DRIVE DEVICE FOR INJECTION MOLDING MACHINE AND MOLDING METHOD

摘要

A drive device for an injection molding machine, capable of improving response of start-up acceleration of a driven portion. The drive device has the driven portion; a transmission shaft having a screw shaft portion and an output shaft portion, relatively rotatably connected to the driven portion, and advanceably and retreatably disposed; a nut screwed on to the screw shaft portion; a motor frame mounted on a motor installation frame, a rotor installed on the output shaft portion; and a stator installed on the motor frame. Since the rotor is installed on the output shaft portion of the transmission shaft, the inner diameter of the stator can be made smaller correspondingly to make the outer diameter of the rotor smaller. This enables inertia of a drive system to be smaller, enabling acceleration of the drive system to be greater and the response of start-up acceleration of the driven portion to be higher. In addition, since rotation can be transmitted to the transmission shaft without using splines, there is no sliding resistance caused by splines.