A tapered roller bearing includes an inner ring including, on its outer circumferential surface, an inner raceway surface and including, on an end portion on a second axial side, a cone back face rib portion protruding radially outward, an outer ring including, on its inner circumferential surface, an outer raceway surface, a plurality of tapered rollers disposed between the inner ring and the outer ring, and an annular cage that retains the plurality of tapered rollers spaced from each other in a circumferential direction. The cage includes a small-diameter annular portion, a large-diameter annular portion located on the second axial side relative to the tapered rollers and the outer ring, and a plurality of cage bar portions. The large-diameter annular portion has an oil pocket having a first aperture that is open radially inward and a second aperture that is open toward the outer raceway surface.

In a tapered roller bearing, a large rib is provided at one end of an inner ring in the axial direction, and projects radially outward. A lubricating oil holding member is integrated with an outer ring, and disposed at a position overlapping the large rib in the radial direction. The lubricating oil holding member includes a tubular portion and an annular portion. An inclined surface is disposed on the outer peripheral surface of the large rib at one end in the axial direction. The distance from the rotational axis of the inner ring to the inclined surface becomes larger from one side in the axial direction toward the other side. An end of the inclined surface is positioned, in the axial direction, between the annular portion and one end of the outer ring in the axial direction.

An integrated plastic shield bearing assembly including a plastic shield for preventing contamination of running surfaces of a bearing assembly is disclosed. The integrated plastic shield bearing assembly includes an inner bearing ring defining an inner race, an outer bearing ring defining an outer race, and a plurality of rolling elements supported between the inner race and the outer race. A first one of the inner bearing ring or the outer bearing ring includes a circumferential groove. The plastic shield includes a molding portion molded on to the circumferential groove of the first one of the inner bearing ring or the outer bearing ring, and a shield portion extending towards a second one of the inner bearing ring or the outer bearing ring.

In a tapered roller bearing, a large rib is provided at one end of an inner ring in the axial direction, and projects radially outward. A lubricating oil holding member is integrated with an outer ring, and disposed at a position overlapping the large rib in the radial direction. The lubricating oil holding member includes a tubular portion and an annular portion. An inclined surface is disposed on the outer peripheral surface of the large rib at one end in the axial direction. The distance from the rotational axis of the inner ring to the inclined surface becomes larger from one side in the axial direction toward the other side. An end of the inclined surface is positioned, in the axial direction, between the annular portion and one end of the outer ring in the axial direction.

A tapered roller bearing includes an outer ring having a first raceway surface, an inner ring having a second raceway surface, plural tapered rollers disposed between the first and second raceway surfaces, and a lubricating oil holding member fixed to an end portion of the outer ring. The lubricating oil holding member includes a tubular portion, an annular portion, and a projecting portion. The tubular portion is formed in the shape of a cylinder, and fixed to an end portion of the outer ring. The annular portion is formed in the shape of a circular ring. An end portion of the annular portion on the outer side is connected to an end portion of the tubular portion on one side. The projecting portion projects radially inward from the inner peripheral surface of the annular portion in the radial direction.

A self-lubricating assembly for a linear guideway comprises two oil containers and at least a connector. Each of the oil containers has a body, at least one absorber, and a flexible lubricating element. A holding groove for accommodating the lubricant is formed inside the body, the outside of the body is formed with a rail contacting portion and a connecting portion. The absorber is disposed in the holding groove for sucking the lubricant. The flexible lubricating element is disposed firmly in the rail contacting portion, and at least a part of the flexible lubricating element is extended to the holding groove for sucking the lubricant. The diffusion velocity of the lubricant in the absorber is faster than the diffusion velocity of the lubricant in the flexible lubricating element. At least a connector connects the connecting portions of the oil containers, so the lubricant flows between the two oil containers.

An integrated plastic shield bearing assembly including a plastic shield for preventing contamination of running surfaces of a bearing assembly is disclosed. The integrated plastic shield bearing assembly includes an inner bearing ring defining an inner race, an outer bearing ring defining an outer race, and a plurality of rolling elements supported between the inner race and the outer race. A first one of the inner bearing ring or the outer bearing ring includes a circumferential groove. The plastic shield includes a molding portion molded on to the circumferential groove of the first one of the inner bearing ring or the outer bearing ring, and a shield portion extending towards a second one of the inner bearing ring or the outer bearing ring.

An outer ring has an annular step provided on an outer peripheral surface of the outer ring and forming an annular thin walled portion at an axial end of the outer ring. An axially inward end surface of a tubular portion of a lubricant holding member contacts the step of the outer ring, and an inner peripheral surface of the tubular portion contacts an outer peripheral surface of the thin walled portion. An annular groove is formed at a coupling portion between the step of the outer ring and the outer peripheral surface of the thin walled portion.

A bearing assembly includes a casing, a rotatable shaft disposed in the casing, a bearing unit coaxially coupled between the rotatable shaft and the casing, and an oil seal arrangement. The oil seal arrangement includes an inner sealing member, and an outer sealing member, and an oil filling unit. The inner sealing member is coaxially extended from the rotatable shaft to the casing for enclosing the bearing unit within the casing and for sealing and retaining lubricant within the casing. The outer sealing member is coaxially extended from the rotatable shaft to the casing at a position apart from the inner sealing member to form an oil reserving chamber between the inner and outer sealing members for reserving a predetermined of reserved lubricant. The oil filling unit is formed at the casing to communicate with the oil reserving chamber for refilling the reserved lubricant thereinto.

A bearing device is constituted by a rolling bearing and a lubricant supply device combined with each other. The lubricant supply device includes a lubrication oil tank which stores pressurized lubrication oil and has a lubrication oil discharge spout; an open/close valve which opens/closes the lubrication oil discharge spout of the lubrication oil tank; a driving section which operates the open/close valve; and an electric power source section which generates electric energy for operation of the driving section. The lubricant supply device is attached to the rolling bearing or to a spacer adjacent thereto.