Multiple Resonances and Nonlinear Behaviors of a Spindle Ball Bearings System with 3/2 Nonlinear Term

摘要

Considering the symmetry, the spindle ball bearings system can be simplified into a two-degree-of-freedom system and the three-term harmonic balance (THB) method is used to examine the complex, nonlinear dynamic behavior of the spindle-bearing system. The analytical results obtained by the THB method indicate the resonances are found at the one-third of the first natural frequency, one-half of the first nature frequency, two-third of the first natural frequency, and the first natural frequency in the spindle-bearing system with 3/2 stiffness nonlinearity. These results agree well with the results obtained by the time domain simulations. With the variation of the natural frequency of the system, the phenomena of the jump in frequency-response curves are observed. The bending of the frequency-response curves significantly increase with the increase of the contact stiffness of the bearing and the eccentricity of the spindle.