Modeling and Analysis of the Composite Stiffness for Angular Contact Ball Bearings

Abstract

As a core component of the motorized spindle, the dynamic stiffness of the angular contact ball bearing directly affects the dynamic characteristics of machinery. A modified quasistatic model of the ball bearing is established considering the influences of thermal deformation, centrifugal deformation, and elastohydrodynamic lubrication (EHL). Then, the film stiffness model considering spin motion is constructed. On this basis, the composite stiffness model of the ball bearing is proposed, and the effects of different factors on dynamic characteristic parameters are investigated. The results show that different factors have different effects on the dynamic parameters. With the increase in preload, the contact stiffness and composite stiffness increase. Considering EHL, the radial contact stiffness and composite stiffness increase while the axial and angular contact stiffness and composite stiffness decrease. Considering the thermal effect and centrifugal effect, the radial contact stiffness and composite stiffness increase while the axial and angular contact stiffness and composite stiffness decrease. The film stiffness and composite stiffness increase with the consideration of the spinning motion.