A spacer includes a first surface and a second surface. The first surface and the second surface respectively have two opposite first roller accommodating grooves and two opposite second roller accommodating grooves. The first and second roller accommodating grooves of the first surface correspond to the second and first roller accommodating grooves of the second surface. The spacer defines a reference plane, which is perpendicular to a horizontal direction and passes through a center point of the maximum thickness of the spacer. The horizontal distance from the reference plane to the center of each first roller accommodating groove is different from the horizontal distance from the reference plane to the center of each second roller accommodating groove. By flipping the spacer of the present invention, the spacing of two adjacent rollers can be adjusted. In addition, the present invention further provides a cycloidal reducer with the aforementioned spacer.

A bearing unit provided with a radially outer ring, a radially inner ring, a plurality of rolling bodies interposed between the radially outer ring and the radially inner ring, and a retention device for keeping in position the plurality of rolling bodies, having a circular base rib, a plurality of fingers circumferentially spaced and defining a plurality of cavities for holding respective rolling bodies of the plurality of rolling bodies which are in contact with the retention device by means of a contact surface, and a plurality of discontinuity elements which reduce the extent of the area of contact with the rolling bodies.

A method of lubricating a bearing, a bearing, and a lubricant with high thermal conductivity including a base oil, a polymeric thickener, and thermally conductive powder particles. The lubricant is, at atmospheric pressure, liquid above a transition temperature and a gel below said transition temperature.

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 bearing assembly includes inner and outer rings, a plurality of rolling elements between the rings and first and second lubricant retainers. Each one of the first and second retainers includes an annular body having an outer radial end coupled with the outer ring and an inner radial end spaced radially and/or axially outwardly from the inner bearing ring such that an annular gap is defined between the inner radial end of each retainer and the bearing inner ring. The first retainer is disposed at least generally adjacent to a first axial end of the outer ring and the second retainer is disposed at least generally adjacent to a second axial end of the outer ring. The first and second retainers retain a quantity of liquid lubricant within the bearing annular space and the annular gap is sized to permit lubricant to be directed into the bearing annular space.

The present invention provides a bearing cage for a rotor bearing of a turbomolecular pump. The bearing cage comprises a plurality of bearing pockets each of which, in use, houses a bearing ball such that the bearing ball operably engages an inner race and an outer race of the rotor bearing. Each bearing pocket of the bearing cage has a primary chamber for housing the bearing ball and each bearing pocket further comprises a sump.

A full-complement anti-friction bearing is disclosed which includes a plurality of rolling elements, an inner bearing body in the form of a shaft or an axle with a cylindrical outer diameter, and an outer bearing body arranged concentrically with the latter and having an inner bore. In an exemplary embodiment, all rolling elements have the same outer diameter and are arranged between the inner bearing body and the outer bearing body in such a way that the rolling elements roll on the outer diameter of the inner bearing body and on the inner bore of the outer bearing body, the outer bearing body being thus rotatably supported relative to the inner bearing body. In addition, the full-complement anti-friction bearing is configured without a cage.

A roller and cage assembly includes: a cage (12) including a pair of rings (11) and a plurality of cage bars (21) extending in an axial direction and connecting the rings (11) to each other; and rollers disposed in pockets between the cage bars (21, 21) adjacent to each other in a circumferential direction. The cage bar (21) includes an end portion (22) and a middle portion located radially inward from the end portion (22). The end portion (22) has an outer retaining protrusion (25) formed therein, the outer retaining protrusion protruding into the pocket and configured to contact the roller to restrict radially outer movement of the roller. The end portion (22) of the cage bar (21) has an oil groove (31) in an inner peripheral surface (26) thereof, the oil groove extending in the circumferential direction and connecting to the outer retaining protrusion (25).