A hydrodynamic bearing structure is provided. The hydrodynamic bearing structure includes a bearing body, a shaft hole, at least one oil guide groove assembly, at least one air escape unit, and a recess. The shaft hole is formed in the bearing body and penetrates through the bearing body to two ends of the bearing body. The oil guide groove assembly is formed on an inner wall of the shaft hole. The air escape unit is disposed on an outer wall of the bearing body, and has a groove or a tangent plane. The recess is formed at one of the two ends (e.g., a bottom end or a top end) of the bearing body. The recess is spatially communicated with the air escape unit so that an exhaust passage is formed between an axis of the bearing structure and the air escape unit.

Oil grooves (40) formed in at least one of surfaces of a ring-shaped member (30) each have a longitudinal direction that forms an angle falling within a range of from 40 degrees to 75 degrees with respect to a radial direction of the ring-shaped member, and are arranged at equal intervals in a circumferential direction of the ring-shaped member (30). The oil grooves (40) include communicating oil grooves (40A) and non-communicating oil grooves (40B) formed to extend to the vicinity of an outer peripheral end (34), and are arranged with periodic regularity in the circumferential direction of the ring-shaped member (30). In addition, a communicating oil groove area ratio expressed by Expression: “S1/(S1+S2)” falls within a range of from 0.15 to 0.85, where S1 represents a sum of plane areas of the communicating oil grooves (40A), S2 represents a sum of the non-communicating oil grooves (40B).

An improved arrangement and method for preventing bearing ring creep is disclosed herein. The method includes providing a bearing ring including a radial surface having at least one spiral groove. The at least one groove has edge breaks connecting lateral sides to the radial surface of the bearing ring. The method includes arranging the bearing ring inside of a housing or around a shaft such that the radial surface of the bearing ring is arranged adjacent to an inner surface of the housing or an outer surface of the shaft. The edge breaks of the bearing ring frictionally engage with the shaft or the housing to prevent creep of the bearing ring.

Systems and methods for a sun gear, counter bearing parts, and bearing arrangements. The gear comprising a helical toothing and a first and a second thrust surface which are configured to axially support the sun gear at a first and a second counter thrust surface, respectively, wherein the first and the second thrust surface have a thrust generating geometry that is configured to build up a lubrication fluid film between the first thrust surface and the first counter thrust surface and between the second thrust surface and the second counter thrust surface during rotation of the sun gear. The counter bearing part for axially supporting a sun gear, and to a bearing arrangement for axially supporting a sun gear.

A resin sliding bearing includes: a bearing surface for slidingly bearing a shaft; and a hollow that communicates with the bearing surface through to a different surface of the bearing.

Oil grooves (40) formed in at least one of surfaces of a ring-shaped member (30) each have a longitudinal direction that forms an angle falling within a range of from 40 degrees to 75 degrees with respect to a radial direction of the ring-shaped member, and are arranged at equal intervals in a circumferential direction of the ring-shaped member (30). The oil grooves (40) include communicating oil grooves (40A) and non-communicating oil grooves (40B) formed to extend to the vicinity of an outer peripheral end (34), and are arranged with periodic regularity in the circumferential direction of the ring-shaped member (30). In addition, a communicating oil groove area ratio expressed by Expression: “S1/(S1+S2)” falls within a range of from 0.15 to 0.85, where S1 represents a sum of plane areas of the communicating oil grooves (40A), S2 represents a sum of the non-communicating oil grooves (40B).

A profiled rolling apparatus for lowering rolling resistance in track-guided, load-bearing movement applications. The rolling body, as part of a track roller, cam follower, caster wheel, or the like, has a radial groove (e.g. a V-shape with some internal angle) on which a non-linear profile is implemented. Profiles for various embodiments may be, but are not limited to, circular arcs, polynomials or other mathematical functions, or made up of multiple shorter linear and/or arc segments, creating a convex or concave contour on either side of the groove. Such crowning profiles may additionally or alternatively be implemented on the guiding track.

A slide bearing in the present invention is formed in a cylindrical shape and has an inner peripheral surface sliding along an axis, the slide bearing includes: a first groove in which the extension direction is a direction having a component in a circumferential direction on the inner peripheral surface; and at least two second grooves that are branched from the first groove and in which the extension directions are directions each having a component in an axial direction at least within a predetermined range from the first groove. Within a predetermined range from an end opposite to the first groove of the second groove, the width or the depth gradually decreases toward the end.

A throttle unit is equipped with a grooved block including at least one minute groove formed on a plane surface, and an opposite block having a plane surface which is opposite to the minute groove. The grooved block and the opposite block are detachably joined so as to be opposite to each other. A throttle fluid path is formed by the minute groove and the plane surface of the opposite block. At least one surface of each of the minute groove is constituted by a curved surface or an inclined surface that is inclined with respect to the plane surface of the grooved block.

Bearing assemblies that include a plurality of polycrystalline diamond (“PCD”) bearing elements, bearing apparatuses including such bearing assemblies, and methods of operating and fabricating such bearing assemblies and apparatuses are disclosed. In an embodiment, the plurality of PCD bearing elements of one or more of the bearing assemblies disclosed herein include at least one first PCD bearing element. At least a portion of the first PCD bearing element exhibits a coercivity of about 125 Oersteds or more and a specific magnetic saturation of about 14 Gauss.Math.cm3/gram or less. The first PCD bearing element includes a bearing surface with at least one groove formed therein. In an embodiment, the plurality of PCD bearing elements also include at least one second PCD bearing element. The second PCD bearing element exhibits a coercivity that is less than and a specific magnetic saturation that is greater than the first PCD bearing element.