| 摘要 |
PURPOSE:To prepare a reel hub excellent in roundness, by molding an intermediate ring shaped part surrounded by an inner annular part having a shaft hole and an outer annular part coming to the outer peripheral surface of the reel hub while simultaneously molding the inner annular part and the outer annular part to the inside and outside of said intermediate ring shaped part. CONSTITUTION:An intermediate ring shaped part 5 surrounded by an inner annular part 3 having a shaft hole 2 through which the reel shaft of a tape recorder is inserted and an outer annular part 4 coming to the outer peripheral surface of a reel hub 1 is at first molded by an injection molding method. In the next step, the intermediate ring shaped part 5 is withdrawn from a cavity for molding the intermediate ring shaped part in a state attached to a movable side mold and, after the movable side mold is rotated by 180 deg. around the central axial line of a mold splitting surface, the mold is closed to fit the intermediate ring shaped part in a cavity for molding the outer annular part and the inner annular part. In the next step, a resin is injected into said cavity to simultaneously mold the inner annular part 3 and the outer annular part 4 to the inside and outside of the intermediate ring shaped part 5.
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