New helical-shape magnetic pole design for Magnetic Lead Screw enabling structure simplification

Magnetic lead screw (MLS) is a new type of high performance linear actuator that is attractive for many potential applications. The main difficulty of the MLS technology lies in the manufacturing of its complicated helical-shape magnetic poles. Structure simplification is, therefore, quite essential in promoting the MLS technology. In this paper, a new approach is proposed for forming the required helical-shape magnetic poles in a much simpler way. It is demonstrated that the traditional ring-shape magnetic poles, by proper rotating or shaping, can well approximate the complicated helical-shape magnetic poles. The performance of the new structure is compared with a MLS with ideal helical-shape magnetic poles using 3-D finite-element analysis. Halbach and flux concentration designs using the new approach are introduced.