| 摘要 |
PURPOSE:To facilitate the change-over and to prevent occurrence of damage of a sheet, by providing a front guard member in the upstream one of a plurality of discharged sheet stacking devices arranged in parallel in the paper conveying direction so that the front guard member is made to rise upright and fall so as to select one of the discharged sheet stacking devices. CONSTITUTION:A sheet S which has been printed by multiple colors with the use of a plurality of printing units 2 only one of which is shown, is conveyed by way of a paper extracting cylinder 10 by means of a paper discharge chain 14 which is driven by a pair of right and left sprockets 11, and is then introduced into a first pile 21 or a second pile 22 in a paper discharge device 3. When a front guard plate 31 provided at the lower end of the upstream first pile 21 is raised upright, the sheet S abuts against the front guard plate 31 so that it drops onto a sheet stacking plate 25 in the first pile 21 and is stacked thereon. When the first pile 21 becomes full or when an unsatisfactorily printed sheet is detected, the front guard plate 31 is made to fall so that the sheet S is stored in the second pile 22. With this arrangement, it is possible to change over the piles without stopping the drive of the printing section, thereby it is possible to prevent occurrence of damage of a sheet due to restart. |
