| 摘要 |
PURPOSE:To easily obtain a die cast product of good quality free from any cavity by filling a reactive gas in the cavity of clamped dies, and evacuating the reactive gas during injection of molten metal. CONSTITUTION:After dies are clamped, a reactive gas is supplied into a cavity from a reactive gas supply source 14 to exhaust air and fill the cavity with the reactive gas. Thence, molten metal is injected. At the same time, a solenoid valve 15 opens and the reactive gas is exhausted by a vacuum pump 18 through a valve 15 and a bypass 4. The remained reactive gas reacts with the molten metal. When the molten metal fills in the cavity 2, the valve head 5b of the valve 5 is pushed up to close the bypass 4. Upon ending of the injection, the solenoid valve 15 closes. After cooling a cylinder 8 is operated to release the coupling between the molten metal solidified in the passage 3 and the bypass 4, and the valve head 5b of the valve 5. Thence, the dies are opened, and the solidified metal is remoed from a stationary die 7. |
