Utilization of Reluctance Electromagnetic Force of Inner-Mover-Type Rotary-Linear Motor

A multiple-degree-of-freedom (multi-DOF) motor can constitute small-sized and lightweight systems capable of performing complicated motions. Furthermore, the prospects for applications to industrial instruments via a direct drive are promising. This study aimed to develop practical multi-DOF motors capable of performing high-power rotary and linear motions using conventional three-phase inverters. A motor that performs rotary and linear motions is proposed. First, a method is presented for installing a salient pole on a needle with magnets. The method facilitates the use of soft magnetic materials with low eddy-current loss as iron cores. This study demonstrated the effectiveness of the salient pole for increasing the electromagnetic force. The model is used to explain the interactive magnetic interference generated by the armature currents for rotational and translation motions.