| 摘要 |
A method of injecting molten plastic or aluminum material into a cavity defined within a mold to form a desired part shape is provided. The method includes: (a) providing pressurized gas in the mold cavity prior to injection of molten material into the cavity; (b) generating a melt pressure sufficient to inject the molten material into the cavity; and (c) providing a closed loop controller to maintain a controllable difference between the melt pressure and the pressure of gas in the cavity throughout a substantial portion of a period of time during which molten material is being injected into the cavity, the difference being sufficient to inject molten material into the cavity in a manner to improve the conditions under which the material solidifies. By preloading the system with static pressure, conditions are created which allow generation, measurement and real time control of pressure difference profiles during transition of the melt throughout the injection cycle. |
