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:
Feb. 03, 1987
Filed:
May. 03, 1984
Applicant:
Inventors:
Shinichi Yokoi, Aichi, JP;
Tsuneo Ito, Aichi, JP;
Assignee:
NGK Spark Plug Co., Ltd., Nagoya, JP;
Primary Examiner:
Int. Cl.
CPC ...
B24B / ;
U.S. Cl.
CPC ...
264 61 ; 264 67 ; 264325 ;
Abstract
A method of making a ceramic heater by preparing a heating coil having a circular cross-section and bending it into a U-shaped form. Lead wires are connected to the ends of the U-shaped coil; the coil is embedded in a ceramic powder to form a preform having a substantially rectangular cross-section. The preform is compacted under heat to reduce the length of the rectangular cross-section and deform the coil embedded therein into a coil having an oval cross-section. The preform is sintered to form a ceramic product having a substantially circular cross-section and then ground to form a product having a circular cross-section.