To increase thickness of at least a part of a bent part of a press-made workpiece while suppressing wrinkles.
A press-made workpiece W is prepared, which comprises an end wall 1, a bent part 2 which is bent to one side from an outer periphery of the end wall 1, and a cylindrical part 3 continuous to the bent part 2. When increasing thickness of at least a part of the bent part 2 of the workpiece W, the workpiece W is clamped by a clamp punch 10 to be adapted to an inner surface of the workpiece W, a clamp die 24 to be adapted to an outer surface of the end wall 1, and a thickness increase guide die 29 which is fitted to its outer periphery in an axially slidable manner, and adapted to the outer peripheral surfaces of the bent part 2 and the cylindrical part 3. A thickness-increasing punch 13 is inserted in a space 15 formed between the clamp punch 10 and the thickness increase guide die 29. The bent part 2 is thickness-increased by applying the compression load in the axial direction to the cylindrical part 3, and the thickness increase guide die 29 is retracted from the clamp die 24 according to the thickness increase.
AOKI TOSHIHIDE
NAKATA AKIFUMI
| JP2000176557A | 2000-06-27 | |||
| JPS6286927U | 1987-06-03 | |||
| JP3594845B2 | 2004-12-02 | |||
| JPS53134762A | 1978-11-24 | |||
| JP2000176557A | 2000-06-27 | |||
| JPS6286927U | 1987-06-03 | |||
| JP3594845B2 | 2004-12-02 |
Kazuaki Niki
Nude Shima Shinji