| 摘要 |
PROBLEM TO BE SOLVED: To provide a gas injecting nozzle of a gas injection molding device, which is capable of effecting high-pressure gas injection and discharge in gas injection molding method surely within a short period of time and having durability. SOLUTION: The coupling unit 1a of a nozzle main body 1 is connected to a mold. Resin is injected into the mold in a state where a gas injecting member 2 is advanced mostly with respect to the nozzle main body 1 (on the upper side of a center line). In injecting gas, the gas injecting member 2 is retreated with respect to the nozzle main body 1 while the space between a gas passage 7 and a gas discharging port 5 is sealed by a gas reverse flow preventing seal 6. In discharging gas, the gas injecting member 2 is moved to a position, advanced slightly from the retreated position of the same, and the gas passage 7 is made to communicate with the gas discharging port 5 whereby high-pressure gas from the hollow part of a molded form is discharged out of the gas discharging port 5 through a space 8. The reverse flow of resin into the gas passage in injecting the resin can be prevented and the stay of impurities, gas and the like in the gas injecting port and the flow passage can be eliminated whereby the clogging of the gas injecting port can be prevented. In this case, the discharging of gas can also be effected within a short period of time. |
