Title:
SPARK PLUG
Document Type and Number:
Japanese Patent JP2005228562
Kind Code:
A
Abstract:
To ensure weld strength of a ground electrode to a mounting metal fitting, having a M18-size screw or larger screw.
The mounting metal fitting 10 has a mounting screw 11 of M18 or more around it, and has an opened ring structure on one end. Given a half (1/2) of the difference between inside diameter and outside diameter of one end 12 of the mounting metal fitting 10 as B, a half of the difference between the inside and the outside diameters of the metal fitting 10 shifted by 0.5 mm from the end 12 to the screw 11 as C, and a half (1/2) of the difference between the inside diameter of mounting fitting 10 and the outside diameter of the screw 11 as D, it has a feature of satisfying the relation: 0.7≤B/C≤1.0 and 0.20<B/D<0.65.
Inventors:
WATANABE TETSUYA
Application Number:
JP2004035208A
Publication Date:
August 25, 2005
Filing Date:
February 12, 2004
Export Citation:
Assignee:
DENSO CORP
International Classes:
F02P13/00; H01T13/20; H01T13/32; H01T13/39; (IPC1-7): H01T13/20; F02P13/00
Attorney, Agent or Firm:
Yoji Ito
Takahiro Miura
Fumihiro Mizuno
Takahiro Miura
Fumihiro Mizuno