Patent ID: 8308371
Filing Date: 2012-11-13
Classification: B60B,F16C,Y02T

Abstract:
1. A bearing apparatus comprising: an outer member formed with double row outer raceway surfaces on its inner circumferential surface; an inner member including a wheel hub with a disk shaped wheel mounting flange integrally formed at one end continuously about a periphery of the inner member, a first plurality of apertures and a second plurality of circular apertures formed in the flange, the second plurality of circular apertures each have a diameter larger than the diameter of the first plurality of apertures, hub bolts are adapted to be mounted on the disk shaped wheel mounting flange equidistantly along an outer periphery of the disk shaped wheel mounting flange, an inner raceway surface is formed on an outer circumferential surface opposite to one of the double row outer raceway surfaces and a cylindrical portion axially extends from the inner raceway surface, a shaft-shaped portion has an outer diameter larger than a diameter of a bottom of an inner side inner raceway surface, an outer outline configuration of the wheel hub continues from the bottom of the inner raceway surface to the cylindrical portion via a counter portion, the shaft shaped portion axially extending from the counter portion, a taper shaped stepped portion, and a shoulder, a substantially conical recess is formed in an outer side end portion of the wheel hub, and the depth of the recess extends into the wheel hub past the outer side inner raceway surface and the conical recess terminates at the outer side of a shoulder of the wheel hub against which an inner ring abuts so that a substantially constant wall thickness is formed between the conical recess and the outer circumferential surface of the wheel hub of the outer side end portion and the wheel hub is solid under the inner side inner raceway surface; an inner ring is press fit onto the cylindrical portion abutting the shoulder, the inner ring is formed, on its outer circumferential surface, with the inner side inner raceway surface opposite to the other raceway surface of the double row outer raceway surfaces; double row groups of balls are freely rollably contained between the outer raceway surfaces and the inner raceway surfaces, respectively, of the outer member and the inner members; a pitch circle diameter of an outer side ball group is larger than a pitch circle diameter of an inner side ball group; and ribs are formed on a surface of the inner side of the disk shaped wheel mounting flange and each rib includes at least one aperture of said plurality of first apertures, each rib is formed by an outline including straight portions, radially extending outwardly from the base of the disk shaped wheel mounting flange, and a rounded tip portion, having a predetermined radius of curvature centered on an axial center of a hub bolt and substantially corresponding to a distance between the axial center and the outermost periphery of the disk shaped wheel mounting flange, the ribs have a substantially constant thickness in a radial direction and at least one circular aperture of said second plurality of circular apertures is positioned in a portion of the mounting flange between adjacent ribs for enabling tool access and the portion of the mounting flange between adjacent ribs is tapered radially outward so that its thickness gradually reduces radially outward.