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:
Feb. 21, 1995
Filed:
Oct. 12, 1993
Katsuhiko Kawai, Kariya, JP;
Hisayo Douta, Kariya, JP;
Niopondenso Co., Ltd., Kariya, JP;
Abstract
An air-fuel ratio control system for an internal combustion engine uses a dynamic model which is set as an approximation to a controlled object. The controlled object covers an operation sequence from a fuel injection valve to an air-fuel ratio sensor which is provided downstream of a catalytic converter for detecting an actual air-fuel ratio based on the exhaust gas downstream of the catalytic converter. The system derives a fuel injection amount to be fed to the engine by performing a state-feedback control in such a manner as to control the actual air-fuel ratio to a target air-fuel ratio. The system performs the state-feedback control using, as state variables, current and past input and output data relative to the dynamic model. Accordingly, the actual air-fuel ratio monitored on the downstream-side of the catalytic converter is controlled to the target air-fuel ratio without delay by directly deriving the fuel injection amount using the state-feedback control.