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:
May. 01, 2001
Filed:
Jun. 08, 1999
Applicant:
Inventor:
Toshikatsu Takanohashi, Saitama, JP;
Assignee:
Honda Giken Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F01N 3/00 ;
U.S. Cl.
CPC ...
F01N 3/00 ;
Abstract
In accordance with an output of an oxygen concentration sensor,, an air-fuel ratio correction coefficient KO2 is periodically set to values respectively corresponding to a leaner air-fuel ratio and a richer air-fuel ratio with respect to a theoretical air-fuel ratio (steps S,to S,). Based on an output of an oxygen concentration sensor,, a NOx amount counter nNOx is counted up, and the amount of NOx absorbed by a NOx absorbent catalyst is estimated. When the value of the NOx amount counter nNOx reaches a preset value NSAT, an air-fuel ratio of an air-fuel mixture is set to be further richer than the richer air-fuel ratio.