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:
Jul. 27, 1999
Filed:
Jan. 07, 1997
C Raymond Cheng, Madison, WI (US);
Jason D McIntosh, Savage, MN (US);
Michael T Zuroski, Sun Prairie, WI (US);
Larry J Eriksson, Madison, WI (US);
Nelson Industries, Inc., Stoughton, WI (US);
Abstract
An acoustic resonator (20) has a resonator cavity (22) with a resonator port (24) for communicating with an exhaust flow passage (26) conducting acoustic waves therethrough. Adjustable port structure varies acoustic impedance of the port by various combinations including translation to vary area along an arcuate surface, translation between discrete areas, translation to cumulatively open port area, multiple translation, multiple ports, rotational area change, and rotational length change. Adaptive control may be provided. A combined passive and active acoustic system may also be provided.