To prevent the occurrence of breakage at the joint part of pressure plates, irrespective of a long term use.

An original cover 50 is opened/closed with reference to an original platen for placing the original, and also, the cover is prepared for covering the original while keeping the original platen closed so as to bring the original in press contact with the original platen, and the cover 50 is provided with plural pressure plates 11 and 52 which are arranged in an opening/ closing direction and connected by a connecting means 20 so as to mutually tilt, and the cover is provided with rotation control means 55 and 56 on the pressure plates together with the connecting means, the rotation control means 55 and 56 are prepared for controlling the rotation of the pressure plates in a direction coming closer to the original platen after the surfaces 11e and 52e facing the original platen of the pressure plates are made nearly flat.