METHOD FOR MONITORING ABNORMAL PRESSURE IN INJECTION MOLDING MACHINE DURING SCREW REVOLUTION

摘要

PURPOSE:To prevent the breaking accident of a screw or a screw cylinder and to enhance productivity in injection molding, by automatically performing each function for detecting the pressure at the inlet of a high torque motor and stopping the rotation of a screw when said pressure exceeded set monitor pressure. CONSTITUTION:Monitor pressure is present by a monitor value setting device 12 and the pressure detected by the pressure sensor 10 provided to the 'inlet' of a high torque motor 1 is compared with the monitor pressure by a comparator 11. When the detected pressure is higher than the monitor pressure, a monitor pressure exceeding signal is sent to a molding machine controller 7 from the comparator 11 and a circuit automatically cutting off a hydraulic pressure source is automatically constituted to instananeously stop the rotation of the screw and an alarm emitting measure is taken. By this method, the cold start of the rotation of the screw can be perfectly prevented and the breakage and destruction of principal parts such as the screw or the cylinder are eliminated and the shortening of a molding rising time can be attained.