JPH0476110B

PURPOSE:To detect quickly defective carrying due to such as jam and to reduce running cost by detecting whether paper whose surface copying is completed is assuredly stored in a normal stock position or not at double-surface copying operation. CONSTITUTION:An intermediate tray 27 consisting of a tray plate 27a, matching plate 27b, and a stopper 27c constitutes a paper stock part. Said tray plate 27a and stopper 27c are fixed, and when paper is set up on the tray plate 27, the tip part of the paper is engaged with the stopper 27c and the position of the carrying direction is regulated to store the paper. When the paper 52 is carried into the tray 27, the machining plate 27b is positioned on the abutted state upon the end part of the paper side. Thereby, the side of the front end part of the paper is inserted between a are flecting plate 41 fixed on the matching plate 27b and an optical sensor 42. After the passage of a fixed period from the detection of paper by the optical sensor 42, the matching plate 27b is moved in the direction of an abutting releasing position where the matching plate 27b release the abutting upon the paper in the H direction. After the matching plate 27b and the reflecting plate 41 have temporally released the engage ment with the paper 52 and have reached the abutting releasing positions, the matching plate 27b moves in the I direction.