| 摘要 |
PURPOSE:The captioned device of a small size and reduced mechanical operations which presses the molten metal having been high-frequency-heated and held in a crucible by surface tension after detecting its temperature and pours the same into the vacuumed porous mold through the small hole of the crucible. CONSTITUTION:Metal material 38 for miniature precision casting for dental technique or the like is put in a crucible 26 which is then placed on the table 15 in a melting chamber 12. On the other hand, a mold 32 is placed on the table 29 in a casting chamber 13 and the table 29 is moved upward to be closely contacted with the bottom surface of the table 15 so that a pouring port 33 is put in alignment to a small hole 27 and cross gate 15a. The chambers 12, 13 are hermetically closed and the vacuum chamber 14 is held vacuumed. Next, high-frequency electric current is flowed to a heating coil 21 to melt the material, but the molten metal does not flow out through the small hole owing to surface tension. The molten metal is kept at a fixed temperature by the detection of a sensor 19 and when the temperature reaches the specified one, valves 24, 31 open to inject Ar gas into the chamber 12 and pressurize the same, at the same instant of which the air in the chamber 13 is instantaneously exhausted into the chamber 14. This causes the molten metal to be sucked to the room 13 side through the entire surface of the porous mold, whereby pouring is done. |
