Ball screw bearing is a type of bearing composed of screws, nuts, reverse devices, and balls used to convert rotary motion into linear motion or linear motion into rotary motion.

The ball screw pair has the characteristics of high precision, reversibility, and high efficiency, which is a further extension and development of the trapezoidal screw. The important significance of this development is to transform the sliding action of the trapezoidal screw into a rolling action.
Due to its small frictional resistance, ball screw bearings are widely used in various industrial equipment and precision instruments.