GB1150213A - Interchangeable Camera-Lens Mount. - Google Patents

Abstract

1,150,213. Interchangeable lens mounts. VEB CARL ZEISS JENA. July 4, 1966, No.29937/66. Heading G2A. An interchangeable lens mount has a diaphragm 2 which, at the moment of release of the shutter of the camera to which the mount is attached, closes down to a preselected stop value and after exposure is re-set to its initial position, and a sensing needle 16 for the transmission of a preselected stop value from a diaphragm setting ring 10 to a calculating mechanism in the camera housing, the needle being movable to and fro for use with cameras having a calculating mechanism and being completely retractive into the lens mount for use with cameras without a calculating mechanism. This calculating mechanism processes the film speed value, the preselected diaphragm value, and a photo-electric exposure meter value obtained by either through, or outside, the lens metering, and finds the exposure time which is then transmitted automatically to set the shutter. For through the lens metering, the diaphragm setting ring is locked with a transmission ring 13, as shown. When the diaphragm value is set against a pointer 11 an inclined edge 13' causes the needle 16 to project out of the lens mount to a greater or lesser extent and this indicates the preselected stop value to the calculating mechanism. Depression of the shutter release causes a push rod 3 to be moved to the right, allowing a three armed lever 7 to pivot clockwise until the arm 7"' thereof contacts the ring 10 at a position depending on the selected diaphragm value. The arm 7' has moved so as to allow the diaphragm to close down to this value. After the exposure, the push rod 3 moves to the left and the diaphragm 2 returns to its initial position. For outside the lens metering, a ball 14 of the ring 13 locks in a recess 10"'. The diaphragm value is selected as before and the needle 16 will project a known amount from the mount, e.g. for a value f2À8, the needle projects 1 m.m., and will always project 1 m.m. for f2À8 irrespective of whether this lens is used, or another lens having a different diaphragm range. This amount, e.g. 1 m.m., is transmitted to the calculating mechanism which sets the shutter speed as before. For cameras without a calculating mechanism, the ball 14 locks in a recess 10"" and the needle touches the portion 13" of the ring 13, and remains wholly inside the lens mount whatever diaphragm value is selected.