| 摘要 |
PURPOSE: To enable resin to be separated from the gate by providing a gate communicating with the outside on the tip end of an injection mandrel via a resin passage being coupled to the vertical resin passage, and an injecting molten resin from the other end of a hot runner to the inner surface of a joint. CONSTITUTION: A molten resin is injected in the cavity through the vertical resin passage 6 of a hot runner 11, the resin passage 12 of the tip end of an infection mandrel, and gate 8. Then, after the lapse of a predetermined cooling time, both the mandrels 3, 4 are removed from both the opening of a joint The hot runner 11 is electrified, as a matter of course, during the period of an injection molding process and cooling process from the initial stage of the infection molding process, resulting in heating of the vertical resin passage 6. Accordingly, the sprue 10 comprising the vertical resin passage 6 and resin passage 12 can be maintained in a molten state, and as the injection mandrel 4 is removed, the sprue 10 can be separated from the gate 8. |
