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:
May. 07, 2002
Filed:
Nov. 21, 2000
Matthias Alex, Heilbronn, DE;
Helmut Spannbauer, Moeglingen, DE;
Filterwerk Mann & Hummel GmbH, Ludwigshafen, DE;
Abstract
An air induction device ( ) for an internal combustion engine including an air filter housing ( ) with an open induction tube ( ) leading away from it and a supplementary induction tube ( ) having a closing element, preferably in the area of its end opening ( ). The closing element may take the form of a rotary flap ( ) and is actuated depending on engine speed. The housing ( ) and the induction tubes ( ) are configured in geometrical terms in such a way that at low engine rotational speeds, the housing ( ) and the open induction tube ( ) form a Helmholtz resonator, while the closed supplementary induction tube ( ) forms a quarter-wave tube leading from the housing ( ). At higher engine rotational speeds, the supplementary induction tube ( ) is opened, and the overall length of the supplementary induction tube ( ) is adapted so that at the higher speeds, it forms a Helmholtz resonator with the air filter housing ( ) and the open induction tube ( ).