To provide a hydraulic forming method causing no forming failure by residual gas by surely eliminating gas such as air in a space in a material to surely prevent gas such as air from remaining in a space in a protrusion in a forming material when carrying out hydraulic forming such as hydroforming using the forming material having the upward projecting protrusion.
An aperture communicating with the outside of the forming material is formed in the protrusion in a stage prior to filling a pressurizing liquid in the forming material. Prior to mold clamping, the pressurizing liquid is filled in the material, and gas existing in the inside space of the protrusion is ejected to the outside of the forming material through the aperture. Mold clamping is then performed, and the inside space of the forming material is pressurized by the pressurizing liquid to carry out forming.
MIZUMURA MASAAKI
| JPS4422379Y1 | 1969-09-20 | |||
| JP2005297060A | 2005-10-27 |
Tadashi Takahashi
Sumio Tanai
Hiroshi Masui
Tomoo Katsumata