THEORY OF MUM FOR METAL SPHERICAL ROTOR WITH CONTACTLESS SUSPENSION

作     者：He Xiaoxia Gao Zhongyu Wang Yongliang Department of Precision Instruments and Mechinery,Tsinghua University,Beijing 100084, China 

作者机构：Department of Precision Instruments and Machinery Tsinghua University Beijing 100084 China 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2004年第17卷第2期

页      面：243-246页

核心收录：

学科分类：0817[工学-化学工程与技术] 08[工学] 0807[工学-动力工程及工程热物理] 080203[工学-机械设计及理论] 0802[工学-机械工程] 0811[工学-控制科学与工程] 0801[工学-力学（可授工学、理学学位）] 

基　　金：This project is supported by National Defense Foundation of China (No.9.4.4) 

主　　题：Mass unbalance measurement Radical mass unbalance Axial mass unbalance Static balancing Averaging method 

摘      要：Based on the motion equations of an unbalanced spherical rotor withcontactless suspension, three methods of MUM (mass unbalance measurement) are put forward to measurethe total mass unbalance, radical mass unbalance and radical mass unbalance of the rotor. Totalmass unbalance is obtained when the unbalanced rotor plays as a simple pendulum in static *** pendulant period and pendulant midpoint indicate magnitude and direction of total massunbalance of the rotor respectively. Analysis of the motion equations by using the averaging methodyields that the rotor will do a special side oscillation when an auxiliary system makes the rotorspin about its pole axis which is orientating toward the local vertical. The radical mass unbalancecan be obtained by building a proper displacement sensor to sense the amplitude of the sideoscillation. Necessary analysis of the motion equations also shows that when the rotor spins at asmall angular velocity and the rotary axis is perpendicular to the vertical, the pole axis of therotor will precess slowly about the vertical by virtue of the axial mass unbalance. The axial massunbalance can be estimated from the time history of the spin vector of the rotor. Finally,measurement precision of the three methods is compared and how the external torque affects themeasurement precision for the three methods are examined.