公开(公告)号：US4998658A

公开(公告)日：1991-03-12

申请号：US290208

申请日：1988-12-27

申请人： Joseph Distefano ,  Roger Haas ,  Mark Nestle ,  Fred D. Kelley

发明人： Joseph Distefano ,  Roger Haas ,  Mark Nestle ,  Fred D. Kelley

IPC分类号： B65H20/12 ,  B65H27/00

CPC分类号： B65H20/12 ,  B65H27/00 ,  B65H2404/136 ,  B65H2404/1362 ,  B65H2404/181

摘要： An unported vacuum drum has a system of closely spaced small grooves in the outer surface thereof and holes drilled in the drum provide communication between the grooves on the outer surface and a space on the interior of the drum. The interior drum can be connected to a source of vacuum for applying the vacuum through the holes to the grooves. In order to avoid defects that may occur in a web brought into contact with a drum, the outer surface of the drum is covered with a porous sleeve. The pores in the sleeve enable the vacuum to be applied from the grooves to the outer surface of the sleeve for holding the web onto the sleeve.