Sheet feeding apparatus and automatic document feeder

摘要

An automatic document feeder (ADF) for feeding a document across a platen is attachable to different types of copying machines which have different copying speeds. The ADF has a detector for detecting the copying speed of the copy machine and a controller for adjusting the document feeding speed of the ADF to the copying speed of the copy machine. The controller also controls the feeding speed of the document at a standard speed in a condition which does not lower copying efficiency and at a higher speed in a condition which lowers copying efficiency. A condition which does not lower copying efficiency is feeding documents other than the last document from the platen. A condition which lowers copying efficiency is feeding the first document to the platen and ejection of the last document from the platen.