Research On Rotor Unbalance Identification And Active Balancing Of High-speed Precision Motorized Spindle

With the "Made in China 2025" proposal,the intelligent manufacturing has become a current research hotspot.The CNC machine tools are industrial master machines used in equipment manufacturing.High-speed precision motorized spindle is the core component of high-end CNC machine tools.However,during the manufacture,assembly and operation of spindle,due to factors such as uneven materials,processing and assembly errors and tool wear or breakage,it will inevitably cause the problem of mass unbalance.The high speed of motorized spindle,even a small amount of unbalance,will cause a large centrifugal force,which will cause the system to vibrate violently.Therefore,the real-time diagnosis and control of unbalance-induced vibration of motorized spindle is of great significance for the development of high-speed and high-precision machine tools.In this paper,the in-depth study of the motorized spindle rotor unbalance fault is carried out.From the aspects of fault identification and online active balancing,the diagnosis and treatment of the motorized spindle unbalance fault is systematically studied,and the software and hardware systems are designed and developed to provide a reliable guarantee for the safe operation of the motorized spindle.Firstly,for the motor,rotor and bearing of motorized spindle,as well as the cooling,lubrication and balancing devices,the key parameter design and component selection were completed.Based on this,the motorized spindle system platform with functions such as multi-information monitoring and analysis,automatic alarm and speed reduction processing was completed,and modal test experiments were carried out on the developed spindle system platform,which provides a basis for unbalance identification and active balancing.Secondly,the vibration signal analysis methods including FFT and vibration image analysis methods of grayscale texture analysis,symmetrical polar image texture analysis,and EMD-PWVD time-frequency energy interval division were studied to completed the extraction of spindle rotor unbalance fault feature.Combined with the FCM clustering algorithm,the spindle rotor unbalance fault identification is realized,and the spindle system platform was tested to verify the effectiveness of the proposed method.Then,based on the balance principle,a double-weighted polar coordinate type mechanical active balancing device was designed from the three aspects of overall structure,transmission mode and balance ability,and its actuation control simulation was completed on the basis of the establishment of the control model;According to the characteristics of the device,the balance method of influence coefficient was proposed,and the development of the online active balance system was completed.The overall system platform was used to test and verify the balance performance of the system.Finally,on the basis of platform development and method research,using Lab View and MatLab joint programming,the integrated software integration of the diagnosis and treatment of the motorized spindle rotor unbalance fault was realized,the software system was functionally verified,and the motorized spindle was completed using the entire set of software and hardware systems.Fault diagnosis and cure application of rotor unbalance proves the practicality of the system.