Patent GB-316388-A (GB)
Title: Improvements in machines for the production of kinematograph films
IPC: G03B33/00
Filed: 1928-06-21
Abstract: 316,388. Thornton, J. E. June 21, 1928. Rotary machines.-A machine for producing a series of positive images on one or both sides of a continuous strip of kinematograph or other film by photo-mechanical or imbibition printing, for example as described in Specifications 316,338 and 316,367, [both in Class 98 (ii), Photographic processes &c.], comprises (1) a series of pressure rolls carried by a fixed frame, a co-acting series of pressure rolls carried by a floating frame, means for pressing the floating rolls against the fixed rolls so that the films, as they are passed between the two sets of rolls, are pressed together - over a length corresponding to several picture spaces, and gearing for driving all the rolls without backlash at the same peripheral speed; (2) a pair of intergeared driven registering sprockets, near the entry to the rolls, for registering together two printing belts from which images are to be transferred to opposite sides of a blank film fed between the belts or supports; (3) a pair of intergeared driven delivery sprockets for the two printing belts, arranged near the point of delivery of the rolls; (4) means for applying ink, dye, &c. to the printing belts after emergence from and before re-entry between the rolls; (5) means for punching feed perforations in the positive film after printing in such a manner that any difference in length between the printing belts or temporary supports and the positive film is compensated for. Provision may also be made for drying, varnishing, or applying hardening, flexing &c. liquids to the film after printing &c., and the machine may be adapted for printing &c. series of images either on one or both sides of a single-width film or in parallel arrangement on one side of a double-width film. The rolls and sprockets are preferably driven at the same peripheral speed from one common drive. The machine is shown in Fig. 1 as applied to the printing on opposite sides of a blank film 1 drawn from a reel F of photo-mechanical or imbibition images from printing-belts 2, 3 each formed as an endless band. The belts are accurately registered by sprockets D<2>, D<3> spaced slightly apart above two sets of coacting pressure rolls A<1>, B<1> between which the film and belts are fed. The rolls A<1> are carried by a fixed frame A and the rolls B<1> by a frame B displaceable horizontally on bars b by weighted levers C. Sprockets G draw the belts 2, 3 from the rolls and pass them first through inking or dyeing baths H and thence over rollers H' and sprockets D back to the point of entry for the next printing operation. Weighted rollers d<1>, g maintain the belts in tight contact with the sprockets D, D<2>, D<3>, G. The pressure rolls, sprockets, and the rollers h in the baths H are all driven, preferably from a common drive shaft. On leaving the pressure rolls, the film 1 enters a perforating device J, preferably of the eccentric plunger type, associated with a fan J' for removing the perforated pieces. It is fed through this device by a pilot feed claw J<2> reciprocated by an eccentric j<4> driven from the main shaft and moved up and down to feed the film by lever and link mechanism j<3>, the feed stroke being adjusted initially to correspond to the spacing of the printed positive images.. Thence the film passes over a sprocket K to a bath K<1>, which applies to it hardening, flexing, or varnishing agents, and after traversing a drying chamber K<2> supplied with hot air via pipes k<1>, k<2> is finally wound on a reel K<3>. Guides and guide rollers are fitted at the top and bottom of the machine to prevent lateral displacement of the unperforated film during printing and perforating. Modifications are described in which (1) the registering sprockets D<2>, D<3> are in contact, with intermeshing teeth which engage the feed perforations of the printing belts, this construction being designed for use when the belts are wider than the blank films so that their feed perforations lie beyond the edges of the film ; (2) one printing belt only of single or double width is used for printing one or two parallel series of images on one side of a blank film of single or double width; (3) the rollers A', B' are carried on a number of separate shorter frames A, B; and (4) the roller frames A, B are horizontally disposed.