Patent ID: 8777489

Claim:
A ball bearing comprising: an inner ring comprising a raceway surface on an outer circumferential surface thereof; an outer ring comprising a raceway surface on an inner circumferential surface thereof; a plurality of balls rollably disposed between the raceway surface of the inner ring and the raceway surface of the outer ring; a cage configured to retain the plurality of balls at intervals in a circumferential direction, the cage being a crown type cage comprising a base portion and a plurality of pillar portions protruded on an axial end face of the base portion, the bails being accommodated in spherical pockets formed between the pillar portions; and an annular lubricant guide fixed to an axial end portion of the outer ring and extending towards a shoulder portion of the inner ring, wherein an annular opening portion is formed between an inner circumferential portion of the lubricant guide and the outer circumferential surface of the inner ring to supply lubricating oil into an interior of the ball bearing, and wherein the ball bearing is used under an environment in which the lubricating oil is supplied from one side in an axial direction with respect to the balls and is discharged from the other side in the axial direction with respect to the balls, wherein the lubricant guide is provided only on said one side in the axial direction, the other side being an annular opening extending radially between the outer ring inner circumferential surface and the inner ring outer circumferential surface, and wherein the base portion of the cage is disposed to face said one side in the axial direction.