| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ball bearing of low torque, low heat generation, and a long service life. <P>SOLUTION: This deep-grooved ball bearing 1 is provided with an inner ring 2 and an outer ring 3 having raceway grooves 2a and 3a having arc-shaped cross sections, and a plurality of balls 4 rotatably disposed between the inner ring 2 and the outer ring 3. The groove radius of the inner ring 2 is set at 50.5% or more and 52% or less of the diameter of the ball 4, and the groove radius of the outer ring 3 is set at 52.5% or more and 55% or less of the diameter of the ball 4. At least the inner ring 2, among the inner ring 2, the outer ring 3, and the ball 4, is composed of carbonitriding-treated high carbon steel containing carbon of 0.9 mass% or more. <P>COPYRIGHT: (C)2004,JPO |
