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:
Jan. 27, 2009
Filed:
Oct. 30, 2007
Applicants:
Keiji Wakahara, Inazawa, JP;
Takeshi Fujimoto, Obu, JP;
Inventors:
Keiji Wakahara, Inazawa, JP;
Takeshi Fujimoto, Obu, JP;
Assignee:
Denso Corporation, , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B60T 7/12 (2006.01); F02D 41/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
An engine control apparatus feedback-controls a mixture air-fuel ratio of air-fuel mixture supplied to each cylinder of the engine based on an exhaust air-fuel ratio detected by an air-fuel ratio sensor. The control apparatus further calculates an exhaust air-fuel ratio change rate at every predetermined interval and integrates an absolute value of the exhaust air-fuel ratio change rate. The control apparatus determines an abnormality in any one of engine cylinders when an integration value of the exhaust air-fuel ratio change rate exceeds a predetermined reference value.