Two-Phase Piezoelectric Motor Using a Multiple-Tube Structure Actuator

Abstract

The construction of piezoelectric motors using multiple piezoelectric tubes is proposed in this paper. The static and dynamic characteristics of an eight-tube actuator are studied. The formulas of the bending deflection, moment, and resonant frequency are given. A prototype two-phase traveling wave piezoelectric motor using such a structure is studied. The stator that is composed of eight piezoelectric tubes produces a wobbling motion when excited in a certain pattern. Both the static and dynamic characteristics of the stator were measured. The rotor's angular speed possesses a good linearity with the driving voltage amplitude. With a driving voltage of 200 Vp–p at 5.0 kHz, the motor can rotate at the highest angular speed of 319 rpm and produce a maximum stall torque of 1.6 mN·m. With an applied voltage of 160 Vp–p and a preload of 0.3 N, the motor's working efficiency reached about 12%.