US Patent 7950858 Bearing apparatus for a wheel of vehicle

A vehicle wheel bearing apparatus has an outer member formed with a body mounting flange on its outer circumferential surface. The body mounting flange is to be mounted on a knuckle of the vehicle. The outer member inner circumference includes double row outer raceway surfaces. An inner member includes a wheel hub with a wheel mounting flange formed on one end. A cylindrical portion extends from the wheel mounting flange. At least one inner ring is press-fit onto the cylindrical portion of the wheel hub. The inner ring outer circumference is formed with an inner raceway surface arranged opposite to the double row outer raceway surfaces. Double row rolling elements are freely rollably contained between the outer raceway surfaces and inner raceway surfaces of the outer member and the inner members. Seals are mounted within annular openings formed between the outer member and the inner member. The inner ring is axially secured relative to the wheel hub by a caulked portion. The caulked portion is formed by radially outwardly plastically deforming the end of the cylindrical portion of the wheel hub. Outer side rolling elements of the double row rolling elements are balls. The inner side rolling elements of the double row rolling elements are tapered rollers. The fundamental rated load of the inner side row of tapered rollers is set larger than that of the outer side row of balls.