| 摘要 |
PROBLEM TO BE SOLVED: To align the vertical direction of printed matters in the surface and the back surface of the printing paper sheets by moving a printing paper sheet from a first reverse carrying passage to a second reverse carrying passage with a movement energizing means, and furthermore, moving the printing paper sheet from the second reverse carrying passage to a third reverse carrying passage, and controlling the operation of each structure. SOLUTION: A printing paper sheet is carried to an end of the downstream of a first reverse carrying passage 3. The printing paper sheet is carried along a second reverse carrying passage 4 by a first movement energizing means 6 and each carrying roller 46 or the like. The printing paper sheet is carried along a third reverse carrying passage 5 by a second movement energizing means 7 and a carrying roller 51, and the printing paper sheet is carried onto a main carrying passage 2 again. At this stage, paper sheet carrying direction is changed from left to right, and the surface and the back surface are turned over. Tip direction and rear end direction of the paper sheet are aligned on the main carrying passage 2 at the time of surface printing, and while carried in the condition that the surface and the back surface thereof are turned over, and printing of the back surface is performed at the same timing with the printing of the surface on the basis of the detection of a printing starting sensor 23. |
