直驱机床整机刚度特性薄弱环节辨识与优化  

Identification and Optimization of Weak Links in Stiffness Characteristics of Direct-driving Machine Tools

作　　者：王家炜 于爱兵[1] 朱立志 赵家震 齐少春 叶家往 WANG Jiawei;YU Aibing;ZHU Lizhi;ZHAO Jiazhen;QI Shaochun;YE Jiawang(Faculty of Mechanical Engineering and Mechanics,Ningbo University,Ningbo Zhejiang 315211,China)

机构地区：[1]宁波大学机械工程与力学学院,浙江宁波315211

出　　处：《机械设计与研究》2024年第3期1-6,18,共7页Machine Design And Research

基　　金：宁波市科技创新重大专项(2021Z077)。

摘　　要：为提高直驱机床整机的优化效率,改善静动态性能并达到轻量化效果,提出了一种机床整机刚度特性分析指导薄弱环节改进的优化思路。基于有限元法和串联刚度场理论对三轴直驱型加工中心进行静力学分析、模态分析和谐响应分析,辨识出横梁立柱是整机静刚度以及一、二阶模态振型的最薄弱环节。采用拓扑优化、灵敏度分析、尺寸优化相结合的方法设计并得到了横梁立柱新结构。对比优化前后的横梁立柱结构及整机性能,结果表明:新型横梁立柱在x、y、z三个方向上的静力变形量分别减少27.8%、9.3%和10.3%,前二阶固有频率分别提高23.6%和11.0%,同时横梁立柱结构实现减重9.0%;直驱机床整体刚度显著提高,并且x、y、z三个方向上的最大共振峰值分别下降31.1%、22.5%、16.0%。在横梁立柱质量减轻的前提下,直驱机床整机的静动态性能显著提升。In order to improve the optimization efficiency of the direct-driving machine tool,improve the static and dynamic performance and achieve lightweighting,an optimization idea of analyzing the stiffness characteristics of the machine tool to guide the improvement of weak parts is put forward.Based on the finite element method and the series stiffness field theory,the static analysis,modal analysis and harmonious response analysis of the three-axis direct-driving machining center are carried out,and the crossbeam column is identified as the weakest link of the static stiffness and the first and second mode shapes of the entire machine.A new structure of crossbeam and column is designed and obtained using the method of topology optimization,sensitivity analysis and size optimization.Compared with the crossbeam column structure and the performance of the entire machine before and after optimization,the results show that the static deformation of the new crossbeam column in the three directions of xyz is reduced by 27.8%,9.3%and 10.3%,respectively;the first two natural frequencies are increased by 23.6%and 11.0%,respectively;and the weight reduction of the crossbeam column structure is 9.0%.The overall stffness of the direct-driving machine tool was significantly improved,and the maximum resonance peak in the three directions of xyz decreased by 31.1%,22.5%and 16.0%,respectively.Under the premise of reducing the mass of the crossbeam column,the static and dynamic performance of the direct-driving machine tool is significantly improved.

关 键 词：直驱机床 机床整机 刚度特性 薄弱环节辨识 结构优化 

分 类 号：TH122[机械工程—机械设计及理论]