JP2017083129A5

JP2017083129A5 -

Info

Publication number: JP2017083129A5
Application number: JP2015214663A
Authority: JP
Filing date: 2015-10-30
Publication date: 2018-09-20
Anticipated expiration: 2035-10-30

Description

（１）本発明の一形態によれば、軸線方向に延びる側面部と、前記側面部の先端側に接続され、前記側面部の先端側を閉じてなる先端部と、を有するシース管と、前記シース管内に前記軸線方向に延びるように配置され、自身の先端部が前記シース管の先端部と接続された発熱コイルと、を備えるグロープラグが提供される。このグロープラグでは、前記発熱コイルの先端部は、前記シース管の先端部に取り囲まれつつ埋め込まれてなり；前記シース管の先端部と前記発熱コイルとの間の前記シース管を構成する金属と前記発熱コイルを構成する金属との合金からなる合金部の厚さは１０（μｍ）以下であり；前記軸線方向において、前記発熱コイルが配置された部位に対応する前記シース管の側面部の厚さのうち、最小の厚さＡと；前記シース管の先端から前記発熱コイルの先端までの前記軸線方向における距離Ｂと；前記シース管の先端部の前記軸線方向ＯＤにおける最大の厚さＣと、は、
Ｂ＞Ａ・・・式（１）
Ｃ／Ａ≦２．５・・・式（２）
の関係を満たすことを特徴とする。このような形態のグロープラグであれば、グロープラグの耐久性と急速昇温性とを確保することができる。 (1) According to one aspect of the present invention , a sheath tube having a side surface portion extending in the axial direction and a distal end portion connected to the distal end side of the side surface portion and closing the distal end side of the side surface portion; There is provided a glow plug provided with a heat generating coil disposed in the sheath tube so as to extend in the axial direction and having a distal end portion thereof connected to the distal end portion of the sheath tube. In this glow plug, the distal end portion of the heat generating coil is embedded while being surrounded by the distal end portion of the sheath tube; and the metal constituting the sheath tube between the distal end portion of the sheath tube and the heat generating coil; The thickness of the alloy portion made of an alloy with the metal constituting the heating coil is 10 (μm) or less; in the axial direction, the thickness of the side surface portion of the sheath tube corresponding to the portion where the heating coil is disposed Among them, the minimum thickness A; the distance B in the axial direction from the distal end of the sheath tube to the distal end of the heating coil; and the maximum thickness C in the axial direction OD of the distal end portion of the sheath tube , Is
B> A Formula (1)
C / A ≦ 2.5 (2)
It is characterized by satisfying the relationship. With such a form of glow plug, it is possible to ensure the durability and rapid temperature rise of the glow plug.

Claims

A sheath tube having a side surface portion extending in the axial direction, and a front end portion connected to the front end side of the side surface portion and closing the front end side of the side surface portion;
A glow plug including a heating coil disposed in the sheath tube so as to extend in the axial direction and having a distal end portion connected to the distal end portion of the sheath tube;
The tip of the heating coil is embedded while being surrounded by the tip of the sheath tube,
The thickness of the alloy portion made of an alloy of the metal constituting the sheath tube and the metal constituting the heat generating coil between the distal end portion of the sheath tube and the heat generating coil is 10 (μm) or less,
In the axial direction, the minimum thickness A among the thicknesses of the side surfaces of the sheath tube corresponding to the portion where the heating coil is disposed,
A distance B in the axial direction from the distal end of the sheath tube to the distal end of the heating coil; and
The maximum thickness C of the distal end portion of the sheath tube in the axial direction is:
B> A
C / A ≦ 2.5
Satisfying the relationship of
Glow plug.

The glow plug according to claim 1,
The glow plug according to claim 1, wherein a tip portion of the heating coil is linear.

The glow plug according to claim 1,
The glow plug according to claim 1, wherein a tip portion of the heating coil is spiral.