| 摘要 |
PURPOSE:To perform swiftly changes of resin and color with a small quantity of the resin without wasting the resin, by moving a check ring forcibly by putting a resin flow into disorder and giving a shock by repeating an advance and a retreat of a screw in a short period of time. CONSTITUTION:Old resin left behind within a cylinder 3 is removed by repeating a turning of a screw and injection. A hopper is filled with fresh resin, the screw 7 is made to advance 7 by a distance l1 and retreat by a distance l2 (l1 is larger than l2), a plurality of times of which is repeated in a short period of time, plasticization is performed by turning the screw again when the screw arrives at the limit in advancement and similar process is repeated. As a resin flow is put out of order and a check ring 5 advances and retreats forcibly, changes of the resin and a color can be performed swiftly with a smaller quantity of the resin than usual. |
