PURPOSE: To easily perform restoration work of trouble such as a jam by inserting and pulling out a paper guide in the vertical direction along the guide groove of a guide rail provided in a mechanical frame and moving a frame for fixation in the front and rear directions in the position where the paper guide is inserted and fixing the paper guide.

CONSTITUTION: When an outside guide 1c is held by a hand and moved in the direction D, the outside guide 1c is turned around a slide bush 2 and opened. When the outside guide 1c is closed, it is moved in the reverse direction D and a projection 1f provided in the side part of an inside guide 1d is inserted into a hole 1e provided in the side part of the outside guide 1c and the outside guide 1c is fixed to the inside guide 1d. When such a paper guide 1 as this is fitted, a frame 7 is separated from a guide rail 4 through a pinion and a rack by lever operation. Thereafter the slide bush 2 is inserted into the guide groove 4a of the guide rail 4 and operation is performed so as to push down the paper guide 1 in place.