Development Of High-speed Motorized Spindle Reliability Test Bench Based On Electro Hydraulic Servo System

As one of the essential functional components of CNC lathe，high-speedmotorized spindle’s reliability level makes a big difference on reliability of CNC. Soit has a great significance on enhancing the reliability of CNC and increasing marketshare to research the reliability of high-speed spindle. Reliability research base onfailure data, which can be gotten from reliability tests by building test platform in thelab. Most of the existing spindle test platforms cann’t reflect spindle’s actual stresscondition as they only run the spindle with free load or static load. So a dynamicloading device that can simulating the spindle’s stress condition should be developedto get more realistic data.This paper proposed a reliability test solution base on a dynamic loading deviceconsists of electro hydraulic servo system and electrical dynamometer, and built a testplatform. The maximum static force and torque of the spindle was worked out byforce analysis. The dynamic force was calculated by analysed the frequency domainwaveform figure of cutting force. The spindle was loaded by electrical dynamometerto simulate its torque and drive mechanism was designed. In order to simulatedspindle’s stress, valve regulated electro hydraulic servo system was researched anddeveloped.The mathematical model of system was built and the stability of systemwas analysed by nyquist criterion and Bode diagram. Then the stability of servosystem was optimized by added damping link. Strength of the platform’s mechanicalpart was checked by Ansys. Control system was developed whose software written byVB. Electric signals and drive were controlled by DAQ Card, photoelectric coupler,relays and contactors. Hardware circuit was processed on anti-jamming and feedbacksignal was processed on filtering by UKF algorithm.After debugged and ran for a period of time, it’s showed that the platform canconduct reliability test continuously and stably while the electro hydraulic servo system and electrical dynamometer having a good effect. The success of this platformlay a good foundation of acceleration reliability test and make a big difference on thereliability research of CNC.