GB211719A - Improvements in or relating to printing machines - Google Patents

Abstract

211,719. Centore, E. March 6, 1923. Printing with flexible printing-surfaces.-A de. vice for printing designs on fragile articles of irregular shape, such as plates, of the kind comprising an article carrier with a flexible diaphragm for supporting the article and a type carrier with a flexible diaphragm carrying the design, the diaphragms being subjected to partial vacuum when positioning the article and to air pressure for making the impression, is provided with means for automatically centering the type carrier relatively to the article carrier, such means preferably consisting of coned members. Platen machines.-The hollow member a contains the article carrier c shaped on its upper surface to conform with the shape of the plate &c. to be printed. The upper surface of the plate carrier c communicates by passages d with a central passage e and nozzle f, which is connected to a vacuum and compressed air apparatus. Over the member c is stretched a rubber diaphragm f secured to the ring i held in position by a flange l on an outer ring k. The diaphragm j<1> to which the types or designs are secured is similarly fixed to the type carrier o by a ring i' held in position by a ring k<1>. Interfitting conical rims are formed on the edges of the rings k, k<1> accurately to centre the carriers c, o when they are brought together. The type carrier has a central opening p p and nozzle r communicating with a vacuum and air pressure apparatus. In operation, both carriers are first moved apart and subjected to vacuum action, by which the diaphragm f is drawn down on to the carrier c enabling the plate to be placed thereon, and the design carrying diaphragm j<1> is held against movement on the carrier o whilst the inking rollers are run over it. Escape of air between the diaphragms and their carriers is facilitated by radial grooves d<1> on the carrier c and concentric grooves on the carrier o, air vents n, u being also provided round the edges of the members k, k<1>. The carriers are then brought together and subjected to air pressure, which forces the diaphragm j<1> into contact with the inside of the plate to make the impression. Risk of breakage of the plate during the impression is obviated by the action of the air pressure under the diaphragm j. The rings i, i<1> on the two carriers are interchangeable. Printing-surfaces.-The design on the diaphragm j<1>, Fig. 3, is formed of portions v of vulcanized rubber stuck on strips x of spongy rubber secured by rubber solution to the diaphragm. To permit escape of air the strips x are perforated at x<1> and fluted strips y are stuck radially round the periphery.