PURPOSE: To realize an easy mechanism for shifting copy paper by using a pinch roll provided with a spiral groove for moving a paper sideways in the case where a roll supporting shaft is reversely rotated, so that the copy paper is shifted from a side surface to which a copying machine is opposed in the middle of both-side copying.

CONSTITUTION: This machine is provided with a shifting mechanism 90 set in the copying machine and moving the copy paper in the middle of facing to the tray 56 backward with respect to the front part of the copying machine so as to change the position of the copying paper fed from the tray 56 and so as to be matched. The mechanism 90 is constituted of a pair of pinch rolls 91 and 92. The pair of pinch rolls 91 and 92 moves the copy paper to the back of the copying machine, so that the copy paper can be matched by matching devices 82, 84 and 86 in the case where the copy paper passes by a corona generating device 30 for transferring next. Thus, the structure is made simple, and the paper can be easily handled.