Patent ID: 6543760
Filing Date: 2003-04-08
Classification: B65H

Abstract:
A device for feeding sheets one by one from a stack of sheets to a transportation device for transporting the sheet to a process station, the device comprising a first low-pressure chamber with an integrated feeding table which supports the stack of sheets, a number of separately driven shafts which are positioned perpendicular to a direction of transportation and are arranged in the low-pressure chamber essentially equidistantly spaced from one another and which each carry a plurality of wheels with friction lining, which protrude through associated openings in the feeding table, and a sheet support which is arranged essentially vertically above the feeding table and at a distance from the feeding table which is somewhat larger than a thickness of a sheet, wherein the device further comprises a second low-pressure chamber, between the first low-pressure chamber and the transportation device, having an integrated feeding table which forms an extension of the feeding table of the first low-pressure chamber, and a plurality of separately driven shafts are arranged in the second low-pressure chamber at essentially a same distance from one another and having a distance between adjacent shafts in the first low-pressure chamber and in the second low-pressure chamber, respectively, each shaft in the second low-pressure chamber carrying a plurality of wheels with friction lining, which protrude through associated openings in the feeding table of the second low-pressure chamber, at least one sensor being arranged between the second low-pressure chamber and the transportation device, the sensor being adapted to detect a position of a front edge of the fed sheet and to send signals to a control unit, and wherein the control unit is adapted to correct, if necessary, the position of the front edge of the sheet by controlling drive motors of the shafts.