Characteristic Analysis And Application Technology Study Of Circular Power Diaphragm Type Piezoelectric Vibrator

Piezoelectric driver is a new type of driver and controller which usespiezoelectric material as the core component，uses mechanical structure as the mainenergy conversion method and aims to provide motion driver and control ability.Piezoelectric material is one of the recently developed and gradually improvedfunction materials which of the performance has been improved greatly in the recentyears. The piezoelectric vibrator which consist of it has the characteristics of highprecision of deformation， high speed， large thrust， small volume and noneelectromagnetic interference，and the deformation accuracy can reach micron-ornano-phase， so it is often used as the driving source with high-speed andhigh-accuracy. Nowadays, through the performance analysis and the study ofapplication status of piezoelectric vibrator of abroad and domestic，it is can be foundthat the systematic researches of the diaphragm type piezoelectric vibrator with highoutput power, high rigidity, large load bearing are lack and the applications of it arealso rarely seen.This paper combines the research requirement of "design theory and keytechnology research of piezoelectric driving type fluid dynamic coupling rheiddriver(NO.51405189)" by national natural science fund and "research of a newtype high-frequency fatigue testing machine（No.20140101078JC）"by basicprogram of science and technology development plan in Jilin Province.and pro-posed a circular piezoelectric vibrator which is pasted and made by both piezoelectric crystal and also can be used to high power output. And then the systematic research about the related theories of the piezoelectric vibrator of circularpower and diaphragm type (hereinafter referred to as the circular piezoelectricvibrator)which is used to construct the fatigue testing equipment and the piez-oelectric vibration feeder system has been made and the dynamic analysis，simulation analysis and experimental researches are conducted. The main researchcontents are as follows:1、On the basis of reading large amount of papers，the application types and status of piezoelectric vibrators are analyzed，the meaning of the characteristic andapplication research of the circular piezoelectric vibrator are pointed out.2、The Rayleigh energy method is used to modeling and analysis the circularpiezoelectric vibrator when its perimeter is fixed， and the effect law of thepiezoelectric vibrator structure parameters (the thickness ratio of metal substrate andpiezoelectric vibrator，the diameter ratio of piezoelectric vibrator and metal substrate)on the performance parameters is obtained. Then, the method in which themeasurement of the circular piezoelectric vibrator chose and fitted is provided. Usingthe impedance analyzer，the impedance character and the natural frequency of thecircular piezoelectric vibrator are obtained. Compared with the theoretical analysis，the correction and rationality of the theoretical analysis is confirmed.3、The way，method and modal of the vibration system which consists of thecircular piezoelectric vibrator are discussed. The maximum power and deformation ofthe circular piezoelectric vibrator are analyzed and the best structure parameters aredetermined. The conclusion is obtained that the thickness of the metal substrate is fargreater than that of the piezoelectric ceramic as the power output of the circularpiezoelectric vibrator. The basic modal and computation expression of the resonantsystem consisted by circular piezoelectric vibrator are given，which provided the basisfor the theoretical analysis of the system, whose excitation source is constructed bycircular piezoelectric vibrator.4、The piezoelectric fatigue testing system which uses the circular piezoelectricvibrator as the core component can realize the fatigue test and measurement onmicro-small hard-brittle materials or components under high-frequency force in thecondition of resonant status. The dynamic differential equation of the fatigue testingsystem is established based on the Newton Second Law，then the expression of naturalfrequency and dynamic load of the system can be obtained and calculated numerically.The analytic expression of stiffness of the circular piezoelectric vibrator is provided,and the effect relationships of stiffness of the circular piezoelectric vibrator on naturalfrequency and dynamic load of the resonant system are analyzed by MATLAB. Thefatigue testing system is simulated by using the finite element analysis software andthe main vibration mode of the system is obtained, and the harmonic responseanalysis of the test piece and circular piezoelectric vibration is conducted andobtained the conclusion that the fatigue testing system has the characteristic of highprecision and stable operation.5、The piezoelectric vibration feeding system is constructed, which uses the circular piezoelectric vibrator as the core component，and it can realize the pass andtransport of the light small materials under resonant status. The two-freedomsystematic dynamic modal is established, and the natural frequency and equivalentmass of the system are obtained, then the system is translated into one-freedomsystem, and the relationship between the systematic amplification, phase angle andfrequency ratio (the ratio between circular piezoelectric vibrator frequency and naturalfrequency) are obtained. Then the ratio of amplitude and dynamic force of the twovibrators and single vibrators when the system is under resonant status is derived. Theresonant system is simulated analyzed by using the finite element analysis softwareand the multiple order vibration mode of the system is received, and the mainvibration mode of the resonant system is determined when it works, then the harmonicresponse analysis on the material plate is completed, which verifies that the vibratingfeeding system, whose excitation source is constructed by circular piezoelectricvibrator, can run stably in the condition of resonant status. The formulas of the workof exciting force and the power consumed of the circular piezoelectric vibrator aredeviated, which provide a calculating method for the energy consumed of thevibrating feeding system.6、Combined with the study of the resonant system which is constructed bycircular piezoelectric vibrator，the prototypes of the fatigue test system and thevibration feeder system are trial-produced，and the researches on the two systems arecompleted individually. The natural frequency and the dynamic load of the fatigue testsystem is test. Then by comparing them with the theory value，the correctness oftheory analysis is confirmed. The structure parameters of the circular piezoelectricvibrator are analyzed at different frequencies and under different loads. Theflexural-fatigue experiment which is used LY12Aluminum as the experiment object isconducted，the S-N stress curve line is drew. The influence of the driving signal andthe structure parameters on the vibration feeder system performance is test，theoptimal structure parameters and the transporting material mass parameters isobtained. The comparative testes of the load mass and the output force of the feedersystems whose driving force are double circular piezoelectric vibrator and onecircular piezoelectric vibrator are conducted. The power consumed by the vibratingfeeder is test，the advantage of energy saving of the feeder driven by piezoelectricvibrator is confirmed.