JPS60140390U

JPS60140390U - spark plug

Info

Publication number: JPS60140390U
Application number: JP2766084U
Authority: JP
Inventors: 光岡　照久
Original assignee: 日本特殊陶業株式会社
Priority date: 1984-02-27
Filing date: 1984-02-27
Publication date: 1985-09-17

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of the drawing]

第１図および第２図は、本考案の点火プラグの第１の実
施例を示した側面図と上面図、第３図および第４図は第
２の実施態様についての同じく側面図と上面図、そして
第５図は、本考案の点火プラグと、−これと同種の在来
の点火プラグの希薄着火限界の比較評価グラフである。図中、１・・・棒状中心電極、２・・・絶縁体、３・・
・筒状取付金具、４・・・棒状外側電極、Ｃ・・・中心
電極の凹孔、ｄ・・・中心電極の環状凸出部、ｅ・・・
外側電極のくり抜き孔、ｆ・・・外側電極の環状凸出部
、Ａ・・・放電間隙、Ｂ・・・在来点火プラグの希薄着
火限界グラフ、Ｃ・・・本考案点火プラグの希薄着火限
界グラフ。1 and 2 are a side view and a top view showing a first embodiment of the spark plug of the present invention, and FIGS. 3 and 4 are a side view and a top view of a second embodiment. , and FIG. 5 is a comparative evaluation graph of the lean ignition limit of the spark plug of the present invention and a conventional spark plug of the same type. In the figure, 1... Rod-shaped center electrode, 2... Insulator, 3...
- Cylindrical mounting bracket, 4... Rod-shaped outer electrode, C... Recessed hole of center electrode, d... Annular protrusion of center electrode, e...
Hollowed hole in outer electrode, f... Annular protrusion of outer electrode, A... Discharge gap, B... Lean ignition limit graph of conventional spark plug, C... Lean ignition of spark plug of the present invention. limit graph.

Claims

[Scope of utility model registration request]

(1) A cylindrical mounting bracket is fitted around the rod-shaped center electrode via an insulator, and the rod-shaped outer electrode attached to the tip of the metal fitting is made such that its tip rests on the axis of the center electrode. In the spark plug having a structure in which the center electrode is bent to face a center electrode, the peripheral edge of the tip surface of the center electrode is protruded in an annular shape, and a through hole is provided coaxially so as to face the annular protrusion. An ignition plug characterized in that a discharge portion having a peripheral edge of the through hole protruding in an annular shape is formed at the tip of the outer electrode.

(2) A utility model characterized in that the annular discharge end of the center electrode and/or the outer electrode is made of platinum, platinum alloy, or other noble metal that has excellent chemical inertness and high heat resistance. A spark plug according to registered claim 1.