GB923750A - Improvements in or relating to rotary duplicating machines - Google Patents

Abstract

923,750. Duplicating-machines. W. RITZERFELD, and G. RITZERFELD. Sept. 15, 1961 [Oct. 14, 1960 (2)], No. 33177/61. Class 100 (2). A rotary duplicating-machine for printing lines or sections from a printing master sheet 3 on to a copy sheet 23 in immediate succession or closer spacing than the spacing of the lines or sections on the sheet 3 comprises a printing drum 2 carrying the master sheet 3, a counterpressure roller 13 movable towards or away from the drum 2 for effecting printing, said roller either being mounted by bearings on an eccentrically mounted shaft 11, Fig. 1, or being carried on a centrally mounted shaft 11, Fig. 4, carried in cross-guides, one of which, 43, extends generally radially of the drum 2 and the other 34 has a cam path causing movement of the shaft 11 in the guide 43, and means for either rotating the eccentrically mounted shaft or moving the guide 34 relative to the shaft 11 in timed relation with the arrival of a required line of printing between the drum and the roller. In the embodiment of Fig. 1, the roller 13, carried on an eccentrically mounted shaft 11 is movable towards the drum 2 under the action of electromagnets 20 which are energized by the contacts K1-K14 of a rotary switch 5. A contact arm 4 of the switch 5 carries a brush 27 which engages the contacts as the arm rotates synchronously with the drum 2 and completes a circuit with those to which a potential has been applied by a keyboard 21. The electromagnets 20 are thus energized and cause the armatures 19 to turn the shaft 11 through rods 16 and levers 14 each time a selected line on the sheet 3 corresponding to a contact on the switch 4 passes through the line of printing A-B. In the embodiment of Fig. 4 the members 16 carry cam slots 34 therein and a centrally mounted shaft 11 carrying the roller 13 is supported by the slots 34 and further slots 43 in guide members 44. In the embodiments of Figs. 3 and 6 (not shown) the electromagnets of Figs. 1 and 4 are replaced by a series of displaceable cams movable into the plane of a follower roller connected to a member 16.