| 摘要 |
A vehicle wheel bearing apparatus has an outer member formed, on its inner circumference, with double row outer raceway surfaces. An inner member is formed on its outer circumference surface, with double row inner raceway surfaces arranged opposite to the double row outer raceway surfaces. Double ball groups are freely rollably contained between the outer raceway surfaces and inner raceway surfaces, respectively, of the outer member and the inner member. It is formed as a double row angular contact ball bearing of back-to-back duplex type where a predetermined contacting angle is applied to each ball. A pitch circle diameter of the outer-side ball group is larger than a pitch circle diameter of the inner-side ball group. The outer-side groove diameter of curvature ratios are smaller than inner-side groove diameter of curvature ratios. |
