Patent GB-682255-A (GB)
Title: Improvements in and relating to photographic cameras
Inventor: CLIFFORD THOMAS WILLIAM
IPC: G03B19/04
Filed: 1949-12-20
Abstract: 682,255. Photographic cameras. TAYLOR, TAYLOR & HOBSON, Ltd. Dec. 14, 1950 [Dec. 20, 1949], No. 32562/49. Class 98 (i). A photographic camera of book-form has a centre member carrying the camera lens and two film spools enclosed in outer wing-shaped encasing members which constitute hand grips for holding the camera and are pivotally mounted on the centre member so as to be swingable in arcs about axes parallel with the axes through the film spools, the plane connecting the latter two axes being at right angles to the optical axis in both the folded and the extended positions of the encasing members. The camera shown consists of a fixed tubular-like central member 1 and two wing members 4, 5 linked thereto, Fig. 1. The centre member accommodates the taking lens 2, the view-finder 3 and a shutter, and slidable therover is a shield 6 for covering the lens 2 and the front viewfinder lens when the camera is not in use. A light-tight cover 8, Fig. 3, is hinged to the centre member 1 and is normally located between the wing members 4 and 5, which house frames 17, 17<SP>1</SP> that are hinged to the member 1 at 15 and carry supply and take-up spools 9, 10. After an exposure has been made, a gear segment 14, hinged about the centre member axis 15 and spring biased anti-clockwise has moved to such a position that an edge 18 thereof is engaged by a pin 16 on the frame 17 which is latched at 7 to wing member 4, while a pin 25 thereon engages an arm 24 of a lever 20. This arm is pivoted at 21 and spring urged anticlockwise at 22 so that an arm 23 thereof constantly engages the film on supply spool 9 carried by frame 17. At the same time, a spring-loaded lever 70, Fig. 6, pivoted at 71, has reached a position in which a pawl 72 thereon prevents movement of a pin 59 on an arm 60, which is movable by a shutter release button 50 pivoted at 57, and thus prevents double exposure. In order to move the film on; the camera is closed, causing pin 16 on frame 17 to move the segment 14 clockwise and through gearing 13, 12, 11 to rotate the takeup spool 10 on frame 171. When the segment reaches the end of its clockwise movement, the face 75 thereof disengages the latch 70 from the pin 59, and one end of a lever 76 pivoted at 77 and contacting a part 80 of the centre member 1 moves into engagement with the pin 59; also, a latch 27, pivoted at 28, engages a cam 97 on the segment to prevent anti-clockwise rotation thereof under spring action when the camera is opened. During the opening movement, a cam 42, Fig. 5, on the member 1 moves a lever 41, pivoted at 39, Fig. 4, and having an arm 40 adapted to engage a lever 35, to tension a spring 43, Fig. 5. The lever 41 engages behind a pawl 44 on a pivoted lever 46 engaging one end 48 of a lever 98, pivoted at 63 and spring biased at 64 and having the other end 49 thereof in the path of the pin 59. Also, spool 9 rotates so that a fresh length of film registers with the exposure aperture in the camera and the lever 76 frees the pin 59. When the camera has been opened, an exposure may be effected by depressing the shutter button 50 so that it engages the pin 59 and moves the lever 60 so that a pawl 66 thereon engages a tooth on a ratchet 67 and so that the end 49 of lever 98 is engaged and said lever is tilted. about its pivot 63 and rotates lever 46 so that the pawl 44 thereon releases the lever 41. Spring 43 thereupon moves this lever so that the end 40 thereof moves the lever 35 and through the engagement of this lever with a pin 37 on a shutter arm 30, pivoted at 31 and having a bent part 29 normally covering lens 2, this part 29 uncovers the lens 2 and an exposure is made. Eventually, the arm 40 rides over the lever 35 and the shutter is closed under the action of a spring. When the shutter button 50 is released, the arm 60 returns to its intial position under spring action and causes anti-clockwise rotation of the ratchet 67 so that a pin 69 on latch 27 rides over a ratchet tooth 68 and releases the latch 27 from the cam 97 on segment 14. This segment then moves under spring action into engagement with the pin 16 on frame 17 and thus frees the spring-loaded lever 70 which rotates to re-engage the pin 59 and thus prevent a further exposure. The ratchet 67 forms part of an exposure counter 65, the readings on which are visible outside the camera body. To make another exposure, the procedure described is repeated. A timed exposure can be effected by rotating a knob on the outside of the camera so that the end 93 of spring 43 rests on the cam surface 91 of a member 90 which is rotated by this knob and so that a lever 54 engages a dwell 92 in said member. The arm 54 is pivoted and engages lever 98 at 53 and has a step cam 56 which during the exposure movement of the shutter arm 30 engages the lever 41 when the shutter is still open. The shutter remains open until the release button 50 is allowed to return to its initial position whereupon the anti-clockwise movement of lever 98 rocks the lever 51 and so moves the cam 56 out of the path of the lever 41. After each exposure, the ratchet 67 is rotated through one tooth pitch by the return movement of lever 60 and when the film has been exposed, the pin 69 on latch 27 engages a dwell 11 on the ratchet so that the segment 14 remains free. At the same time, a lever 85, pivoted at 86, engages a dwell 84 on a further cam 82 so as to lie behind pin 59 and this prevents actuation of the release button 50. Hence, the camera can now be opened and closed a sufficient number of times to wind up all the film on to the spool 10. To re-load the camera, latches 7, 71 are released and the wing members opened out wide giving access to the spools 9, 10. A new spool 9 is inserted and the film threaded on to the spool 10. The camera is then closed so that latches 7, 7<SP>1</SP> re-engage. When the camera is next extended it is locked in position by a bell-crank having a pawl engaging a notch in a cam on the member 8, which is secured to wing member 5 by a sliding latch 103 integral with latch 7, Fig. 4. The counter 65 is then normally rotated so that the pin 69 lies at the end of cam dwell 81 and lever 85 has been rotated clockwise by cam 82 to release button 50. The counter is again rotated so that pin 69 again engages a ratchet tooth 68. By opening and closing the camera a number of times, each time the camera is opened releasing the shutter button 50, the leader strip of the film is wound on. When the leader strip has been fully wound on the spool 10, a cam dwell on the cam 82 allows lever 85 to re-engage pin 59 to prevent a shutter actuation. In this position, the pin 69 on latch 27 engages a cam dwell 99 on ratchet 67. The counter is then rotated one division so that the lever 85 is moved out of locking engagement with pin 59 by the cam 82. The shutter may then be actuated to take the first picture.