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:
Sep. 04, 1990
Filed:
Dec. 07, 1988
Applicant:
Inventors:
Assignee:
NGK Spark Plug Co., Ltd., Nagoya, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01T / ; H01T / ;
U.S. Cl.
CPC ...
313120 ; 313 115 ; 313139 ;
Abstract
This invention provides an igniter plug, having a plurality of grooves within an outer surface of an annular ground electrode (2), the diameter of which is reduced to about 13 mm. Each groove (6) generally has a semi-circular shape in cross section to allow air flow along the grooves (6), with the number of the grooves (6) in the range from 4 to 16, and the width of each groove is to about 1.0 mm to 2.5 mm. The semi-circular cross section of the grooves (6) makes it possible to provide a large surface for the grooves without increasing the amount of machining, thus, enhancing cooling efficiency when the air flows along the grooves.