Patent attributes
A document feeding apparatus includes a first delivery roller delivering a document sheet discharged from a fixing unit, a second delivery roller discharging the document sheet to a paper delivery tray, a motor driving the second delivery roller, a lever installed at the downstream, or upstream, side of the first delivery roller out of a document sheet transporting pathway, which rotates at a predetermined angle when contacting the document sheet and returns to an original position when not contacting the document sheet, a sensor sensing a rotation time and a returning time of the lever, and a controller determining a double feeding or slipping state of the document sheet based on a signal transferred from the sensor regarding the rotation time and the returning time of the lever, and controlling the driving speed of the motor according to the determination result.