Research On A Ultrasonic Motor Based On Longitudinal-bending Modal

A new type ultrasonic motor based on longitudinal and bending modes was proposed in thispaper,which has simple structure and high reliability,etc. The driving tips of the motor have goodconsistency because of its symmetrical structure.Firstly, the stator structure of the ultrasonic motor based on longitudinal and bending modes wasanalysed.And then the braking principle and the working principle of the motor was introduced, andthat the piezoelectric ceramics was selected and designed. The stator model was designed byANSYS9.0, the sensitive parameters of resonance frequency of the stator were gained by modalanalysis,the longitudinal and bending resonance frequency of stator was degenerated,and the resultof transient analysis shows that the trajectory of node on driving tips is nearly an ellipse. And thedriving tips trajectory of the stator was analyzed under different conditions,obtained the influence ofmotor driving tips trajectory under different voltge and phase.Secondly, based on the stator structure parameters, all the structure of the ultrasonic motor wasdesigned, and the rotor components, preloading components, supporting device and the clampingstructure of the stator was analyzed.The strength of motor shell and rotor was analyzed by FEM.Finally, based on the analysis of theory, the prototype is designed.Experiment platform formeasuring mechanical output characteristics was built. The stator modal was tested,and the mode ofthe stator was repaired, the longitudinal and bending resonance frequency of stator was degenerated.The mechanical output characteristic is no-load speed of96r/min and maximum torque of3.8N·m..