Analysis On The Thermal Characteristics And Thermal-Structure Coupling Of Aerostatic Motorized Spindle

Ultra-high-speed aerostatic piezoelectric main shaft is one of the main bodies for realizing high-speed and high-speed cutting.It is characterized by air-floating support and electromagnetic direct drive as the typical structure,and its comprehensive performance is subject to electrical,magnetic,gas,solid,thermal,and other physical physics.The influence of the field.This paper analyzes and analyzes the thermal effects of the spindle during the rotation process,resulting in spindle heating and structural deformation.The main objective of the analysis is to improve the thermal performance of the air-piezoelectric spindle machine tool,improve its overall performance,and to solve The thermal characteristics of ultra-high-speed aerostatic piezoelectric spindles provide theoretical support and computational support.The aerostatic piezoelectric main shaft incorporates the air hydrostatic bearing technology and electric spindle technology,with zero gap transmission,high speed,high precision,low friction,low vibration and so on,so it has broad application prospects,is a domestic and foreign scholars contending to study One of the hot issues.At present,the domestic scholars mainly study the dynamic and static problems of the aerostatic piezoelectric main shaft,and there are few thermal analysis and thermal-structure coupling analysis.In this paper,an aerostatic piezoelectric main shaft manufactured by a company is taken as the research object,and the thermal characteristics and thermal-structure coupling of this type of aerostatic piezoelectric main shaft are analyzed and studied.The main tasks are:Firstly,The heat transfer method and heat transfer coefficient between the aerostatic piezoelectric spindle heat source and the electric spindle system structure were analyzed and calculated;and the heat generation rate,the average film thickness,the spindle rotation speed,and the air of the aerostatic bearing were obtained respectively.The relationship between the dynamic viscosity and the influence of the convection heat transfer coefficient of the electric spindle,the rotation speed of the spindle,the air flow rate of the air system,and the film thickness.Secondly,The finite element model of the aerostatic piezoelectric main shaft is established,and the temperature field distribution of the main components of the aerostatic piezoelectric main shaft under steady state is obtained.The temperature changes of main components of the aerostatic piezoelectric main shaft under different working conditions are analyzed and passed.Cross-test optimization optimizes the primary and secondary factors that affect the thermal characteristics of the aeroelastic piezoelectric spindle and the best combination of boundary conditions.Then,The workbench software was used to analyze and calculate the pressure distribution in the air film area.The effect of the average air film thickness on the static stiffness of the bearing was obtained.By establishing the thermal-structure coupling analysis model of the main shaft,the thermal deformation of the main shaft was obtained.And the relationship between the thermal deformation of the spindle and the spindle speed,and analyzed the influence of the thermal deformation of the spindle on the static stiffness of the bearing.Finally,The temperature test experiment was conducted on the aerostatic piezoelectric spindle under no-load stable operation.The experimental data obtained were basically consistent with the simulation data.This shows that the processing method of the finite element analysis model is reasonable,and the calculation results and settings of the boundary conditions are correct.The results have a certain reference value.