Patent GB-972794-A (GB)
Title: Improvements in or relating to rotary duplicating machines,methods of making printedcopies thereby and printing master sheets for use therewith
IPC: B41L11/00
Filed: 1963-07-11
Abstract: 972,794. Printing apparatus. W. RITZERFELD, and G. RITZERFELD. July 11, 1963 [Aug. 24, 1962; Sept. 13, 1962], No. 27475/63. Heading B6C. In an automatically operable rotary line-byline selective printing machine having inking and moistening roller trains the printing plate comprises a metallic printing master sheet upon which the image is inscribed in relief. The master sheet 5, Fig. 2, has an inscribed image 201-effected by a typewriter or by hand-and, at its trailing end, an iron strip 6. The sheet is of aluminium and has raster points 202, Fig. 4, the side to be inscribed having a resilient paint coating 203. The raster points are electrolytically, chemically or mechanically roughened at 204 and on inscription of the sheet the image 201 receives a fat coating 205 from a fat transfer sheet placed behind the master sheet during inscription so that the image 201 is rendered fat accepting and water repelling whereas at the image free regions the points 202 are water receiving and fat repelling owing to the roughening 204. The machine shown in Fig. 5 has a cylinder 1, on which the sheet 5 is clamped by a clamp 207, Fig. 6, at its leading edge and secured at its trailing edge by permanent magnets 7. Mounting is effected by placing the sheet-inscribed face uppermoston a plate 219 prior to actuating a manual lever 214. The inking mechanism 8 comprises a rockably mounted ink forme roller 13, transfer roller 15, a metering roller 16 and an ink transfer roller 25 the air gap between the rollers 16 and 25 being settable through the manual actuation of a setting screw 22. Ink is transferred from a rockably amounted container 28 to the roller 16 via a ductor roller 26 and an ink lifting rubber device 27 secured thereto. The drive to the inking mechanism includes intermeshing gear wheels and pinions and a magnetic tooth clutch 40. A diagrammatic development of the inking train is shown in Fig. 7 the rollers being reduced in a step-like manner towards both ends. The moistening mechanism, driven from the machine drive in a manner similar to the drive of the inking mechanism 8, comprises a trough 231, Figs. 5, 10, a ductor roller 236 and a moisture applying roller 246. The swinging movement of the roller 246 relative to the cylinder 1 is automatically effected by a set of cams 54 and a sensing roller 244 associated therewith. By means of a manual lever 253 the roller 244 may be blocked so that, according to requirements, the roller 246 may be rendered inoperative, for example when hectographic printing from a master sheet not requiring moistening or when mounting a fresh master. The setting of the inking and moistening mechanisms, including the control of the ink forme roller 13 and the moisture applying roller 246, is effected from a cam set 54 adjustably arranged on the shaft 2 of the cylinder 1. The cam set 54 is adjusted for the desired printing effect by a manually operable knob 62 operation of which moves a setting cam 58, Fig. 11, to an appropriate position. A swingingly mounted impression cylinder 91 co-operates with the cylinder 1, Fig. 8, the control of the swinging movement of this cylinder 91 being effected in known manner from control cams arranged on a shaft 92 these cams being subdivided in the form of a heading cam 93 and heading extension cams 94a and 95b of various effective lengths. For the carrying out of whole page duplication from the entire master sheet 5 a whole-page cam 96 is used. For printing of one, two or three or more lines, line cams 98a, 98b and 98c are provided. The drive of the shaft 92 derives from the machine drive through intermeshing toothed wheels 99, 100 and 101. Electric switches and magnets are used to automatically operate the various movements of the machine to effect the selective line-by-line printing the heading setting being effected in known manner through the hand actuation of a switching rod 129, Fig. 9. Line setting is effected through the operation of a pull rod 141 movement of which shifts the line cams 98a, 98b, 98c in the direction of the arrow shown in Fig. 9. Whilst being mounted on the cylinder 1 the printing master sheet is protected from contact with the moisture roller 246 and the inking roller 13 by respective protection plates 250 and 75.