多参量耦合的电主轴热特性建模及分析
Modeling and Analyzing Multi？？Variable Coupling Thermal Characteristics for Motorized Spindle

为了深入研究电主轴热特性,通过分析轴承非线性力学特性与热效应间的耦合作用机制,建立了综合考虑热诱导预紧力和黏温效应的轴承动态生热计算模型;在引入接触热阻的基础上,基于系统内部多参量耦合关系,建立了电主轴热？步峁柜詈霞扑惴椒āＲ阅承秃诺缰髦嵛？试验平台,进行了温升及热变形试验,利用试验数据对所建模型和分析方法进行了验证。最后,采用所建模型,对电主轴进行了热特性分析,结果表明:不同工况下电主轴仿真结果与试验数据吻合度良好,所建模型和分析方法进一步提高了仿真计算精度;电主轴温度场分布表现为外冷内热;轴芯热积聚导致的电主轴轴向热伸长是影响加工精度的主要因素;受到配合方式和装配位置的影响,轴承在温升过程中预紧力不断减小。
Considering the coupling behaviors between the non？？linear mechanics character and the thermal effect, a dynamic heat calculation model for rolling bearings taking heat？？induced preload and temperature？？viscosity effect into account is established. A thermo？？structural coupling calculation method introducing the thermal contact resistance is developed according to the coupling parameters in the motorized spindle system. The temperature rising and thermal deformation tests are carried out to verify the accuracy of this model and algorithm, and the thermal characteristics of the motorized spindle are analyzed. It is found that the simulation results coincide well with the experimental data under different working conditions to indicate the effect of the proposed model on improving simulation precision. The temperature field distribution of the spindle trends high inside and low outside. The thermal expansion of spindle caused by the heat accumulation of shaft mainly affects the manufacturing accuracy. During the temperature rising process, the preload of bearings decreases due to the fitting manner and the assembly position