Development of an Innovative 3D Ultrasonic Vibrator for Ultrasonic Vibration Cutting

An innovative 3D (three-dimensional) ultrasonic vibrator using one longitudinal vibration mode and two bending resonant vibration modes is presented in this paper. A sandwich structure is used to ensure the high working frequency and high stiffness. The electromechanical equivalent model of the 3D ultrasonic vibrator is built to determine initial parameters of the 3D ultrasonic vibrator. Then, finite element method is used to optimize the longitudinal vibration frequency coupled with the bending vibration frequency. The simulation results show that the resonant frequency difference of longitudinal and bending vibration is around 0.067%, demonstrating the longitudinal and bending vibration modes of the 3D ultrasonic vibrator are well coupled. Thus, the 3D ultrasonic vibrator has the ability of generating 3D ultrasonic vibrations at the coupled resonant frequency.