Composite Rail Structure And Dynamic Behavior Rolling And Sliding

Guide is a core part of heavy CNC machine tools, and its mechanical properties affect precision and retentivity of machine tools. However, the traditional sliding rails or rolling guides may not meet the requirements of heavy machine under the condition of high load and cutting load performance. Rolling&Sliding composite rail is a new kind guide of machine tools with the advantages of sliding rails and rolling guides, so it makes heavy machine tools get a good carrying capacity and dynamic characteristics.Firstly, according to the functional requirements, a Rolling&Sliding composite rail with slider was designed and manufactured. Static simulation was carried out in ANSYS and the load distribution relations of rolling joints and sliding joints were got. Then an equivalent mechanics model of Rolling&Sliding composite rail joint was established.Secondly, the vibration displacement of basic component was taken into account and equivalent2-DOF vibration measurement system and the method of dynamic characteristic parameter identification were established to measure the normal and lateral dynamic parameters of the composite rail under complex loading conditions.Thirdly, the variation for dynamic characteristics of Rolling&Sliding composite rail was got form the analysis of test data with different normal load and preload force. The result shows that the increase of normal load can effectively improve the normal and lateral dynamic stiffness and damping of composite rail joints, while the lateral dynamic characteristics can be more susceptible by preload.Finally, a method for joints dynamic modeling with virtual material layer element was proposed based on the numerical relationship of virtual material layer parameters and planar joint dynamic characteristics parameters. This method was applied for the finite element dynamic model of the test device and analysis for the comparison between results of modal simulation and the test results to verify the accuracy of test data. It has also shown this simple method with high reliability can be prior used to establish the dynamic model of whole machine tool.