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. 11, 1997
Filed:
Nov. 30, 1995
Shinichi Abe, Aichi-gun, JP;
Toyota Jidosha Kabushiki Kaisha, Aichi, JP;
Abstract
An air-fuel ratio control device is for an internal combustion engine having a fuel injector and a catalytic converter, with an O.sub.2 storage ability, arranged in an exhaust passage. The device comprises a first air-fuel ratio detector for detecting an air-fuel ratio in an exhaust gas upstream of the catalytic converter and a second air-fuel ratio detector for detecting an air-fuel ratio in exhaust gas downstream of the catalytic converter. The device controls an amount of injected fuel on the basis of an output of the first air-fuel ratio detector, and corrects a standard output of the first air-fuel ratio detector corresponding to the stoichiometric air-fuel ratio by a correction value determined on the basis of a difference between an air-fuel ratio detected by the second air-fuel ratio detector and the stoichiometric air-fuel ratio. Moreover, the device changes the correction value such that the lower a current O.sub.2 storage ability is, determined on the basis of a variable which varies in accordance with the current O.sub.2 storage ability, the smaller said correction value becomes.