| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing the spark plug of an internal combustion engine capable of suppressing the flying spark.SOLUTION: A method of manufacturing a spark plug 1 in which at least one of a center electrode 2 and a ground electrode 3 includes a discharge chip 5. In a chip manufacturing step, a discharge part 51 arranged on a spark discharge gap 11 side, and a base metal joint part 52 composed of a material having a melting point lower than that of the discharge part 51 and being joined to an electrode base metal 30 are joined each other to manufacture the discharge chip 5. In a temporary joining step, the discharge chip 5 is joined temporarily to the electrode base metal 30 at the base metal joint part 52, by resistance welding. In the main joining step, a portion of the base metal joint part 52 and a portion of the electrode base metal 30 are melted by laser welding, and solidified, thus joining the discharge chip 5 to the electrode base metal 30 so that the side face 511 of the discharge part 51 and the surface of the electrode base metal 30 are connected smoothly. |
