Ball Bearing Stiffness Incorporating Bearing Ring Flexibility.

Abstract

An investigation was carried out to explain the ball bearing stiffness which took into account the bearing ring flexibility, and the relationship between the deformation of the bearing ring and the stiffness of the ball bearing under an axial load. In this study, first, the axial stiffness of the ball bearing under the axial load and the deformation of the outer ring were measured. Second, the calculation method of the bearing stiffness incorporating the bearing ring flexibility was proposed. Third, the validity of the presented calculation method was discussed. Fourth, the deformation of the bearing ring was discussed. From the results of experiments and analysis, the conclusions were obtained as follows: (1) The calculation method of the bearing stiffness incorporating the bearing ring flexibility was proposed. The axial stiffness of the ball bearing under the axial load can be estimated using the presented calculation method. (2) The outside surface of the outer ring of the bearing under the axial load causes a deformation in the pyramid with the polygonal number n. The polygonal number n is equal to the number Z of balls. The bottom face of the pyramid is where the axial load is applied. (3) The out of roundness of the periphery of the outer ring of the ball bearing under the axial load changes with the axial position of the outer ring. The axial position where the out of roundness is maximized coincides with the axial position of the contact point between the ball and the outer ring.