NEEDLE ROLLER BEARING AND BEARING STRUCTURE

摘要

A needle roller bearing (11) has an outer ring (13) having two outer ring members (12) split by a split line extending in the direction of the axis of the bearing; needle rollers (14) rollably placed on the raceway surface of the outer ring (13); and a retainer (15) for retaining the needle rollers (14). The curvature radius r1 of the outer ring members (12) and the curvature radius r2 at the outer circumference_{of the retainer (15) satisfy 1 < R1/r2 < 1.3.}