预紧力对滚柱直线导轨副刚度特性影响的研究

Study on influence of preload on the stiffness characteristics of rollers linear guides

滚柱直线导轨副是数控机床的重要功能部件,研究预紧力对其刚度特性的影响,是对机床进行准确动态优化设计和振动控制的重要基础。文章建立了导轨副的刚度模型,利用ANSYS Workbench仿真了不同预紧力下的滚柱直线导轨副,得到了其在不同预紧力下弹性变形量和各阶固有频率,分析了预紧力对滚柱直线导轨副刚度特性的影响规律,并通过不同预紧力对导轨静刚度的影响进行实验分析和模态分析,验证了仿真方案。结果表明:对滚柱直线导轨副合理施加预紧力,可以显著地提高滚柱直线导轨副的静刚度,增加滚柱直线导轨副的承载能力;滚柱直线导轨副的预紧力增大时,各阶固有频率相应增大,而持续增大预紧力时,滚柱直线导轨副的固有频率变化明显变小。

Roller linear guide pair is an important functional part of computerized numerical control machine tools.Studying the influence on stiffness characteristics is an important basis for accurate accurate dynamic optimization design and vibration control.The paper establishes the stiffness model of the guide rail pair by using ANSYS Workbench simulation software under different preloading forces.It analyzes the linear guide rail pair of the roller is simulated,obtains the elastic deformation amount and the natural frequency of each linear preload of the roller linear guide,analyzes the influence of the preload on the stiffness characteristics of the linear guide of the roller.The results show that the natural frequency of each step increases correspondingly when the pre-tightening force of the ball linear guide pair increases and the reasonable pre-tightening force can significantly improve the static stiffness of the roller linear guide pair and improve the bearing capacity of the roller linear guide pair.