| 摘要 |
The invention relates to a plasticising and injecting device for a moulding by plastic injection machine comprising a plasticising screw (8) rotationally driven in a plasticising cylinder (9), a melting chamber (13) arranged upstream the plasticising screw (8) for intermediate storage of molten plastic and an injection cylinder (14) which is arranged downstream the melting chamber (13) and provided with an injection chamber (12) in which an injection piston (3) carries out a reciprocating motion. The injection piston (3) and the plasticising screw (8) are coaxially arranged in such a way that they are displaceable with respect to each other. The inventive plasticising and injecting device is characterised in that the injection piston (3) is provided with an internal part (1) and an external part (2, 25) which are alternatingly movable between an open position, when the a plastic melt flows from the melting chamber (13) towards the injection chamber (12), and a closed position when the melting chamber (13) and the injection chamber (12) are tightly closed with respect to each other. |
