KDP晶体精密机床静动态特性及实验模态分析
2020-10-23
作者：路文文1，戚泽海1，关佳亮2，赵显辉1，徐青山1
单位：1首都航天机械有限公司；2北京工业大学
摘要：为保证KDP晶体加工中表面粗糙度、表面波纹度和透射波前三项技术指标，需解决KDP晶体单点金刚石飞刀切削超精密机床加工稳定性和精度差的问题。通过ANSYS Workbench软件对机床进行静态分析，利用有限元模态分析得到机床整机的变形云图和振型云图，并分析了机床结构的固有频率与振型之间的关系。结果表明，主轴箱为机床的薄弱环节，需改变主轴箱内部筋板结构及提高导轨结合面的接触刚度。基于LMS SCADAS进行的机床整机实验模态分析结果与有限元分析之间的最大误差为10.75Hz，验证了有限元分析结果的正确性，并为下一步机床的优化设计奠定了基础。
关键词：KDP晶体；静动态特性；实验模态分析
中图分类号：TG502；TH161文献标志码：ADOI：10.3969/j.issn.1000-7008.2020.08.013
Static and Dynamic Characteristics and Experimental Modal Analysis
of KDP Crystal in Precision Machine
Lu Wenwen，Qi Zehai，Guan Jialiang，Zhao Xianhui，Xu Qingshan
Abstract:In order to ensure three technical index of surface roughness，surface waviness and transmitted wavefront in the process of machining KDP crystal，it is imperative to solve the problem of machining stability and accuracy of KDP crystal in single point diamond knife cutting ultraprecision machine.The static analysis of machine tool is conducted based by ANSYS Workbench software.Deformation nephogram and vibration types nephogram of machine tool is acquired by modal analysis method of finite element，and the relationship between the above structure modal frequencies and mode shapes is analyzed．The results show that the spindle box is the weak link of the machine tool.Thus，it is necessary to change the inside stiffened plate and improve the contact stiffness of the joint surface of the main shaft box.The experimental modal analysis of the whole machine based on LMS SCADAS is carried out，and the maximum error between the analysis results and the finite element analysis is 10.75Hz，which verifies the correctness of the finite element analysis results.And the results lay a foundation for optimal design of machine tool for the next step.
Keywords:KDP crystal；static and dynamic characteristics；experimental modal analysis