| 摘要 |
PURPOSE:To make the filling amount of resin constant at every shots, by a method wherein the switching of the title molder is controlled by a correcting value obtained from the detecting value of the position of a screw immediately before starting injection and the memorized value of the position of the screw immediately before starting injection upon previous shot. CONSTITUTION:The actual position of a screw 2 is detected by a position detector 4 and a detected value upon outputting an injection starting signal 5 is given to a relational operator 7 through an amplifier 9. This value is memorized simultaneously into a memory 6 as the position of the screw immediately before starting the injection of the latest short. The detected value of the position of the screw immediately before starting the injection of the shot is compared with the memorized value of the position of the screw immediately before starting the injection of previous shot, which is in the memory 6'. Then, a difference DELTAS is outputted to an adding and subtracting opera tor 8 to add (or subtract) respective filling speeds and the switching position set value of a pressure keeping switch ing position setter 10 with the difference DELTAS to correct the set value. Subsequently, a control signal is sent by the adding and subtracting operator 8 to a pressure control valve 11 or a flow amount control valve 12 through the amplifier 9' whereby the filling speed and the pressure keeping switching may be controlled. |
