Rolling bearings are precision mechanical components that reduce friction loss by changing sliding friction between a rotating shaft and its seat to rolling friction. Rolling bearings generally consist of four parts: an inner ring, an outer ring, rolling elements, and a cage. The inner ring is used to fit with the shaft and rotate together with it; the outer ring is used to fit with the bearing seat and provide support; the rolling elements are evenly distributed between the inner and outer rings with the help of the cage, and their shape, size, and quantity directly affect the performance and life of the rolling bearing; the cage enables the rolling elements to be evenly distributed, guides them to rotate, and provides lubrication.