GB886826A - Improvements in and relating to photographic cameras - Google Patents

Abstract

886,826. Photographic cameras. VOIGTLANDER A.G. July 14, 1958 [July 12, 1957], No. 22492/58. Class 98(1). A diaphragm, one leaf of which is shown at 21, can be adjusted by two setting members 23, 27, one of these being coupled to a diaphragm-setting ring 11 and the other to the shutter-speed setting ring 10, the latter coupling being such that a constant lightvalue obtains; the ring 10 has an index mark 12 which reads against a fixed scale 13 (giving the shutter-speed value) and another index mark 17 reading against a movable scale 18 (which gives the diaphragm value). Scale 18 is movable by virtue of its being on the ring 11, which also carries a light-value scale 19 reading against a fixed indicator 20. The rings 10 and 11 are retained in any set position by means of respective locating devices 30, 29. The diaphragm 21 and setting members 23, 27 are arranged between the lenses, as shown. Member 23, which has a cam slot engaging the driving pin 22 of diaphragm leaf 21, extends upwards, through apertures in the lens housing 1, 6, terminating in a lug 24 which moves in a slot 25 in the ring 11, said slot running parallel with the optical axis. Thus as the lens housing 1 moves axially under the action of the focusing ring 4, the lug 24 moves in slot 25, so that member 23 and the diaphragm setting ring 11 remain coupled together. Similarly the other setting member 27, connected to the diaphragm leaf by pin 26, is coupled by a long pin 28 to the shutterspeed setting ring 10. The length of pin 28 ensures that coupling is still maintained when the whole of the housing 1, with the lenses and shutter, moves axially as a unit.