Research On Fast Servo Tool Based On Piezoelectric Ceramics

The microstructure surface can realize functions such as integration and wavefront conversion which are difficult to be completed by common components,and has the characteristics of small size,high precision,and rich functions.Ultra-precision fast-blade servo technology has become one of the most effective methods for processing microstructured surfaces due to its high precision and high efficiency.However,the contradiction between the processing frequency and the processing stroke limits the further development of the fast knife servo technology.Therefore,this paper designs and develops a fast tool servo by introducing flat flexible hinge,so that the fast tool servo can also have a certain processing stroke under high frequency vibration.In this paper,according to the specific parameters of the fast tool servo system,the technical index requirements of the tool holder mechanism are clarified.By summarizing the driving types of the existing tool servo and combining the technical indicators,a technical route using piezoelectric ceramics as a driving device has been developed.The overall structure of the tool servo is designed by combining the flat flexible hinge and the straight circular flexible hinge.Established the mathematical model of the fast tool servo system and obtained the stiffness calculation formula,which provides a theoretical basis for further parameter optimization.Secondly,the resonant frequency and elastic resilience force of the fast tool servo system proposed in this paper are verified by theoretical analysis,and the pre-tightening force required for working is calculated.Further,the finite element analysis method is used to simulate the fast tool servo.The stiffness and stress distribution are obtained by structural static analysis.The natural frequencies are obtained by modal analysis.The relationship between the fast tool servo displacement and the vibration frequency is obtained by using the harmonic response analysis.Finally,the main performance of the fast tool servo was tested by experiments.Through the stiffness test,the actual stiffness of the fast tool servo is obtained.Comparing it with theoretical stiffness and simulation stiffness,the source of error is analyzed.Through the displacement test,the no-load displacement of the piezoelectric ceramic and the actual displacement of the fast tool servo are obtained.Comparing them,the displacement loss was about 18.3%.The actual performance of the tool holder was verified by dynamic performance testing.