PURPOSE: To ensure and ease the loading of a transcribing paper bundle by making a bottom plate one flat state in the opened condition of a paper supply tray, and a U-shapedly bent state with a large radius of curvature in the closed condition of the paper supply tray.

CONSTITUTION: When a rear tray 3 is moved so as to be a closed condition, a rack 4 and a pinion 5 are engaged each other, and the pinion 5 and a pulley 6 are rotated in a counterclockwise direction to wind a wire 7. When the diameter of the pulley 6 and the position of a relay pulley 8 are suitably set, the rear end is pulled in the oblique-upper forward direction and the rear part is bent upward in a bottom plate 10, and in the closed condition where the tray 3 completely overlapped a front tray 1, the plate 10 is made the U-shape state where the rear part is bent upward. When the tray 3 is pulled out so that a paper supply tray is made from a closed condition to an opened condition, the pinion 5 and the pulley 6 are rotated in a clockwise direction with a rack 4, and the wire 7 is wound out to make the plate 10 a flat state. And the rear end of a transcribing paper bundle is made untouchable to the front part upper surface of the bundle with a transcribing paper rear end receiving member 9 provided.