Patent ID: 7758328

Claim:
An injection molding machine having a function for monitoring screw rotating torques, comprising: measuring means for measuring screw rotation speeds and screw rotating torques at predetermined time or distance intervals as the screw moves for metering; storage means for storing the screw rotation speeds and screw rotating torques measured by the measuring means; determining means for determining a maximum screw rotating torque at each screw rotation speed by substituting the screw rotation speeds and screw rotating torques stored in the storage means into a previously-assumed function; allowable upper limit setting means for setting an allowable upper limit of screw rotating torque for each screw rotation speed on the basis of the maximum screw rotating torque determined by the determining means; and screw rotation stopping/changing means for stopping or changing the screw rotating operation when a screw rotating torque exceeding the allowable upper limit is detected during metering after the allowable upper limit is set.