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. 23, 1999
Filed:
Jun. 06, 1997
Yoshihiro Matsubara, Nagoya, JP;
Tetsushi Suzuki, Nagoya, JP;
Yuuji Hirano, Nagoya, JP;
Kazuya Iwata, Nagoya, JP;
NGK Spark Plug Co., Ltd., Nagoya, JP;
Abstract
A spark plug has a cylindrical metal shell, a ground electrode and an insulator fixedly supported within the metal shell with a front end of the insulator extended beyond a front end of the metal shell. The insulator has an axial bore in which a center electrode is placed to form a spark gap with the ground electrode. The front end of the metal shell is generally flush with or somewhat recessed into an inner wall of a combustion chamber of an internal combustion engine when the spark plug is mounted on a cylinder head of the engine. The front end of the insulator extends at least 4.0 mm from the front end of the metal shell.