| 摘要 |
A spark plug in which the rising of a ground electrode is more reliably restrained. The spark plug includes a ground electrode having a core portion extending from a proximal end section toward a distal end section via a bent section, a heat transfer portion extending from the proximal end section toward the distal end section via the bent section, and an external layer located externally of the core portion and the heat transfer portion and extending from the proximal end section to the distal end section via the bent section. As viewed on a section of the ground electrode taken orthogonally to a direction along which the ground electrode extends, at least at an intermediate position of the bent section with respect to the direction, the center of the core portion is offset toward a center electrode from the center of the heat transfer portion. |
