| 摘要 |
PROBLEM TO BE SOLVED: To more firmly fix a blade by swaging.SOLUTION: A punch for rough swaging having a punch face forming an acute angle with respect to the punch pressing direction on an outer side in the radial direction of a shell 2 is pressed against an inner circumferential side part 27 of the shell 2, and then, a punch for finish swaging forming an angle of its punch face with respect to the punch pressing direction being larger than that of the punch for rough swaging is pressed against a part swaged by the rough swaging step to fix a blade 4 to the shell 2. |
