| 摘要 |
PURPOSE:To speedily mold resin exterior trim part, resin structural part or the like at low cost by a method wherein rubber mold, simple mold, ceramic mold or the like is employed. CONSTITUTION:In order to perform the vacuum casting, firstly, a vacuum chamber and a mold, which is placed in the vacuum chamber and heated up to the reaction temperature for vacuum casting, are provided at the lower part of an injection section. Secondly, the chamber is evacuated to 5X10<-1>Torr or less before injection. Thirdly, after the predetermined amount of material is injected, the chamber is gradually brought back to the atmospheric pressure. Concretely, agitating blades and gear pumps P1 and P2 are respectively provided to a main material liquid tank A and an assistant liquid tank B for agitation and circulation. Though the deterioration of the material may slightly develop by the circulation of the mate rial, the residual bubbles in the piping are eliminated by said circulation. Because the tanks are evacuated, while the material stands in the tanks, bubbles in the material escape from the material. In addition, valves V1 and V2 are closed during the circulation of the material. When the injection of the material is intended, the valves V1 and V2 are open to pour the liquids in the tanks A and B in a mixing part M and, after that, a valve V5 is open so as to discard the small amount of the liquid in the mixing part M in order to remove epsilon- caprolactam. Finally, the valve V5 is closed and a valve V4 is open for injecting the predeter mined amount I1 of the material into the mold in the vacuum chamber. |
