A method of making a spark plug.

摘要

The present invention provides a method of making a spark plug, by which a noble metal tip is secured to a front end of a centre electrode, the noble metal being resistant to spark erosion. There is provided a method of making a spark plug which includes an electrode blank metal (1) to which an erosion resistant disc-shaped tip (2) is secured, the method comprising steps of: (i) providing an electrode blank metal (1) with a neck portion (1a); (ii) arranging said disc-shaped tip (2) on an end surface (13) of said neck portion (1a); and (iii) securing said tip (2) to said end surface (13) of said neck portion (1a) by pressing said tip to close against said end surface (13) and simultaneously applying a laser beam around the circumference of the interface between said disc-shaped tip (2) and said end surface (13) of said neck portion (1a) thereby forming weld (3) at the interface therebetween. A recess may be provided on the end surface in which said tip may be secured. <IMAGE>