Analysis Of Key Indicators In The Design Of High-speed Motorized Spindles And Research On The Influence Of Characteristics

With the rapid development of manufacturing technology,high-speed and highprecision CNC machine tools have gradually become the core equipment in the field of mechanical manufacturing.As the core functional component of CNC machine tools,the performance of the high-speed electric spindle will directly affect the stability and reliability of the part processing.In order to further improve the performance of CNC machine tools,it is particularly important to analyze the key indicators and the influence of their characteristics in the design process of the electric spindle.Therefore,this article takes the high-speed electric spindle as the research object,and conducts the following research:The structural characteristics of the high-speed electric spindle are analyzed,and the key indicators that affect the performance of the electric spindle are obtained,including support characteristics,fit relationships,and static-dynamic characteristics.Based on the Hertz contact theory,the force model of angular contact ball bearings under the action of axial preload is established,and the relationship between the axial preload and bearing contact angle,contact load and contact displacement is obtained.At the same time,the relationship between the preload force and the temperature rise,life and stiffness of the bearing,as well as the relative positional relationship and force between the inner rolling element and the inner and outer rings of the bearing when the bearing rotates at high speed are analyzed.Based on elastic mechanics,the fit relationship between the inner ring of the angular contact ball bearing and the spindle,the outer ring of the bearing and the bearing seat is analyzed,and the contact stress and radial displacement of the bearing at the fit surface are obtained,and the influence of the fit tolerance on the contact angle and stiffness of the bearing is revealed;the fit relationship between the motor rotor and the spindle is analyzed,and the fit interference and stress distribution of the electric spindle at different speeds are obtained;the machining error,assembly error and thermal error are carried out analyze and explore the influence of different working conditions on the fit relationships of the high-speed electric spindle.Based on material mechanics and rotor dynamics,the static-dynamic characteristics of the high-speed electric spindle and its influencing factors are analyzed,and the relationship between the static stiffness of the spindle and the bearing preload,the spindle span and the overhang are obtained.The modal and harmonious response of the electric spindle are simulated by finite element method,and the dynamic performance of the electric spindle is discussed under different preload,spindle span and overhang.