GAS RECOVERY METHOD IN GAS ASSIST INJECTION MOLDING AND GAS ASSIST INJECTION MOLDING MACHINE THEREFOR

摘要

PURPOSE: To obtain a gas recovery method in gas assist injection molding and a gas assist injection molding machine therefor by which a high-pressure gas can be recovered without using a large-size gas recovery tank. ;CONSTITUTION: Using a high-pressure gas supply device provided with a first pressure increasing mechanism 20 increasing the pressure of a gas introduced to gas chambers 22C, 22D to a predetermined pressure and a second pressure increasing mechanism 30 having a compression cylinder 32 to which the high- pressure gas fed from the gas chambers 22C, 22D is itroduced and a drive cylinder 31 driving the compression cylinder 32 for boosting the high-pressure gas from the first pressure increasing mechanism 20, the high-pressure gas is injected into a melt resin 4 charged in a mold 2 to mold the melt resin 4. After that, when the gas is discharged from the inside of the melt resin 4, the gas is recovered into the drive cylinder 31 of the second pressure increasing mechanism 30 to be reused.;COPYRIGHT: (C)1995,JPO