What role does the internal bearing of the motor play?

Update:20 Jan 2020
Summary:

The internal bearing of the motor should be a support, […]

The internal bearing of the motor should be a support, that is to say, it is used to support the shaft, but this is only part of its role. The essence of support is to be able to bear radial loads. Can also be understood as it is used to fix the shaft. The bearing selection of quick, easy and excellent automation is included. It is to fix the shaft so that it can only achieve rotation, and control its axial and radial movement. The motor cannot work without bearings. Because the shaft can move in any direction, the shaft can only be rotated when the motor is working. In theory, it is impossible to realize the role of transmission. Not only that, the bearing will also affect the transmission. In order to reduce this effect, good lubrication must be achieved on the bearings of high-speed shafts. Some bearings already have lubrication, called pre-lubricated bearings. Most bearings must be lubricated. When running at high speeds, friction not only increases energy consumption, it is even more terrible that the bearings are easily damaged. The idea of turning sliding friction into rolling friction is one-sided, because there is something called a sliding bearing.