Patent ID: 7537212

Claim:
A sheet take-out method comprising: taking out a plurality of sheets in a stacked state one-by-one on a conveying route; shifting and separating overlapping sheets, taken out in an overlapped state on the conveying route at the time of take-out as a preceding sheet and a succeeding sheet; detecting overlapping sheets that are not separated; and clamping and decelerating a rear end of the succeeding sheet detected in a conveying direction and re-separating the overlapping sheets, such that the clamping and decelerating is performed by a conveying roller and a first pinch roller which received a front end of the preceding sheet passing the separating in the conveying direction, and a drawing roller and a second pinch roller which decelerate their rotation speed from a predetermined speed in a state where rear end of the succeeding sheet is clamped by the drawing roller and the second pinch roller, wherein the overlap detecting detects the overlapping sheets which are clamped and restricted by a nip between the drawing roller and the second pinch roller, wherein the overlap detecting is performed by a first sensor to detect the sheets immediately after the nip between the drawing roller and the second pinch roller in the conveying direction of the sheets; a second sensor to detect the sheets at a position away from the first sensor on a downstream side in the conveying direction, the distance between the first and second sensors exceeding the length of a longest sheet, and judging an overlapping of the sheets if the second sensor detects a sheet while, at the same time, the first sensor detects a sheet and if there are no gaps between the rear end of the preceding sheet and the front end of the succeeding sheet between the first and second sensors, and wherein the judging includes counting a gap between the sheets by, when the first sensor detects that the rear end of a sheet in the conveying direction pass the first sensor, counting up the gap count, and when the second sensor detects that the rear end of the sheet in the conveying direction pass the second sensor counting down the gap count, and when the first and second sensors detect simultaneously the sheets and a value of the gap count is zero, judging that overlapping of sheets occurs.