Design and experiment of a slender nonresonant linear piezoelectric motor based on bridge-type amplification mechanism

A miniature non-resonance type linear piezoelectric motor based on a mechanical bridge-type amplification mechanism has been developed. The slender motor measures 29 mm × 5 mm × 3.5 mm. The stator consists of a parallel bridge amplifier and two multilayer piezoelectric actuators. The working principle of the motor is analyzed, and the physical performance of the bridge amplification mechanism is obtained by a finite element analysis. A prototype of the motor is manufactured, and the model is verified by experiment, and the mechanical properties of the motor characterized. The test results show that when the phase difference between the two driving signals is 90°, the output driving force of the motor reaches its maximum. The motor speed increases linearly from 2.2 mm/s to 7.6 mm/s when the driving frequency ranges from 100 Hz to 1100 Hz under the conditions of peak driving voltage 140 V, bias voltage 70 V and holding force 2.2 N. The motor speed decreases with the increase of load. When the driving frequency is 900 Hz and the holding force is 6 N, the maximum driving force can reach 1.41 N.