HOLD-DOWN CYLINDER OF SHEET-FED PRINTING PRESS Russian patent published in 2001 - IPC

FIELD: printing arts. SUBSTANCE: hold-down cylinder 1 designed for the sheet-fed printing press has at least one recess 3, in which sheet grippers 4 are so arranged that in their closed position they do not project from the envelope of the cylindrical peripheral surface of hold-down cylinder 1. Cylinder recess 3 is provided with cover 1 moved by means of actuating mechanism 9,10,11,12, the cover always takes the closed position completely closing cylinder recess 3 in case cylinder recess 3 passes by the printing slot, so that the hold-down cylinder with the closed continuous peripheral surface revolves around the cylinder printing the image. In the zone of feed of sheets to hold-down cylinder 1 and from it cover 7 controlled at revolving of the cylinder mainly by fixed control cam 11 opens so that grippers 4 may take their open position for taking the sheet or for its transfer. EFFECT: prevented effects and shortcomings in the process of printing associated with the presence of recesses in the cylinder. 5 cl, 2 dwg