The guide device uses nozzles (18) connectable to a suction or blow air source. The nozzles swivel in the guide face about axes running across the sheet conveyor direction so that the air stream emerging from the nozzles can be directed both in the direction of movement of the printed material and opposite same. The nozzles can be set at any angular position in the angular area between the two opposite end positions. Cylindrical tubes (16) are mounted on the side of the guide face remote from the sheet conveyor path and parallel to same. The nozzles are fitted on the tube and the tubes can rotate about their axis and be fixed in any angular position.
