PURPOSE: To increase molding range, to control cavity space arbitrarily and to eliminate wasteful operations by compressing or expanding resin by actuating core mold which is movably incorporated in molds through a movable platen.
CONSTITUTION: After clamping molds, cavities of molds 31, 32 are charged with resin 33 through an injection machine. At this time, a core 32b is positioned above the movable platen to expand the cavity volume. After completion of charging with resin, the movable platen 8 is moved to the side of a table 1 to move the core 32b downward and to compress resin 33. Then, movable platen backward position controller is driven to remove a resistor 20 and to release the movable platen 8. A hydraulic cylinder 27 is driven to move the core 31b upward and to release a molded piece 34 from the molds. The cavity volume can be changed freely by adjusting the positions of the core 31b, 32b. Charged resin 33 moves the core 32b upward to enlarge the cavity volume and also expand resin in the molds.
MATSUI TOKUO
NISHIZAWA KESAJI
