| 摘要 |
PROBLEM TO BE SOLVED: To prevent a thin steel plate from being excessively melted when welding a projection bolt to the thin steel plate.SOLUTION: A projection bolt 1 is formed by a shaft part 2, an enlarged diameter part 3 integral with the shaft part and a welding projection 4. A welding current for melting only the welding projection 4 is applied to the welding projection, a plastic deformation part 7 including a melting part 7A and a softening part 7B is formed between the welding projection 4 and the enlarged diameter part 3, the volume of the plastic deformation part 7 is set smaller than the volume of the welding projection 4, and an inclination angleθ1 of an enlarged diameter part inclined plane 6 is set smaller than a taper inclination angleθ2 of the welding projection 4. Much melting heat is passed through the volume-reduced plastic deformation part 4 and positively transmitted to the bolt to prevent excessive melting of a steel plate component 9. |
