GB778209A - Improvements in photographic cameras - Google Patents

Abstract

778,209. Photographic cameras; lens mounts. VEB C. ZEISS JENA. Sept. 15, 1955, No. 7008/54. Classes 97(1) and 98(1) In an interchangeable lens mount for a single lens reflex camera in which the diaphragm may be held fully open for focusing and is closed to a predetermined adjustable stop value on making the exposure, the diaphragm is brought to its fully open position on setting the camera shutter, and the diaphragm operating means is disposed wholly within the camera and can only be operated by operations performed on the camera shutter. On releasing the shutter in the forms shown, spring 45 closes the diaphragm to a position determined by stop 17 which is pre-set by ring 21. In Fig. 2 the shutter release moves toothed wheel 37 in the direction of the arrow B by means of shaft 39 so that it disengages toothed rim 36 of annular member 35 rotatable in camera housing 31. Spring 45 then rotates both member 35 and diaphragm operating ring 8 until should 11 of ring 8 abuts stop 17. As shown in Fig. 4 disc 50 enters a notch in ring 47 which is rotatable with ring 8 through engagement of a forked shoulder 48 thereon with diaphragm operating pin 12. The shutter release drives rod 54 in the direction of the arrow C, thus releasing ring 47 for rotation with ring 8 under the action of spring 45. Shaft 43 is connected to the shutter setting mechanism of the camera and, on setting the shutter, member 35 is rotated to open the diaphragm against the action of spring 45. In Fig. 4, shaft 43 is also rotated against the action of tension spring 60, when disc 50 has locked ring 47, spring 60 rotates stop 46 away from pin 12, clutch 44 being disengaged when rod 56 is moved in the direction of the arrow D by the shutted release. Clutch 44 also allows the rotation of shaft 43 to continue when annular member 35 is stopped by operating pin 12. Ring 21 is normally locked in notches 23 by spring 20 and must be pressed inwards to adjust the position of the stop 17. Focusing is effected by rotating ring 26 and the lens mount is prevented from rotating by the engagement of lug 32 in groove 33. The film wind may be coupled with the shutter setting machanism of the camera.