To provide a bearing device for a wheel reduced in weight, size, and cost and, improved in sealability and bearing accuracy.

The bearing device for a wheel of first generation structure constituted of a hub wheel 1 of which one end integrally includes a wheel mounting flange 5, and a double-row angular contact ball bearing of a back-to-back type. An outer member 7 and an inner ring 8 are formed of pipe members by cold rolling. Seals 11 are fitted in cylinders 13 formed at both ends of the outer member 7, shoulders 14 which are axially extended are formed to ends on large diameter sides of the inner ring 8, and seal lips of the seals 11 are brought into slide-contact with the shoulders 14. Both rolling surfaces 7a, 8a, the cylinders 13 of the outer member 7 as fitting surfaces of the seals 11, and the shoulders 14 of the inner ring 8 as lands of the seals 11 are formed into predetermined dimensions and accuracy by grinding. Therefore, reduction in weight, size, cost, and improvement in sealing performance and bearing accuracy are achieved.

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