Patent GB-896579-A (GB)
Title: Improvements in or relating to photographic cameras
IPC: G03B7/12
Filed: 1959-09-09
Abstract: 896,579. Photographic cameras. GAUTHIER G.m.b.H., ALFRED. Sept. 9, 1959 [Sept. 17, 1958], No. 30733/59. Class 98(1). [Also in Group XL(b)] In a photographic camera with setting members for exposure time and diaphragm aperture, for setting different exposure times within a range of uniformly graduated times suitable for hand held exposures, the exposure time setting member is movable in relation to a film sensitivity scale, whilst the diaphragm setting member is coupled to a photo-electric control device, by which adjustment of the diaphragm is effected in accordance with existing light conditions. As shown (Figs. 2 and 5), the shutter speed setting means of a camera objective comprises a first setting ring 9 which bears an index 11 for co-operation with a fixed film sensitivity scale 8, and a second setting ring 10 which may be coupled to said first ring 9 by means of a manually actuable spring catch 17 (Fig. 8) and is rigidly connected to a speed control cam-ring 12. The diaphragm setting means comprises a blade actuating ring 27 (Fig. 11) which has blade actuating cam slots 27a therein and may be set either by a photo-electric control device (for continuous light photographs) or by a manual setting ring 20 (for flash photographs). Continuous light photographs. By means of spring catch arm 17a and recess 9b, the rings 9 and 10 are rigidly coupled together in relative positions such that setting symbols 13, 14 coincide. The shutter speed is then set according to the sensitivity of the film in use by rotation of both rings 9 and 10 relative to scale 8. As a result of the diaphragm actuating ring 27 being coupled to the shutter cocking spindle 41 (Fig. 10) by way of gears 44, 42 ring 39 and engageable projections 39a, 27c, said ring 27 is rotated into an end position against the tension of a spring 28 on cocking of the shutter and is held there by means of a spring urged latch 46. On depression of a shutter release 48, latch 46 is released and ring 27 runs down under loading of its spring 28 until one of the steps 27b (Fig. 19) engages with a movable stop 27c on a spring urged lever 37 which is positioned by coupled feeler levers 29, 30 pivoted at 31, 32 respectively in accordance with the deflection of the galvonometer 24 connected to a photo-cell (not shown). Flash photographs. By means of spring catch arms 17b and a recess 4a in a fixed housing member 4, the ring 10 is moved to a fixed position in which setting symbols 15, 16 coincide and which is associated with a speed of say 1/30 sec. During this adjustment, a cam portion 10b (Fig. 5) on ring 10 raises a spring urged locking pin 19 out of a recess 20b in the manual setting ring 20 whereby this ring is liberated. At the same time the galvonometer is short circuited, or switched out of circuit, so as to render it inoperative and latch 46 is moved into an ineffective position by cam portion 19a. The diaphragm ring 27 is now controlled by the ring 20 through engaging protractions 20b, 27c and is no longer held by latch 46 in the tensioned position when the shutter is cocked. To assist in the setting of the diaphragm, the ring 20 is provided with a rotatable ring 55 thereon, the setting procedure being as follows. Ring 55 is rotated relative to ring 20 by means of a grip 59 until an index 57 registers with the indication mark of the flash bulb being used on the scale 56. Rings 20 and 55 are then rotated together until the desired distance on the scale 58 registers with the mark 11 on ring 9 (which ring is still set to the relevant film sensitivity value on scale 8). To prevent adjustment of the rings 10 and 12 when the camera is set for flash photographs and the ring 20 is not in its end position, a locking pin 25 is provided, which ring co-operates with a cam recess 20c in the ring 20 and with the recess 12b in the ring 12. During return movement of rings 10 and 12 to the continuous light setting position, an arm 50 (Fig. 16) comes against a projection 27d on the ring 27 and moves this ring into its cocked position in which it is retained by the once more effective latch 46. A cam portion 51 is provided on the housing 1 to release the arm 50 from the projection 27d after the ring 27 has reached its cocked position. In modifications, the diaphragm (for continuous light photographs) may be automatically set by means of a suitable photo-electric device or may be coupled to a follow up point of an exposure meter. A warning device may be incorporated to indicate when the ambient light is insufficient or too great for proper exposure, and the diaphragm may be replaced or supplemented (in known manner) by neutral or polarization filters. Specification 868,648 is referred to.