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. 20, 1993
Filed:
Jun. 29, 1992
Applicant:
Inventors:
Kiyoshi Kuronishi, Hiroshima, JP;
Kazunari Komatsu, Hiroshima, JP;
Naoyuki Noguchi, Hiroshima, JP;
Hirofumi Nishimura, Hiroshima, JP;
Assignee:
Mazda Motor Corporation, Hiroshima, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01N / ;
U.S. Cl.
CPC ...
60276 ; 60277 ; 60285 ; 123691 ; 123692 ;
Abstract
An exhaust system for an automobile engine having two groups of cylinders has a catalytic device. Deterioration of the catalytic device is detected based on an oxygen level in exhaust gas passed through the catalytic device. A feedback control of an air-fuel ratio is conducted for the cylinder groups all together, based on either of the air-fuel ratios determined, based on emission levels of exhaust gas discharged, for one of two of the groups of cylinders, only when a specific vehicle driving condition is detected.