Thermal-structure Analysis And Temperature Redictive Research On High Speed Motorized-Spindle

Equipment manufacturing industry which provides producing technology and equipmentfor national economy and national defence is the most important factor to influence theeconomy development. High speed CNC (computer numerical control) machine tool is thestrategic industry of equipment manufacturing industry and also a major tool of high speedmanufacturing technology. We must ensure the performance of high speed CNC machine toolto implement of high speed machining. The property of high speed spindle is a core ofperformance of high speed CNC machine tool. Howere, The machine tool now uses highspeed spindle which has the built-in motor to cause serious hot. Comparing to springdeformation, thermal deformation is has more influence on machining accuracy of machinetool. Aimnig at motor spindle of major national science and technology of “HorizontalMachining Center”, the paper establishs temperature field based on finite-element method bymeans of numerical method, and observes thermal deformation in the given temperature field,establishes the predictable model of temperature field of motor spindle with BP nervenetwork. The main works are as follows:1. As far as the mechanism issue of thermal characteristic of HSMS (high speedmotorized spindle) is concerned, expound the basic method of heat transfer, such as, heatconduction, heat convection and heat radiation; analyse the main structure of motor spindle ofhigh-speed horizontal machine centres based on the problem of hot deformation of motorspindle. On the basis, analyse the mechanism of heat transfer of motor spindle, factors ofinfluencing temperature, and mechanism of thermal deformation.2. On the question of the calculation issue of thermal characteristic of HSMS, deducecontact radius and contact load between ball and track of ball bearing based on hertzian theory,and deduce contact angle and angular velocity between inner and outer rings by force andmoment based on controlling raceway theory; Deduce heat calculation formula of ball bearingfrom friction theory and deduce heat calculation formula of cylindrical roler bearing based onthe experiment of демидович B. M. Professor; Summarize generatig heat calculation formulaof motor by power conversion based on the relationship between the input power and theoutput power. On the basis of heat transfer mechanisms of motor spindle, deduce convectiveheat transfer parametric calculation formula of components from nusselt criterion; deduceradiant heat transfer parametric calculation formula of rotor and stator by radiant heat transferprinciple in gray body.3. Besides, another question is the analysing issue of thermal structure of HSMS,simplify and built the motor spindle unit by using the ANSYS software, and analyse the temperature gradient and the thermal deformation under binding boundary conditions throughthe methods of thermo-structural coupled, and make the comparison and analysis of thefactors affecting thermal deformation, and propose measures to improve thermal deformationand methods to improve thermal compensation.4. Finally, when it comes to the temperature predictive issue of HSMS, based on theassembly experimental data of motor spindle, a temperature-forecasting model of motorspindle is established by using BP neural network. The absolute value of accumulative errorshowed that the model which has low error, high precision and high reliability, can be appliedto measure temperature distribution of inter-components while the motor spindle is in motion.