Wound roll offset machine with changeable printing format

Abstract

The invention relates to an offset press; the empty space of a printing cylinder is taken as an area where the printing breadth is adjusted, namely, the arc surface start line of the printing cylinder is a printing start zero line, and the arc surface end line of the printing cylinder is a printing tail line; furthermore, a blanket cylinder and the printing cylinder can be rotated independently; the blanket cylinder and the printing cylinder are driven to rotate by a servo motor respectively; the servo motor is controlled by a PLC for working. When the printing breadth is required to be changed, the printing cylinder is required to be rotated in an initial state, namely the printing tail line of the printing cylinder moves forwards to the tail where the graph / text is required to be printed; meanwhile, the arc surface of the printing cylinder corresponding to the head of the blanket cylinder generates a new printing start line and the effective printing distance between the blanket cylinder and the printing cylinder is the arc length from the new printing start line of the printing cylinder to the printing tail line of the printing cylinder.

Description

technical field [0001] The invention relates to an offset printing machine, in particular to an offset printing machine capable of changing the printing width. Background technique [0002] There are two types of offset printing machines: sheet-fed offset printing machine and web offset printing machine. There is an application number ZL200610039009.9 (publication number CN101037033Y) Chinese invention patent "Focus Four-Color Offset Press", which discloses such a sheet-fed four-color offset press, which includes a paper feeding mechanism, four printing units , a paper transfer cylinder, a paper receiving mechanism, and a frame. The four printing units are respectively arranged on the frame, and a paper transfer cylinder is respectively arranged between two adjacent printing units. The described paper transfer mechanism adopts non-circular gears A mechanism for adjusting the paper feeding speed; the printing unit is composed of an ink system, a printing plate cylinder, a ru...

AI Technical Summary

Problems solved by technology

Since the size of the printing cylinder group of this kind of web offset printing machine is fixed, the format of each printing is also fixed. If the printed matter is smaller than the maximum format, there will be many blank spaces in the format of the paper, which is a waste of paper. Space, paper utilization is low, which increases printing costs

If this type of web offset printing machine needs to change the printing format, it is necessary to change the printing format by replacing the printing plate cylinder, rubber cylinder and impression cylinder, which is too expensive

Especially for the label printing industry, since there are various labels on the market, ranging from large to small, if each type of label needs to have a printing cylinder set corresponding to it, the printing cost of the label will increase greatly. For small and medium-sized Existing offset printing machines are not suitable for batch label printing

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