Structure·Type The so-called miniature ball bearings and miniature ball bearings refer to the bearings within the size range shown in Table 1. The structure and structure codes of these bearings are shown in Table 2. Representative bearings are selected and listed in this catalog. (Indicated by in Table 2). Usually, small, miniature ball bearings use steel corrugated cage or crown cage. Wave-shaped cages are used for large bearings, and crown-shaped cages are used for small bearings. In addition, in recent years, crown-shaped plastic cages that are more conducive to torque, grease life and noise have been used. The type, code and name of the cage are shown in Table 3. Dimensional accuracy and rotation accuracy of metric series bearings....................................... Table 2.1 ( A165), Table 2.2 (A167) The tolerances of the stop ribs of the metric series bearings with stop ribs, as shown in Table 4, are suitable for the conditions of use. Examples of bearing accuracy grades match the size of the shaft. Table 6: Inner ring and shaft fit Note (1) L: Clearance fit T: Interference fit (2) After installation, it is usually glued. The matching conditions for installing the bearing on the machine are extremely important to give full play to the machine's performance. Since small and miniature ball bearings are generally used under light load conditions, the fit ranges from small interference to slight clearance fit. In addition, in order to facilitate installation, prevent failure during installation, and avoid changes in contact angle and pre-tightening force due to fit, sometimes clearance fit is selected. When choosing a clearance fit, you can fasten the inner ring on the shaft shoulder with a nut or the like to prevent slippage. When a spring is used to preload the bearing, the fit of the supporting preload side ferrule should be a clearance fit to ensure smooth axial movement. In order to reduce the weight of the equipment, when using light alloy bearing housings, the clearance of the mating surface of the outer ring will increase with the rise of temperature, and may cause the equipment performance to decline and early damage to the bearing. Therefore, it is best to use steel bushings. Examples of general working conditions are shown in Table 6 and Table 7 (pages B58 and B59). When used in special conditions, please inquire. In addition, refer to Table 8 and Table 9 (page B 60) for the dimensional tolerances of the shaft and the bearing housing hole.