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. 25, 1998
Filed:
Feb. 21, 1997
Eisuke Kimura, Saitama, JP;
Toru Yano, Saitama, JP;
Kohei Hanada, Saitama, JP;
Yusuke Tatara, Saitama, JP;
Takashi Haga, Saitama, JP;
Masanori Hayashi, Saitama, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio control system for an internal combustion engine having a fuel injection valve for each cylinder and an electronic air control valve (EACV) for controlling intake air bypassing the engine throttle valve. When the target air-fuel ratio is switched over from a rich value to a lean value, the amounts of fuel injected into the cylinders, for example, #1, #2, #3 and #4 cylinders are controlled so that they are sequentially decreased at predetermined intervals, and the EACV is controlled to be opened stepwise. This causes a decrease in engine torque generated by the switching-over of the target air-fuel ratio to be offset by an increase in engine torque generated by an increase in amount of air drawn, thereby preventing the generation of a torque shock. At this time, the target opening degree of the EACV is corrected based on the magnitude of the interval and the magnitude of a loading of the internal combustion engine, thereby further effectively preventing the generation of the torque shock.