Automatic document feeder

Abstract

A switch is located near a pair of register rollers for feeding a document sheet toward a platen glass. A pair of document-feeding rollers are located near a platen glass. When the switch detects the rear edge of the document sheet being fed by the register rollers, it generates a signal. Upon receipt of this signal, the document-feeding rollers rotate, thus feeding the sheet for a prescribed distance and placing it at a predetermined position on the platen glass. The image on the sheet, thus positioned, is copied. An upper roller and a lower roller contacting each other are arranged at the exit side of the register rollers. The document sheets are braked as they pass, one after another, through the gap between the upper and lower rollers and are fed at the same speed, thus reducing their speeds to one and the same speed in spite of their different inertias. Hence, the switch detects the rear edges of the sheets at regular intevals, and the document-feeding rollers feed each document sheet, exactly for a prescribed distance, thereby placing the sheet at the predetermined position on the platen glass.