Wheel bearing and a wheel bearing apparatus having the wheel bearing

Abstract

A vehicle wheel bearing forming a double row angular contact ball bearing of back-to-back duplex bearing type has an outer member formed, on its inner circumference, with outer raceway surfaces with each having a circular arc longitudinal section. A pair of inner rings are each formed, on its outer circumference, with an inner raceway surface having a circular arc longitudinal section arranged opposite to one of the outer raceway surfaces. The end of a smaller diameter side of one inner ring abuts against an end of a smaller diameter side of the other inner ring. Double row balls are contained between the outer and inner raceway surfaces, respectively, of the outer member and inner rings and are held by cages. Seals are mounted in annular openings formed between the outer member and inner rings. The outer member and the inner rings are made by plastically deforming pipe members, The outer and inner raceway surfaces, cylindrical portions of the outer member forming fitting portions of the seals and/or shoulder portions of the inner rings forming land portions are formed with predetermined dimensions and are ground for accuracy.