RV reducer is designed based on cycloidal pin wheel transmission principle, adopts two-stage deceleration and center disk support structure, has the characteristics of large transmission ratio, high efficiency, high precision, small return difference, low vibration, strong rigidity and high reliability, etc., is the core component of robot transmission system. Bearings play a role in precise positioning in the reducer, requiring large output torque, high precision, high load capacity, small volume, light weight, high rigidity, low noise, long life, smooth operation and safe and reliable characteristics to adapt to the harsh working environment and continuous work needs, and has good impact resistance. This kind of bearing is widely used in robots, welding positioner, CNC machine tool and precision radar transmission control and other fields requiring compact space and high-speed specific transmission.