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:
May. 01, 2012
Filed:
Mar. 24, 2008
Yoshinobu Goto, Nagoya, JP;
Yoshinobu Goto, Nagoya, JP;
NGK Insulators, Ltd., Nagoya, JP;
Abstract
A first heating element and a second heating element, which are capable of individually controlling temperatures thereof, are embedded in a ceramic base. Each of the first heating element and the second heating element is formed into a spiral shape so as not to contact the other from a central portion of the base to an outer circumferential portion thereof in substantially the same plane parallel to a heating surface of the base. One of the first and second heating elements includes a high heating density portion on the central portion side of the base, and a low heating density portion on the peripheral portion side of the base, and the other of the first and second heating elements includes a low heating density portion on the central portion side of the base, and a high heating density portion on the peripheral portion side of the base.