Research Of The Thinned Piezoelectric Motor

With the development of robot technology and aerospace engineering, kindsof ultrasonic motors are produced because traditional electromagnetic motors arerestricted. For bulk mass, the current traveling wave type ultrasonic motor can notwork in some specific situations. In the paper, a new ultrasonic motor which hasstructure of thin, small size and a certain driving torque is designed.In the paper, the work content consists of the vibration mechanism analysis ofvibrator, the design of vibrator structure and the design of the motor structure, asfollows.Firstly, the principle of elliptical vibration trajectory generated by thinvibrator was analyzed. The dynamic model of piezoelectric vibrator is establishedby analyzing knowledge of mechanical and piezoelectric. Mechanism of modeconversion is obtained by simulating numerical value and analyzing influence onmode conversion by layout form of piezoelectric ceramic. The natural frequenciesof beam of piezoelectric oscillator and driving lever are gotten by partition methodand characteristic parameters of mode conversion are gotten.Secondly, the whole structure of piezoelectric vibrator is designed. Theinfluence on resonant frequency of vibrator by each parameter is analyzed, whichconsists of beam of piezoelectric oscillator and driving lever. And these lay afoundation for simplification of vibrator modal. The influences on the amplitude ofvibrator by the clamping way and on the vibration trajectory by driver interface ofdriving lever are analyzed. It is analyzed that different excitation conditionsinfluence the vibration amplitude of vibrator.Thirdly, two pre-pressure applied schemes of motor are designed and theadvantages and disadvantages of different schemes are analyzed and compared.Because of the advantages of simple structure and easy to adjust the pressure,scheme of axial loading is chosen to manufacture model machine and doexperiment.Finally, the performance of the motor is tested. The motor which is designedin the paper has the advantages of simple structure, rapid response and self-lock.The cause of difference between experimental data and theory is analyzed. Contactmodel of the stator and rotor is analyzed which provides guidance for the design offriction material.