TAPERED ROLLER BEARING

摘要

Provided is a tapered roller bearing in which occurrence of fretting is suppressed without a reduction in the fatigue life. The tapered roller bearing has an outer ring (23), an inner ring (22), tapered rollers (24) interposed between the outer ring (23) and the inner ring (22), and a retainer (25) for retaining the tapered rollers (24). The tapered roller bearing is used in an idler section of an automobile transmission where the state of the bearing is changed between an idle state in which the outer ring (23) rotates idle relative to the inner ring and a shift state in which the outer ring (23) rotates in synchronism with the inner rings (22). When the angle of an outer ring raceway surface is 2a and the angle of the roller is ß, a/ß = 4.9 is satisfied.