Patent GB-719323-A (GB)
Title: Improvements in and relating to photographic roll film cameras
IPC: G03B1/48
Filed: 1952-02-19
Abstract: 719,323. Photographic roll film cameras. VOIGTLANDER AKT.-GES. [formerly VOIGTLANDER & SOHN AKT.-GES.]. Feb. 19, 1952 [Feb. 19, 1951; June 16, 1951] No. 4383/52. Class 98(1) In a roll film camera having a film presser plate which is released from the film during winding by means of one or more wedge devices, the presser plate and wedge devices are mounted on the rear wall of the camera and the wedge devices are releasably connected with parts connected to the film winding mechanism so that the connection between this mechanism and the wedge devices is broken when the camera is opened by movement of the rear wall and is re-established when the camera casing is closed. As shown in Fig. 2, the film presser plate 4, recessed at 11 to receive leaf springs 12 which are held in place by cross pins 38 and which have extensions 13 riveted at 31 to the openable camera back 33 (Fig. 3, not shown) towards which they urge the plate 4, has a lateral projection 6 engaged by a bent-up lug 15 on a pivoted lever which is urged anti-clockwise through a pivoted lever 21 pinned to it at 19 and engaged by a lateral arm 25 on an upwardly urged plunger 26 which is depressed manually to operate the film winding mechanism. Thus on closing the camera back which is hinged to the body, the bevelled under-face 7 of the projection 6 engages the lug 15, thus moving the plate 4 across the width of the film. whereupon by engagement between frustoconical rivet heads on the camera back with similar recesses 8, 9, 10 in the plate 4, the plate is moved towards the exposure aperture to clamp the film 3, said rivet heads resting in the recesses clear of the sides when the camera is open. When the plunger 26 is depressed to wind the film, the lever 16 is freed to move clockwise under the action of the springs 12 so that they are enabled to pull the plate 4 clear of the film to permit it to wind freely. In a modification in which the camera back is closed by a sliding movement across the film width, the projection 6 is not bevelled and the plate 4 is provided with projections having leading bevels extending in the direction of movement and out from the clamping face of the plate 4 to prevent the edge of the plate or the projection 6 from catching the film. In a further embodiment, Fig. 7. leaf springs 7 are rivetted at 6 and 8 respectively to the presser plate 4 and the camera back (not shown). A T-shaped member 11 having a loose pin-and-slot mounting 10, 12 on the camera back which is dished to house it, is provided on its cross bar with inclined portions 15 which engage the conical heads of the rivets 6 and on its stem 13 with a bevel 23 engaged by the lever 18 urged anti-clockwise by the return spring of the film winding mechanism plunger. By this arrangement the Plate 4 can rock slightly to allow for inequalities in spacing of the back and exposure frame. A similar result may be achieved in the Fig. 1 embodiment by using only one or two wedge devices suitably disposed. In a modification (Fig. 9, not shown), the T-member 11 (Fig. 7), is replaced by a slidable bar having a transverse downwardly extending ridge and the plate itself bears a conical rivet head. If desired the locations of the stud and recesses may be interchanged between the presser plate and the rear wall.