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:
Mar. 08, 2016
Filed:
Jan. 30, 2013
Takeshi Genko, Toyota, JP;
Takeshi Genko, Toyota, JP;
Toyota Jidosha Kabushiki Kaisha, Toyota-shi, JP;
Abstract
An air-fuel ratio imbalance determination apparatus for a multi-cylinder internal combustion engine includes an air-fuel ratio sensor with a catalyst layer disposed in an exhaust passage of the multi-cylinder internal combustion engine; and a control unit configured: to perform determination regarding an air-fuel ratio imbalance state among cylinders of the multi-cylinder internal combustion engine based on an amount of change per unit time in an air-fuel ratio detected by the air-fuel ratio sensor; to execute an air-fuel ratio enrichment control using an air-fuel ratio enrichment amount; and to correct a learned imbalance value when the air-fuel ratio enrichment amount is smaller than a predetermined determination threshold value in a case where an engine operation state is in an imbalance learning range during execution of the air-fuel ratio enrichment control.