Analysis And Study On Supporting Stiffness Of High-speed Spindle System

The dynamical characteristics of the high-speed electricity main-shaft system are mostly determined by the stiffness performance of rolling bearing which support totor,especially radial stiffness and axial stiffhess.With the development of dynamics characteristic of shaft rotor, scientists and researchers pay more attentions to the stiffness analysis of high-speed rolling bearings. In this paper the practical engineering models of stiffness calculation for high-speed angular contact ball bearings are established. Using the language of VC, combining whith the Matlab and OpenGL, stiffness calculation for bearings are programmed.On the basis of the traditional quasistatic analytical methods, with the Finite Element Method (FEM), the supporting stiffness matrix of the bearings is added into the whole stiffness matrix of the shaft and the calculation and analytical method is build in the paper. Centrifugal forces and gyroscopic moment are taken into account in the analytical model and internal friction is neglected. Newton-Raphson iterative method is used to solve eauilibrium equations of balls and bearing in the analysis model and some equations are derived using numerical method.Using the stiffness calculation program for high-speed angular contact ball bearings, the bearing stiffness is calculated by high-speed electricity main-shaft bearings(model number is VEX35). Using the dynamic parameter during calculation the stiffness, the critical speed of the shaft and the life of the bearing are calculated. And the influence of the life, the speed, the stiffness and the lubrication on the system of the shaft are also considered.