| 摘要 |
PURPOSE:To permit effective utilization of the whole peripheral surface of an impression cylinder as the supporting surface for a printing paper and to enable printing on the whole surface of the printing paper by providing an air passage which has communicating portions which communicate with the outer peripheral surface of the impression cylinder, a printing paper attracting mechanism connected to the above passage and a printing paper releasing mechanism. CONSTITUTION:Adjacent to the outer surface of an impression cylinder 11 a printing paper cassette 49 for storing and piling of preprinted sheets of paper P is provided. And, inside of the impression cylinder 11, an air passage 21 which has communicating portions 12 that communicate with the outer peripheral surface of the impression cylinder 11 is provided. When the communicating portion 12 faces the front edge of a sheet of printing paper P in the bottom of the paper cassette 49, the air in the air passage 21 is sucked through the communicating portion 12 and the sheet of paper 12 is attracted to the outer surface of the cylinder 11 and at the same time, following the rotation of the cylinder 11, as the communicating portion 12 turns around from the position where the sheet was attracted to a position as far away to exceed the length of the sheet P, the attraction of the sheet of the paper finishes. The printing paper attracting mechanism 32 which has the function as a state above is provided. Further, a printing paper release mechanism 46 is provided as follows; when the operation of the printing paper attracting mechanism 32 is suspended, air is supplied to the air passage 21 through the communicating portion 12 and the sheet of paper P is released from the outer peripheral surface of the impression cylinder 11. |
