METHOD AND APPARATUS FOR COMPRESSION MOLDING OF PLASTIC ARTICLE

摘要

PROBLEM TO BE SOLVED: To perform compression molding so as to conform to the variable charging of a material without exerting effect on the axial direction relation between the male and female parts of a mold. SOLUTION: A plastic article compression molding method and apparatus are equipped with assembled molds 27, 28 cooperating with each other and a first mold moves a core and a core sleeve to bring them into engagement with the cavity mold of a second mold and an actuator is provided between the first mold and a fixed upper cam. The second mold supports the cavity mold and has the actuator 52 related to a lower fixed cam 31. The nitrogen cylinder in the second mold controls compression molding force. In a pref. form, plural sets of molds are provided to the rotary turret 22 supported by a central column 21 so as to leave an interval in a circumferential direction. A common manifold supplies pressure accurately controlled by the nitrogen cylinder. A control unit monitoring the pressure and changing the same is provided.