The Dynamic Analysis And Experiment Of High-Performance NC Machine Tool Spindle-Part

High-speed and high-accuracy are the trends in development of machine tool, The spindle-part is the complication part of the tool machine. its dynamic characteristic is a important influence for the function of the tool machine.With the subsidizes of the important projects which are tackled key problem by Chongqing Science(CSTC,2005AC3029) and Technology Commission and by the science-technology of Chongqing city(CSTC,2006AA3010).For the purpose of advancing rotation speed and improving dynamic characteristic , we cooperate with Chongqing NO.2 Machine Tool Works to do study on dynamic characteristic analyze and application.In the paper, the current situation of the rotation speed of tool machine and the development trends of the dynamic research of the spindle-part are summarized. Basis on this ,the modal experiment and finite element model are taken to use by tied the current developing trend.The basic resolving processes about the modal parameters identifier theory. Then, carried out the line frames of the spindle and the headstock. The modal parameters are obtained by experiment, which used the single-input multi-output method. The spindle static stiffness is tested by using the force sensor and strain gauge.The finite element models of the spindle and the headstock. are carried out .The modal frequency and modal shape characteristics are obtained by FEM modal analysis with the Lanczos method .Compared the dada of the experiment, it is proved that the FEM modals are right.. Improved schemes of headstock is suggested by the result of the modal analysis.The flexibility support of bear of the NC spindle-part is simulated by using the Multi-Point Constraint method to build the finite element model; The static analysis of the spindle-part is carried out by basis on the model, comparing to the result of experiment. The modal frequency and modal shape characteristics are obtained by FEM modal analysis with the Lanczos method. The transient response of spindle-part adopts the modal superposition method with the modal parameter by experiment on. basis of the model. The direction of the structure improvement is pointed out by the displacement response picture which is obtained by the transient response analysis. And the frequency region of the resonance in work is obtained by the spectral analysis. It provides theoretical basis for promoting the precision and rotational speed of the spindle parts.