Apparatus and method for printing on both sides of a continuous paper web

摘要

In a printing apparatus for performing a printing operation on both obverse and reverse surfaces of a continuous web paper with an ink jet printing machine, there is a construction having a first printing unit for printing on one surface of the continuous web paper and a second printing unit for printing on the other surface of the continuous web paper, in which the first printing unit and the second printing unit are arranged at an identical position in respective paths of travel of a first portion and a second portion of the continuous web paper as oriented in parallel to each other, as facing downwards and as shifted to each other in the direction perpendicular to directions in which the first portion and the second portion of the continuous web paper are traveling, and the path of travel of the first portion of the continuous web paper which is printed by the first printing unit and the path of travel of the second portion of the continuous web paper which is printed by the second printing unit are made continuous via a turning unit for turning the continuous web paper at a right angle twice therein. The apparatus may be consturcted to include a guide roller assembly on which the first and second portions of the continuous web paper travel in parallel to each other, the guide roller assembly being separately divided into a first guide roller for guiding the first portion of the continuous web paper and a second guide roller for guiding the second portion of the continuous web paper, the first and second guide rollers being rotatably supported by a common supporting shaft. <IMAGE>