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:
Nov. 24, 1992
Filed:
Nov. 15, 1991
Applicant:
Inventors:
Nobuaki Kayanuma, Gotenba, JP;
Masayuki Sawano, Sunto, JP;
Assignee:
Toyota Jidosha Kabushiki Kaisha, Aichi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01N / ;
U.S. Cl.
CPC ...
60276 ; 60277 ; 60285 ; 731181 ;
Abstract
An apparatus for determining a deterioration of a condition of a three-way catalyst arranged in an exhaust passage of an internal combustion engine, comprising an upstream O.sub.2 sensor arranged in the exhaust passage upstream of the catalyst and a downstream O.sub.2 sensor arranged in the exhaust passage downstream of the catalyst. An air-fuel ratio feedback correction amount is calculated in accordance with the output of the upstream O.sub.2 sensor, and the rate of change of the air-fuel ratio feedback correction amount is decreased when it is determined that the condition of the catalyst has deteriorated.