Milling Spindle System Rigid-flexible Coupling The Multibody Dynamics Modeling And Simulation Analysis

Nowadays the mainstream of research and manufacture of machine tools is mechanical system which has high speed, effect, rate of load and mass, precise and complex properties. From the desire of modern productivity, precision and reliability, High or simi-high Speed Machining requires mechanical systems with high dynamic properties. However, the machining capability of mechanical systems almost depends on the dynamic response properties and reliability of Spindle systems in many engineerings.Based on the co-project of "Establishing Technique Center of Kunming Mill Machine Factory", accomplished by Yunnan Province and Kunming University of Science and Technology, the Spindle system dynamic model was analyzed according to Finite Element Method, Multi-bodies Flexible System Dynamics and the modified modal integral coupling method of Craig-Bampton. A numerical method on forecasting the dynamic response of multi-bodies flexible spindle system effectively was given by this dissertation. The new method can effectively deal with the dynamic response of spindle system with multi-dynamic parameters excitation and the simulation results provide basic data for Spindle system dynamic design and valuable theoretical basis for further research on dynamic response of Spindle system.The numerical analysis and its application were comprehensively and systematically studied. It's about co-design and simulation of Spindle system of milling machine, modeling the rigid and flexible coupling Spindle system, dynamic contact analysis of angular contact ball bearing, analysis on the inherent characteristics and dynamic response of spindle and bearing coupling model, dynamic analysis on multi-bodies flexible Spindle system.The contact dynamic model and numerical method of angular contact ball bearing was proposed on the basis of the theory of Hertz Contact Dynamic with the effect of speed, axis and radial preload, friction and centrifugal force. The coupled dynamic model of spindle and bearing was proposed on the basis of the modified modal integral coupling method of Craig-Bampton. Accomplish analysis on the inherent characteristics and dynamic response and validate the correctness of the analysis model and results with the data of EAM in the literature [91]. As a whole, the dynamic response of multi-bodies flexible Spindle system takes on periodicity and stability, the results indicate that it has preferable dynamic properties.From the results, we know the speed frequency is safe from triggering off the resonance of Spindle system, but the frequency of cutting force with six tooth-end milling cutter is out of the safe frequency range of Spindle system. Under two special conditions about the power experiment of the vertical Spindle, the cutting depth are 2/3 of max and max, the max displacements of radial vibration of the flexible spindle are both at the milling cutter, NODE ONE. The displacements is relatively big and having strong circles. It supports the Spindle has goog properities. Under the speed 4000rpm, the max displacement of radial vibration of the flexible spindle is at the milling cutter, NODE ONE. It's more than that of flexible spindle and bearing model. However, the velocity and acceleration of the Spindle vibration are much bigger and support this miling machine may not be suitable for working at the speed 4000rpm using six teeth cutting.