| 摘要 |
An injection molding machine or extruder 10 for injecting a foamed thermoplastic material 82 into a mold 12 for forming a shaped article at a relatively low pressure. The injection molding machine comprises a barrel 20 housing a screw 22 disposed in a relatively loose clearance with respect to an inner surface 24 of the barrel. This loose clearance provides for churning a molten thermoplastic material into a foamed condition, which is then introduced into a mold. As the thermoplastic material cools, its foamed characteristic retards shrinkage of the thermoplastic material. |
