摘要
针对目前主轴动态刚度研究中存在的建模过程复杂、计算量大、忽略轴承受力分析的问题,结合理论建模及实验测试,系统研究了定压预紧主轴轴向动态刚度随轴向载荷的变化规律。基于球轴承轴向载荷与轴向变形的经验公式,建立了定压预紧主轴轴向动态刚度分析模型,理论推导出定压预紧主轴轴向动态刚度随轴向载荷的变化关系;设计了定压预紧主轴动态刚度测试实验,实现了对工作状态下主轴轴承位移量及相应轴向载荷的精确测试;求解了主轴的轴向动态刚度,并与仿真数据进行了对比。实验结果表明:在前轴承内外圈压紧方向,随着轴向力的增大,主轴的轴向刚度呈现增大趋势;在前轴承内外圈脱离方向,随着轴向力的增大,其主轴的轴向刚度先减小后趋于定值。实验结果验证了模型仿真的有效性和正确性。
Dynamic stiffness of a spindle in condition of service state changes with the operating conditions and loads, and is the main indicator of the dynamic performance of the spindle. The deficiency of the current study is that the model is very complex with large amount of calculation, and the load characteristic of bearing is always ignored during analysis. The relationship between axial load and stiffness of fixed-pressure spindles is systematically researched through the combination of theoretical methods and experimental tests. A model of fixed-pressure preload spindle is built based on the empirical formula of relationship between axial load and axial deformation, and the dynamic relationship between axial dynamic stiffness of spindle and axial load is theoretically derived. Then an experiment to test the dynamic stiffness is designed. Axial force is applied to the working spindle and its displacement is tested using three displacement sensors. The stiffness of the spindle is calculated and compared with simulation data. Experimental results show that the dynamic stiffness of the fixed-pressure preload spindle increases with the increase of axial load when the outer ring and inner ring of the front bearing of the spindle are compressed, and the stiffness reduces first and then tends to be constant with the increase of axial load when the outer ring and inner ring of the front bearing of the spindle separate.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2014年第10期126-130,共5页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金资助项目(51275383)
国家重点基础研究发展规划资助项目(2011CB706606)
关键词
定压预紧
主轴轴向刚度
轴向载荷
轴向变形
fixed-pressure preload
axial stiffness of spindle
axial load
axial deformation
