Linear Ordering Problem

A sheet feeding system wherein, when a start signal for starting sheet feeding is given, a sheet tray is brought into contact with a first feed roller and at the same time the first feed roller is driven to rotate. When a first detection mechanism has detected the leading end of a sheet having reached between a second feed roller and a parting roller, the sheet tray is separated from the first feed roller and when the sheet is detected by the second detection mechanism, the second feed roller is stopped after a delay time that the leading end of the sheet contacts a stopper closing a sheet threading path for the sheet to be slightly looped, and the sheet threading path is opened upon the lapse of a predetermined time and the parting roller is then disengaged from the second feed roller.