METHOD AND APPARATUS FOR STRETCH BLOW MOLDING

摘要

PROBLEM TO BE SOLVED: To enable stretching blows respectively in a conformable state by simultaneously starting air blows to all preforms by operating one change-over valve so that the tip position of a stretching rod to the inner bottom surface of the preform can be set in each stretching rod. SOLUTION: A number of the preforms injection-molded simultaneously are stretched/expanded by the elongation of the stretching rod in a blow mold and blow air to mold hollow moldings. An air circuit is constituted so that the air blows of the preforms are started simultaneously by operating one change-over valve. The height position to the inner bottom surface of the preform of the stretching chip of the stretching rod from the stretching state of each preform is adjusted individually. The start of the air blow is set for the stretching rod in which the stretching chip touches the preform inner bottom surface last from the difference of the height positions. The stretching blows of all the preforms are simultaneously carried out respectively in a conformable state. COPYRIGHT: (C)2007,JPO&INPIT