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:
Dec. 03, 2002
Filed:
Dec. 06, 2000
Applicant:
Inventors:
Assignee:
Mitsubishi Jidosha Kogyo Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F01N 3/00 ;
U.S. Cl.
CPC ...
F01N 3/00 ;
Abstract
An NO sensor detects the concentration of NO released from an occlusion type NO catalyst into the atmosphere. Based on the output of the NO sensor a total NO discharge A is computed. When the total NO discharge A reaches an NO emission judgment amount A , corresponding to an NO emission judgment amount designated by NO emission regulations, before a distance traveled C reaches a predetermined distance traveled C , an exhaust air-fuel ratio is changed to a rich air-fuel ratio to release NO from the occlusion type NO catalyst efficiently. Then, the exhaust air-fuel ratio is changed to a stoichiometric air-fuel ratio to purify and reduce NO by a three-way catalyst function.