Abstract:In order to deeply analyze the influence of local failure of rolling ball bearing on the overall vibration characteristics of the bearing, a numerical simulation model of ball bearing-rotor system dynamics under rotor eccentric force excitation is constructed by using Hertz contact theory, and the impact excitation response equation between rolling body and various types of fault areas is deduced by combining the bearing clearance changes caused by local failure of outer ring, inner ring and rolling body of deep groove ball bearing. On this basis, by analyzing the change of internal contact load of balls caused by single-point damage, the influence law of single ball contact stress on the load of adjacent rollers and the overall vibration characteristics of the system is revealed. By analyzing the changes in the number of effective bearing balls during the bearing rotation, the relationship between the ball load occupancy time and the amplitude of fault impact oscillation is established. The analysis results show that the contact separation of the ball and the fault area causes its load to oscillate, and the oscillation frequency of each fault state is the system resonance frequency; the larger the running time share on the 2 equivalent load-bearing rollers, the greater the intensity of the fault shock oscillation. The Poincar- mapping point of each type of early fault state keeps near the same amplitude. When the degree of local failure increases to a certain degree, the chaotic characteristics of the system vibration are enhanced and the vibration amplitude increases accordingly.