Electrostatic copying machine comprising improved document scanning means

Abstract

A book type document is placed on a glass platen face down and scanned by a reciprocating optical system one or more times to produce one or more copies respectively. A retractable conveyor comprising an endless belt is moved onto the platen to automatically feed a sheet document inserted thereinto onto the platen for scanning. Where only one copy of a sheet document is required, the optical system is maintained stationary and the sheet document is fed by the conveyor over the platen at the proper speed, thus enabling rapid copying of a large number of sheet documents. The magnification is variable through adjustment of the positions of the elements of the optical system when held stationary and the speed of movement of the document by the conveyor. The conveyor feeds a sheet document onto the platen at high speed and the optical system is reciprocated to scan the document a plurality of times where a plurality of copies of the document are required.