Patent ID: 8454013

Claim:
A sheet take-out apparatus comprising: a take-out unit adapted to take out a plurality of sheets in a stacked state one by one on a conveying route; a separation unit adapted to shift and separate overlapping sheets taken out by the take-out unit on the conveying route as a preceding sheet and a succeeding sheet, the separation unit being arranged downstream from the take-out unit; an overlapping detector adapted to detect overlapping sheets which have not been separated by the separation unit; and a re-separation unit adapted to re-separate the overlapping sheets detected by the overlapping detector, the re-separation unit including a drawing roller and a second pinch roller positioned downstream from the separation unit to draw out the sheet from the separation unit and a first conveying roller and a first pinch roller positioned downstream from the drawing roller and the second pinch roller, the first conveying roller and the first pinch roller configured to receive a front end of the preceding sheet and convey the preceding sheet, the drawing roller and the second pinch roller configured to decelerate their rotational speed while clamping the rear end of the succeeding sheet, wherein the overlapping detector is configured to detect the overlapping sheets which are clamped and restricted by a nip between the drawing roller and the second pinch roller, the overlapping detector including: a first sensor arranged to detect the sheets immediately after the nip of the drawing roller and the second pinch roller along the conveying direction of the sheets; a second sensor arranged to detect the sheets at a position away from the first sensor along a downstream side of the conveying direction, the distance between the first and second sensors exceeding the length of a longest sheet to be processed; a controller configured to judge 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 a third sensor on the downstream side of the first sensor and upstream side of the second sensor along the conveying direction, and when the third sensor detects passing of the rear end of the preceding sheet in the conveying direction, is adapted to return the rotational speed of the drawing roller and the second pinch roller from the deceleration.