PURPOSE: To certainly prevent the welding distortion of a shaft and to slowly cool its welded zone by inserting a mandrel into a hollow part while the welded zone of a shaft member is in a state of high temperature to correct the distortion of the welded zone.
CONSTITUTION: After a mandrel 3 is inserted into a hollow part 21 of a shaft member 2, it is stopped when its top attains a right portion to be welded on a cam lobe 1, and the right end 12 of the cam lobe 1 and the shaft member 2 are welded through a high energy beam. The mandrel is advanced to the left while the welded part 22 of the shaft member 2 is still in a state of high temperature, and stopped when its top attains on this side of a portion to be welded next. Thus, the welded part 22 of the shaft member 2 has been distorted once by the heat of the high energy beam, but the mandrel 3 is inserted during the high temperature state of the welded part 22, the distortion of the welded part 22 can be easily corrected. In addition to that, the mandrel 3 can absorb the heat of the welded part 22 to slowly cool the welded part.
YOSHIMOTO KAZUYUKI
KAWATO YASUSHI
OGASAWARA TORU
