Method of making a spark plug

摘要

Provided is a method of making a spark plug (100) having a noble metal chip (32) joined to an electrode main body (4m) of a ground electrode (4) by interposing therebetween an intermediate member (33). The method comprises the steps of prior to joining the noble metal chip (32) to the electrode main body (4m), joining the intermediate member (4m) and the noble metal chip (32) together, placing a noble metal chip and intermediate member assembly (34) on the electrode main body (4m) in a way as to allow the intermediate member (33) to contact the electrode main body (4m), and welding the electrode main body (4m) and the intermediate member (33) together while restricting relative movement of the electrode main body, (4m) and the intermediate member (33) without applying an urging force to a joint between the intermediate member (33) and the noble metal chip (32).