| 摘要 |
In the present invention, a spark plug is orthogonal to the longitudinal direction of an electrode parent material. The surface of the parent material is exposed in a cross-section of a ground electrode through which the axis of an electrode tip passes. The following relationships are fulfilled: 1.2 E≤F≤1.9 E, 0.05 mm≤Da≤0.30 mm, 0.05 mm≤Db≤0.30 mm, and 0.20 mm2≤J≤0.70 mm2. |
