Sheet transporting cylinder, and corresponding transport device, printing press and use of said cylinder

Abstract

A transporting cylinder ( 54 ) for a flat substrate, including a cylindrical base body ( 70 ) that has a cylindrical base body surface ( 74 ) having a first material and that has openings ( 82 ) leading out onto the cylindrical surface. The transporting cylinder ( 54 ) includes a sleeve ( 72 ) arranged on the cylindrical surface ( 74 ), the covering element having a plurality of through-holes ( 92 ) aligned with at least some of the openings ( 82 ). The sleeve ( 72 ) has an outer covering surface ( 88 ) made from a second material. The outer surface ( 88 ) has a surface energy lower than the surface energy of the first material.

1 - 13 . (canceled) 
     
     
         14 . A transporting cylinder for a flat substrate comprising:
 a cylindrical base body having a cylindrical surface having a first material having a first material surface energy and a plurality of openings leading out onto the cylindrical surface;   a covering element arranged on the cylindrical base body surface, the covering element having a plurality of through-holes aligned with at least some of the openings, the covering element having an outer covering surface, the outer covering surface being made from a second material, different from the first material, and in that the outer covering surface has a surface energy lower than the first material surface energy.   
     
     
         15 . The transporting cylinder according to  claim 14  wherein the outer covering surface is made of an ink repelling material. 
     
     
         16 . The transporting cylinder according to  claim 14  wherein the second material comprises polytetrafluorethylene or silicone. 
     
     
         17 . The transporting cylinder according to  claim 14  wherein the through-holes are rounded at their junction with the outer covering surface. 
     
     
         18 . The transporting cylinder according to  claim 14  wherein the through-holes have, in the non-stressed state of the covering element, a diameter smaller than a diameter of the openings. 
     
     
         19 . The transporting cylinder according to  claim 14  wherein the covering element comprises a first axial section provided with the through-holes and a second solid axial section, without the through-holes or other through-holes, and the second solid axial section covers an axial portion of the base body provided with openings. 
     
     
         20 . The transporting cylinder according to  claim 14  wherein the covering element is a cylindrical sleeve and the outer covering surface is a surface of the sleeve. 
     
     
         21 . An assembly comprising a transporting cylinder according to  claim 14 , the covering element having a first thickness, and further comprising a spare covering element, the spare covering element having a second thickness, different from the first thickness. 
     
     
         22 . A device for transporting a flat product comprising:
 a transporting cylinder according to  claim 14  for the flat product; and   a vacuum device adapted to create a vacuum;   at least part of the plurality of openings being connected to the vacuum device.   
     
     
         23 . The transporting device according to  claim 22  wherein the transporting device is a device for cutting a strip into sheets, and further comprises a cutting cylinder, the transporting cylinder being an impression cylinder of the cutting cylinder. 
     
     
         24 . A printing press comprising:
 a printing unit adapted to print on a strip of paper; and   a transporting device according to  claim 22 .   
     
     
         25 . A method for operating a transporting cylinder according to  claim 14  comprising the following successive steps:
 transporting a predetermined quantity of paper using the transporting cylinder; 
 removing the covering element from the base body; and 
 placing a non-worn covering element on the base body. 
 
     
     
         26 . A method for operating an assembly according to  claim 21  comprising the following successive steps:
 transporting a predetermined quantity of paper using the transporting cylinder; 
 removing the covering element from the base body; and 
 adjusting a traction exerted on the paper by placing the spare covering element on the base body.