Research On Corrugated Compound Screw Type Piezoelectric Actuator

The piezoelectric actuator has the advantages of simple structure, easy miniaturization, fast frequency response, high torque, no electromagnetic interference as well as power self locking and so on. Piezoelectric actuator utilize the converse piezoelectric effect and the friction coupling operation of the screw/nut to perform the enery conversion between the electric energy and the mechanical energy. It is particularly suitable for miniaturization driving equipments and precision positioning devices, and it has broad prospects,especially in the fields of aerospace, medical, micro-electromechanical systems(MEMS) and some sensitive to magnetic fields and high precision positioning fields.In order to improve the mechanical performance and energy transmission efficiency of piezoelectric actuator, a screw piezoelectric actuator using bending vibration transducer is proposed. Firstly, the structure and operating principle of screw piezoelectric actuator using bending vibration transducer was introduced,including the vibration modes of piezoelectric elements and the analysis of the actuator working process, and the transducer end surface of a particle trajectory are analyzed.Based on the size parameters by theoretical analysis, the finite element calculation model of the transducer structure was established with the ANSYS finite element analysis software, and its modal analysis and harmonic response analysis are carried on later. The operating mode and resonance frequency of the transducer was determined through modal analysis, the influence rules of the transducer structural parameters on resonant frequency and resonant amplitude were obtained through harmonic response analysis.Finally, the prototype actuator and power supply were manufactured based on the structural parameters of the actuator, through specific experimental test data show that the theoretical analysis and simulation analysis is the existence of difference. The experimental results show that the maximum no-load speedof the actuator achieves 0.62mm/s and the largest output force achieves 1.8N at the case of the operation voltage is 300 V and the driving frequency is 9.5kHz.