| 摘要 |
PROBLEM TO BE SOLVED: To obtain an appropriate gap of a spark plug having a sub-combustion space.SOLUTION: A spark plug has a center electrode extending in the axial direction, an insulator having a shaft hole extending in the axial direction, and provided with a center electrode on the tip side of the shaft hole, a main metal fitting arranged on the outer periphery of the insulator, and a cap member having a ground electrode arranged via a gap for the side face of the center electrode, fixed to the tip of the main metal fitting and forming a sub-combustion chamber in conjunction with the main metal fitting. When manufacturing such a spark plug, relative position of the cap member and the center electrode is fixed, while arranging a gap formation member for forming a gap between the side face of the center electrode and the ground electrode. The cap member may have a first member and a second member. The first member is a member having the ground electrode, and a fixing portion being fixed to the tip of the main metal fitting. The second member is a member being fixed to the first member. |
