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. 13, 2007
Filed:
Aug. 17, 2005
Jan Krüger, Neuhausen, DE;
Frank Castor, Esslingen, DE;
Jan Krüger, Neuhausen, DE;
Frank Castor, Esslingen, DE;
J. Eberspeecher GmnH, , DE;
Abstract
An active exhaust muffler for an exhaust system of an internal combustion engine, having a housing through which a pipe system passes, the pipe system designed to be permeable for airborne sound in a first space, having an antisound generator which is arranged in a second space and antisound acting upon a third space through a wall opening during operation, the wall opening being provided in a partition that separates the second space from the third space, whereby airborne sound is transmitted from the first space to the third space through a sound outlet. To increase the lifetime of the antisound generator and thus the exhaust muffler, a labyrinth is provided in the third space, blocking a direct path between the sound outlet and the wall opening, and providing at least one indirect bypass for the propagation of airborne sound between the sound outlet and the wall opening.