Patent GB-961993-A (GB)
Title: Magazine photographic camera
Inventor: WOODCOCK EDWARD CECIL
IPC: G03B17/42
Filed: 1961-04-07
Abstract: 961, 993. Magazine cameras. WILLIAMSON MANUFACTURING CO. Ltd. July 4, 1962 [April 7, 1961], No. 12637/61. Heading G2A. A magazine camera in which the driving energy is stored in a main spring has a first escapement controlling said energy to change the film and wind up a secondary spring which sets the shutter, and a second escapement which allows the secondary spring to operate the shutter, the two escapements being so interconnected that they operate alternately. The form shown is a hand camera having a pistol-type grip and a disc shutter. The main spring has two sections 11, 12 in series, and is wound up by a knob 15 at the end of the main spindle 14. The body of the camera consists of a box 26 having a partition 27 which divides off the lower part 26a containing the gearing (Fig. 3) from the upper part 26b containing the film (Fig. 2). This passes from a supply spool 28 over guide rollers and through a gate aperture 33 to a take-up spool 29 via a feed sprocket 35. The primary gear wheel 24 is mounted on a spindle 14 just inside compartment 26a, and carries above it the single-toothed first escapement wheel 37 which controls film wind and setting the shutter. Gear wheel 24 also meshes with a train of gears which drives the feed sprocket 35, and, through a slipping clutch, the take-up spool 29. Just above wheel 37 is mounted a secondary spring 43, one end being secured to said wheel and the other end to a second single-toothed escapement wheel 44 which is free on spindle 14. Wheel 44 carries a bevel gear 45 which meshes with another bevel gear 46 mounted on a shaft 47 carrying the shutter at its other end. The shutter comprises two blades 48, 49, of resin-impregnated paper, blade 48 being fast on shaft 47, and blade 49 being angularly adjustable in relation thereto, so that the gap constituted by a notch in one overlapping a notch in the other can be varied. Blade 49 has several holes near its centre, and can be rotated by means of an externally extending sleeve 53 so that any of these holes can engage a pin 51 on the other blade. Two rocking escapement levers 58, 59 are pivoted one below the other on a common pin 61, corresponding respectively to the escapement wheels 37, 44. The levers are rocked by forked portions which engage with eccentric cams 62, 63. Each cam is carried by a pinion meshing with a toothed wheel, which can be rotated by a pawl and ratchet arrangement. Fig. 3 shows the pinion 64, toothed Wheel 65, ratchet and pawl 66, 67 for the upper cam 62. The pawls are pivoted in a yoke 68 engaged by a spring-loaded lever 69. The lever is operated by a press button 71, and the arrangement is such that movement of the yoke 68 in one direction (by pressing button 71) operates one escapement, and movement of the yoke in the other direction (by releasing button 71) operates the other excapement. To operate the camera, button 71 is pressed, which rocks the upper level 59 to release upper escapement wheel 44, so enabling the shutter to operate and make an exposure under the action of the secondary spring 43. (This has been initially tensioned by pressing button 71 before the film has been threaded into position.) On releasing button 71, lever 69 is returned by its spring-loading, rocking the lower lever 58 to release the lower escapement wheel 37, so allowing the energy in the tensioned main spring to wind on the film and re-tension the secondary spring 43 ready for the next exposure.