Research on mechanical characteristics of fault-free bearings based on centrifugal force and gyroscopic moment

This paper presents a quasi-static model of high-speed ball bearing, and the analytical expressions of dynamic stiffness are obtained. The action mechanism of centrifugal force and gyroscopic moment and its effect on kinematic and mechanical characteristics of bearing are studied. Results show that with the increase in rotational speed, centrifugal force increases continuously, while gyroscopic moment rapidly first and then slightly. With the increase in inertial force, the inner-ring contact angles and the outer-ring contact force increase, the outer-ring contact angles and inner-ring contact force decrease, and bearing stiffness will increase in all directions, while axial load will reduce the effect of inertial force. Radial force will increase the non-uniformity of load distribution, making the difference of load carried by each ball larger, thus aggravating the instability of the system. Compared with gyroscopic moment, centrifugal force is the main factor, while ignoring both inertial forces, rotational speed no longer affects mechanical characteristics of bearings. This study provides theoretical support for the dynamic analysis of high-speed bearing rotor system.