WHEEL BEARING UNIT, AND MANUFACTURING METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To prevent judder in applying a brake by suppressing the oscillation of a rotor fixed to a hub 8a, and to sufficiently ensure durability of a wheel bearing unit 5a. SOLUTION: A cylindrical surface part 30 is formed on an outer circumferential surface of a rotating side flange 13a provided on an outer circumferential surface of the hub 8a with the rotor fixed thereto. The outside diameter D30 of the cylindrical surface part is set to be larger than the diameter D12 of the maximum circumscribed circle of a fixed side flange 12 provided on an outer circumferential surface of an outer ring 6. The wheel bearing unit 5a to be ground is assembled to the outer side of the rotating side flange 13a, and fitted to a grinding machine. The periphery of a part from the outside diameter side of the cylindrical surface part 30 to the outside diameter side of the inner end of the hub 8a is covered by a cylindrical cover 42 fixed to the grinding machine. The outer surface of the rotating side flange 13a is ground while rotating the hub 8a to the outer ring 6.