Abstract: Recirculating feeders, operatively connected to a copier, can operate in collate or noncollate modes, i.e. produce collated or noncollated output copies. In the noncollate mode of operation, the recirculating feeder acts in a similar manner as a conventional document feeder. When an operator places only a single original document in the recirculating feeder and, mistakenly, the feeder and copier are in the collate mode of operation, the apparatus will automatically determine that there is only a single original document in the recirculating feeder and transfer the mode of operation from collate to noncollate.

Abstract: A collating document feeder with a multiple-feed detector for use on a convenience copier. The feeder circulates the document sheets one-after-another for presentation to the copier once, and recirculates the sheets one-after-another for presentation to the copier again, thereby to present the sheets for copying in an order that facilitates collation of the final copies. The multiple-feed detector compares the number of presentations during circulation with the number of presentations during recirculation, to detect the occurrence of multiple feeds. The number of presentations can be determined, for example, by counting the number of exposures, or the number of times document sheets are fed.