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. 14, 2002
Filed:
Dec. 21, 1999
Katsumi Morohoshi, Kanagawa, JP;
Kouichi Nemoto, Kanagawa, JP;
Masashi Ito, Kanagawa, JP;
Takeshi Yamauchi, Kanagawa, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
A sound-absorbing duct structure for an intake system of an automotive internal combustion engine. The sound-absorbing duct structure comprises a duct defining thereinside a gas passage. A part of the duct is formed with a plurality of small holes. An expanded duct section is formed around the part of the duct. The expanded duct section defines therein an inside space which is in communication with the gas passage through the small holes. The inside space has a cross-sectional area larger than that of the gas passage. A sound-absorbing section is disposed in at least a part of the inside space of the first expanded duct section. The sound absorbing section includes a piezoelectric material exhibiting a piezoelectric effect, and an electrically conductive material in contact with the piezoelectric material.