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:
Nov. 06, 1990
Filed:
Nov. 16, 1989
Kazuo Kojima, Yokohama, JP;
Nissan Motor Company Limited, Yokohama, JP;
Abstract
An air-fuel ratio feedback control system for an automotive internal combustion engine equipped with an evaporative emission control device having an activated charcoal cansiter for absorbing fuel vapor from a fuel tank. The air-fuel ratio feedback control system is operated as follows: The air-fuel ratio of air-fuel mixture to be inducted into the engine is detected in accordance with a component of exhaust gas discharged from the engine. An air-fuel ratio feedback correction coefficient is set in accordance with the air-fuel ratio in such a manner as to be modified by a feedback control constant in response to the state of the air-fuel ratio relative to stoichiomeric value. The amount of fuel to be supplied to the engine is corrected with the air-fuel ratio feedback correction coefficient. Additionally, the feedback control constant is enlarged for a predetermined time when the evaporative emission control device is so operated that the fuel vapor stored in the activated charcoal canister is sucked into the engine, thereby improving follow-up ability of air-fuel ratio feedback control thus to improve exhaust emission control and driveability of the engine.