Rolling bearing frame is composed of an outer ring, inner ring, generally keep rolling body and. The inner ring and the shaft neck is the basic hole system (basic deviation of a hole tolerance zone, with different basic deviation tolerance zone of the shaft to form a system of various matching), outer ring and bearing chamber hole Weiji shaft system (basic deviation of a certain tolerance zone of the shaft, the hole with different basic deviations the tolerance zone formed a kind of system with various matched). When working, the rolling body, the outer ring raceway rolling, rolling friction. Rolling bearing has the advantages of small friction, small axial size, convenient replacement and easy maintenance and so on, so in the small induction motor, widely use rolling bearing.