David T Polkinghorne

US Patent:

6364247, Apr 2, 2002

Filed:

Jan 31, 2000

Appl. No.:

09/494819

Inventors:

David T. Polkinghorne - Barrington IL 60010

International Classification:

G03B 152

US Classification:

24261511, 24236411, 242908, 205 93, 205109, 205114

Abstract:

The present invention provides a pneumatic flotation device for use in a continuous web processing system for continuously processing paper and other flexible materials and a method of making the pneumatic flotation device. The pneumatic floatation device replaces the rolls, idlers and air bars currently used in continuous processing systems. The pneumatic floatation device includes a microporous sheet attached to a suitable pneumatic support structure. The microporous sheet has a smooth exterior layer with regularly spaced pores that enables air to pass therethrough. The interior layer of the sheet is an open structure metal fabric that enables air to move freely along two axes of the sheet parallel to the exterior layer while in contact with the pneumatic support structure. In one preferred embodiment, the pneumatic support structure includes a rigid tube and an airflow device in fluid communication with the microporous sheet. All of the pneumatic support structure or a portion thereof may be covered with the microporous sheet forming an air boundary layer.