GB786184A - An arrangement for photographic cameras - Google Patents

Abstract

786,184. Photographic cameras. DECKEL, H., and DECKEL, F. W. Jan. 16, 1956 [Feb. 1, 1955], No. 1398/56. Class 98(1) In a photographic camera, the diaphragm setting member can be adjustably coupled with either the shutter speed setting member or the focusing member. As shown in Fig. 2, focusing ring 16 is threaded into a flange 12 on the camera body, and imparts axial movement to a tube 18, which is held against rotation by a plate 30, entering a slot in the tube. The shutter housing 34 is mounted on a ring 22 carried by tube 18, and includes a shutter speed setting ring 42 and a diaphragm setting ring 40. Ring 40 is connected to a coupling ring 48, which rotates between a flange of a ring 20 fixed to tube 18, and a skirt 44 of the shutter speed setting member 42. A follower ring 94 is rotatably mounted on ring 20, and is connected to the focusing ring 16 by means described in Specification 786,185 whereby ring 94 is driven by ring 16 in such a way that the angle through which it turns is proportional to the distance indicated on the scale on ring 16. A coupling claw 54 is slidable longitudinally on ring 48, and has teeth at both ends which engage corresponding teeth 46 on the skirt 44 of the shutter speed setting member 42, or teeth 124 on ring 94, according to its position. A slide member 66 (Figs. 5 and 6, not shown) controls the movement of the claw so that ring 48 may be coupled with either the shutter speed setting member or the focusing member (through ring 94). In either position, the claw'54 may be moved for adjustment, but the amount of movement possible is not enough to engage the other member. When photographs are to be taken by flashlight, the rings 48, 94 are coupled and are relatively adjusted in accordance with the guide member for the flashbulb. Thereafter when the camera is focused at any distance the diaphragm aperture is also varied through the coupling to keep the product of diaphragm aperture and focusing distance constant. Under other lighting conditions, the rings 48, 42 are coupled and are relatively adjusted in accordance with the light intensity. Thereafter the shutter speed and diaphragm aperture may be varied together without altering the effective exposure.