automatic document feeder (ADF)
An Automatic Document Feeder(ADF) is an electromechanical device used in scanners, copiers, fax machines, and multifunction devices to automatically feed and process documents. This device is also referred to as an automatic document changer (AVW).
In the automatic document feeder, a stack of documents is placed in the document feeder and a mechanism feeds the documents one by one, always after the previous one has been processed.
For documents printed on both sides, there are document feeders that can turn the document over and scan the front and back sides. Depending on the method, one speaks of Duplex Automatic Document Feeder (DADF) or Reverse Automatic Document Feeder (RADF).