| 摘要 |
PROBLEM TO BE SOLVED: To provide a rolling bearing capable of reducing the noise and improving the production efficiency by making at least a rolling element out of ceramic, and specifying a defect area ration a maximum defect length and a maximum defect area on a surface of the rolling element respectively to be less than predetermined values. SOLUTION: An inner ring 2 and an outer ring 3 are made out of a bearing steel, and a plurality of balls 1 as rolling elements are made of a ceramic material. As the ceramic material, silicon nitride is used, and a surface of the ceramic ball 1 is controlled to have a defect area ratio of less than 0.2%, a maximum defect length of less than 8μm, and a maximum defect area of less than 40μm2. Whereby the bearing vibrational value can be surely controlled to be less than 40 mG, and the noise can be surely reduced. On this occasion, a yield rate is increased, the production efficiency can be improved, and the rolling bearing can be inexpensively manufactured without the excess quality.
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