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.

Date of Patent:
Feb. 10, 2004

Filed:

May. 29, 2002
Applicant:
Inventors:

Nobuhide Kato, Ama-Gun, JP;

Kunihiko Nakagaki, Nagoya, JP;

Satoshi Nishikawa, Chita, JP;

Assignee:

NGK Insulators, Ltd., Nagoya, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N 2/7407 ;
U.S. Cl.
CPC ...
G01N 2/7407 ;
Abstract

A NOx sensor for measuring NOx concentration including a main pumping cell and a detecting electrode, the main pumping cell-including an electrode having no decomposing/reducing ability for NOx or a low decomposing/reducing ability for NOx, to be used to control oxygen concentration in a measurement gas to have a predetermined value at which NO is not substantially decomposable, and the detecting electrode having a certain decomposing/reducing ability for NOx or a high decomposing/reducing ability for NOx, to be used so that NOx is decomposed to measure the NOx concentration by measuring an amount of oxygen produced during this process, wherein a cermet electrode composed of a Pt—Rh alloy and a ceramic component is used as the detecting electrode. Accordingly, it is possible to suppress the oxidation of Rh and the reconversion into the metal contained in the detecting electrode, stabilize the impedance, and stabilize the sensitivity to NOx.


Find Patent Forward Citations

Loading…