| 摘要 |
PURPOSE:To improve the degree of freedom of controlling a temperature gradient in the heating cylinder by a method wherein the screw heating cylinder is partitioned into a plurality of zones and respective zones are provided with a plurality of heaters while the heating temperatures of the heaters are set independently. CONSTITUTION:The screw heating cylinder 1 is partitioned into three zones A, B, C axially and respective zones are provided with a plurality of heaters 2, 3, 4. The material resin in the screw heating cylinder 1 is melted by the heaters 2, 3, 4. In respective zones A, B, C, the outer peripheral surface of the screw heating cylinder 1 between the heater 2 and the heater 3 is provided with a temperature sensor 5 and respective control circuits 6 control respective heaters 2, 3, 4. According to this constitution, the temperature gradient of the screw heating cylinder 1 may be closed to a desired gradient as much as possible. On the other hand, the degree of freedom of control may be increased and a temperature gradient, shown by the diagrams (a), (b), (c), may be obtained in accordance with the supplying amount of the material resin. |
