METHOD OF MAKING POSITIONING CORRECTION ON ELECTRIC INJECTION MOLDING MACHINE.

摘要

A method of making positioning correction on an electric injection molding machine to clamp molds with a toggle mechanism or crank, which intends to eliminate waste of power to be supplied to a servomotor and overheat by locking up in an ideal state the molding machine. A load (RA) acting on the servomotor (7) for clamping molds is detected (S8) during locking-up and, when a value of said load (RA) exceeds a preset reference value (V0), a value (PM) to instruct a position of the servomotor (7) is increased or decreased in the direction for reducing the value of said load (RA) (S12, S13) in the subsequent cycle. As a result, the rotation center (Q1) of a crank (2) and both ends (Q2, Q3) of a link (3) are aligned at the time of locking-up and torque caused by reaction of mold clamping is removed from the rotation center (Q1) of the crank (2). In other words, reaction of mold clamping during locking-up is ensured even without application of driving torque by supplying current to the servomotor (7) for mold clamping. Thus, waste of electric power is prevented, a load on the mold clamping servomotor (7) is reduced, and provision of a stopper or the like for maintaining reaction of mold clamping force is needless.