GB1036974A - Automatic shutter cocking mechanism for cameras - Google Patents

Abstract

1,036,974. Shutter-setting mechanisms. GRAFLEX INC. Feb. 9, 1965, No. 5595/65. Heading G2A. When the shutter is released, the blade-actuating ring, as it runs down, causes an electric motor to be energized which drives a member to retension the shutter. As shown, the four shutter blades 27 are actuated each by a respective pinion 24, the pinions being driven simultaneously by a master gear 31 which underlies and is integral with a toothed ring 32. Above ring 32 is a spur gear 36, rotatable on a central cylindrical bearing 34 (Fig. 2, not shown). In the space between ring 32 and gear 36 are two helical springs 37, each fixed at one end to posts 38 on ring 32, and at the other end to posts 39 on gear 36. These springs, when stretched tension the shutter blades, this being the position in Fig.1 (not shown). Ring 32 is maintained in this position by a latch lever 46 having a dog 47 which latches in front of one of the teeth on ring 32, lever 46 being maintained in this position by a spring 49. When the shutter release 53 is pressed, a shoulder portion 56 moves away from abutment against the end of lever 46, so that the lever can no longer restrain the ring 32, and the lever is pushed anticlockwise as ring 32 (and hence master gear 31) is rotated clockwise by the tensioning springs, thus operating the shutter. At the same time, another of the teeth on ring 32 engages against a dog 92 of a slidable brake plate 90, moving it to the right against the action of a spring 88. Through a system of levers, this pivots a blade spring 108 (Fig. 1, not shown) to actuate a microswitch 105 which energizes an electric motor. This drives a gear 76 which meshes with a gear 75, the latter operating, through a further train of gears, the spur gear 36. This is rotated clockwise relative to wheel 32 (which is stationary), so that the springs 37 are tensioned once more, thus cocking the shutter again. The invention is of utility in cameras in which the shutter is released by remote control, since the shutter is then re-tensioned automatically, without requiring manual re-wind.