| 摘要 |
PROBLEM TO BE SOLVED: To enhance printing quality by making the tensions of a raw sheet before and after reversal same by controlling a variable synchronizing motor so as to make the rotational speed of a tension roller synchronous to that of the plate cylinder of a rear printing part and making a nip roller and a shaft movable in the direction approaching the tension roller and separating therefrom. SOLUTION: The rotation of a variable synchronizing motor 7 rotationally driving a tension roller 5 allowing a raw sheet A to take a U-turn through a transmission mechanism 6 is controlled by a control part 8 utilizing a microcomputer so as to make the rotational peripheral speed of the tension roller 5 synchronous to that of the plate cylinder 2A of a rear printing part. The nip shaft 10A supporting the nip roller 10 made of an elastic material provided in opposed relation to the tension roller 5 so as to leave a gap 9 on a machine frame in a freely rotatable manner is moved in the direction approaching the tension roller 5 and separating therefrom by a moving means. Therefore, the tension of the raw sheet is stabilized to prevent the shift of patterns. |
