Patent GB-190226470-A (GB)
Title: Improvements in Automatic Magic Lantern Apparatus
Inventor: BENTZON MALCOLM
Filed: 1902-12-01
Granted: 1903-11-05
Abstract: 26,470. Bentzon, M. Dec. 1. Magic-lantern apparatus.-Fig. 1 shows an elevation in section of coinfreed apparatus for the automatic optical projection of a series of lantern slides. Fig. 2 shows a horizontal section, and Figs. 3 and 4 sections on the lines 3-3 and 4-4 of Fig. 1 respectively. The lantern slides i are placed in spaces g<3> on a tray g running on rails g<2> disposed by the side of a lantern b with condenser d and projection lens c. In front of the latter, a mirror f is fixed to deflect the light upon a screen e arranged in front of the casing. Each slide is pushed,in turn, into the space i<2> for projection, after which it is returned to the magazine. The apparatus for effecting this consists of two arms or fingers k, k' adapted to slide on a cross-bar k'. These fingers are reciprocated by a lever l pivoted at l<1> and acted upon by cams m, m' on a shaft m<2> A cam on the same shaft acts on a lever o<3>, which, through a link o<4> and lever o<5>, operates a pawl o<1>, which engages with and operates a sprocket-wheel o on the end of a screw h, which, engaging with a nut h' on the tray g, feeds the latter along the rails g<2> to bring each slide in succession opposite the space i' in the lantern. The operation of the shaft m' is effected by a motor n driving, through belt gearing, a pulley n<4> on a shaft n<5>, which, through worm gear, drives the shaft m'. The operation of the apparatus by the insertion of a coin is effected as follows : - The coin drops into a bucket r', and lowers it by its weight into the position shown in broken lines. This action raises a pawl r<5>, which normally engages with and locks a disc on the shaft of the starting-lever. When the starting- handle is operated, it, through a crank u, rod u<1>, bell-crank lever u', rod u<3>, and arm t pivoted at t<0>, throws a clutch n<8>, n<9> into operation. The clutch is held in action against a spring t<9> by a pawl t<2>, which is subsequently automatioally released upon the completion of the exhibition of the series of slides determined upon. The series of slides selected is brought into position for exhibition by the operation of a handle p, which is connected by epicyclic gearing p<6>, p<11>, p<7> to a sprocket-wheel p<3> which drives, through a belt p<4>, the screw shaft h engaging with the nut h<1> on the tray g. The handle p can, however, only be operated when the coinbucket lever r‹ is depressed, as shown by Fig. 4. When this is the case, a stop r on a lever r<1> encounters and prevents the rotation of the spindle p<10> of the wheel p<11>. The handle p is always operated before the handle r<8>, as the operation of the latter first raises and discharges the coin-bucket and thus makes the subsequent operation of the handle p impossible. To prevent the starting of the apparatus until the slide in the magazine is in exact registration with the slide carrier of the lantern, a disc s with a notched periphery is driven from the shaft h. A spring pawl s<2> engaging with these notches is arranged so that its tail s' locks the starting-handle except when it registers with a notch. The tray g, after the slides have been exhibited, is automatically returned to its initial position. In one modification, the motor is replaced by hand-gear operated by an outside oscillating handle ; in another, specially for advertising purposes, the coin-freed starting and indicating mechanism is replaced by automatic clock gear.