PURPOSE: To prevent the bending caused by welding of a shaft member as excellent workability is kept by welding a cam member and the shaft member through high energy beam as a cam shaft material is rotated at high speed.
CONSTITUTION: After a cam member 1 is fitted to a shaft member 2, the cam member 1 is set at a fixed position on the shaft member 2, and the cam member 1 and the shaft member 2 are welded through a high energy beam 4 as a cam shaft material 3 is rotated at high speed around its central axis. Thus, in order to heat the shaft member 2 slowly and uniformly over its whole circumference, a part to be welded is welded after its whole circumference is preheated about simultaneously and at similar rate. In addition to that, since the welded part is solidified at about similar rate over its whole circumference during a cooling process after welding, a local tensile stress is difficult to occur during its solidifying process, and the occurrence of bending of the shaft member 2 can therefore be controlled.
SHIBATA SHINYA
HANAKAWA KATSUNORI
NOMURA SEIJI
