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. 24, 2006
Filed:
Mar. 13, 2003
Shinji Yamaguchi, Ama-gun, JP;
Kazuhiro Nobori, Handa, JP;
Shinji Yamaguchi, Ama-gun, JP;
Kazuhiro Nobori, Handa, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
A ceramic heater is provided including a ceramic sintered body and a heat resistor embedded in the substrate, wherein a change in the temperature uniformity on the heating face is reduced. The heat resistor contains a metal comprising one or more metal elements selected from the group consisting of Group IVa, Group Va and Group VIa elements of the Periodic Table and a carbide of the metal. A ratio (Ic/Im) of a total strength (Ic) of main peak of the metal carbide to a total strength (Im) of main peak strength of the metal is not larger than 0.2. Alternatively, the ratio (Rb−Ra)/Ra is not larger than 30 percent, where 'Ra' is the resistance of the heat resistor before sintering and 'Rb' is the resistance of the heat resistor after sintering.