Patent ID: 7530743

Claim:
A double row cylindrical roller bearing comprising: an outer race; an inner race; double rows of cylindrical rollers rotatably arrayed between the outer race and the inner race; pluralities of roller guide cages formed integrally out of synthetic resin for each row of the double rows of rollers, the cages comprising: an annular portion; and a plurality of columnar portions disposed circumferentially at predetermined intervals and projecting axially from a roller-side end surface of said annular portion; wherein the rollers are retained in pockets formed by bearing-circumferential opposite side surfaces of the columnar portions and the roller-side end surface of the annular portion, the double row cylindrical roller bearing being characterized in that: a tapered surface is provided on a back surface which is opposite the roller-side end surface of the annular portion, the tapered surface being formed in such a manner that an axial dimension of said back surface is reduced gradually from an inner diameter side of the annular portion to an outer diameter side of the annular portion, an outer side surface of the columnar portion is formed into a tapered surface in which a radial dimension of said columnar portion is reduced gradually as it approaches its axially front end, a straight surface formed on the bearing-circumferential opposite side surfaces of the columnar portion and being located on at least a part of a region on an inner diameter side of a pitch circle diameter, the straight surface not allowing contact pressure between the columnar portion and the cylindrical roller bearing when a free-end side of the columnar portion bends in a direction to expand its diameter due to centrifugal force; and a bearing-inner-diameter-side end portion of the bearing-circumferential side surfaces of the columnar portions retains grease.