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. 29, 1996
Filed:
Aug. 22, 1995
Yusuke Hasegawa, Wako, JP;
Yoichi Nishimura, Wako, JP;
Isao Komoriya, Wako, JP;
Shusuke Akazaki, Wako, JP;
Eisuke Kimura, Wako, JP;
Honda Giken Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
An air-fuel ratio estimator for estimating air-fuel ratio of an air and fuel mixture supplied to an internal combustion engine from an output of an air-fuel ratio sensor. In the estimator, detection response lag time of said air-fuel ratio sensor is approximated as a first-order lag time system to produce state equation from said first-order lag time system. The state equation is discretized for a period delta T to obtain a discretized state equation. A transfer function is calculated from the discretized state equation and is then an inverse transfer function is calculated from said transfer function. And correction coefficient of said inverse transfer function is determined and multiplying with inverse transfer function to the sensor output estimate an air-fuel ratio of an air and fuel mixture supplied to the engine. The correction coefficient is predetermined with respect to engine speed and is made zero at or below a predetermined engine speed.