Structure of NSK small ball bearings and miniature ball bearings

Structural type The so-called NSK small ball bearings and miniature ball bearings refer to the bearings in the size range shown in Table 1. The structure and structure code of these bearings are shown in Table 2, from which representative bearings are selected and listed in this catalog. (represented by in Table 2). Usually, small and miniature ball bearings use steel corrugated cages or crown cages. The wave-shaped cage is used for large bearings, and the crown-shaped cage is 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 Rotational Accuracy Metric Series Bearings ................................. Table 2.1 (A165 ), Table 2.2 (A167) Tolerance of the stop rib of the metric series bearing with stop rib, as shown in Table 4. The applicable conditions of use are shown in Table 4. Examples of bearing accuracy grades and matching conditions The dimensions of the shaft. Table 6 Fitting Notes of Inner Ring and Shaft ( 1 ) L: Clearance Fit T: Interference Fit (2 ) Usually glued after installation. The fit conditions for mounting the bearing to the machine are extremely important for the full performance of the machine. Since small, NSK miniature ball bearings are generally used under light load conditions, fits ranging from a small amount of interference to a slight clearance fit are used. In addition, in order to facilitate installation, prevent failure during installation, and avoid changes in contact angle and preload due to fit, clearance fit is sometimes selected. When a clearance fit is selected, the inner ring can be fastened to the shoulder with a nut etc. to prevent slippage. When the spring is used to preload the bearing, the fit of the ring supporting the preload side should be a clearance fit to ensure smooth axial movement. In order to reduce the weight of the equipment, when a light alloy bearing seat is used, the clearance of the outer ring mating surface will increase with the temperature rise, which may lead to the decline of equipment performance and early damage to the bearing. Therefore, it is best to use steel bushings. Examples of fits for general operating conditions are shown in Tables 6 and 7 (pages B58 and B59). For special applications, please consult NSK. In addition, refer to Table 8 and Table 9 (page B60) for the dimensional tolerances of the shaft and housing bore.