An annular cage provided with a taper roller bearing includes: a small-diameter annular portion, a large-diameter annular portion, and a plurality of column portions which link the small-diameter annular portion and the large-diameter annular portion to each other, and further includes roller retaining portions which prevent taper rollers accommodated in pockets from falling out to the outer side in the radial direction. Each of the roller retaining portions has a shape of a protruding beam that is a fixed end on the column portion side and on the small-diameter annular portion side, extends in the circumferential direction and in a column portion longitudinal direction, and is a free end on the tip end side in the extending direction.

A taper roller bearing includes: an inner ring, an outer ring, a plurality of taper rollers, and an annular cage. The cage includes a small-diameter annular portion on one side in a axial direction, a large-diameter annular portion which is positioned on the other side in the axial direction and on a radial outer side of a large flange of the inner ring, and a plurality of column portions which link the small-diameter annular portion and the large-diameter annular portion. The taper roller bearing has a labyrinth structure which suppresses a flow of lubricating oil to the outside of the bearing from the inside of the bearing between the large flange and the large-diameter annular portion.

A taper roller bearing includes: an inner ring, an outer ring, a plurality of taper rollers, and an annular cage which holds the plurality of taper rollers at an interval in the circumferential direction. The cage includes a small-diameter annular portion on one axial side, a large-diameter annular portion on the other axial side, and a plurality of column portions. An inner circumferential surface of the small-diameter annular portion includes a first inner circumferential surface portion and a second inner circumferential surface portion having a small diameter. An outer circumferential surface of the small flange included in the inner ring includes a first outer circumferential surface portion which opposes the first inner circumferential surface portion having a fine clearance, and a second outer circumferential surface portion which has a small diameter and opposes the second inner circumferential surface portion having a fine clearance.

A rolling bearing includes an inner ring, an outer ring, a plurality of rolling elements arranged between a raceway surface of the inner ring and a raceway surface of the outer ring, and a cage that holds the rolling elements at intervals in a circumferential direction. The raceway surfaces have a contact angle with each of the rolling elements. An area of clearances formed among the inner ring, the outer ring, the rolling elements, and the cage as axially viewed from an axially first side of the raceway surfaces that is a small diameter side of the raceway surfaces is larger than an area of clearances formed among the inner ring, the outer ring, the rolling elements, and the cage as axially viewed from an axially second side of the raceway surfaces that is a large diameter side of the raceway surfaces.

A roller-cage assembly including rolling elements and a cage is provided. The cage includes crossbars extending between an inner and outer ring that define rolling element pockets. Each of the crossbars is tapered from a larger width at the radially outer ring to a smaller width at the radially inner ring, and is connected to the radially inner ring at a first cross-sectional connection area. The crossbars have a first and second lateral surface for supporting the rolling elements. The first cross-sectional connection area of each of the crossbars has a minimum width and a first height. A maximum distance is defined between outer surfaces of adjacent rolling elements and is greater than zero. The minimum width of the first cross-sectional connection area is greater than the maximum distance defined between outer surfaces of adjacent rolling elements at radially inner ends thereof, and is 30-50% of the first height.

Provided is a resin cage for a tapered roller bearing in which a mold parting line which is extended in an axial direction is formed in a pillar portion defining a pocket. On facing surfaces of adjacent pillar portions, on an outer diameter side from the mold parting line, a first conical surface which slides in contact with an outer peripheral surface of a tapered roller is formed, and a first flat surface in a radial direction is formed in a portion on the outer diameter side from the first conical surface. On an inner diameter side from the mold parting line, a second conical surface which slides in contact with the outer peripheral surface of the tapered roller is formed, and a second flat surface in a radial direction is formed in a portion on the inner diameter side from the second conical surface

A cage made of a resin includes: a small-diameter annular portion on one side in an axial direction; a large-diameter annular portion on the other side in the axial direction; and a plurality of column portions which link the small-diameter annular portion and the large-diameter annular portion to each other. Spaces which are formed between the large-diameter annular portion and the small-diameter annular portion and between the column portions adjacent to each other in the circumferential direction are pockets which hold the taper rollers. A surface of the entire cage including the small-diameter annular portion, the large-diameter annular portion, and all of the column portions is configured by aggregating a surface viewed from the one axial side and a surface viewed from the other axial side.

A cage for a radial bearing assembly with rolling elements is provided. The cage includes a first and second rims, and webs extend between the rims to define pockets that receive rolling elements. Each of the webs includes first and second rolling element guide surfaces that face a first adjacent one of the pockets and third and fourth guide surfaces that face a second adjacent one of the pockets. These guide surfaces are located at a pitch circle adapted to coincide with a centerline of the rolling elements located in the pockets. The webs have first and second radially inner retention tabs that respectively face the first and second adjacent ones of the pockets. The first retention tab is located axially between the first and second guide surfaces and the second retention tab is located axially between the third and fourth guide surfaces. The retention tabs are located radially inside the pitch circle.

A rolling bearing retainer which is formed by insert molding a resinous material together with a core member within a mold, in which the core member is embedded within a resin part made of the resinous material and a support area exposure part is provided at a plurality of locations of the resin part for exposing a support area of the core member supported within a cavity of the mold. The resin part includes a ring shaped body and a plurality of support column bodies extending axially from the ring shaped body and defining a pocket for retaining a rolling element therebetween, and the core member is provided with a ring shaped body embedded part and a plurality of support column body embedded parts extending from the ring shaped body embedded part.

A taper roller bearing includes: an inner ring, an outer ring, a plurality of taper rollers in which a cavity portions are formed on a large end surface, and an annular cage. The cage includes a small-diameter annular portion on one axial side, a large-diameter annular portion which is positioned on the other axial side and on the outer side in the radial direction of the large flange, and a plurality of column portions. An outer diameter of an axial inner surface included in the large-diameter annular portion is greater than a diameter of a virtual circle that links outer end portions in the radial direction of the cavity portions of the plurality of taper rollers.