| 摘要 |
A description is given of an apparatus for selectively covering suction holes in a circumferential surface of a suction roller for transporting flat pieces of material of a given format, wherein the apparatus comprises a flexible ribbed sheet (1), which has a multitude of raised ribs (2) and grooves (3) respectively running between the ribs, wherein suction passageways (4) that pass through the ribbed sheet are arranged in the ribs. The object is to develop this apparatus in such a way that pieces of flat material of a wide variety of formats can be transported and peeled off from the circumference of the roller with lowest possible costs. To achieve this object, it is proposed to make the arrangement of the suction passageways in the ribbed sheet correspond substantially to the arrangement of the suction holes in the circumferential surface of the suction roller and additionally provide the apparatus with a flexible masking sheet (5) with suction openings (6) passing through it, which are arranged in accordance with the format of the pieces of flat material to be transported, so that when the masking sheet and the ribbed sheet are arranged lying one on top of the other on the circumferential surface of the suction roller a suction effect is only produced in those regions of the circumferential surface in which it is desired, in accordance with the format of the pieces of flat material. |
