Motor drive apparatus for an injection molding machine

Abstract

A motor drive apparatus is provided in an injection molding machine in order to supply electrical energy to a motor. The motor drive apparatus includes an electricity accumulation unit for accumulating electrical energy; and an electricity accumulation circuit for accumulating in the electricity accumulation unit electrical energy regenerated from the motor during a deceleration period of the motor and for supplying the electrical energy accumulated in the electricity accumulation unit to the motor during an acceleration period of the motor. By virtue of the above-described structure, when a heavy member such as a screw of an injection apparatus or a movable platen of a mold clamping apparatus is moved at high speed in each molding cycle, at the beginning of movement or during an acceleration period of the motor, the electricity accumulation circuit adds the electrical energy accumulated in the accumulation unit to electrical energy that is supplied from a power source to the motor, and during a deceleration period of the motor, electrical energy regenerated from the motor is accumulated in the accumulation unit.

Dependencies are inferred from the claim text.