INJECTION MOLD HAVING STRUCTURE FOR TREATING INNER UNDERCUT WITH CIRCLE SHAPE AND METHOD FOR EJECTING INJECTION MOLDED PRODUCT THEREOF

摘要

PURPOSE: An injection mold having a structure of treating an inner circular undercut and a molded article ejection method are provided to reduce a working time without an additional process because a plurality of molds for an undercut is not manufactured. CONSTITUTION: An injection mold having a structure of treating an inner circular undercut comprises a cavity plate(10), a core plate(20), an eject plate(30), an insert core(50), and a plurality of lift cores(60). The cavity plate comprises a cavity(11) inside. The cavity plate forms an injection mold having an under cut. The core plate closely or separately moves from the cavity plate. The eject plate moves up and down in the lower part of the core plate. The insert core is installed inside the core plate, and the cross section of the insert core is gradually reduced. A plurality of the lift cores is slid along the guide surface(21) of the core plate. The upper ends of the lift cores are extended toward the injection mold. The lower ends of the lift cores are inclined to be fixed to the eject plate.