| 摘要 |
PURPOSE:To contrive to prevent molten resin from drooling from a nozzle by a method wherein a piston means is retreated and stopped until the pressure of molten resin at the finish of metering lowers down to a certain value, which is set in advance. CONSTITUTION:The pressure of molten resin, which is stored at the tip part of a screw 2 through the rotation of the screw 2 during the plasticizing process, is detected with a sensor 5. The detected input value of the sensor 15, which is read through an analog-to-digital converter 22, is compared with the value, which is set with the setter 26 of metering resin pressure, in order to perform the metering process by feedback controlling the retreating speed of the screw 2 by means of an injection servo motor 6 so as to bring the difference between said values to zero. At the same time, the retreat position of the screw 2 is detected with a position sensor 17. The detected input value of the sensor 17, which is read through an analog-to-digital converter 23, is compared with the value, which is set with the setter 27 of metering end position, so as to stop the rotational driving motor 13 of the screw at the time when the difference between said values becomes zero. At the same time, the metering of the retreating operation of the screw 2 by the injection servo motor 6 is stopped. |
