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:
Sep. 28, 1993
Filed:
Mar. 30, 1992
Hideki Yamada, Hatsukaichi, JP;
Hisashi Zaima, Higashihiroshima, JP;
Shigeki Yamashita, Hiroshima, JP;
Kazuo Tanaka, Hiroshima, JP;
Mazda Motor Corporation, Hiroshima, JP;
Abstract
An exhaust purification system has an upstream exhaust gas sensor and a downstream exhaust gas sensor disposed downstream of a catalytic device. Each sensor detects an oxygen concentration in exhaust gases and provides an output which inverts between a lean state, representative of a lean air/fuel ratio, and a rich state, representative of a rich air/fuel ratio, according to oxygen concentrations. The upstream exhaust sensor is determined to have deteriorated when an output from the upstream exhaust sensor is kept in a predetermined correlation with an output from the downstream exhaust sensor while the output from the downstream exhaust sensor remains the same.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile