发明名称 |
SPARK PLUG, AND ITS MANUFACTURING METHOD |
摘要 |
<p>A spark plug of the present invention includes a cylindrical metal shell, a cylindrical ceramic insulator retained in the metal shell, a center electrode retained in the ceramic insulator and extending in an axial direction, and a ground electrode formed into a bent shape and having a rear end portion fixed to the metal shell and a front end portion facing a front end portion of the center electrode with a gap left therebetween. The ground electrode contains a large thickness region formed on a rear end side thereof with a large thickness, a small thickness region formed on a front end side thereof with a smaller thickness than that of the large thickness region, a protruding region formed on the small thickness region and facing the center electrode and a thickness changing region formed between the large thickness region and the small thickness region and located at a different position from a position of a minimum curvature radius region of the bent shape of the ground electrode.</p> |
申请公布号 |
EP2131461(A1) |
申请公布日期 |
2009.12.09 |
申请号 |
EP20080738981 |
申请日期 |
2008.03.27 |
申请人 |
NGK SPARK PLUG CO., LTD. |
发明人 |
NAKAYAMA, KATSUTOSHI;NAGASAWA, SATOSHI |
分类号 |
H01T13/32;H01T13/20;H01T21/02 |
主分类号 |
H01T13/32 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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