轴向力下圆锥结合面切向刚度分形模型分析  

Fractal Model of Tangential Stiffness of Conical Joint under Axial Force

作　　者：靳岚[1] 李卫兵 卢世奇 曾鑫磊 JIN Lan;LI Weibing;LU Shiqi;ZENG Xinlei(School of Mechanical and Electrical Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学机电工程学院,兰州730050

出　　处：《组合机床与自动化加工技术》2023年第12期6-11,共6页Modular Machine Tool & Automatic Manufacturing Technique

基　　金：国家自然基金项目(51965035)。

摘　　要：圆锥连接广泛应用于旋转类机械装备,其结合面切向刚度的强弱影响着工况下旋转类设备的回转精度,因此研究圆锥结合面切向接触刚度对提高零件的加工精度有重要的意义。分析其结合面分形维数、特征尺度等参数对切向刚度的影响规律,以表征实际工况的圆锥结合面接触刚度为目的,在构造的圆锥结合面分形模型接触系数的基础上,考虑粗糙面微凸体相互作用的影响,构建了引入域扩展因子的圆锥结合面切向刚度分形模型。以高速主轴-刀柄圆锥连接为应用案例,验证了模型的准确性,并分析了轴向力持续作用下的各相关参数对切向刚度的影响规律。研究结果表明:圆锥结合面分形维数、材料特性系数与切向刚度存在非线性增长关系,且轴向力越大时,这种非线性增长现象愈加明显;在轴向力一定时,随着圆锥结合面的特征尺度参数、切向载荷与法向载荷比值的增加,切向刚度呈减少趋势。The tapered joint is widely used in rotating machinery and equipment,and the strength of the tangential stiffness of its bond surface affects the rotary accuracy of rotating equipment under working conditions.Therefore,it is important to study the tangential contact stiffness of conical joints to improve the machining accuracy of the parts,and to analyze the influence of fractal dimension and characteristic scale of the joints on the tangential stiffness.In order to characterize the contact stiffness of the conical bond surface under actual working conditions,a fractal model of the tangential stiffness of the conical bond surface is constructed based on the contact coefficients of the constructed fractal model of the conical bond surface,taking into account the influence of the interaction of the micro-convex bodies on the rough surface,and introducing the domain expansion factor.The accuracy of the model is verified by taking the high-speed spindle-shank conical joint as an application case,and the influence law of each relevant parameter on the tangential stiffness under the continuous action of axial force is analyzed.The results show that there is a nonlinear growth relationship between the fractal dimension of the conical joint surface,the material property coefficient and the tangential stiffness,and the larger the axial force,the more obvious this nonlinear growth phenomenon;at a certain axial force,the tangential stiffness tends to decrease with the increase of the characteristic scale parameter of the conical joint surface,the ratio of tangential load to normal load.

关 键 词：圆锥结合面 切向刚度 分形模型 微凸体相互作用 域扩展因子 

分 类 号：TH161[机械工程—机械制造及自动化] TG502[金属学及工艺—金属切削加工及机床]