Analysis Of Characteristics Of Motorized Spindle System Based On Thermo-mechanical Coupling Model

As a pillar industry of the national economy,the mechanical processing manufacturing industry has made great progress while the rapid development of China's economy.High-speed processing technology has become more and more concerned because of its high efficiency,high quality and low consumption.As one of the core components of high-speed computer number control(CNC)machining tools,the motorized spindle system determines the machining quality and precision of the machine tool to a large extent.Therefore,it is very important to analyze the dynamic and thermal characteristics of the motorized spindle system.In this paper,ES series BT40-4011-1500/12000-CX motorized spindle system of a company is taken as the research object.Based on the rotor dynamics and heat transfer theory,the finite element method is used to establish the thermo-mechanical coupling model of the motorized spindle system.The effects of dynamic and thermal characteristics in the system are fully considered,and the coupling characteristics during system operation are effectively predicted.The main contents include:(1)Briefly describe the basic components of the motorized spindle system.The basic structure of this type of motorized spindle system is briefly introduced.The main components and related parameters are introduced.In particular,the lubrication system and cooling system of the electric spindle system are mainly introduced,which lays the foundation for the subsequent analysis of system characteristics.(2)Dynamic characteristics analysis of the motorized spindle system.According to the relevant size parameters of the motorized spindle system,the two-dimensional and three-dimensional models of the system are established by using the drawing software,and the system is divided into units.The system dynamics model is established by the finite element method,and the main factors affecting the natural frequency of the system are analyzed.And the vibration response of the tool nose under different working conditions are analyzed in detail.(3)Thermal characteristics analysis of the motorized spindle system.Based on the theory of heat transfer,the main heat source,the heat transfer and heat dissipation mechanism of the motorized spindle system are analyzed and calculated.In addition,the thermal resistance network model of the system is established based on Kirchhoff s law and energy conservation principle to obtain the state and transient temperature field distribution of the system.And the influence of relevant factors on the temperature variation of the system are analyzed.Furthermore,based on this model,the thermal displacement of the front and rear bearings is calculated,and its influence on the natural frequency of the system is analyzed.(4)Thermo-mechanical coupling characteristics analysis of the motorized spindle system.By combining the governing equations of the dynamic model and the thermal model of the motorized spindle system,and considering the interaction between dynamic and thermal characteristics,a thermo-mechanical coupling model of the motorized spindle system is established based on the finite element analysis method.The dynamic response and thermal characteristics of the system under different working conditions are analyzed based on this coupling model in detail.At the same time,the temperature rise experiment of the motorized spindle system is designed and carried out.And the rationality of the model is verified by the comparison of experiment and simulation results.In summary,the thermo-mechanical coupling model of the motorized spindle system is established by the finite element analysis method,which fully considers the interaction between the dynamic characteristics and the of the temperature variation of the motorized spindle system.The dynamic characteristics and the thermal characteristics of the system in the actual working process and can be effectively predicted based on this model.It can provide a basis for further optimization design and research of the motorized spindle of CNC machine tools,which has certain academic significance and economic value.