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:
Jan. 23, 2001
Filed:
Nov. 08, 1999
Joseph J. Bella, Wheaton, IL (US);
Steven L. Bivens, Kankakee, IL (US);
Lisa E. Chisholm, Prospect Heights, IL (US);
Gary R. Little, St. Charles, IL (US);
Illinois Tool Works Inc., Glenview, IL (US);
Abstract
The air damper includes a housing with cylindrical walls and a piston assembly reciprocating therein. The piston assembly includes an interior surface against which a seal abuts. The interior surface is textured in a grained pattern so that interstices are formed between the seal and the interior surface thereby forming an effective air passageway for damping. A cylindrical spacer spaces the interior surface from a retainer and the seal is engaged around the cylindrical spacer and between the retainer and the interior surface. An alternative embodiment inserts textile material through a damping orifice in order to vary the rate of damping.