Patent GB-706890-A (GB)
Title: Improvements in and relating to photographic roll film cameras
IPC: G03B17/42
Filed: 1952-05-23
Abstract: 706,890. Photographic cameras. VOIGTLANDER AKT.-GES. May 23, 1952 [May 23, 1951], No. 13178/52. Class 98(1) In a photographic roll-film camera having an objective, a shutter for the objective, means for winding the film, means locking the film winding means which prevent winding of the film before the section in the camera gate has been exposed, and means for both actuating the shutter release and releasing the said locking means, there is arranged between a manually operable member having a return spring, and actuating or releasing members for the shutter release and the locking means, a spring (or corresponding acting energy storer) guided in the direction of movement of the actuating or releasing members, in which energy is stored by the action on one end of it by the manually operable member as the latter is depressed while its other end acts upon or constitutes an intermediate member also guided in the direction of movement of the actuating or releasing members, which intermediate member is first retained by a catch while energy is being stored in the energy storer and when the latter is completely charged is released by action of the manually operable member, whereupon the intermediate member is moved against the actuating or releasing members independently of external influences, the energy storer being so proportioned that when the intermediate member is released sufficient energy is exerted by it to ensure reliable actuation of the shutter release and release of the locking means. As shown, a hollow plunger 7 is slidable in a cylinder 5 fixed to the camera casing 1, a projection 9 thereof sliding in a slot 10 in the cylinder. A twisted rod 12 fast with a shaft 14 lies in the cylinder and engages a slot 11 formed in plunger 7. A toothed wheel 16, fast with an eccentric 15, a collar 19, and a cam 17, is slidable on shaft 14, a spring 55 acting to press collar 19 against a pin 18 on shaft 14. When plunger 7 is pushed down against action of a spring 6, shaft 14 is rotated, and pin 18 engages the vertical face of cam 17 to rotate wheel 16, which drives a gear wheel 4 which drives the filmwinding spool 2 through means (not shown) which take account of the increasing diameter of the film roll so that the film is wound by the length of a picture frame. During the return stroke of plunger 7, shaft 14 is rotated in the opposite direction, and pin. 18 engages the sloping surface of cam 17, which, together with collar 19, wheel 16 (which remains in mesh with wheel 4) and eccentric 15, is moved upward against action of spring 55, until a lug 20 on a slidable spring-urged rod 21, which normally rests on the periphery of collar 19, moves under the collar, thus holding cam 17 clear of pin 18. Depression of plunger 7 no longer winds the film until the shutter has been released. This is effected by means of a knob 41 on a rod 42 slidable in the casing. A disc 46 slidable on rod 42 is urged by a spring 45 against an end flange 47, and is held peripherally by a pivoted catch 49. When knob 41 is depressed against action of a return spring 44, spring 45 is compressed between a disc 57 fast on rod 42 and the disc 46. Disc 57 encounters an inclined part 58 of catch 49 and, at the end of its stroke, rocks it to release disc 46 which is forced by spring 45 to the end of rod 42, encountering the end 30 of a lever 27, which acts on rod 21 to withdraw lug 20 from under collar 19, and at the same time disc 46 strikes the turned-up end 36 of a slidable rod 32 which acts on the release 34 of the shutter 35. On release of knob 41, disc 46 encounters another bevelled part of catch 49 which re-engages the disc. In a modification, disc 46 is replaced by a pivoted lever and an abutment surface is fixed just below the ends 30, 36.