GB1079171A - Improvements in or relating to duplicating processes - Google Patents

Abstract

1,079,171. Printing-apparatus. LLOYD PATON (SYSTEMS) Ltd. April 28, 1964 [Jan. 29, 1963], No. 3585/63. Heading B6C. A rotary duplicating machine comprises a printing cylinder having a portion of its surface of greater radius than the remainder and an impression roller which co-operates only with said portion at the line of printing. Spirit duplicators, Fig. 1 depicts a spirit duplicating machine including a printing cylinder 11 supporting a plastics pad 18 carrying a master 12, an impression roller 14 adapted to co-operate with the master 12 with a pressure adjustable by means of eccentrics 15, and a dampening pad 20 arranged to contact a paper web 22 and movable in timed sequence on rotation of the printing cylinder by a lever and roller device 23. 24. A platform 25 supports the web while it is being dampened with spirit. The masters may be fed to the nip in web form. Printing surfaces.-The pad 18 may alternatively be of metal, paper or cardboard and may have a self-adhesive backing or may be secured to the cylinder magnetically, by clips, pressstuds, spigots and sockets, or partial vacuum with one edge 19 in register with a datum line on the cylinder. The master is preferably secured to the pad 18 by a radially movable clip, Fig. 2 (not shown) having a jaw which engages a cut-away portion of the cylinder, said portion acting as the datum line, but may alternatively be positioned by clips, press-studs, snap-fasteners, adhesives, magnets, or partial vacuum means. The cylinder 11 may be cut away to facilitate inspection. In the embodiment of Fig. 5 a used store 40 and a new store 41 are provided, new masters and pads or new masters alone being stored in the store 41 and used pads and masters or used masters being ejected by a mechanism 42 into the store 41. A guide 43 prevents undue radial movement of the master on the pad. Stencil duplicators.-Fig. 4 shows an embodiment in which a cylinder is provided with perforations 36 and carries a thin impervious portion 38 which covers unwanted perforations, and a porous pad 37 supporting a stencil 39. Ink is inserted either into the cylinder or into the pad 37. The embodiment of Fig. 5 may be converted into a stencil duplicator, each stencil being provided with an ink filled pad.