Method of and an apparatus for aligning sheets advancing in an

Abstract

An elongated array of partially overlapping sheets advances to a printing machine and, prior to entering the same the individual sheets of the array, one after another, are aligned both along their front edges and along one of their lateral edges. This is accomplished by first displacing the respective sheet transversely of the array so that a lateral marginal portion adjacent to the one lateral edge becomes exposed, after or during alignment along the front edge, and by subsequently engaging the exposed lateral marginal portion of the respective sheet and displacing the latter a further distance only transversely of the array into a position in which the one lateral edge is aligned. Subsequently to the alignment along both of the above-mentioned edges, the respective sheet may be partially returned by a given distance prior or during feeding of the sheet into the printing machine. The apparatus includes a suction belt conveyor which displaces the respective sheet the first distance, and an engaging device which displaces the sheet the second distance, while the return of the sheet may be accomplished by an in-feed gripper of the printing machine. The engaging device may include a suction rail reciprocating transversely of the array, or a roller mechanically cooperating with a gripping rail to engage the exposed lateral marginal portion of the sheet and to displace the latter by the second distance.