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:
Feb. 10, 1981
Filed:
Apr. 06, 1979
John C McNabney, Verona, WI (US);
Wehr Corporation, Milwaukee, WI (US);
Abstract
The invention provides an airflow control mechanism for use in an air duct for controlling airflow through the duct. The air flow control mechanism includes a frame positionable in the duct, and a plurality of blades supported by the frame and extending transversely to the direction of the air flow through the air duct. At least one of the blades is supported for pivotal movement about its longitudinal axis and has an elongated edge moveable toward and away from an elongated edge of another of the blades to restrict air flow through the duct. A fiber material strip is applied to at least one of those edges, the fiber material strip including a substrate bonded to that edge and a plurality of closely spaced fibers projecting transversely from the substrate, the fiber covering being functional to prevent the generation of a high frequency standing wave between the adjacent surfaces of the blade.