scholarly journals Study on the Unbalanced Fault Dynamic Characteristics of Eccentric Motorized Spindle considering the Effect of Magnetic Pull

2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Zhan Wang ◽  
Wenzhi He ◽  
Siyuan Du ◽  
Zhe Yuan

Unbalanced fault is the most common fault of high-speed motorized spindle, which is the main factor affecting the machining accuracy of high-speed spindle. Due to the unbalanced magnetic pull produced by the air gap eccentricity of the stator and rotor, the unbalanced vibration of the motorized spindle will be further aggravated. In order to explore the dynamic behavior and motion law of the unbalanced fault motorized spindle under the eccentric state, a dynamic model of the unbalanced fault of the high-speed motorized spindle considering the unbalanced magnetic pull was established. Taking the eccentric motorized spindle customized by the research group as the research object, the dynamic model is established, simulated, and analyzed, and the response change law of motorized spindle under the effect of different speed, unbalance, and air gap is obtained. The simulation results show that the unbalanced magnetic pull caused by static eccentricity will increase the unbalanced vibration of motorized spindle, and the unbalanced vibration will also increase with the increase of static eccentricity. The vibration caused by unbalanced magnetic pull does not increase with the increase of rotating speed. In frequency-domain analysis, when there is unbalanced magnetic pull, the peak appears at 0 Hz, and the amplitude of fundamental frequency vibration will increase with the increase of eccentricity. The experimental results show that the greater the eccentricity is, the greater the unbalance vibration of the motorized spindle is. The experimental results are consistent with the simulation results, which further verify the accuracy of the model. The research results lay a theoretical basis for fault analysis and diagnosis of coupling fault motorized spindle.

2011 ◽  
Vol 228-229 ◽  
pp. 66-71
Author(s):  
Xiao Hong Lu ◽  
Zhen Yuan Jia ◽  
Zhi Cong Zhang ◽  
Xv Jia

The fixture of motorized spindle significantly affect the vibration of micro high speed CNC milling machine, its performance can directly affect the machining accuracy of the entire micro milling machine. A special fixture of high-speed motorized spindle is designed in the paper and its static characteristics are checked by utilizing ANSYS finite element analysis software. To guarantee the sufficient strength of bolts and the safety of motorized spindle when the motorized spindle runs at high speed, theory analysis method and ANSYS finite element analysis method are used to make the strength check of the fixture. The designed special fixture for high speed motorized spindle plays an important part in the design of high-speed motorized spindle.


2018 ◽  
Vol 2018 ◽  
pp. 1-13
Author(s):  
Weidong Lv ◽  
Guoqiang Wang ◽  
He Tian

This paper presents a dynamic simulator of the electromechanical coupling start-up of a ball mill. The electromechanical coupling model based on the dynamic model of the ball mill, the characteristic equation of the clutch, and the dynamic model of the induction motor is established. Comparison between the simulation results of angular speed, load torque and current obtained from the model, and the experimental results is conducted to validate the correctness of these simulation results. Results show that the simulation results of the electromechanical model are highly consistent with the experimental results. Two indexes are proposed for evaluation. Finally, a 4500 kW ball mill is used to analyse the start-up process with different operation parameters of the air clutch. The effect of the engagement time and the pressure of the air clutch on the torque, current, and shock extent is analysed. Moreover, the optimum inflation time is determined.


2013 ◽  
Vol 321-324 ◽  
pp. 739-742
Author(s):  
Yu Huang Zheng

Vacuum circuit breaker becomes more and more complicated, integrated, high-speed and intellectualized. To insure vacuum circuit breaker in its good conditions, the function of fault diagnosis gets more important than before in the process of repairing. This paper is addressed a model-based fault detection methodology for vacuum circuit breaker. At first, the dynamic model of vacuum circuit breaker is built. Secondly, DTW algorithm is introduced to compute the similarity value between the test data and the theoretical data. At last, the value comparison between the similarity and the threshold concludes whether a fault has occurred or the vacuum circuit breaker has potential hazardous effects. The experimental results show that this method is effective.


2011 ◽  
Vol 335-336 ◽  
pp. 547-551 ◽  
Author(s):  
Li Xiu Zhang ◽  
Yu Hou Wu ◽  
Li Yan Wang

Engineering ceramic is the ideal material for high-speed and high precision motorized spindle due to perfect characteristics of light weight, wear resistance, high temperature, high strength, and so on. The air-gap is changed due to the influence from various factors not only the tolerance of the manufacture and assembly of motorized spindle but also different working condition. The change of air-gap impacts on vibration performance of motorized spindle. The effects of rotating speed and air-gap between the rotator and stator on these characteristic parameters of the motorized spindle are analyzed. This paper analyses the effect change of air-gap on vibration performance of motorized spindle by the simulation analysis and experimental. The results show that vibration increase with the decrease of air-gap. Meanwhile, electromagnetic vibration increase with the increase of eccentricity of motorized spindle. These results are very helpful to the structure optimization and application of the ceramic motorized spindle.


2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Xiaopeng Wang ◽  
Yuzhu Guo ◽  
Tianning Chen

High speed motorized spindle has become a key functional unit of high speed machine tools and effectively promotes the development of machine tool technology. The development of higher speed and more power puts forward the stricter requirement for the performance of motorized spindle, especially the dynamic performance which affects the machining accuracy, reliability, and production efficiency. To overcome the problems of ineffective loading and dynamic performance measurement of motorized spindle, a noncontact electromagnetic loading device is developed. The cutting load can be simulated by using electromagnetic force. A new method of measuring force by force sensors is presented, and the steady and transient loading force could be measured exactly. After the high speed machine spindle is tested, the frequency response curves of the spindle relative to machine table are collected at 0~12000 rpm; then the relationships between stiffness and speeds as well as between damping ratio and speeds are obtained. The result shows that not only the static and dynamic stiffness but also the damping ratio declined with the increase of speed.


Machines ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 286
Author(s):  
Zhaolong Li ◽  
Bo Zhu ◽  
Ye Dai ◽  
Wenming Zhu ◽  
Qinghai Wang ◽  
...  

High-speed motorized spindle heating will produce thermal error, which is an important factor affecting the machining accuracy of machine tools. The thermal error model of high-speed motorized spindles can compensate for thermal error and improve machining accuracy effectively. In order to confirm the high precision thermal error model, Beetle antennae search algorithm (BAS) is proposed to optimize the thermal error prediction model of motorized spindle based on BP neural network. Through the thermal characteristic experiment, the A02 motorized spindle is used as the research object to obtain the temperature and axial thermal drift data of the motorized spindle at different speeds. Using fuzzy clustering and grey relational analysis to screen temperature-sensitive points. Beetle antennae search algorithm (BAS) is used to optimize the weights and thresholds of the BP neural network. Finally, the BAS-BP thermal error prediction model is established. Compared with BP and GA-BP models, the results show that BAS-BP has higher prediction accuracy than BP and GA-BP models at different speeds. Therefore, the BAS-BP model is suitable for prediction and compensation of spindle thermal error.


2018 ◽  
Vol 29 (13) ◽  
pp. 2754-2765 ◽  
Author(s):  
Shengli Tian ◽  
Xiaoan Chen ◽  
Ye He ◽  
Tianchi Chen ◽  
Peiming Li

A high-speed dynamic loading test is a key step when testing the dynamic performance and running quality of a high-speed motorized spindle. A loading test is very difficult to perform at high speeds. Based on the rheological behavior of the magnetorheological fluid, a novel high-speed dynamic loading system for a high-speed motorized spindle was designed, fabricated, and tested. The working principles and structure of this loading system are described. The torque model of the loader was derived based on the Herschel–Bulkley model and electromagnetic simulation using the finite element method. In addition, the torque–current relationship under different speeds was analyzed by experiments, and we found non-linear relationships between the viscosity and shear stress of the magnetorheological fluid with the shear rate. The Herschel–Bulkley model was corrected by fitting for the experimental results. The loading torque, calculated by the modified model, complied with the experimental results. This lays the foundation for the design of a high-speed transmission device based on the magnetorheological shear principle. Experiments of torque stability, temperature stability, and reusability verified the feasibility and accuracy of the proposed loading system. It provides a novel method to test the dynamic loading performance of high-speed motorized spindles.


2014 ◽  
Vol 623 ◽  
pp. 85-89
Author(s):  
Yu An He ◽  
Yan Ming He

High-speed motorized spindle of NC machine tools is the core component for high speed machining. Production efficiency, machining accuracy, processing quality are greatly improved, and production cost is reduced by high speed machining. The paper describes the common failure modes of high-speed motorized spindle. By the fault tree analysis method, failure modes of motorized spindle are modeled, and the main fault reasons of motorized spindle for NC machine tools are gotten. Qualitative analysis is performed for the fault tree by the mean of the structure function. At the end of this paper, the minimal cut sets which are the main sets of failure modes are all obtained. It has laid a good foundation for further study of quantitative analysis of motorized spindle failure modes.


2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Teng Xu ◽  
Qinxiang Xia ◽  
Xiaoyu Wu ◽  
Jiaqi Ran ◽  
Feng Gong ◽  
...  

By the multidomain modelling method, the vibration of a high-speed punching press was modelled and simulated, and the influence of the hydraulic system on the vibration of the punching press and the protection efficiency of the punching press under the overload condition was discussed. The multidomain simulation results were compared with the experimental results to the validity of the multidomain model on a punching press with a hydraulic system for vibration reduction function.


2019 ◽  
Vol 11 (6) ◽  
pp. 168781401985695 ◽  
Author(s):  
Jianfeng Ma ◽  
Chao Li ◽  
Jia Liu ◽  
Dongxing Cao ◽  
Jinfeng Huang

There is a nonlinear disturbance problem in the operation of large inertia load space-driving mechanism, which seriously affects the normal operation of the system. A 14 degree-of-freedom nonlinear time-varying dynamic model was established for a two-stage spur gear system. The dynamic equations were solved numerically based on the Runge–Kutta method. The correctness of the dynamic model was verified through experiments. In the author’s previous research, the transmission error and dynamic response of gear system was analyzed. After the establishment of the dynamic model, a comparative analysis of the load response under different inertia was performed to illustrate the importance of studying large inertia loads. A large inertia load transmission error experimental device was set up to collect and process the transmission error data under different load inertia and different speeds. Comparing experimental results with numerical results, the correctness of the numerical model was verified, and the reasons for the differences between the two were explained. The analysis of the experimental results shows that for the transmission error of large inertia load gear transmission system, the influence of stiffness excitation on the transmission error amplitude is dominant. For the high-speed gear system, the pitch error plays a dominant role.


Sign in / Sign up

Export Citation Format

Share Document