Research And Analysis Of Noise Of High Speed Motorized Spindle

With the "Made in China 2025" manufacturing power strategy proposed by China,the"high-end CNC machine tool research" as a key industry will vigorously promote the development of CNC machine tools towards the direction of high speed and precision.However,as the core component of high-grade CNC machine tools,the motorized spindle unit has a serious impact on the service life,processing accuracy and the surrounding environment of the machine tool due to its noise problems.Therefore,with the support of the National Natural Science Foundation of China(51675353),the noise of high-speed motorized spindle was analyzed,which provides a theoretical basis for the future motorized spindle noise reduction and achieve low noise optimization design.In this thesis,the noise source of spindle and its noise in high-speed operation were analyzed by finite element analysis and experimental methods.The specific work contents are as follows:(1)Starting from the basic structure and working principle of motorized spindle,the types of motorized spindle noise were preliminarily expounded,and the causes and influencing factors of the motorized spindle noise and the main sources of noise were theoretically analyzed.(2)An experimental platform for the noise source of the motorized spindle was built.After data processing and spectrum analysis of noise signals collected by sound pressure sensors parallel to different locations on the plane of the spindle,the main sound source location of motorized spindle was found out,the frequency components and the type of noise in the mixed were identified.(3)An experimental platform for the noise characteristics of the motorized spindle was set up.Through the experimental study on the noise characteristics of the 150MD24Y30 motorized spindle and the 100MD60Y4 motorized spindle at steady speed,the correlation between the noise of the spindle and its rotational speed was obtained.The difference of the noise for the two motorized spindle was obtained.The effect of the size of caring inner ring on the spindle noise was analyzed.The noise signal of the 100MD60Y4 motorized spindle during the braking phase is compared with the noise signal during stable operation,which verifies the noise characteristics of the motorized spindle during the braking phase.(4)Electromagnetic field of motorized spindle was analyze by finite element method.The two-dimensional finite element model of the motorized spindle was established by Ansys Maxwell modular and the electromagnetic field distribution of the motorized spindle was imvestigated when different shaft materials are used.At the same time,the air gap magnetic density and radial electromagnetic force of different slot matching and eccentricity conditions of the motorized spindle were studied respectively,the influence of the structural parameters of the motorized spindle on its noise was analyzed,and compared with the theoretical results.(5)Based on the comprasion on analysis between the simulation calculation of the noise characteristics of the high-speed motorized spindle and the experimental results,several specific measures for noise reduction and noise reduction were proposed.