Research On A Piezoelectric Harmonic Motor With Ultrasonic Transducer Wave Generator

In order to meet the requirement of high torque at low speed micro special motorin aviation, aerospace, precision instruments and other areas.Comprehensive thetechnology of ultrasonic motor and harmonic drive,a new kind of piezoelectricharmonic motor with ultrasonic transducer wave generator is proposed, designed andanalysis in this paper.Firstly, select the design proposal of piezoelectric harmonic motor.Piezoelectricceramic stack wave generator and ultrasonic transducer wave generator these twotype of driver is proposed, after the introduce of structure and layout of piezoelectricharmonic motor, compare these two drivers comprehensive, chose the piezoelectricharmonic motor with ultrasonic transducer wave generator.Secondly, design and analyze the ultrasonic transducer which is the driver ofpiezoelectric harmonic motor.Introduce the design theory of ultrasonic transducer andsolid horn briefly, based on these theory the secondary cone solid horn ultrasonictransducer is designed, get its longitudinal vibration resonance frequency andvibration mode from modal analysis, verify the output displacement of ultrasonictransducer is largest in resonance frequency by doing harmonic response analysis, theresult of transient analysis shows the output displacement in the front of ultrasonictransducer is80m when the input voltage is sinusoidal with resonant frequency and500v voltage.Thirdly, the design and analyze of displacement amplification mechanism.Design the secondary leveraged double circular blade elastic displacementamplification mechanism in order to further enlarge the output displacement ofultrasonic transducer. Chose the appropriatesize parameters for the optimizationdesign of displacement amplification mechanism from the analyzing result of themaximum equivalent stress, maximum strain and actual magnification time changerule when the size parameters change, verify whether the output displacement ofdisplacement amplification mechanism satisfy the demand of flex spline deformation by analyze the stress and strain distribution of flex spline and the actual amplify timeof displacement amplification mechanism.Finally, the over-all structure design of piezoelectric harmonic motor with transducerwave generator. It composed by transducer wave generator, flex spline, circular splineand shell etc. the wave generator composed by six secondary solid horn ultrasonictransducer which share one hexagon octahedron as back shroud and six secondaryleverage displacement amplification mechanism. Get the appropriate dimensionparameters of flex spline from analyze the stress and strain change rule when themain dimension of flex spline change, based on this result complete the over-allstructure design of piezoelectric harmonic motor.