| 摘要 |
PROBLEM TO BE SOLVED: To provide a bearing device for a wheel, which suppresses the hoop stress of an inner ring accompanied with caulking work, and achieves lower friction of a bearing by suppressing a gap range after caulking.SOLUTION: In a bearing device for a wheel of a third generation structure in which an inner ring 5 is fixed in the axial direction by a caulking part 4c which is formed by plastically deforming the end of a small-diameter part 4b of a hub wheel 4 to the outside in the radial direction in a state that the inner ring 5 is applied with a prescribed bearing pre-load, a wall thickness h1 at the side of a small end face 5b of the inner ring 5 is set larger than a step H of a shoulder 16 of the hub wheel 4, and an area A1 at the side of the small end face 5b is set not smaller than 11 of the internal diameter d of the inner ring 5, and also set so as to be arranged within an axial range L2 from an axial position corresponding to a position of the outer side of a ball 3 up to an axial position corresponding to a groove bottom position of the inside rolling face 5a of the inner ring 5. Consequently, sensitivity of the elastic deformation of the inner ring 5 at caulking work is lowered, a variation of a gap after caulking is suppressed, and lower friction of the bearing can be achieved. |
