Development of ironless type surface motor

Recently, the application of multi-dimension drive systems is increasing. Generally, this drive system consists of plural motors. However, since plural motors are used for this structure, the equipment becomes large and control becomes complicated. At this laboratory, extensive research and development of a surface motor (SFM) were carried out. The structure of SFM proposed until now has arranged a square permanent magnet on a checkerboard pattern at the stator side. And, the mover consisted of an air-core coil and a back yoke. However, this structure tends to be influenced by normal-force. Moreover, the thrust force in the x direction drive and the y direction drive changes according to the coil structure. So, we propose a structure of a new ironless type SFM where the back yoke in the mover has been removed and the coil arrangement. This paper provides a comparison of the characteristics ironless type SFM.