Influence of angular misalignment on the tribological performance of high-speed micro ball bearings considering full multibody interactions

To study the angular misalignment effects on the high-speed micro ball bearing which is applied to the dental handpiece, an improved five-degree-of-freedom quasi-dynamic model considering full multibody interactions is established in this paper. Then the modified fatigue life model presented by Jones is adopted to further evaluate the influence of angular misalignment on the reliability of the bearing. The results show that the angular misalignment significantly influences the contact load and contact angle distributions as well as the skidding behavior under both pure axial load and combined axial and radial loads. After comprehensive comparison, it is found that the impacts of angular misalignment on total power loss and bearing fatigue life are different under the two types of loads. Under pure axial load, the total power loss increases consistently and the bearing fatigue life decreases significantly when the absolute value of angular misalignment becomes larger. However, under combined axial and radial loads, the effects of angular misalignment are rather complicated and the direction of angular misalignment turns out to be a key influencing factor.