Patent ID: 8083598
Filing Date: 2011-12-27
Classification: B60B,B60K,F16C,F16D

Abstract:
1. A bearing device for a wheel comprising: an outer member having a plurality of outer races on an inner periphery; an inner member including a hub wheel integrally having a wheel attachment flange, at least one inner ring press fitted to an outer periphery of the hub wheel, and a plurality of inner races facing the outer races on an outer periphery; and a plurality of rows of rolling elements arranged between the outer races and the inner races facing each other; and a pilot portion for being fitted, to an inner periphery of a wheel, the pilot portion being arranged on a separate member other than the hub wheel, wherein: an outboard side end face of the wheel attachment flange is a flat surface at a position closest to the outboard side in the hub wheel; a nut housing portion is formed in the outboard side end face, the nut housing portion defining an opening and a seating surface surrounding the opening for contacting a nut member; the seating surface is located further inboard relative to an inboard side end face of the wheel attachment flange; and the nut housing portion includes a tapered circumferential surface having a smaller diameter at an inboard-side portion thereof, and the tapered circumferential surface is made smoothly continuous with the outboard side end face via an arc-shaped surface.