Stepping motor and a method of driving the same

Abstract

According to the invention, there is provided a stepping motor comprising a laminate type torsion actuator having a pair of cylindrical outer peripheries to be torsionally displaced relative to each other, a cylindrical fixed member surrounding said laminate type torsion actuator with certain space therebetween, first longitudinally vibrating elements placed between said fixed member and one of the cylindrical outer peripheries of said laminate type torsion actuator for selectively connecting or separating the fixed member and the torsion actuator through its elongation or contraction, second longitudinally vibrating elements placed between said fixed member and the other cylindrical peripheries of said torsion actuator with certain space therebetween for selectively connecting or separating the fixed member and the torsion actuator through its elongation or contraction with a phase inverse to that of the first elements. Such a stepping motor allows fine control of its rotary speed and position and large torque.