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:
Feb. 04, 1997
Filed:
Feb. 16, 1995
Applicant:
Inventor:
Akira Uchikawa, Atsugi, JP;
Assignee:
Unisia Jecs Corporation, Atsugi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F01N / ;
U.S. Cl.
CPC ...
60274 ; 60284 ; 60285 ; 123674 ; 123691 ;
Abstract
In a device having air-fuel ratio sensors upstream and downstream of an exhaust gas purifying catalytic converter with learning carried out based on output values from the downstream air-fuel ratio sensor, independent learning is carried out depending on whether the catalytic converter is active or not. The air-fuel ratio is then controlled based on the output value of the first air-fuel ratio sensor, the output value of the second air-fuel ratio sensor and the learned value. As a result leaning accuracy is increased and air-fuel ratio control performance enhanced.