摘要:
A printed sheet monitoring assembly utilizes a suction box with a planar lower suction surface to hold a printed sheet to be monitored in a crease-free manner. An area array image sensor is positioned beneath the suction box and is actuated by a trigger device to scan the printed sheet. The sheet grippers on an endless conveying chain are arranged on the chain to be in vertical alignment during scanning of the printed sheet.
摘要:
The rotary web-fed printing machine has three successively arranged printing units, namely one offset and two intaglio printing units which are all of a similar design to sheet-fed printing units and in which the cylinders (2, 3) forming the printing nip have a plurality of sectors separated by cylinder pits (2a, 3b). Each printing unit has, in front of the printing nip, a first paper-web store (29) and an intermittently controllable first draw-roller unit (30) and, after the printing nip, an intermittently controllable second draw-roller unit (31) and second paper-web store (32), the draw-roller units (30, 31) which have only one suction roller being controllable for the forward and backward movement of the web (P) by means of individually regulated drives (30a, 31a) and at the same time serving for the register check. In front of the first paper-web store (29) of the first printing unit (A), between the printing units within the portions limited by the respective paper-web stores and behind the second paper-web store of the last printing unit, the web (P) is moved uniformly by continuously driven draw-roller arrangements (27), whereas during the run through the printing nip the paper-web transport takes place in the pilgrim-step mode.