MOTOR-DRIVEN INJECTION DRIVE DEVICE FOR INJECTION MOLDING MACHINE

摘要

A motor-driven injection driving apparatus for an injection molding machine comprises a fixed frame 4 having an injection cylinder 8, first and second injection drive motors 7, and first and second ball screw shafts 10; first and second power transmission mechanisms 12 for transmitting the rotational forces of the first and second injection drive motors 7 to the first and second ball screw shafts 10, respectively, while reducing the speed; and a movable frame 6 provided with first and second ball screw nuts 11 threaded on the first and second ball screw shafts 10, respectively, and a screw drive motor 14 and capable of being moved in the direction of injection together with an injection screw 9. In the injection process, the movable frame 6 is moved so that a tensile force acts on the first and second ball screw shafts 10.