For use as a scroll pump driver, we are developing a scroll actuator whose movement is restricted in orbital motion without autorotating. There are few actual examples of such actuators, and use of a computed simulation is an effective method for analyzing the motion characteristics to obtain the optimum structure. Analysis using conventional methods, however, is extremely difficult because the actuator’s movement is orbital motion only with its autorotation restrained. For analyzing the actuator, we developed a method that automatically generates an arbitrary meshes using prepared four mesh division diagrams corresponding to different rotor positions.

This paper describes details of this method and its application to a reluctance structure scroll actuator in which the dynamic characteristics and the static torque were compared with the measured results in order to verify the appropriateness of the method. The paper also outlines the analysis of a high-speed rotation PM disc structure scroll actuator that was carried for performance comparison with the reluctance structure scroll actuator in terms of static torque, dynamic torque, and output characteristics. The results appear to indicate that the reluctance structure can achieve high torque in the low-speed range, and the PM disc structure on the other hand enables high-speed rotation while its torque is low.