Patent GB-497301-A (GB)
Title: Improvements in or relating to a photographic camera having light sensitive exposureor diaphragm control means
IPC: G03B7/12
Filed: 1937-09-30
Abstract: 497,301. Controlling exposures in photographic cameras. KODAK, Ltd. Sept. 30, 1937, No. 26477. Convention date, Oct. 20, 1936. Addition to 451,658 and 451,659. [Glass 9S (i)] In a photographic camera embodying apparatus for controlling the admission of light to sensitized photographic elements during exposure, in accordance with the parent Specifications, the diaphragm adjusting member is caused by actuation of a film winding or shutter-setting member to occupy one of its extreme positions against spring action, and to be locked in such position until operation of a shutter release member, whereupon the diaphragm is adjusted under the spring action until restrained by the stop which has been locked in the position to which it has been adjusted by the light-sensitive cell. As shown, the pointer 13, Fig. 3, of a meter coil operated by the photo-electric cell is engaged by a comb 126 depending from a lever 27 pivoted at 28. A lever 30 also pivoted at 28 is connected to lever 27 by a spring 32, and carries a pin 36 engaged by a hook 35 on a sliding member 34 pressed forward by a spring 37. A latch 38 has a notch 40 into which the end 42 of lever 30 can enter, and has' a depending arm 43 with a bevelled end 44 overlying an arm 45 forming part of the diaphragm operating lever 21. When latch 38 is rocked, the end 44 forces arm 45 downward to open the diaphragm to full aperture. The shutter operating mechanism is mounted on a plate 46, Fig. 2, hinged at 47 in the upper part of the camera body. The operating arm S of the shutter is adapted to be engaged by link 49. A ring 50 rotatable on plate 46 has a pin 51 projecting into the line of travel of a slide-bar 52 connected by a chain 53 to a winding crank 54. When crank 54 is moved, a lug 58 on bar 52 engages pin 51 and rotates ring 50 against spring 57 until projection 59 engages detent 60, which is operable by finger piece 65 and forms the shutter release. A disc 67 having toothed engagement with ring 50 moves link 49. A downturned end 68 on bar 52 engages lug 69 on a slidable bar 70 having a downturned end 71 engaging the end' 41 of latch 38 to bring the diaphragm to full aperture. The diaphragm is held open by engagement of notch 40, Fig. 3, with the end 42 of lever 30. On releasing the shutter, the release 63 engages an upturned part 72 on bar 34, Fig. 3, which frees lever 30 to move comb 26 across pointer 13. The spring 73 disengages latch 38 from the diaphragm lever 21 and the latter moves until the pin 24 engages the pointer 13. Completion of the movement of finger-piece 65 opens and closes the shutter. Operation of the shutter is prevented if the return stroke of the crank 54 is incomplete. On folding the camera, a cam-like arm 74 strikes pawl 76 to prevent operation of the setting-mechanism until the camera is opened. Manual operation of the diaphragm is effected by moving a plate 78 until an index 81 thereon is at the appropriate point on a diaphragm scale. The projection 91 prevents engagement of the comb 26 with the pointer 13 and itself arrests pointer 13 and diaphragm lever 21. The pin 51 moves an indicator out of an inspection window when the shutter is set, and the indicator returns to view when the shutter is released. Specifications 497,266 and 497,302. are referred to.