GB853632A - Improvements in and relating to photographic cameras - Google Patents

Abstract

853,632. Photographic cameras. VOIGTLANDER A. G. Feb. 26, 1957 [March 1, 1956], No. 6443/57. Class 98(1) Apparatus for adjusting the shutter speed or diaphragm aperture in a photographic camera has a number of groups of symbols, each group referring to a different exposure factor, and manipulating means associated with each group and adjustable with respect to the symbols therein for operating a calculating mechanism, the output of which is conveyed to the shutter speed or diaphragm aperture setting member. As shown in Fig. 1, a photographic camera has an objective 3 with a rotatable focusing ring 4. The objective mount houses an iris diaphragm with two adjustment members, viz. a member 5 and a pointer 6 movable with respect to a scale 7 of film speed, filter factor or other fixed exposure factors. Four adjusting knobs 9, 10, 11, 12 are slidable in parallel slots in a wall 8 of the camera knob 9 moves with respect to a scale of shutter speeds; knob 10 to a series of symbols indicating weather conditions; knob 11 to symbols indicating subject reflectivity; and knob 12 for symbols for near, mid-distant and distant subjects. The symbols of the last three scales may be pictorial as shown, or may consist of letters or numbers. Each knob is connected to a slider 13, 14, 15 or 16 having a slot 17, 18, 19 or 20 engaging a pin 22, 23, 24 or 25. Wedges 26, 27, 28, 29 are pivoted to the pins connecting the knobs to the sliders, or, in a modification, are connected to the sliders in such a way as to allow transverse movement only with respect to the sliders. A slider 35, having an arm 34 engaging the adjusting member 5 of the iris diaphragm, is urged by a spring 36 against one surface of wedge 29. Other sliders 37, 38, 39 are placed between the wedges so that the upper surface of wedge 26 is urged against a stop 52. If knob 9 is set to a required shutter speed, a wedge 62 connected to slider 13 sets the shutter through action of a slider 63. Knobs 10, 11, 12 are set in accordance with the light and subject conditions, whereupon the diaphragm aperture is set through action of slider 35. The setting of knob 12 also focuses the objective, through action of a wedge 57 on a slider 59 with an arm 60 connected to the focusing ring 4. The stop 52, Fig. 2, slides in a bore in the camera wall. The upper part of the bore is threaded to receive a screw 49. A spring 55 is trapped between screw 49 and stop 52, but its action is overcome by the action of the stronger spring 36, so that projections 50, 51 on the screw 49 and the stop 52 respectively are forced into contact. If the settings of knobs 9-12 are such as to require the diaphragm to be set beyond the limit of its adjustment, then either the wedges cannot be moved or wedge 26 is not urged against stop 52, which is moved along its bore by spring 55 until a red surface 53 thereon becomes visible in a window 54 formed in the camera wall.