Force coupling or torque coupling assemblies, apparatuses, systems, and methods include assemblies that each include superhard contact elements. At least some of the superhard contact elements may be configured to remain in contact with each other when a rotational force and/or a thrust force is applied between the assemblies.

A rolling bearing includes an outer ring, an inner ring, a plurality of rolling bodies, and a seal member. An outer peripheral portion of the seal member is fixed by a retaining ring to a groove portion formed on an inner peripheral surface of the outer ring and an inner peripheral portion of the seal member is elastically deformable. The seal member includes an inclined portion. The seal member satisfies 0.25≤Skn/Skt≤2.5 when Skn is a radial length from an inclination start part of the inclined portion on an inside in an axial direction to an outermost diameter position of a part of contact of the seal member with an outer peripheral surface of the inner ring and Skt is a thickness of the inclined portion in a direction perpendicular to an inclination direction.

Systems and methods are described for a reciprocating mechanism. The system includes at least one axially translating y-axis component configured to reciprocate substantially along a y-axis with a reciprocating motion of a piston assembly relative to a base. The system also includes at least one x-axis component slidingly coupled via at least one bearing assembly to and translating with the at least one y-axis component along the y-axis. The at least one x-axis component is configured to reciprocate substantially perpendicularly to the y-axis relative to the at least one y-axis component, and includes an orbital output component and an orbital linking component disposed substantially concentric with the orbital output component. The system also includes a stationary output component rotatably attached to the base in a direction that is substantially perpendicular to both the x-axis and y-axis, and a stationary linking component rotatably attached to the base in a direction that is substantially concentric with the stationary output component.

A bearing system includes a first bearing, the first bearing being annular in shape and defining a ring aperture, the first bearing including a first surface and a second surface, a second bearing being substantially the same in construction to the first bearing, a first surface of the second bearing contacting a second surface of the first bearing, wherein each of the bearings is constructed of nylon MDS.

A tapered roller bearing includes an inner ring having a tapered raceway surface and a large-collar surface on a large-diameter side of the raceway surface, and tapered rollers. Each of the rollers has a large end surface guided by the large-collar surface. When R represents a set curvature radius of the large end surface and R.sub.BASE represents a base curvature radius from a vertex of a cone angle of each of the tapered rollers to the large-collar surface, the base curvature radius R.sub.BASE is 100 mm or less, and a ratio R/R.sub.BASE of the set curvature radius R to the base curvature radius R.sub.BASE is set to 0.90 or less. When R.sub.ACTUAL represents an actual curvature radius of the large end surface of each of the tapered rollers, a ratio R.sub.ACTUAL/R of the actual curvature radius R.sub.ACTUAL to the set curvature radius R exceeds 0.5.

An example bushing of a hydraulic hammer tool includes a bulk region and an inner region. The inner region has a relatively greater hardness than the bulk region. The inner region may also be compressively stressed, while the bulk region may have tensile stress. The stress and/or hardness profile of the bushing may enhance its resistance to wear and galling defects when a hammer of the hydraulic hammer tool is held in alignment by the bushing. The bulk region of the bushing may be relatively soft, resulting in the bushing having a relatively high level of toughness. The bushing may be formed using medium to high carbon steel by rough forming the bushing, hardening the bushing, tempering the bushing, induction hardening the inner region of the bushing, and then quenching the inner region.

A sliding element, such as a bearing, and a method of manufacturing the sliding element, is provided. The sliding element is formed of an aluminum alloy material which includes zinc in an amount of 5 wt. % to 83 wt. %. The sliding element may also include silicon and/or magnesium. The sliding element is typically formed by casting, heat treating at a temperature of 400° C. to 577° C., and cooling at a rate of less than 50° C. per hour to a temperature ranging from 400° C. to 200° C. The aluminum alloy material is then heat treated at a temperature of 100° to 275° C. for at least 5 hours to form a soft phase consisting essentially of the zinc. The second heat treatment, or possibly both heat treatments, may not be required when the aluminum alloy material includes the magnesium.

A constant velocity universal joint includes an inner ring and an outer ring. A cage is disposed between an outer spherical surface of the inner ring and an inner spherical surface of the outer ring, and has windows in which respective balls are received. The cage has ball contact surface areas with which the balls come into contact, and includes soft portions that are lower in hardness than the ball contact surface areas. The soft portions are formed by local heat treatment at portions of the windows that are kept out of contact with the balls or surface portions around the windows.

A Plain bearing having an outer ring and an inner ring, the outer ring and the inner ring providing respectively an inner surface and an outer surface intended to cooperate with each other for the relative movement of the outer and inner rings, the inner surface of the outer ring and the outer surface of the inner ring each including a coating including at least one layer. The hardness of the coating on the inner surface of the outer ring is less than the hardness of the outer ring, and the hardness of the coating on the outer surface of the inner ring is greater than the hardness of the inner ring.

A speed reducer includes a reduction mechanism, which includes an internal gear and an external gear meshing with the internal gear, and a first member, and transmits rotating motion decelerated by the reduction mechanism to a driven member. The speed reducer includes a protection member disposed between the first member and the driven member. The first member is formed of a material having specific gravity lower than at least one of the internal gear and the external gear and hardness lower than the driven member. The protection member is formed of a material having hardness higher than the first member.