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. 13, 2012
Filed:
Mar. 27, 2009
Akihiro Muroguchi, Aichi, JP;
San Jae Lee, Aichi, JP;
Kenshin Kitoh, Aichi, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
A gas sensor for measuring NOx concentration in measurement gas based on sensor output depending on an amount of the detected oxygen includes an oxygen concentration control part for controlling oxygen concentration in the measurement gas. The oxygen concentration control part allows a control of oxygen concentration in the measurement gas to set at a designated value even after being mounted on an automobile, so that dependency of the sensor output with respect to oxygen concentration can be quantitatively detected. The sensor output for detecting NOx concentration is corrected by estimating an amount of a change accompanying the sensitivity degradation of the sensor output with respect to NOx concentration on the basis of a difference between oxygen output characteristics of the sensor output of an actually-used sensor and oxygen output characteristics of a sensor in the initial state, and correcting the sensor output in accordance with the amount of the change.