Dynamic Analysis And Experimental Study On Coupling Fault Of Rotor-Rolling Bearing Of Motorized Spindle

As one of the core component of CNC machine tools,high-speed motorized spindle is the carrier of advanced manufacturing technology,and its various performances will directly affect the development of CNC machine tools and even the entire manufacturing industry.In order to ensure the normal operation of the motorized spindle under actual working conditions and the processing quality of the processed product,the dynamic characteristics during the operation of motorized spindle have received extensive attention.In this thesis,the high-speed motorized spindle rotor-rolling bearing system is taken as the research object.The dynamics of the motorized spindle and the spindle fault mechanism are taken as the research basis,the dynamic of the motorized spindle rotor-rolling bearing system was investigated in the case of misalignment,unbalanced and rubbig single and coupling failure.Firstly,the basic structure,principle and failure mechanism of the motorized spindle are clarified,and the positions,types and formats for frequent faults are also analyzed.The AIC9916FS equipment fault simulation diagnosis and analysis system are introduced,which lays a foundation for establishing the simulation model and realizing the spindle fault dynamics analysis.Secondly,the finite element method and the Riccati transfer matrix method are used to analyze the dynamics and vibration response of the motorized spindle system.According to the existing experimental conditions,the dynamic singles of the motorized spindle under actual operating conditions are collected.The simulation results are compared with the experimental results,and the dynamic characteristics are obtained.The correctness of the model is verified and the basis for the subsequent dynamics behavior analysis of the motorized spindle is obtained.Then,based on the above work,the dynamic characteristics under misalignment,unbalance and rubbing fault conditions for the high-speed motorized spindle rotor-rolling bearing system are studied.In order to carry out the above work,the single and coupling dynamics modes of the rotor-rolling bearing system of motorized spindle are established.Based on the faulty rotor test bench,the actual operation of the rotor under single and coupled fault conditions is simulated by setting the misalignment,unbalance and rubbing clearance.By comparing and analyzing the simulation data and experimental data,the dynamic characteristics of the motorized spindle under single and coupled faults are obtained,and the correctness of the coupled fault simulation model is verified.Finally,according to the mechanism of the failure of the rotor-rolling bearing of the motorized spindle and the dynamic characteristics under the fault condition,multiple uncertain factors are considered such as the manufacture of the rotor of the motorized spindle,the running wear and the installation error,etc..Both Monte Carlo and the response surface method are used to analyze the reliability of the motorized spindle.