Patent GB-296686-A (GB)
Title: Improvements in stereoscopic kinematography
IPC: G03B35/00
Filed: 1927-03-04
Abstract: 296,686. Walker, K. March 4, 1927. Stereoscopic kinematography.-Three films in one plane are exposed through three lenses, the two outer films being moved towards or away from the centre one during exposure, and a composite-image single-width positive film is prepared from them for projection in an ordinary projector; the outer films may be exposed together, and alternately with the central one, to produce negative films in which images and blank spaces alternate, or all three films may be simultaneously exposed. The camera body carries three lenses on a plate attached to its front, the outer lenses being adjustable both horizontally and vertically in relation to the centre one by means of adjusting screws. The films are each carried in a separate spool box in the upper rear part of the camera, and pass over guide rollers and continuous feed sprockets through the gates, being intermittently fed in unison by claw feed devices. Pressure rollers hold the films to the sprockets under the action of springs which extend between lever arms respectively carrying the upper and lower pressure rollers for each film. The spools, Fig. 8, have grooves 37, one at each end, which are engaged by bearing rings carried in the sides of the spool boxes; the spools are also provided with film clips 39a and with spring- pressed bolts 38 which engage recesses in the spindles carrying the spools. The take-up spools 39 are carried in separate spool boxes at the lower rear part of the camera, and are mounted on concentric spindles 40, 41, 42, Fig. 6, each spindle being provided with a grooved belt pulley 40<a> - - 42<a> by which it is driven, and the spindle 42 being formed as one of the spools. The gates. shutters, claw feed mechanisms, &c., are carried by a partition 44, Figs. 10 and 11, arranged transversely across the camera body 1 behind the lenses. The outer gates 81, of usual construction, are carried by parels 82 which are connected to the partition 44 by right-and-left handed screws 85 engaging screwed bearings 83, 84 respectively on the partition 44 and the panels S2. The screws 85 are rocked by levers 86, links 87, and cranks 88, by the camera mechanism, to move the gates laterally during exposures. The films are fed by claws 92 pivoted on a crank pin 94 and have slots 97 in tails 98 engaging a crank pin 96, the pins 94, 96 being respectively carried by gear wheels 95, 90. Exposures are made by means of two oppositely moving blinds 62, 63, Fig. 15, having apertures 64, the blinds being reciprocated vertically by links 71, 72 connected to the ends of levers 53, 54, Figs. 10 and 11; the levers 53, 54 are rocked by links 48<a>, 49a, and levers 48, 49, on a shaft 46 rocked by a crank disc 58 and link 59. The blinds are formed with sockets sliding on rods 66 connected by a plate 67 having holes 68 to engage pins 69 on a supporting plate 70. A single shutter plate 74, Fig. 18, is also reciprocated vertically on rods 73 carried by the plate 67, reciprocation being effected by links 76, 77 connected to levers 51, 52 on a sleeve 50 rocked at half the speed of the shaft 46 by a crank 60 and link 61. The plate 74 is cut so as to comprise wings 79 which mask the outer lenses while exposures are made through the central lens and through an aperture 78 in the plate, and to comprise a part 80 which masks the central lens while exposures are made through the outer lenses. The parts 79, 80 may, if desired, be provided with openings 81 of any suitable size to expose to a greater or less extent, the image areas which would otherwise be unexposed. The three films may be simultaneously punched by punches 102 having cross pins 104, Fig. 13, engaging cam slots 105 in a frame 100 which may be pulled longitudinally by a button 101 against the action of a spring 107.