Patent GB-204116-A (GB)
Title: Improvements in film printing machines
IPC: G03B27/08
Filed: 1922-06-20
Abstract: 204,116. Wade. H., (PathÚ Exchange, Inc.). June 20, 1922. Printing-apparatus.-In film printing apparatus, in which the negative and positive films pass through the gate on opposite sides of a separating plate and across a printing aperture where they are pressed into contact for printing, means, actuated by a manually operable lever, are provided to release the pressure on the films, which thereupon automatically separate, and to shift back the film actuating mechanism so that it engages only with the negative film, causing this to continue to move through the gate while the positive film remains stationary, the release of the said lever causing the film actuating mechanism to return to its original position thereby actuating both films. Thus, such parts of the negative film as may be desired are omitted from the positive. As shown, the negative film C and the positive film B pass simultaneously on either side of a plate G provided with a printing aperture G‹ and slots g<9>, Fig. 10. A superimposed door F has two pressure plates F<1>, F<3>. which may be provided with pressure rollers. The pressure plate F<3> presses the two films together in the aperture G‹ and the plate F@ presses the positive film on the panel G<4>, the required pressure being exerted by fingers f<5>, f<6>, Fig. 1, fast on rods f<3>, f<4>, which have arms f<1>, f<2> connected by a tension spring F<2>, Fig. 7. A continually driven shaft K<1>, Fig. 4, has (1) a slidably keyed cam M which moves the plate H, carrying the teeth h engaging the film driving perforations, in and out of engagement, (2) a keyed cam which reciprocates the plate H and (3) a pinion K. This pinion engages a gear wheel J fixed to a clutch member J<1> free on a shaft I<2> on which is mounted the positive film feeding wheel P, a keyed pulley I', and a slidably keyed clutch member J<2>, Pivoted at N<1> is a lever N to which is pivoted a rod N<3>. The lever N is connected to the members J<2>, M so that it can slide them on the shafts I<2> and K<1> respectively. During normal running the apparatus is as shown in Fig. 4, the shaft K<1> operating the mechanism to give intermittent motion to the two films, and the member J<2> engaging the member J<1> so that the pinion K drives the feed roller P and the pulley I<1> which operates the positive rewinding pulley. When it is desired to omit a certain section of be negative film, the knob N'-on the rod' N<3> is pressed so that the clutch J<1>, J<2> is disengaged to stop the shaft P, and the end of the lever N presses a rod P into engagement with the lever f<1> so that the pressure on the plate F<3> is released and the two films, in contact in the aperture, G‹, separate. At the same time the lever N moves the cam M axially so that the teeth h in their " in " position engage only the driving perforations of the negative film while the positive film remains stationary. The movement of the negative film can be observed through a red glass in the pressure plate F<3>, and when the parts which are tobe omitted have passed, the rod N<3> is released and the printing operation continues.