GB755306A - Improvements relating to rotary letterpress two side or perfecting machines - Google Patents

Abstract

755,306. Rotary printing-machines. VEB DRUCKMASCHINENWERK VICTORIA. Sept. 24, 1954, No. 27669/54. Class 100 (2). Perfecting.-A rotary letter-press printing- machine for printing on both sides of sheets comprises two printing couples, each having an impression cylinder 4, 13, Fig. 1, and a printing cylinder 5, 14, the sheets being transferred from the first to the second printing couple by rotary transfer devices 6, 10 and interposed drums 9, 11. The transfer devices 6, 10, each comprise a shaft 7, Fig. 2, and spaced discs 8 which are adjustable in position so as to avoid contacting printed portions of the sheet, Grippers of the impression cylinder 4 pass the sheet to grippers on the transfer device 6, the printed side of the sheet then facing inwardly. The sheet then passes round drum 9 being held by grippers thereon and may be subjected to a blast of hot air from nozzles 12 to aid drying. Grippers on transfer device 10 then take the sheet and forward it to drum 11 which passes it to the second printing couple 13, 14, which prints on the other side. The sheets are delivered by a chain deliverer 15 of known kind. The transfer means comprising devices 6, 10 and drums 9, 11 bridge an opening in the frame which allows a carriage 17 to enter to bring a printing cylinder into position for mounting on the machine. Both printing cylinders 5 and 14 may be interchangeable with other cylinders so that one set may be made ready for printing during the printing operation on other set.