Patent ID: 8360655

Claim:
A bearing device for a wheel, comprising: a bearing comprising double-row rolling elements arranged between outer raceways and inner raceways opposed to each other; a hub wheel for attachment to a wheel; a constant velocity universal joint; and a recess-projection fitting structure through which the hub wheel and a shaft section of an outer joint member of the constant velocity universal joint are separably coupled with each other, the shaft section being inserted in a fitting manner into a hole portion of the hub wheel, wherein the recess-projection fitting structure comprises: projecting portions extending in an axial direction provided on one of an outer surface of the shaft section of the outer joint member and an inner surface of the hole portion of the hub wheel, the projecting portions being press-fitted along the axial direction into another of the outer surface of the shaft section of the outer joint member and the inner surface of the hole portion of the hub wheel; and recessed portions formed through press-fitting of the projecting portions in the another of the outer surface of the shaft section of the outer joint member and the inner surface of the hole portion of the hub wheel so as to be held in close contact with the projecting portions in a fitting manner, the projecting portions and the recessed portions being held in close contact with each other through an entire region of fitting contact regions therebetween, wherein the recess-projection fitting structure allows separation caused by application of a pulling-out force in the axial direction, and wherein the hole portion of the hub wheel is provided with an inner wall serving as a bearing surface of a bolt for fixing the constant velocity universal joint.