METHOD OF MOLDING THERMOPLASTIC RESIN CONTAINER AND MOLDS THEREFOR

摘要

PURPOSE:To mold a container having no flaw on the surface by a method wherein heated and softened sheet is held by clamps ad pushed by a small plug into the cavity of a female mold and then compressed air is injected into the plug and at the same time air in the cavity of the bottom force is sucked. CONSTITUTION:The thermoplastic sheet S heated to the temperature capable of thermal molding is put between split mold holds 3 and clamps 4, a bottom force 1 is moved toward the sheet, the split mold 2 is closed by pressing the split mold 2 against the hold 3 and the clamp 4 are moved to hold the sheet S by the holds 3 and the clamps 4. A protrusion 5 smaller than the cavity 6 of the bottom force 1 is inserted into the cavity 6 to push and strength the sheet S and then compressed air is injected into the cavity and the air between the sheet S and the bottom force 1 is sucked from the exhaust port 7 of the bottom force to mold a container by sticking the sheet S closely to the bottom force 1. After completion of molding, the split mold is opened in the form of a petal to take the container out of the female mold 1 and then to be trimmed.