| 摘要 |
PROBLEM TO BE SOLVED: To prevent contact between a stretch rod and a preform during the blow molding process.SOLUTION: There is provided a blow molding apparatus which comprises: a blow mold; a seal mechanism air-tightly mounted on an opening of a preform; a stretch rod for stretching the preform; first air supply means for supplying a first gas in response to the start of the stretching of the preform by the stretch rod; second gas supply means for supplying a second gas whose pressure is higher than that of the first gas before and after the completion of the stretching of the preform by the stretch rod; and auxiliary gas supply means for supplying an auxiliary gas with a gas pressure lower than that of the first gas in the preform before the stretching of the preform by the stretch rod and before supplying the first gas. |
