发明名称 |
Spark plug and method for manufacturing the spark plug |
摘要 |
A ground-electrode spark portion 32 is formed from a noble metal which contains Pt as a main component, and is joined to a main metal portion of the ground electrode 4 via an alloy layer which has a thickness ranging from 0.5 mu m to 100 mu m and in which the noble metal that constitutes the ground-electrode spark portion 32 and the metal that constitutes the main metal portion of the ground electrode 4 are alloyed with each other. The ground-electrode spark portion 32 is configured such that a distal end surface 32t facing a spark discharge gap g is smaller in diameter than a bottom surface 32u joined to the ground electrode 4; and the distal end surface 32t is protrusively located beyond the side surface 4s of the ground electrode 4. When the ground-electrode spark portion 32 is viewed in plane from the distal end surface 32t, a portion of the surface of the ground-electrode spark portion 32 is viewed as a peripheral exposed-region surface 32p which is exposed on the side surface 4s of the ground electrode 4 in such a manner as to surround the distal end surface 32t. <IMAGE> |
申请公布号 |
EP1376791(A1) |
申请公布日期 |
2004.01.02 |
申请号 |
EP20030253876 |
申请日期 |
2003.06.19 |
申请人 |
NGK SPARK PLUG COMPANY LIMITED |
发明人 |
TERAMURA, HIDEKI;KATO, TOMOAKI;TORII, KAZUYOSHI |
分类号 |
H01T13/00;H01T13/32;H01T21/02 |
主分类号 |
H01T13/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|