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. 09, 2000
Filed:
Dec. 12, 1995
Applicant:
Inventors:
Takahiro Suzuki, Nagoya, JP;
Yukihiko Ito, Nagoya, JP;
Assignee:
NGK Spark Plug Co., Ltd., , JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01T / ; H01T / ; F02P / ;
U.S. Cl.
CPC ...
313141 ; 313137 ; 313143 ; 445-7 ; 1231 / ; 1231 / ;
Abstract
A heater-equipped spark plug comprises an insulator having an insulator nose which holds thereon a center electrode in the vicinity of a free end of an axial bore, a lead wire arranged along a surface of the insulator, a heater formed on the insulator nose by baking a metal paste and connected to the lead wire; and a high softening-point glass layer covering and holding the heater in place with an alumina layer interposed between the high softening-point glass and the heater. Preferably, the alumina layer can have a thickness of 20-200 .mu.m and the high softening-point glass layer can have a thickness of 30-500 .mu.m.