| 摘要 |
PROBLEM TO BE SOLVED: To provide a hollow shaft manufacturing method capable of preventing generation of thickness drop defect in an inner face of a hollow part of a work. SOLUTION: Firstly, a punch 61 is press-fitted to a work 1 loaded on a first die 80, and a prepared hole 11 for forming a hollow part in which a tip thereof reaches a vicinity of a flange forming scheduled position 21a is formed. Next, a work 10 is loaded on a second die 70 having a flange forming part 72, and a flange 21 is formed by pressing a circumferential wall end face 11a of the prepared hole 11 while the inner and outer diameters of the circumferential wall 11c of the prepared hole 11 are maintained constant. Finally, a work 20 having the flange formed thereon is loaded on a third die 80, a punch 85 is press-fitted into a prepared hole 22, and the prepared hole 22 is expanded along the axis. COPYRIGHT: (C)2006,JPO&NCIPI
|
