Design Of High Power Loaded Longitudinal Vibration Tuned Ultrasonic Oscillator

The core component of power ultrasound is an ultrasonic vibrator,which is structurally divided into a transducer and a horn.Due to its excellent ultrasonic vibration characteristics,it has been widely used in processing,cleaning and medical treatment.In ultrasonic machining applications and tests,many factors such as external load change at the front end of the horn and tool wear affect the resonant frequency of the entire ultrasonic vibrator,resulting in unstable processing,resulting in reduced productivity or even stopped work.This paper studies the improvement of the performance of high-power ultrasonic vibrators and the adjustment of the resonant frequency of ultrasonic vibrators.In order to design a piezoelectric transducer with large front-to-back vibration ratio and effective electromechanical coupling coefficient,the transducer with resonant frequency of 35 kHz is designed by numerical analysis method,and the two influencing factors of material and size are used to optimize the size..Considering the influence of the front and rear end cap materials on the transducer vibration ratio and the effective electromechanical coupling coefficient,the front and rear end caps of different materials are selected to facilitate the energy transfer;while the frequency equation is satisfied,the two can be used to achieve higher values.Then,the horn connected to the front end of the transducer is designed.Finally,using ANSYS 17.0 finite element analysis software,the modal and harmonic response results of the ultrasonic oscillator are obtained through simulation.The axial amplitude and admittance map are analyzed,and the frequency simulation value and design value are obtained within the error range,which verifies the design.Feasibility.Secondly,considering the load effect,the equivalent circuit is used to analyze the influence of the inductance on the ultrasonic oscillator,and the corresponding frequency equation is derived.According to the frequency equation,the resonant frequency corresponding to the vibrator is calculated when the external matching inductance is calculated;the tuning inductance under the external load of the ultrasonic vibrator is calculated in the reverse direction.The modal and harmonic response analysis of the externally connected ultrasonic vibrator is carried out,and the maximum response curve is obtained,and compared with the theoretical frequency value to verify the correctness of the matching theory.Finally,the rationality of the design dimension of the ultrasonic vibrator,the frequency variation of the external inductor of the ultrasonic vibrator and the adjustment effect of the matching inductor on the resonant frequency of the ultrasonic vibrator are verified by three sets of experiments.The experimental results show that the harmonic oscillator has a good frequency.The adjustment performance can be used in tests such as power ultrasonic processing and cavitation.