| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of high-quality die casting which discharges an impure gas inside a cavity outside through a sleeve by forcing nonflammable gas into the cavity so that the impure gas is replaced with the nonflammable gas. <P>SOLUTION: A forming die B is equipped with a valve type degassing device 1A which communicates with the cavity C. In a die casting machine, a sleeve 81 leading to the forming die is equipped with a molten metal supply port 82 and a molten metal extruding plunger 83. A suction passage 3 equipped with a vacuum tank 31 and a gas force-feeding passage 2 equipped with a gas source 21 lead to the valve type degassing device switchably. Until the completion of filling the cavity with the molten metal from just before the completion of mold clamping, the nonflammable gas is forced into the cavity from the gas source through the degassing device so that at least the impure gas confined in the forming die is discharged outside from the molten metal supply port and the impure gas in the cavity is replaced with the nonflammable gas. The nonflammable gas in the cavity is sucked into the vacuum tank through the degassing device in the middle of molten metal filling. <P>COPYRIGHT: (C)2012,JPO&INPIT |
