivot pin as the flap 6, and having an arm 23 which then engages the guide 24 and completes the electro-magnet circuit to release the shutter. The switch arm 30 for the driving motor may carry an arm 30a which is engaged by a lever 34 when the current passes, a spring 33 tending to break the circuit. The lever 34 carries a pin 35 engaging a sliding bolt 36. When the shutter falls it strikes the head of the bolt 36, depresses the lever 34, and allows the spring 33 to break the circuit. A contact 38 may be provided which then becomes engaged by the switch arm 30 to complete the circuit for the hall lights.