GB423802A - An improved device for the projection of moving advertising matter, announcements and the like - Google Patents

Abstract

423,802. Changing signs. MILLAR, H. E., 48, Andrew Street, Windsor, near Melbourne, Australia. Aug. 8, 1933, No. 22172. Convention date, Aug. 5, 1932. [Class 3 (i)] Optical-projection apparatus.-A disc transparency is so mounted as to be uniformly rotated through one revolution by a clockwork motor, and then automatically stopped till again manually actuated. Fig. 2 shows one form in which a disc carrier 5 comprises a grooved annulus rotated by a cord 10 passing over the motor pulley 11 and tensioned by a jockey pulley 14. The annulus 5 is journalled at 11<a> in laterally adjustable bearings, and carries a radial projection 23 having an opening 22 adapted to receive a removable slide 25. The transparency disc 9 is held to the annulus 5 by spring clips 15, and has the display matter arranged radially with one blank portion opposite the slide 25. On pulling away by hand a spring-pressed projection 28 from a slot 27 the carrier 5 is released and the motor started, rotating the disc 9 through one revolution, determined by the projection 28 snapping again into the slot 27 and also stopping the motor. The slide 25 may be changed by manual manipulation during the rotation of the disc 9, and the disc 9 may be changed during the stationary periods when the slide 25 is showing. Fig. 6 depicts a modification in which the display matter 49 is disposed circumferentially on the disc 9, the opening 50<a> being in a radius which is vertical when the opening is in the light beam. A disc support having both vertical and horizontal spindle adjustment may be used for accommodating both types of disc. The device may have its own optical lantern, or be readily attachable to a kinematographic projector, a gauze screen &c. being provided in the beam in the latter case to reduce the light and heat effects.