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:
Jun. 22, 2004
Filed:
Apr. 25, 2003
Sadamitsu Harada, Gifu, JP;
Katsuki Aoi, Aichi, JP;
Tomohiro Hirata, Aichi, JP;
Yasuo Ito, Aichi, JP;
NGK Spark Plug Co., Ltd., Aichi, JP;
Abstract
A knock sensor comprises a sensor body having a metallic shell including a cylindrical portion and a flange portion formed at an end of the cylindrical portion, an annular piezoelectric element fitted around the cylindrical portion and an annular weighting member fitted around the cylindrical portion to hold the piezoelectric element between the weighting member and the flange portion, and a resin-molded sensor casing arranged circumferentially around the sensor body. The resin-molded sensor casing includes a weighting portion located nearer to the weighting member than to the piezoelectric element with respect to an axial direction of the cylindrical portion, and at least the weighting portion of the resin-molded sensor casing is made of a resin containing at least one of metal powder and metal oxide powder and has a density of 2.0 g/cm or higher.