Patent GB-819744-A (GB)
Title: Improvements in or relating to cinematographic cameras
IPC: G03B19/18
Filed: 1956-10-05
Abstract: 819,744. Kinematograph cameras. ROYET, P. F. Oct. 5, 1956 [Oct. 5, 1955], No. 30459/56. Class 97(1) A camera in which the two longitudinal halves of the film are exposed while winding in opposite directions has exposure apertures on either side of the longitudinal centre line of the film and displaced in the direction of film feed, the objective being mounted on a shaft for movement between positions where it registers with the respective apertures, the consequent shaft rotation producing the necessary reversal of film feed In the form shown the film is fed from a detachable spool 5 to a permanently mounted spool 6 during exposure of a first half of the film width and rewound for exposure of the second half, the camera being inverted during this half. The film is led round rollers 7, 8 past claws 16a, 16b connected by a spring 21 and both driven from the crank 18 actuated by a spring motor not shown. One claw is held out of contact with the film by an abutment 22, the other is engaged and disengaged, to produce the film feed, by a cam 19 also so actuated. The objective 12, (see also Fig. 4) is movable on a shaft 9 to align it with exposure gates 13, 14 alternatively. The shaft 9 carries a gear 93 engaging a gear 94 carrying the abutment 22 so that movement of the objective changes the claw which is disengaged and reverses the direction of film feed. The camera motor also drives through gearing 42, 43, 44, 45, 47, 48 a shutter shaft 50 and thence, through gearing 49, 57 a governor shaft 52. The pinions 45, 47 are mounted on a shaft 46 which carries a pulley 54 driving through a belt 55 a pulley 56 driving a friction member 87, engageable alternatively, by movement of a pivoted lever 83, with friction members 88, 89 on the spool spindles. The camera mechanism drives a shaft 58, Fig. 16, which drives a footage indicator, not shown, and carries cams 59, 61. When the film has been wound for the exposure of the first half the cam 59 lowers a member 65 to obscure the viewfinder 34. The cam 61 has a notch into which a follower 68 is moved under the action of a spring 100, the follower being on a lever 69 pivoted at 71. This movement brings an abutment 72 into the path of a cam 53 on the governor shaft to prevent further movement. When the shaft 9 is rotated clockwise by movement of the objective to align it for exposure of the second half of the film a cam 75 engages an abutment 90 on the lever 69 to lift the lever to permit further movement. The shaft 9 also carries a lever 74 which, as the shaft is rotated, locks the camera door by the hooked end 77, and removes a member 76 from the viewfinder 35 while the end 81 engages the end of the lever 83 to move the friction drive by the member 87 from one spool to the other. The objective may be secured in one or other of its operative positions by a spring loaded plunger engaging alternative holes in the camera body. A spring blade within the camera may engage the shutter and prevent operation of the camera unless disengaged by the plunger projecting within the camera. A pivoted or sliding masking member may be actuated by the rotation of the shaft 9 to cover the exposure gate not in use.