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. 23, 2003
Filed:
Oct. 16, 2001
Nissan Motor Co., Ltd., Yokohama, JP;
Abstract
A controller ( ) computes the oxygen storage amount of the catalyst ( ) separately as a high-speed component and a low speed component in accordance with actual characteristic. A target air-fuel ratio of an engine ( ) is computed so that the oxygen storage amount is a predetermined target amount, and air-fuel ratio control of the engine ( ) is performed. The oxygen storage amount is computed using an storage/release rate set according to the exhaust air-fuel ratio and catalyst temperature, etc. In this way, the oxygen storage amount of the catalyst can be precisely computed regardless of the variation in the storage/release rate which accompanies a catalyst temperature variation, and the real oxygen storage amount can therefore be controlled with a higher level of precision.