| 摘要 |
PURPOSE: A mold for injection-molding a pillar-shaped product is provided to enable the injection-molding a pillar-shaped product in which the center portion thereof has a smaller diameter than the top and bottom portions thereof. CONSTITUTION: A mold for injection-molding a pillar-shaped product comprises an upper core (12), a lower core (20), a resin injection nozzle (15), a piston (30), and a pneumatic cylinder. The resin injection nozzle injects a molten resin to a cavity. The piston linearly reciprocates between first and second positions. The first portion is contiguous to the resin injection nozzle, and the second portion is relatively separated from the resin injection nozzle. The pneumatic cylinder operates the piston. When the piston is located at the first position, the molten resin is injected from the resin injection nozzle, and the piston is moved to the second position. |
