グロープラグ - Nippon Special Ceramics Co., Ltd.

Title:

グロープラグ

Document Type and Number:

Japanese Patent JP7045161

Kind Code:

B2

Abstract:

To provide a glow plug capable of preventing local exhaustion of a tube to improve durability of a heating coil.SOLUTION: A glow plug comprises a metal tube, a heating coil mainly consisting of W arranged in the tube, and insulating powder encapsulated in the tube. The tube comprises a cylindrical base material part, and a molten part formed at a tip side of the base material part and in which a tip of the heating coil is buried and then molten with welding. An external surface of the tube is made gradually recessed toward a boundary between the base material part and the molten part so that the boundary is recessed at the maximum. On a cross section including an axial line, an angle formed by a tangential line of an external surface of the base material part passing through an intersection between the external surface of the tube and the boundary, and a tangential line of an external surface of the molten part passing through the intersection of the external surface of the tube and the boundary is equal to or larger than 146°.SELECTED DRAWING: Figure 3

Inventors:

Makoto Ejiri
Hirofumi Okada

Application Number:

JP2017197337A

Publication Date:

March 31, 2022

Filing Date:

October 11, 2017

Export Citation:

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