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. 15, 1981
Filed:
Mar. 14, 1979
Applicant:
Inventors:
Assignees:
Toyota Jidosha Kogyo Kabushiki Kaisha, Toyota, JP;
NGK Spark Plugs Co., Ltd., Nagoya, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01T / ; H01T / ;
U.S. Cl.
CPC ...
313143 ;
Abstract
A spark plug is disclosed, in which the insulator is formed with a stepped portion near its tip portion and the housing which surrounds the insulator is formed with an inner constriction which opposes the smaller portion of the insulator, near the stepped portion, with a small annular gap being left therebetween, thereby hindering the entry of air/fuel mixture and carbon particles into the inner space between the housing and the insulator, and thus reducing the buildup of carbon on the insulator.