The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 17, 1992
Filed:
Mar. 20, 1990
Pertti Heikkila, Kyro, FI;
Valmet Paper Machinery Inc., , FI;
Abstract
A method for use in web drying apparatus, such as a drying section of a coating or paper machine which includes drying cylinders against the outer mantles of which a web to be dried is pressed in direct contact, and wherein the web is carried from one drying cylinder to the next supported on a wire which passes from a drying cylinder over an intermediate leading cyclinder where the web is carried on the outer side of the wire out of direct contact with an outer mantle of the leading cylinder, and then to the next drying cylinder, comprises the steps of maintaining a negative pressure in a pocket space defined between a pair of successive drying cylinders and the web-supporting wire for suctioning the web into contact with the wire as it runs from one drying cylinder to the intermediate leading cylinder and from the intermediate leading cylinder to the next drying cylinder, and providing the leading cylinder with a perforated outer mantle and maintaining a negative pressure within the interior of the outer mantle, to thereby render it a suction cylinder for suctioning the web into contact with the wire as the wire travels over the suction cylinder. Apparatus for use in the method includes a pocket chamber for enclosing the pocket and apparatus for maintaining negative pressures in the enclosed pocket space and interior of the leading cylinder.