| 摘要 |
A method and system for injection molding plastic articles which utilize a spill area (28) whose volume varies within an article-defining mold cavity (29). In one embodiment, the volume increases during introduction of pressurized gas into the mold cavity. In another embodiment, the volume of the spill area (28) varies during a plastic injection which fills the mold cavity. A core (30) reciprocally mounted within the mold cavity partially defines the variable volume of the spill area (28). An air spring (41) is utilized to control pressure on the core (30) which counters the pressure of the plastic at an end face (32) of on the core (30). In one embodiment, the end face of the core is non-flat to create an area where fluid plastic can exert pressure against the end face within the mold cavity during plastic injection and/or during introduction of pressurized gas. |
