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:
Oct. 07, 2008
Filed:
Sep. 03, 2003
Yuji Yasui, Wako, JP;
Akihiro Shinjo, Wako, JP;
Tatsuhito Esaki, Wako, JP;
Naoto Fujimura, Wako, JP;
Yuji Yasui, Wako, JP;
Akihiro Shinjo, Wako, JP;
Tatsuhito Esaki, Wako, JP;
Naoto Fujimura, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Minato-Ku, Tokyo, JP;
Abstract
An air fuel ratio controller for an internal combustion engine includes an exhaust gas sensor, an identifier and a control unit. The exhaust gas sensor detects oxygen concentration of exhaust gas. The identifier calculates model parameters for a model of a controlled object based on the output of the exhaust gas sensor. The controlled object includes an exhaust system of the engine. The control unit is configured to use the model parameters to control the air-fuel ratio so that the output of the exhaust gas sensor converges to a desired value, and to stop the identifier from calculating the model parameters during and immediately after the engine operation with a lean air-fuel ratio. The calculation of the model parameters may be also stopped during and immediately after fuel-cut operation that stops fuel supply to the engine. Such a stop of the calculation of the model parameters reduces the emission of undesired substances contained in exhaust gas when the engine shifts from lean operation to stoichiometric/rich operation.