| 摘要 |
PURPOSE:To prevent molded defectives from occurring and to improve productivity by a method wherein after synthetic resin is injection-molded to form a cover portion covering the outside of a follower magnet, synthetic resin is injection-molded in order to cover portions that was not covered. CONSTITUTION:A cylindrical follower magnet 6 is fitted to a projecting rod A2 of an injection mold A and one end of the magnet is abutted on the injection mold A through a cylindrical spacer to inject and mold the synthetic resin to form a cover portion of the outside of the follower magnet 6. Then, the portion that was not covered with synthetic resin in the abovementioned process for the follower magent 6 put in the space formed between opposite injection molds C, D and an impeller P2 body having one end covered and the other end provided with blades are formed by injecting and molding synthetic resin. The injection mold A can be manufactured easily by this method and defective injection moldings scarcely occur. |
