A bearing cage is disclosed that includes a first ring and a second ring with a plurality of crossbars extending therebetween to define a plurality of rolling element pockets. The first ring and the second ring each include a plurality of radially outward protrusions, a plurality of reliefs, and a plurality of axially extending protrusions extending into the plurality of rolling element pockets. The plurality of crossbars each include a plurality of retention tabs configured to engage rolling elements in the plurality of rolling element pockets.

A holder of a tapered roller bearing is made of a resin, has a first gap between an axially inner end surface of a small-diameter-side annular part and small-diameter-side end surfaces of tapered rollers, has a second gap between an axially inner end surface of a large-diameter-side annular part and large-diameter-side end surfaces of the tapered rollers, and is provided to be capable of moving within a prescribed range along the axial direction. The surface of the axially inner end surface of the large-diameter-side annular part is rough, the large-diameter-side annular part is provided with one or more grooves which are oil-holding parts that hold the lubricating oil, and ends of the grooves are positioned to be capable of coming into contact with the tapered rollers.

A cage for a tapered roller bearing includes a large-diameter-side annular portion circumferentially extending along large end surfaces of a plurality of tapered rollers; a small-diameter-side annular portion circumferentially extending along small end surfaces of the tapered rollers; and a plurality of pillars coupling together the large-diameter-side annular portion and the small-diameter-side annular portion. The large-diameter-side annular portion has large-diameter-side pocket surfaces opposed to the large end surfaces of the respective tapered rollers. The large-diameter-side pocket surfaces include oil retaining holes including blind holes, and being configured to receive and retain lubricating oil by capillary action.

In the tapered roller bearing, at least any one of an outer ring, an inner ring, and a plurality of tapered rollers includes a nitrogen enriched layer. An oil retaining hole is provided in a larger annular portion of a cage. A value of a ratio R/R.sub.BASE is not smaller than 0.75 and not greater than 0.87 where R represents a set radius of curvature of a larger end face of the tapered roller and R.sub.BASE represents a distance from a point which is an apex of a cone angle of the tapered roller to a larger flange surface of the inner ring. A ratio R.sub.process/R is than not lower 0.5 where R.sub.process represents an actual radius of curvature after grinding of the larger end face of the tapered roller and R represents a set radius of curvature.

A thrust roller bearing includes a plurality of rollers and a cage including a plurality of cage pockets for housing the rollers. The rollers each include a cylindrical portion, an outer crowning portion, and an inner crowning portion. The cage pockets each include an outer surface, an inner surface facing a second end surface of the roller, and a pair of side surfaces facing an outer peripheral surface of the roller. The side surfaces each include a recessed surface that is not contactable with the roller, and flat surfaces that are provided on the outer side in the radial direction and on the inner side in the radial direction, respectively, and are contactable with the roller. A first dimension is larger than a second dimension.

An inner ring unit includes an inner ring, a plurality of tapered rollers, and a cage having an annular shape. The cage includes a plurality of cage bars. The cage includes a stopper portion that is provided to protrude from an axial intermediate portion of the cage bar in the circumferential direction of the cage and configured to hinder the tapered rollers from falling off toward a radially outer side by bringing an axial intermediate portion on an outer peripheral surface of each tapered roller housed in a pocket into contact with the stopper portion. The axial intermediate portion on the outer peripheral surface of the tapered roller is a portion that is disposed on a one axial side and on the radially outer side of the tapered roller with respect to the center of gravity of the tapered roller.

A cage (110) for a roller thrust bearing (100), including a first cage half (120) including an annular portion (122), a first flange (130) extending axially from an inner peripheral edge (124) of the annular portion, and a second flange (132) extending axially from an outer peripheral edge (126) of the annular portion, and a second cage half (140) including an annular portion (142), a first flange (150) extending axially from one of an inner peripheral edge (144) and an outer peripheral edge (146) of the annular portion, a second flange (152) extending both axially and radially from the other of the inner peripheral edge and the outer peripheral edge, the second flange including a first flange portion (154) and a second flange portion (156), wherein the second flange portion of the second flange of the second cage half is disk-shaped and is disposed in a plane that is transverse to a longitudinal center axis of the roller retainer cage.

In a tapered roller bearing, a large-diameter-side annular portion includes large-diameter-side pocket surfaces opposed to large end surfaces of respective tapered rollers; and oil retaining recesses each having an opening spanning an inner peripheral surface of the large-diameter-side annular portion and each of the large-diameter-side pocket surfaces. Each of the oil retaining recesses has an inner surface having a radially inwardly facing surface portion which is an inclined surface that is radially inwardly inclined toward the corresponding tapered roller.

The present disclosure relates to a self-aligning roller bearing comprising an inner bearing ring, an outer bearing ring and at least one row of roller elements interposed in-between the inner and the outer bearing ring. The roller bearing further comprises a cage comprising a ring-formed first cage portion and a plurality of distributed cage pocket bars protruding axially outwardly from an axial side face of the first cage portion, delimiting a plurality of cage pockets for the roller elements. The side face comprises one or more protrusions adapted to respectively abut a portion of an axial end face of a respective roller element, which portion comprises at least a radial centre of the roller element.

A spherical roller bearing providing an inner ring, an outer ring, rollers for rolling on raceways arranged on the rings, and a cage for holding the rollers spaced apart from each other. The cage having an annular core and a plurality of bars delimitating a plurality of pockets for the rollers, the annular core including two side faces from which the bars protrude axially outwardly, the inner and outer rings being rotatable with respect to each other around a bearing axis. The annular core further provides a plurality of spacing elements that protrude from the side faces of the annular core designed to come into contact with side faces of the rollers in order to prevent the rollers from moving axially towards the center of the bearing.