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. 13, 2007
Filed:
Oct. 15, 2004
Applicant:
Keiji Kanao, Chita-gun, JP;
Inventor:
Keiji Kanao, Chita-gun, JP;
Assignee:
Denso Corporation, Kariya, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01T 13/20 (2006.01);
U.S. Cl.
CPC ...
Abstract
A spark plug is disclosed as including a metal shellformed with first and second boresand a stepped sectionbetween the first and second bores, and a porcelain insulatorhaving a largest-diameter section, which is accommodated in the first bore and a small-diameter sectionaccommodated in the second bore. The first and second bores of the metal shell have a dimensional relationship, lying in a value equal to or less than 1.8 mm, which is expressed as (D−D)/2 where Drepresents an inner diameter of the first bore of the metal shell and Drepresents an inner diameter of the second bore of the metal shell.