Automatic original document feeder for electrophotographic copier

Abstract

A document feeder for advancing original documents to the exposure platen of an electrophotographic copier which is capable of operating in either a semiautomatic or fully automatic mode. In the semiautomatic mode, an original to be copied is manually inserted face up into an inlet where it is engaged by the semiautomatic transport assembly inverted and advances to a proper position for copying. After exposure the document is again inverted and guided into a receiving tray overlying the platen. In the automatic mode of operation, a second tray normally maintained in an inoperative position is swung down to a position at which its feed end is adjacent the feeder inlet. Documents to be copied are placed face up as a stack in the second tray, and feed rollers carried by the tray are actuated to advance documents individually from the stack to the inlet. In a preferred embodiment, a driven feed roller is disposed below the retarding roller at a fixed spacing therefrom to feed sheets from the bottom of the stack so that the sheets are collected in the stacking tray in their original order. In the same embodiment, a guide strip having fingers extending between the feed roller and reduced-diameter portions of the retarding roller is resiliently urged into engagement with the feed roller to press the sheet being fed firmly against the roller to ensure reliable feed regardless of sheet thickness.