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:
Jul. 11, 2000
Filed:
Aug. 31, 1998
Yukihiro Yamashita, Kariya, JP;
Shujiro Morinaga, Kariya, JP;
Hisashi Iida, Kariya, JP;
Hidenobu Muto, Obu, JP;
Denso Corporation, Kariya, JP;
Abstract
An air-fuel ratio feedback control has an air-fuel ratio sensor and an oxygen sensor at an upstream side and a downstream side of a catalytic converter. A CPU feedback controls an air-fuel ratio detected by the air-fuel ratio sensor to a target air-fuel ratio, with a feedback gain being varied with an output of the oxygen sensor. The CPU further estimates an air-fuel ratio response speed based on a ratio between an exhaust gas flow amount and a capacity of the catalyst and determines a rate of deterioration of the catalyst. The CPU varies further the feedback gain based on the estimated response speed and the determined rate of deterioration.