| 摘要 |
PROBLEM TO BE SOLVED: To provide a perfecting sheet offset printer scarcely causing a printing fault having a reduced machine-size at a first printing speed by alternately connecting a plurality of front surface printing units to a plurality of rear surface printing units via impression cylinders for constituting the respective units in a horizontal direction. SOLUTION: A sheet P is delivered from a feeder board 2 directly to an impression cylinder 12a of a first rear surface printing unit 6a via a swinging unit 3a, and printed on its rear surface with a first color. Then, the sheet P is delivered to an impression cylinder 11a of a first front surface printing unit 5a, and printed on its front surface with the first color. Thereafter, similarly, the sheet P is alternately printed on both the front and rear surfaces with second to fourth colors. Since rotation of an impression cylinder 11D is reverse to rotation of a delivery chain 22 with a gripper, the sheet P in which printing of the fourth color is finished is delivered directly to a chain 22 with a gripper, and delivered onto a delivery base 23. Accordingly, its structure is simplified that much corresponding to no transfer cylinder and no delivery cylinder, thereby shortening a printer length. |
