滚珠直线导轨副分形磨损模型及精度退化研究

Studies of linear ball guideways' fractal wearmodel and accuracy degradation

为研究滚珠直线导轨副磨损和精度损失规律,基于赫兹接触理论建立了滚珠直线导轨副力学模型。使用分形函数表征滚珠和滑块滚道接触区表面,并采用结构函数法求得滚道表面的分形参数。考虑滚珠和滑块滚道之间的润滑状态,在分形接触模型下对滚珠和滑块滚道接触区域的微分形表面进行了受力分析。基于粘着磨损理论分析了滚珠和滚道接触面微凸体的磨损过程,并在此基础上结合蠕滑理论建立了滚珠和滚道接触面的分形磨损模型。最后,以某型号滚珠直线导轨副为研究对象进行了仿真分析,得到不同载荷和不同跑合距离下滚珠直线导轨副磨损和精度退化规律。

Based on the Hertz contact theory,a mechanical model of linear ball guideways was built to study the wear rule and accuracy degradation of linear ball guideways. The contact area between the ball and the slider＇s raceway was characterized by the fractal function,and the raceway＇s fractal parameters were obtained by using the structure function analysis method. Under the considering of the lubrication state between the ball and the slider＇s raceway,the asperities load capacity was obtained by using the fractal contact model. The wear between the ball and slider＇s raceway was analyzed through the adhesive wear theory,and then,the fractal wear model of linear ball guideways was established with the creep theory. Finally,the simulation analysis for a certain type of the linearball guideway was conducted,and the wear rules and accuracy degradation of the linearball guideway under different loads and running distance were obtained by the calculation simulation.