Patent ID: 8201823
Filing Date: 2012-06-19
Classification: B65H

Abstract:
1. A sheet feeding apparatus comprising: a sheet feeding unit including a pick roller, wherein the sheet feeding unit is configured to feed one sheet at a time from a stack of sheets into a structure, the one sheet being a first sheet that is a topmost sheet of a stack of sheets; a sheet stopping unit configured to stop feeding of a second sheet into the structure while the sheet feeding unit is feeding the first sheet into the structure; and a lifted-portion detector disposed above the first sheet across the pick roller, the lifted-portion detector configured to detect a lifted portion formed by the first sheet and the second sheet when the first sheet and the second sheet are stapled together, by detecting beam reflected by the lifted portion above the lifted-portion detector, wherein the lifted portion is a portion of the first sheet and the second sheet that gets lifted and moved to a position above the lifted-portion detector because the first sheet is being fed by the sheet feeding unit while the second sheet has been stopped by the sheet stopping unit; wherein the lifted-portion detector is configured to emit detecting signals upwards, the lifted-portion detector further configured to detect the detecting signals reflected by the lifted portion when the lifted portion moves to the position above the lifted-portion detector; and wherein the lifted-portion detector is configured to detect the stapled sheets by detecting the lifted portion and interrupt the feeding of the first sheet by the sheet feeding unit.