公开(公告)号：US09065255B2

公开(公告)日：2015-06-23

申请号：US13847770

申请日：2013-03-20

Applicant: NGK SPARK PLUG CO., LTD.

Inventor： Nobuaki Sakayanagi ,  Shinya Mitsuda ,  Tomoaki Kato ,  Ryuichi Ono

IPC: H01T13/20 ,  H01T21/02 ,  H01T13/32

CPC classification number: H01T13/32 ,  H01T21/02

Abstract: A spark plug includes: a rod-shaped center electrode extending in an axial direction; an insulator including a shaft hole that holds the center electrode inside of the shaft hole; a metal shell surrounding and holding a part of the insulator; and a ground electrode including a base end welded to the metal shell. The metal shell and the ground electrode are joined via a fusion portion formed by welding the ground electrode and the metal shell together. When the smallest thickness of the fusion portion in the axial direction is A, when, in a cross section that includes a center line of the ground electrode and is parallel to the axis, a length of a ground-electrode-side melted boundary formed between the fusion portion and the ground electrode is B, and when the ground electrode thickness is C, conditions of A≧0.2 mm and B>C are satisfied.

Abstract translation: 火花塞包括：沿轴向延伸的杆状中心电极; 绝缘体，其包括将所述中心电极保持在所述轴孔内部的轴孔; 围绕并保持绝缘体的一部分的金属壳; 以及包括焊接到金属壳的基端的接地电极。 金属壳和接地电极通过将接地电极和金属壳焊接在一起而形成的熔接部分接合。 当熔融部分的轴向最小厚度为A时，当在包括接地电极的中心线并且平行于轴线的横截面中，形成在接地电极侧熔融边界之间的长度 熔接部和接地电极为B，当接地电极厚度为C时，满足A≥0.2mm，B> C的条件。

公开(公告)号：US09742157B2

公开(公告)日：2017-08-22

申请号：US15025609

申请日：2014-08-20

Applicant: NGK SPARK PLUG CO., LTD.

Inventor： Shinya Mitsuda ,  Yuichi Yamada

IPC: H01T13/20 ,  H01T13/38

CPC classification number: H01T13/20 ,  H01T13/38

Abstract: A spark plug includes an insulator having a through hole formed in the direction of an axis, a rod-shaped center electrode inserted in the through hole and extending in the direction of the axis, a metal shell disposed around an outer circumference of the insulator, and a ground electrode electrically conducted with the metal shell and adapted to define a gap between the ground electrode and the center electrode. A front end part of the insulator has a front end surface, an outer circumferential surface and a curved surface region formed between the front end surface and the outer circumferential surface. In a cross section including the axis, a front end of an inner circumferential surface of the metal shell faces the curved surface region in a direction perpendicular to the axis. The curved surface region has a curvature radius of 0.2 mm to 0.8 mm.

公开(公告)号：US20130278133A1

公开(公告)日：2013-10-24

申请号：US13847770

申请日：2013-03-20

Applicant: NGK SPARK PLUG CO., LTD.

Inventor： Nobuaki Sakayanagi ,  Shinya Mitsuda ,  Tomoaki Kato ,  Ryuichi Ono

IPC: H01T13/32

CPC classification number: H01T13/32 ,  H01T21/02

Abstract: A spark plug includes: a rod-shaped center electrode extending in an axial direction; an insulator including a shaft hole that holds the center electrode inside of the shaft hole; a metal shell surrounding and holding a part of the insulator; and a ground electrode including a base end welded to the metal shell. The metal shell and the ground electrode are joined via a fusion portion formed by welding the ground electrode and the metal shell together. When the smallest thickness of the fusion portion in the axial direction is A, when, in a cross section that includes a center line of the ground electrode and is parallel to the axis, a length of a ground-electrode-side melted boundary formed between the fusion portion and the ground electrode is B, and when the ground electrode thickness is C, conditions of A≧0.2 mm and B >C are satisfied.

Abstract translation: 火花塞包括：沿轴向延伸的杆状中心电极; 绝缘体，其包括将所述中心电极保持在所述轴孔内部的轴孔; 围绕并保持绝缘体的一部分的金属壳; 以及包括焊接到金属壳的基端的接地电极。 金属壳和接地电极通过将接地电极和金属壳焊接在一起而形成的熔接部分接合。 当熔融部分的轴向最小厚度为A时，当在包括接地电极的中心线并且平行于轴线的横截面中，形成在接地电极侧熔融边界之间的长度 熔接部和接地电极为B，当接地电极厚度为C时，满足A> = 0.2mm，B> C的条件。