A ball spline with detour tracks includes spline shaft, nut part movable along a longitudinal direction of the spline shaft, and balls between the nut part and the spline shaft, wherein the nut part includes nut adapted to insert the spline shaft thereinto and retainers on longitudinal sides of the nut, the spline shaft includes tracks extended along the longitudinal direction, the nut includes load track grooves formed in longitudinal direction on inner peripheral surface into which the spline shaft is inserted and non-load circulating portions formed in the longitudinal direction, each retainer includes circulating grooves on the inner peripheral surface to face the load track groove and non-load circulating portion, the balls run between the tracks and the load track grooves, and each track includes track groove formed in longitudinal direction of the spline shaft and detour tracks whose longitudinal sides are connected to the track groove.

A bearing includes a ring unit including an outer ring and an inner ring. The inner ring is surrounded by the outer ring and shares a common axis. The outer ring includes at least one first recess, and the inner ring includes at least one second recess. Each of the at least one first recess and the at least one second recess is filled with a first durable material elements by way of welding. At least one roller unit including multiple rollers which rolls between the inner and outer rings. The rollers contact the multiple first durable material elements. The hardness of the multiple first durable material elements and the hardness of the rollers are higher than that of the ring unit so as to increase the life of use of the bearing and reduce manufacturing cost.

A bearing includes a ring unit including an outer ring and an inner ring. The inner ring is surrounded by the outer ring and shares a common axis. The outer ring includes at least one first recess, and the inner ring includes at least one second recess. Each of the at least one first recess and the at least one second recess is filled with a first durable material elements by way of welding. At least one roller unit including multiple rollers which rolls between the inner and outer rings. The rollers contact the multiple first durable material elements. The hardness of the multiple first durable material elements and the hardness of the rollers are higher than that of the ring unit so as to increase the life of use of the bearing and reduce manufacturing cost.

A bearing assembly includes a roller bearing unit, an inner race and an outer race. The roller bearing unit is formed of polycrystalline super-hard material having a mean mass density of at most 4.5 g/cm.sup.3 and a volume-weighted arithmetic mean thermal conductivity of at least 100 W/m.Math.K.

A ball bearing assembly device includes: an inner and outer ring holding unit which holds an outer ring and inner ring in a state where an outer ring raceway surface and inner ring raceway surface are eccentric to each other on a same plane so as to form a gap space; a stocker; a robot arm; a ball holding mechanism which is disposed at a tip of the robot arm; and a control unit. The control unit controls the ball holding mechanism to hold any ball from the stocker, controls the robot art to transport the held ball to a ball insertion position in the gap space corresponding to a kind of ball bearing, and inserts the held ball into the gap space, which are repeated by the number of balls of the ball bearing.

A ball bearing assembly device includes: an inner and outer ring holding unit which holds an outer ring and inner ring in a state where an outer ring raceway surface and inner ring raceway surface are eccentric to each other on a same plane so as to form a gap space; a stocker; a robot arm; a ball holding mechanism which is disposed at a tip of the robot arm; and a control unit. The control unit controls the ball holding mechanism to hold any ball from the stocker, controls the robot art to transport the held ball to a ball insertion position in the gap space corresponding to a kind of ball bearing, and inserts the held ball into the gap space, which are repeated by the number of balls of the ball bearing.

A method is provided that forms a solid film on a bearing component of a rolling bearing. A solution containing a fluorine compound and a lubricant having no functional group is allowed to adhere to the bearing component as a liquid film, the fluorine compound containing 3-(trimethoxysilyl) propyl methacrylate, hexafluoropropene, and methyl methacrylate as components. The solid film is formed on the at least one of the bearing components by hardening the adhering liquid film.

A steel alloy for a bearing, the alloy having a composition that provides: from 0.8 to 1.0 wt. % carbon, from 0.1 to 0.5 wt. % silicon, from 0.2 to 0.9 wt. % manganese, from 2.0 to 3.3 wt. % chromium, from 0 to 0.4 wt. % molybdenum, from 0 to 0.2 wt. % cobalt, from 0 to 0.2 wt. % iridium, from 0 to 0.2 wt. % rhenium, from 0 to 0.2 wt. % vanadium, from 0 to 0.1 wt. % niobium, from 0 to 0.5 wt. % tungsten, from 0 to 0.2 wt. % nickel, from 0 to 0.4 wt. % copper, from 0 to 0.05 wt. % aluminum, from 0 to 150 ppm nitrogen, and the balance iron, together with any unavoidable impurities.

Inventive manufacture of CrB.sub.2—Al.sub.2O.sub.3 composites is based on pressureless sintering. According to typical inventive practice, CrB.sub.2 powder and Al.sub.2O.sub.3 powder are mixed together in selected volumetric proportions so that the volume of the CrB.sub.2 does not exceed 50% of the overall volume of the CrB.sub.2—Al.sub.2O.sub.3 mixture. The CrB.sub.2—Al.sub.2O.sub.3 mixture is shaped into a green body. The green body is pressureless sintered in a non-oxidizing atmosphere at a firing temperature in the approximate range between 1600° C. and 2050° C. The present invention succeeds in preparing, via pressureless sintering, a proportionality-associated range of compositions in the CrB.sub.2—Al.sub.2O.sub.3 system, which is a potentially “advanced” ceramic system. A typical inventively fabricated CrB.sub.2—Al.sub.2O.sub.3 composite is inventively configured in a complex shape, and has “advanced” material (e.g., mechanical) properties that are favorable for a contemplated application. Inventive manufacture of ceramic-ceramic composites is thus dually attributed, and uncommonly so, with complex shape-ability and advanced capability.

Bearing component providing unaffected material that has a surface, which has been subjected to a hard machining process during where the temperature of the surface did not exceed the austenitizing temperature of the unaffected material. The surface of the bearing component includes a white layer formed during the hard machining process. The white layer has a nano-crystalline microstructure that includes grains having a maximum grain size up to 500 nm. The white layer is located directly adjacent to the unaffected material of the bearing component, where no dark layer is formed during the hard machining process.