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.

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 rolling element for a roller bearing. The rolling element may include a metal substrate having a surface layer. A portion of the surface layer may include a hardened nitrided layer. A diamond-like carbon (DLC) coating may be bonded directly on at least a portion of the hardened nitrided layer.

A tapered roller bearing for an automobile includes an inner ring including a raceway surface having a tapered shape on an outer periphery, an outer ring including a raceway surface having a tapered shape on an inner periphery, a plurality of tapered rollers incorporated into a space defined between the raceway surfaces, and a retainer configured to receive the tapered rollers. The inner and outer rings are each made of carburized steel, and the raceway surfaces of the inner and outer rings each have a straight generating line shape. The tapered rollers each are made of high carbon chromium bearing steel, and each have a rolling surface including a straight portion, which is formed at a center portion in an axial direction, and crowning portions, which extend from the straight portion to both end portions. The crowning portions are each formed of logarithmic crowning.

A roller for a roller bearing has a first end surface and a second end surface and a rolling surface between the first and second end surfaces. The first end surface has an at least partially ground profile having a non-constant curvature such as a logarithmic profile. Also, an assembly including a grinding tool and a roller with an end surface having a ground non-constant curvature.

An object of the present invention to provide a tapered roller bearing in which a flange portion is formed at a large-diameter end of an outer ring track surface of an outer ring, capable of providing high moment stiffness and long life without extremely decreasing its pure axial load capacity. The tapered roller bearing comprising: an outer ring 12 having an outer ring track surface 12a on its inner circumferential surface; an inner ring 13 having an inner ring track surface 13a on its outer circumferential surface; a plurality of tapered rollers 14 rotatably disposed between the outer ring track surface 12a and the inner ring track surface 13a; and a retainer 15 having a plurality of pockets for retaining the plurality of tapered rollers 14 at a predetermined interval; the outer ring track surface 12a of the outer ring 12 having a small-diameter end and a large-diameter end, the inner ring track surface 13a of the inner ring 13 having a small-diameter end and a large-diameter end, and, of these four ends, a flange portion 12b that protrudes radially inwardly is formed at the large-diameter end of the outer ring track surface 12a of the outer ring 12; wherein the tapered roller bearing has a contact angle greater than 35° and a roller angle not greater than 3.5°.

Two projecting portions (45a and 45b) configured to guide a tapered roller (3) on distal end surfaces thereof are formed on a side surface (43a) of a pillar portion (43) of a retainer (4) so as to be separated apart from each other in a roller axis direction. The projecting portions (45a and 45b) are separated apart from each other in the roller axis direction with respect to both a small-diameter-side annular portion (41) and a large-diameter-side annular portion (42). The projecting portions (45a and 45b) each have a force-fit margin (F).

A bearing assembly includes a split inner race ring configured to be installed on a shaft and defines two raceways for supporting rolling elements. A split clamping band is configured to be installed over the split inner race ring to secure the split inner race ring on the shaft. A split seal wear ring is configured to be installed on an outer diameter surface of the split clamping band. An engagement interface between the split clamping band and the split seal wear ring includes a boss on one of the split clamping band and the split seal wear ring, and an aperture on the other one of the split clamping band and the split seal wear ring. The aperture is sized and configured to receive the boss for positioning the split seal wear ring on the split clamping band.

The invention relates to an angular contact roller bearing having an inner ring and an outer ring, between which two or more raceways for a plurality of rolling elements are formed, the rolling elements being designed to roll in their respective raceways in the circumferential direction of the angular contact roller bearing, and the raceways and the rolling elements having cross-sections corresponding to one another at least approximately. A cross-section of a rolling element containing the central longitudinal axis has an at least approximately rectangular design and an imaginary diagonal through the cross-section of the rolling element which for all rolling elements on a raceway of the angular contact roller bearing is arranged on an imaginary surface at least approximately in the form of a cylindrical casing. The ratio of a transverse dimension of the rolling element to its length is characteristic of an angle at which the raceway of the rolling element is inclined relative to the central longitudinal axis of the angular contact roller bearing.

A tapered roller bearing for an automobile includes an inner ring including a raceway surface having a tapered shape on an outer periphery, an outer ring including a raceway surface having a tapered shape on an inner periphery, a plurality of tapered rollers incorporated into a space defined between the raceway surfaces, and a retainer configured to receive the tapered rollers. The inner and outer rings are each made of carburized steel, and the raceway surfaces of the inner and outer rings each have a straight generating line shape. The tapered rollers each are made of high carbon chromium bearing steel, and each have a rolling surface including a straight portion, which is formed at a center portion in an axial direction, and crowning portions, which extend from the straight portion to both end portions. The crowning portions are each formed of logarithmic crowning.