| 摘要 |
PROBLEM TO BE SOLVED: To avert the degradation defects of optical output caused by the weld slag, foreign matter, etc., which shut off an optical signal transmission route are causative by suppressing the generation of sparks at the time of resistance welding of a metallic holder and a stem to substantially prevent the generation of the welding slag and to facilitate the removal of the unavoidably advanced foreign matter, such as dust. SOLUTION: At least a projection ring 3d part of the metallic holder 3 having a projection consisting of a stainless steel blank is subjected to Ni plating, etc., by which the formation of an insulative oxidized film on the welded surface is obviated, the contact resistance is suppressed to a lower level and the generation of the sparks is lessened. In addition, the staircase-like cap relief part 3b of the metallic holder 3 is tapered to allow the removal of the unavoidably infiltrating foreign matter, etc., by the simple air blow alone. |
