Patent 7125233 was granted and assigned to Sumitomo Heavy Industries on October, 2006 by the United States Patent and Trademark Office.
An injection apparatus includes an injection frame, a stator attached to the injection frame, a rotor disposed radially inward of the stator to be rotatable relative to the stator, and a ball screw disposed radially inward of the rotor. The rotor includes a hollow and cylindrical member disposed radially outward of the ball screw, and a magnet attached to an outer circumference of the hollow and cylindrical member.