高速电主轴转子-轴承-外壳系统动力学特性研究  

Study on Dynamic Characteristics of Motorized Spindle Rotor-Bearing-Housing System

作　　者：蒋书运[1] 林圣业 JIANG Shuyun;LIN Shengye(School of Mechanical Engineering,Southeast University,Nanjing 211189)

机构地区：[1]东南大学机械工程学院,南京211189

出　　处：《机械工程学报》2021年第13期26-35,共10页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51635004、11472078)。

摘　　要：高速深孔磨削加工电主轴采用加长悬臂外壳,其在力作用下的挠性变形对电主轴的转子动力学性能的影响不可忽略,而传统电主轴转子动力学模型均将外壳简化为刚体,不能描述该类复杂结构电主轴的动力学行为。考虑外壳的挠曲变形,基于整体传递矩阵法和成对轴承分析理论,建立了电主轴转子-轴承-外壳系统动力学模型,提出了电主轴整机临界转速、电主轴轴端动态刚度的计算方法。通过算例系统地分析了电主轴外壳抗弯刚度、轴承选型等对电主轴动态特性的影响;研制了高速内圆磨削电主轴试验样机,开展了电主轴轴端动刚度的试验验证。结果表明:建立的电主轴转子-轴承-外壳系统动力学模型计算精度高,可用于深孔磨削加工电主轴的动力学特性分析;电主轴外壳悬臂端是主轴动态薄弱环节,采用非同心圆环的增强外壳能明显提升电主轴的临界转速与动态刚度;选用特轻系列轴承替代轻系列轴承,电主轴的一阶临界转速和轴端静刚度均有所增大。Long-cantilever housing is introduced into motorized spindle for internal grinding of deep hole.The influence of the housing’s flexible deformation on the rotor dynamics of the motorized spindle should be considered.However,the housing is simplified as a rigid body in the previous modelling for the motorized spindle,this assumption can not meet the requirement of dynamic analysis for such a complex motorized spindle in the study.The dynamic model of the rotor-bearing-housing system for the motorized spindle is established based on the whole transfer matrix method(WTMM)and duplex ball bearing analysis theory considering the flexible deformation of the housing.Critical speed and dynamic stiffness of the spindle are calculated using the model.A case study is carried out to reveal the effects of the housing’s flexural rigidity and the bearing type on the dynamic characteristics of the motorized spindle.A motorized spindle with long-cantilever housing is developed,and its dynamic stiffness is detected to verify the dynamic model.The results show that,the proposed model can be used to analyze the dynamic behavior of the motorized spindle for internal grinding of deep hole.The dynamic performance of the motorized spindle is significantly improved by increasing the bending stiffness of the housing.Both the first order critical speed of the motorized spindle and the static stiffness of the spindle end are increased by replacing light series bearings with ultra-light series bearings.

关 键 词：电主轴 转子动力学 整体传递矩阵法 成对轴承 动态特性 

分 类 号：TH113[机械工程—机械设计及理论]