GB170195A - Improvements in rotary lithographic printing machines for direct or offset printing - Google Patents

Abstract

170,195. Linotype & Machinery, Ltd., and Stern, C. L. Oct. 7, 1920. Rotary machines; offset machines. - A rotary lithographic printing-machine which can be used for printing (a) single side direct, (b) single side offset, (c) perfector offset, oi (d) two colour offset, is constructed with two printing-cylinders 1, 2, and an impression cylinder 3 of half the diameter of the cylinder 1, 2, the cylinder 1 being fitted with an offset surface 5, and with a plate surface or offset surface 4, and with inking and damping mechanisms 9, 8 for the surface 4 when a printing-plate is employed on 4. The cylinder 2 may have two printing-plates 6, 7 fitted, and is provided with damping-mechanisms 10, 12, and inking-mechanisms 11, 13 for printing different colours, the damping-mechanisms being arranged adjacent to each other as shown or, if desired, the damping-mechanism 12 may be between the inking-mechanisms 11, 13, or only one damping-mechanism may be employed. For printing in the manner (a) referred to above, a. printing-plate 4 is fitted to the cylinder 1 and sheets are fed to cylinder 3 at every alternate revolution, the mechanisms not required being rendered in-operative in known manner. For manner (b), an offset impression from plate 7 is transferred to the offset surface 5 which prints a sheet carried by cylinder 3. For manner (c), a printing-plate is fitted to the surface 4 and prints on an offset surface on cylinder 3, which then prints on the underside of a sheet while the surface 5 prints an offset impression from the plate 7 on the outside of the sheet. For manner (d), the grippers on the cylinder 3 are arranged to carry the sheet for two revolutions, at each of which an offset impression from the plates 6, 7 is printed by the offset surfaces 4 5.