| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a deep groove ball bearing such that balls can be completely prevented from riding shoulders, and that the rolling fatigue life is long. <P>SOLUTION: Balls 31 are installed between a raceway groove 12 of an outer race 11 and a raceway groove 22 of an inner race 21. The balls 31 are retained in a cage 40. A total of four shoulders are formed on both sides of the outer raceway groove 12 and the inner raceway groove 22. As regards these four shoulders, the heights of a pair of shoulders 13a, 23b, which are located diagonally, are set to be higher than those of the remaining pair of shoulders 13b, 23a. The height of the higher shoulder 13a of the outer race 11 is denoted by H<SB POS="POST">1</SB>, the height of the higher shoulder 23b of the inner race 21 is denoted by H<SB POS="POST">2</SB>, and the diameter of the balls 31 is denoted by d. On the basis of these notations, a ratio H<SB POS="POST">1</SB>/d, which is the ratio of the shoulder height H<SB POS="POST">1</SB>of the outer race 11 to the diameter d of the balls 31, is set to be within a range of 0.28-0.50. Furthermore, a ratio H<SB POS="POST">2</SB>/d, which is the ratio of the shoulder height H<SB POS="POST">2</SB>of the inner race 21 to the diameter d of the balls 31, is set to be within a range of 0.37-0.50. As a result, the balls 31 are prevented from riding inner and outer race shoulders. Bearing steel which is the raw material for the outer race 11 and the inner race 21, is heat treated, resulting in the rolling fatigue life being improved. <P>COPYRIGHT: (C)2012,JPO&INPIT |
