Patent GB-532610-A (GB)
Title: Improvements in or relating to photographic cameras
IPC: G03B17/42
Filed: 1939-09-11
Abstract: 532,610. Roll film photographic cameras. KODAK, Ltd. Sept. 11, 1939, No. 25603. Convention date, Sept. 9, 1938. [Class 98 (i)] In a roll-film camera the lens mount and shutter are carried by a telescoping tubular structure within which is a shutter actuator axially movable therewith and adapted to be rotated from the camera body in one direction to set the shutter and in the other direction to release it. In the camera shown, the shutter 29 carrying the lens elements is mounted in a tube 31 engaging by means of a multiple thread screw within a tube 34, which engages by threads of opposite hand. within a collar 36 fixed to the front of the camera. Rotation of the tube 34 by means of a knurled rim 43 moves both tubes outwardly or inwardly for focusing, the tube 31 being prevented from rotating by pins 37 extending from it through slots in brackets 30 which are secured to the aperture frame at the back of the camera. Fine focusing is performed by a knob 44, through gears 46, 47, 48 and an elongated pinion 49 which engages a gear ring 51 on the rear end of the tube 34. Rotatably carried in the tube 31 is a shutter-actuating member, shown separately in Fig. 16, in the form of a skeletonized tube 52 having at the front end a lug 54 which, when the tube is rotated from its mean position, engages and operates either the shutter setting member 55 or release trigger 56. Slot 53 in the tube engaged by the pins 37, prevent axial movement relatively to the tube 31. The actuator tube is moved by means of a gear segment 60 which engages in all axial positions of the tube in a broad rack-member 61 slidably mounted on the bottom of the camera body. Movement of the rack to the right, to rotate the tube anticlockwise to set the shutter, is produced by rotating a vertical shaft 64 carrying an arm 66 connected by a link 67 to a lever 68 having a slot in which engages a pin 70 on the rack. Reverse movement of the rack and tube, to release the shutter, is produced by depression of the rod 72 which carries the release button, and which moves a bell-crank lever 76 to cause an arm 78 pivoted to it to move to the left and engage a shoulder on the slide 61. On the return movement the arm 78 rides up over a pin 85, which lifts it clear of the shoulder on the rack. A two-armed spring 81 engaging a lug on the arm 66, biasses the rack to its central position. The shutter-setting means are operated by the film-winding means, and interlocking means are provided to prevent double and blank exposures. Fig. 1 shows the parts in the position they occupy when ready for an exposure. When the rack 61 is moved to the left by operation of the shutter release, as above explained, it causes through the linkage 68, 67, 66 an anticlockwise rotation of the shaft 64. An arm 107 at the top of this shaft engaging an interlock lever 115 rotates the latter about its pivot 116, and a lug 118 on the end of this lever moves out of a slot 112 in a disc 110 rotatably mounted on the film winding spindle. A spring 122 then moves the lever 115 to the left, to the extent permitted by the slot 117 in which the pivot pin 116 engages, thus withdrawing its end 132 from a spring-urged pivoted arm 127 which then moves to engage in a notch in the finger release when the latter is freed, so preventing its being depressed a second time. The film is then wound on, and a gear (not shown) secured to the film-winding stub-shaft 91 rotates a mutilated gear 96, which through a link 99 pivoted to it and the arm 107 rotates the latter clockwise, and with it the shaft 64. The rack 61 is thus moved to the right, rotating the tube 52 so that the lug 54 on it engages and operates the shutter-setting member 55. The film passes over toothed rollers on a shaft 24a, which is thus rotated during winding of the film, and through gears 103, 104 rotates a gear 102 which is loosely mounted on the shaft 91, and which rotates the disc 110 through a friction drive. After the mutilated gear 125 has rotated to a position in which it is out of mesh with the gear on the shaft 91, allowing winding to be continued until a full frame has been wound on, the slot 112 in the disc 110 again engages the lug 118 on the interlock lever 115 and pushes the lever to the right until the lug falls behind a shoulder 120 on a fixed plate 105, thus latching the lever, a prong (not shown) on which then engages the wheel 102 and locks it so that the film cannot be further wound. At the same time the end 132 of the lever moves the arm 127 to free the shutter release, and a lever 123 connected by the spring 122 to the lever 115 moves so that a cam surface 134 on it engages a pin 126 on the mutilated gear 96 and rotates the latter until the commencement of the toothed portion is again engaged by the gear on the shaft 91, ready for the next cycle of operations. To enable the film to be freely wound at the time of insertion or removal, the lever 115 may be moved by an externally-operated forked lever 146 so that it does not lock the gear 102.