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:
Aug. 19, 1997
Filed:
Aug. 22, 1995
Shusuke Akazaki, Wako, JP;
Kotaro Miyashita, Wako, JP;
Ken Ogawa, Wako, JP;
Yoshihisa Hara, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio control system for an internal combustion engine having at least one catalytic converter arranged in the exhaust passage, comprises an ECU which changes air intake characteristics of the engine, based on operating conditions of the engine, and a plurality of exhaust gas component concentration sensors including at least upstream and downstream exhaust gas component concentration sensors arranged in the exhaust passage at respective locations upstream and downstream of the at least one catalytic converter. The air-fuel ratio of an air-fuel mixture to be supplied to the engine is controlled to a desired air-fuel ratio in a feedback manner responsive to an output from the upstream exhaust gas component concentration sensor. A feedback control parameter for use in the air-fuel ratio feedback control is calculated based on an output from the downstream exhaust gas component concentration sensor. The updating rate of the feedback control parameter is changed when the feedback control parameter is calculated, according to the air intake characteristics of the engine.