| 摘要 |
PURPOSE:To recover gas and reuse and protect the surrounding area from bad effect of gas pressure by providing a gas injection and discharge mechanism in a mold and connecting a gas path formed with a feeding path and a circulating path with said mechanism. CONSTITUTION:A nozzle for filling molten resin into a cavity is installed in a fixed mold 1, and a gas injection and discharge mechanism 3 is provided in a movable mold 2. A check valve 24, a compressor 25, a surge tank 26 and a cylinder valve 28 are installed in the downstream of a gas bomb 5 in a feeding path 21 of a gas path 4. One end of a gas circulating path 22 is connected with an area between the gas exhaust mechanism 3 and the cylinder valve 28 and the other end is connected with an area between the check valve 24 and the compressor 25, and cylinder valves 31 and 32 and check valves 33 and 34 are installed on respective terminal sides, while a surge tank 35 is mounted on a middle section. High pressure gas flows into the resin before being solidified in a cavity 7 through the gas injection and discharge mechanism to form a hollow section, and the gas is discharged after being solidified. At that time, the cylinder valve 28 in the feeding path 21 is closed and the cylinder valve 31 in the circulating path 22 is opened, and the gas is returned to the feeding path 21 through the surge tank 35. |
