Dynamics Characteristic For The Micro Rotary Inertial Piezoelectric Motor

The micro piezoelectric motor is a kind of new piezoelectric motor with rotary inertiato impact for rotation, and it has the advantages of simple structure, quick respond, withno electromagnetic interference and micro-displacement, etc. With harmonic electricalsignal, it utilized the inverse piezoelectric effect of piezoelectricity ceramic piece, and thepiezoelectric vibrator produced microscopic vibration and converted to macroscopicmotion of revolve with the inertia impulse. The electrical energy was converted to themechanical energy.A new one of micro rotary inertia piezoelectric motor was proposed and the drivingprinciple of the motor was analyzed in this paper. The dynamical model and differentialequation of piezoelectric vibrator were set up, and their free vibration natural frequenciesand modal functions were solved out, and that the effects of changing parameters onvibrator natural frequencies were analyzed. Based on the mode superposition method, theforced response equation of beam and axis with harmonic electrical signal were deduced.Using the equation, the forced responses of piezoelectric vibrator and the effects ofchanging parameters on forced responses were investigated. Results show that effects ofbeam parameters variation on the vibrating modes are obvious.The dynamical model and differential equation of piezoelectric vibrator were set upunder considering coupling vibration of the beam and axis. The free vibration naturalfrequencies of piezoelectric vibrator and effects of parameters variation on theirfrequencies are analyzed. The free vibration natural frequencies of coupling vibrationcompared to that of independent calculation, the relative deviation is calculated and effectsof piezoelectric vibrator parameters variation on relative deviation is analyzed. And theapplicable scope of the two different calculation methods is discussed.The free vibration of piezoelectric vibrator is simulated by ANSYS software andcompared with the theoretical analysis, which demonstrates the correctness of theoryanalysis. The harmonic response of piezoelectric vibrator is also analyzed and therelationship of amplitude and voltage is discussed. The structure design of micro-piezoelectric motor is finished, and the model machineis manufacture. The free vibration of piezoelectric vibrator is simulated by use ofworkbench software. The principle experiment of the micro piezoelectric motor iscompleted.