Dynamic analysis of grinding electric spindle bearing-rotor system under eccentric action

To study the influence of eccentricity on the dynamic characteristics of grinding electric spindle, firstly, the nonlinear oil film force (NOFF) expression of sliding bearing is established based on the boundary condition of adhesion pressure. Then, the expression of the unbalanced magnetic pull (UMP) under the eccentricity of the air gap is derived. Finally, the bearing-rotor dynamics equation of the grinding electric spindle considering the NOFF and UMP is established, and the dimensionless processing is carried out. The nonlinear dynamics study of the bearing-rotor system under the influence of geometric eccentricity and mass eccentricity is carried out through the shaft center trajectory and the shaft center vibration spectrum. The research results can provide reference for the optimal design of grinding electric spindle.

Automated summary

In this study, the influence of eccentricity on the dynamic characteristics of grinding electric spindle was investigated. Nonlinear oil film force (NOFF) expression of the sliding bearing was established based on the boundary condition of adhesion pressure. The expression of unbalanced magnetic pull (UMP) under eccentricity of the air gap was derived. The bearing-rotor dynamics equation considering NOFF and UMP was established, and the nonlinear dynamics of the bearing-rotor system under the influence of geometric eccentricity and mass eccentricity were studied.