1. Accuracy improvement method

After the bearing is installed in the host, if you measure the radial runout of the spindle, you can find that the measured value of each revolution has a certain change; when the measurement is performed continuously, it can be found that the change will be approximately repeated after a certain number of revolutions. appear. The indicator to measure the degree of this change is the cyclic rotation accuracy. The number of revolutions required for the approximate repetition of the change represents the "quasi-period" of the cyclic rotation accuracy. The magnitude of the change in the quasi-period is large, which is the poor cyclic rotation accuracy . If the main shaft is properly preloaded, the speed is gradually increased to close to the working speed to implement the "run-in" function of the bearing, which can improve the cycle rotation accuracy of the main shaft.

2. A method to improve bearing accuracy

A factory trial-produced precision instruments. The main shaft uses a 6202/P2 bearing and its accuracy still cannot meet the requirements. After that, the journal is thickened and raceways are made on it to replace the inner ring. The glutinous density of the balls is measured. Each group of three steel balls is separated by a distance of close to 120°. As a result of the reduction of one processing surface, another reduction of the mating surface, and the improvement of the shaft-bearing system Rigidity, and the close equidistant distribution of the largest three grains and the smallest three steel balls improves the rotation accuracy of the shaft, thus meeting the accuracy requirements of the instrument.

3. Comprehensive verification method for installation accuracy

After the angular contact ball bearing is installed in the spindle, the installation accuracy verification sequence is as follows (take the shaft diameter as 60—value="100" hasspace="False" negative="False" numbertype= "1" tcsc="0" w:st="on">100mm ordinary lathe as an example)