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:
Jan. 02, 2001
Filed:
Jun. 03, 1999
Yoshiro Noda, Gifu, JP;
Toshihiko Aoyama, Aichi, JP;
NGK Spark Plug Co, Ltd., Aichi, JP;
Abstract
A ceramic heater with a specified ratio of electric resistance for the heat generating portion and the lead portion of a heat generating resistor is provided. The ceramic heater has a ceramic substrate comprising alumina as a main ingredient and a heat generating resistor composed only of tungsten, or a heat generating resistor comprising at least one of 3 to 30% by weight of alumina and 10 to 40% by weight of rhenium, and at least one of tungsten and molybdenum. Particularly, the ratio of the electric resistance can be controlled and the adhesion of ceramic substrates for sandwiching the heat generating resistor can be improved, for example, by means of disposing slits to the lead portion and/or changing ingredients constituting the lead portion. The ceramic heater is capable of reaching a predetermined temperature in a short time, has high adhesion between the heat generating resistor and ceramic substrates and excellent durability and can be used in an oxygen sensor.