| 摘要 |
PURPOSE:To perform pressurizing of a molten metal and as-cast hole and to prevent the generation of a casting defect and casting by projecting the 1st pressurizing member into a cavity when the molten metal is in the initial stage of a semi-molten state. CONSTITUTION:A stationary die 6 and a movable die 8 are mated in the 1st stage to form a cavity 10 and an injection cylinder is operated to charge a molten metal into the cavity 10. The 1st driving cylinder 13 is advanced in the 2nd stage to project the 1st pressurizing member 15 into the cavity 10. The molten metal in this stage is in the initial stage of the semi-molten state in which the rate of a solid phase is >=20% and <50%. The molten metal is pressed and is cast with a hole. The 2nd driving cylinder 17 is advanced in the 3rd stage to move forcibly the 2nd pressurizing member 22 toward the cavity 10. The molten metal in this stage is in the late period of the semi-molten state in which the ratio of the solid phase is >=50% and <90%. The molten metal is thus pressurized. The 1st and 2nd pressurizing members 15, 22 are retreated upon solidification of the molten metal and the release of a casting is accomplished. |
