基于Ansys Workbench的CJ190Z4机床主轴实验模型振动力学分析

Vibration Dynamics Analysis of CJ190Z4 Machine Tool Spindle Experimental Model Based on Ansys Workbench

目的研究CJ190Z4机床主轴模型机壳和主轴的动静态特性,得到主轴前6阶固有频率,振型和变形应力等,确定主轴前端及中端位移-频率关系和相位角-频率关系.方法利用Solidworks建立了CJ190Z4机床主轴模型的三维实体模型,将实验模型分为主轴和机壳两个子单元,运用Ansys Workbench有限元分析软件,对CJ190Z4机床主轴系统进行静力和动态分析,在此基础上进行谐响应分析,通过实测得到实验模型的刚体振动模态.结果不同温度下的主轴的固有频率不同,20℃下的前3阶固有频率分别为151.1 Hz,1 152.9 Hz,2 157.3 Hz,机壳单元的固有频率最小为255.15 Hz.主轴的1阶临界转速n=69 066 r/min,远大于主轴的最高工作转速3 000 r/min,主轴能有效地避免共振发生,保证了主轴的加工精度.主轴最大位移量是4.1μm,最大应力是19.5 MPa.固有频率随温度升高而降低.结论提高主轴的刚度和阻尼,可以有效减小振动变形,避免共振现象的发生;提高机壳单元的1阶固有频率或加设阻尼抑制机壳单元1阶共振,应加强机壳单元基础板的抗弯刚度.

To study the dynamic and static characteristics of the chassis and the spindle of the CJ190Z4 machine tool,the natural frequency,the vibration mode and the deformation stress of the first 6 orders of the main shaft are obtained.The relationship between the front and end displacement-frequency relationship and the phase angle-frequency relationship is obtained.The three-dimensional solid model of CJ190Z4 machine tool spindle model was established by Solidworks.Theexperimental model was divided into two sub-units of spindle and chassis.Ansys Workbench finite element analysis software was used to analyze the static and dynamic analysis of CJ190Z4 machine tool spindle system.And the harmonic response of the experimental model is obtained.The natural frequencies of the main axes at different temperatures are different,and the first three natural frequencies are 151.1 Hz,1 152.9 Hz and 2 157.3 Hz at 20 ℃.The minimum natural frequency of the housing unit is 255.15 Hz.The first-order critical speed of the spindle is 69 066 r/min,which is far greater than the maximum working speed of the spindle 3 000 r/min,which indicates that the spindle can effectively avoid the resonance area and ensure the machining precision of the spindle.The maximum displacement of the spindle is 4.1 μm,the maximum stress is 19.5 MPa.The natural frequency decreases with increasing temperature.The bending stiffness of the base plate of the chassis unit should be strengthened to improve the first order natural frequency of the casing element or the first order resonance of the damping suppression shell element.Improve the stiffness and damping of the spindle,can effectively reduce the vibration deformation,to avoid the occurrence of resonance phenomenon.