数控机床床身结构改进与受迫振动仿真验证  

Structural Improvement of CNC Machine Bed and Verification with Forced Vibration Simulation

作　　者：甘建峰 盘继松 GAN Jian-feng;PAN Ji-song(Shenzhen Institute of Artificial Intelligence and Robotics,The Chinese University of Hong Kong(Shenzhen),Shenzhen 518172)

机构地区：[1]香港中文大学(深圳)深圳市人工智能与机器人研究院,广东深圳518172

出　　处：《制造业自动化》2025年第2期180-188,共9页Manufacturing Automation

基　　金：深圳市技术攻关重点项目(JSGG20210420091602007)。

摘　　要：高精度数控机床是制造高附加值零件的重要平台,这种机床具有很高的重复定位精度和自动化程度。但是机床加工颤振严重限制了这种技术的应用范围。为了抑制颤振现象,现有研究聚焦刀具-夹具-主轴系统的高频振动,忽视了机床结构低频振动对颤振的贡献。针对该问题,结合机床低频振型分析与振动仿真算法,研究机床的加工稳定性。首先在低频段内对机床进行实验模态分析,据此改造机床结构。使用改进前后的几何模型进行有限元仿真,获取系统模态参数。建立结构动力学模型并进行受迫振动仿真,比较系统受迫振动以观察稳定性。结果表明,改进后的机床固有频率和阻尼比均有所提升,机床振动幅值降低为原始情况的30%。机床结构改造对加工颤振的抑制效果显著。CNC machine tool with high precision is an essential platform for manufacturing high value-added parts,exhibiting considerable repeatability and automaticity.However,chatter during manufacturing has seriously restricted the application of this technology.When suppressing the machining chatter,existing studies focus mainly on the high-frequency vibration on the tool-holder-spindle system,ignoring the low-frequency oscillation contributed by the machine tool.To address this issue,this paper investigates the manufacturing dynamic properties of machine tool by integrating the low-frequency mode shape analysis and the forced vibration simulation.Executing experimental modal analysis in low-frequency band of the machine tool to improve its structure,the original and modified structures are then processed by FEM to capture their modal parameters.Establishing structural dynamics models for the machine tools while simulating their forced vibrations,the outcomes are compared to observe their stabilities.The results show that the natural frequency and damping ratio of the new machine tool are all improved,whereas the vibration amplitude is reduced to 30% of the original situation,indicating that the proposed structure modification strategies of the machine tool have a significant effect on chatter suppression.

关 键 词：实验模态分析 结构动力学 机床结构改进 有限元分析 

分 类 号：TH122[机械工程—机械设计及理论] TH16