| 摘要 |
PROBLEM TO BE SOLVED: To provide a spark plug for an internal combustion engine of high degree of freedom in design, which is able to prevent deformation of a terminal fitting.SOLUTION: A spark plug 1 for an internal combustion engine has a housing 2, an insulator 3, a center electrode 4, a terminal fitting 6, a grounding electrode 5, a resistor 7, and sealing materials 121, 122. The terminal fitting 6 has: a fitting part 61 to be fitted in the inner periphery of the basal end of the insulator 3; and a small diameter part 62 extended from the fitting part 61 toward the leading-end side and having a diameter smaller than the fitting part 61. The small-diameter part 62 is formed by providing ribs 63 at a plurality of points in a circumferential direction, each rib projecting out from the outer periphery and extending along the axial direction. The sealing material 121 is also provided in part of at least the leading end of a space 13 between the outer periphery of the terminal fitting 6 and the inner periphery of the insulator 3.SELECTED DRAWING: Figure 1 |
