Method of monitoring die opening force in an electric injection molding machine

Abstract

An object of the present invention is to provide a method of preventing the failure of dies to open because of insufficient die opening force in an electric injection molding machine. A stationary die is attached to a stationary platen, whereas a movable die is attached to the front surface of a movable platen. The movable platen moves along the clamping and unclamping operation by a toggle mechanism. The toggle mechanism is expanded or contracted by a servo motor via a crosshead. A control section controls the operation of the servomotor by sending data of the crosshead position as a feed-back signal. A comparison unit compares a measured torque value of the servomotor with the upper limit value previously set and displays a warning on a display unit when the measured value exceeds the upper limit.

Dependencies are inferred from the claim text.