bearings

The design and manufacturing process control of the associated parts tolerance of the motor manufacturer plays a crucial role in the final use result. Today, we do a simple exchange on the tolerance relationship of bearing, shaft and bearing chamber radial size.

1. Select the factors to be considered

(1) Diameter of bearing inner ring and outer ring.

(2) The structural type of bearings, such as radial bearings, angular contact bearings, cylindrical roller bearings, etc.

(3) The accuracy level of the bearing, such as po, p5, p6, etc.

(4) Other factors

<1> When the bearing is working, due to the influence of friction heat and other heat sources, the temperature of the bearing ring is higher than that of its matching parts. As a result, the match between the bearing inner ring and the shaft may become loose. The fit between the outer ring and the housing hole may become tight, so when the working temperature of the bearing is high, the selected fit should be properly corrected.

<2> When the rotation speed of the bearing is high and the bearing is working under the impact vibration load, it is best to choose interference fit between the bearing and the shaft and the bearing chamber.

<3> When the bearing bears large loads or bears vibration and impact loads, its interference amount is appropriately increased. When hollow shaft, thin wall or plastic bearing chamber is used, the interference amount should be appropriately increased.

2. Correlation accuracy matching relationship

The tolerance grade of shaft bearing position and bearing chamber should be increased correspondingly with the improvement of bearing tolerance grade, rotation accuracy and motion stability. Taking into account the influence of shaft and bearing chamber on bearing accuracy and the difficulty of processing, the processing accuracy of general shaft is the same level of bearing accuracy or higher accuracy, and the bearing chamber is the lower level of accuracy or the same level of accuracy.

3. Rotation conditions and matching methods

The rotating condition refers to the bearing ring relative to the load, which is divided into rotating load, static load and indefinite load.