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:
Oct. 20, 1998
Filed:
Jan. 07, 1997
Keijiro Iwao, Kanagawa-ken, JP;
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
A noise insulating wall structure comprises a pair of noise insulating plates which face each other so as to be apart from another and each of which has a plurality of through holes. The noise insulating plates are connected to each other by means of a plurality of cylindrical portions. Each of the cylindrical portions is divided into two half portions, each of which has an abutting portion on the end face thereof. At least one of the abutting portions of the two half portions has a plurality of notched portions, each establishing the communication between the inside and outside of the cylindrical portion. The air layer at the central portion in the cylindrical portion serves as an air mass to form a vibration system of one-degree of freedom. In addition, the outside air layers in the through holes serve as air masses and the inside air layer in the cylindrical portion serves as an air spring to form a vibration system of two-degrees of freedom. The frequency characteristic is designed to be easily adjusted by varying the number, size and shape of the notched portions.