| 摘要 |
PURPOSE:To prevent the contamination and abrasion of a conveying belt for originals by prohibiting the exertion of the pressing force of pressing means for originals when there are no originals on an original placing surface thereby preventing the direct contact of the conveying belt with the original placing surface. CONSTITUTION:When an original advances between a full surface belt 15 and original glass 47, and comes to the position of a press roller 16, electricity is conducted to a plunger 55, and the roller 16 presses the original, thereby increasing conveying force. The conduction of electricity t the plunger 55 is accomplished by counting the number of clocks. Similarly, when the original comes to the positions of press rollers 17, 18, electricity is conducted to plungers 75, 58, thereby increasing the converying force successively. The device is so constituted that, when a sensor 12 for detecting preceding ends detects the succeeding end of the original, the number of clocks is counted and when the succeeding end of the original passes through the rollers 16, 17, 18, the conduction of electricity to the plungers 55, 57, 58 is turned off. If the conduction of electricity to the plungers 55, 57, 58 is constituted in such a way, the pressing forces are exerted upon the rollers 16, 17, 18 only when there is the original. |
