| 摘要 |
PURPOSE:To make it possible to prepare a cylindrical molding having a bellows part, by constituting an injection molding part and an apparatus for preventing excess expansion of a bellows molding located below the injection molding part when the bellows molding is released from a mold. CONSTITUTION:After a bellows molding is molded, a coremain body 6 moves to a movable side with the mold opening and a released part is located below it. An inner cylinder 14 moves upwards with a rise of a outer cylinder 13 and surrounds the core main body 6 attached with a bellows molding 18. At the same time, a cylindrical hollow part at the low end of the molding 18 is clamped by a rise of a clamp 15 and is tightly closed by a rise of a supporting device 16 of the clamp. Compressed air is forced into the molding 18 to expand it and the molding 18 is released successively from the lower part and separated from the core main body 6 by lowering the clamp 15 with the supporting device 16. |
