| 摘要 |
A spark plug in which a distal end portion (60) of a crimp portion (53) of a metallic shell (50) is crimped by bending the distal end portion inward, whereby the metallic shell (50) and an insulator (10) are fixed together with a first packing (6), a second packing (7), and talc (9) being present therebetween. The first packing (6) assumes an annular shape and has a circular cross section. A minimum diameter portion of the crimp portion (53), which portion is closest to the outer circumferential surface (17) of a trunk portion (18), is located at the position of the center line of the first packing (6) or inward thereof with respect to the axis O. The crimp portion (53) does not come into contact with the insulator (10), and the first packing (6) comes into contact with the insulator (10). Furthermore, the first packing (6) has a hardness that is lower than that of the crimp portion (53).
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