Air guide box for the dryer section of a paper making machine

Abstract

An air guide box for the dryer section of a paper making machine is arranged as generally between two succeeding drying cylinders and along a continuous support band or belt which supports the associated paper web to be dried; the air guide box has an end of generally wedge-like configuration which extends at least some distance into the gore-like space as exists in the region where the support band or belt runs onto the next drying cylinder; a first gap exists generally between a first wall of the guide box and the running support band or belt while a second gap exists as between a second wall of the guide box and the juxtaposed surface of such next drying cylinder. In order to guide the paper web along the support band or belt in order to assure proper contact: (a) on the inflow side, an air wipe-off or barrier apparatus is provided as at the guide box; (b) the first gap preferably diverges from the first wall as the first gap more nearly approaches the gore-like space; (c) the guide box is connected to a blast air supply which, preferably, is directed through an opening and into the second gap as to have a flow direction generally opposite to the direction of rotation of such next drying cylinder; and (d) preferably the first and second gaps are interconnected by a passage with such interconnecting passage being situated as to occur before the air blast opening when viewed or considered in the direction of rotation of such next drying cylinder.