Abstract: The object of the present invention is to improve sealing performance of a seal under a specific environment. The seal is arranged in an annular space A in which a rotary shaft 1 and a housing 2 face each other, and partitions the annular space in axial direction into a vacuum space B and an atmospheric pressure space C. The seal is constituted such that a main lip 6 of the seal has an axial contact width W0 with which the main lip slides on and contacts with the rotary shaft 1 and which is set to be equal to or larger than an axial contact width W1 necessary to secure minimum sealing performance with respect to a sealed portion and equal to or smaller than an axial contact width W2 with which sliding resistance against the rotary shaft becomes a permissible upper limit, to thereby prevent the axial contact width W0 from influencing rotation characteristics with respect to the rotary member and to allow securing required sealing performance.

Abstract: A rolling bearing is used for supporting a rocking mechanism or a rotating mechanism, and a film comprising a fluorine-containing polymer having a functional group(s) under a fluidizied state or a film comprising a fluorine-containing polyurethane compound under a solid state is formed on at least the track surface of the rolling bearing. Since this film does not contain ions for uniformly dispersing a thickner having non uniform particle sizes such as fluorine based grease of the prior art, breakage of the film between a rolling element and a race is not likely to occur, and wear of a rolling element race resulting from the direct contact between them due to breakage of the film can be reduced. When this film is tha same kind of a film as a protective film of the surface of an information recording disk, dust generating components of the film are the same kind of components as those of the protective film, and information recording/reproduction of the information recording disk is not impeded.

Abstract: A process for forming a lubricating film on a direct acting bearing includes the steps of forming a liquid film on at least the rolling and sliding portions of the direct acting bearing by using a solution prepared by diluting a fluorine-containing polymer in a solvent. The liquid film is then cured to form a solid film of a fluorine-containing polyurethane high molecular compound on the direct acting bearing.

Abstract: There is provided a rolling bearing which is capable of reducing vibrations and noise while satisfying requirements of high-speed rotation and prolonged life of grease. Balls are formed of a ceramic material whose major component is zirconia and which has a Young's modulus of 250 GPa or lower. The zirconia content of the ceramic material is not less than 80 wt %. The ceramic material is sintered by HIP. The balls are low in Young's modulus, allowing the contact surface pressure between rolling element and raceway to be lowered, so that the bearing can be reduced in vibrations and noise. Also, the bearing is high in durability because of HIP sintering.

Abstract: A direct-acting bearing comprising a rail in the form of a shaft, a movable body fitted slidably to it, and a plurality of rolling bodies disposed between the rail and the movable body so as to roll and circulate with the relative sliding motions thereof, characterized in that a solid film of a fluorine-containing polyurethane high molecular compound is formed on at least the rolling and sliding portions of its components.

Abstract: A feed screw including a screw shaft, a nut meshed with the screw shaft and a plurality of rolling members inserted between the screw shaft and the nut, wherein a solid film of a fluorine-containing polyurethane polymer is formed on any portions in rolling/sliding contact. The molecules of this solid film have urethane bonds, and form a three-dimensional reticular structure. Therefore, the film is unlikely to separate, peel off or wear. Accordingly, the feed screw produces less dust, improves lubricating property and thus elongates its life.

Abstract: There is provided a method for manufacturing a bearing, which has increased adhesive strength of lubricant to surfaces of rolling elements, a surface of a raceway or a surface of a cage. A surface of a ball, a raceway surface of an inner ring and a raceway surface of an outer ring are subjected to fluoride coating substitution process or ion bombardment process so that their oxygen concentration becomes not more than 2 ppm/mm.sup.2, by which surface oxide is removed. After the removal of the oxide, the surfaces are coated with a solid lubricant of silver, lead or the like. The surfaces from which oxide has been removed have good lubricant adhesion, making breaks in the lubricant unlikely to occur. Thus, the life of the bearing is prolonged.

Abstract: A solid film of a fluorine-containing polyurethane polymer is formed on at least one of the constituent elements (inner and outer rings, rolling member and retainer) of a rolling-contact bearing. The molecules of the solid film of the fluorine-containing polyurethane polymer have urethane bonds, and form a three-dimensional reticular structure. Therefore, the film is unlikely to separate, peel off or wear. The occurrence of the dust can be restricted, and lubrication property can be improved.

Abstract: A rolling bearing in which rolling elements, alternatively, the rolling elements and a pair of races are made of a ceramic material prepared by sintering a sintering material of silicon nitride containing an MgAl.sub.2 O.sub.4 of spinel structure and at least silicon oxide selected between silicon oxide and silicon carbide, as a sintering assistant.Such a rolling bearing is excellent in heat resistance and wearing resistant, and presents superior corrosive resistance when it is used in a corrosive atmosphere, thus having a long service life.

Abstract: The outer surface of a rolling element (3) of a rolling bearing is coated with a lubricating film (4) having three layers (5, 6, 7). The bottommost layer (5) coated on the surface of the rolling element (3) is made of Sn; the intermediate layer (6) coated on the surface of the bottommost layer (5) is made of Ag; and the topmost layer (7) coated on the surface of the intermediate layer (6) is made of Pb. As a result of this construction, Ag serves as a binder between the Pb-Sn alloy and steel constituting an inner race member (1), an outer race member (2) and/or the rolling element (3), which in turn renders the lubricating film (4) wettable with respect to the surfaces of the inner and outer race members (1, 2) defining a race and the outer surface of the rolling element (3). Hence, stable lubrication between the bearing components can be implemented.

Abstract: In a method of lubrication between two sliding members at least one of which is made of a ceramic material, the improvement according to the present invention is characterized in that soot as produced by burning a hydrocarbon fuel is supplied between the two sliding members.

Abstract: A full type ball bearing for turbochargers comprising an inner ring and an outer ring both made of steel and balls made of a ceramic.

Abstract: A rolling bearing suitable for use in a high temperature atmosphere is provided.The bearing is partly or entirely made of a ceramic material with at least its inner ring being made of a ceramic material so as to improve the rotational and antiabrasive efficiencies thereof in a high temperature operating condition.Further, in order to prevent both chamfered ends of the inner ring from cracking or chipping, the inner peripheral surface is crowned to have a Lundberg profile thereby avoiding a local concentration of stress on the inner ring.

Abstract: A heat-resistant ball bearing comprising inner and outer races made of a heat-resistant steel, a plurality of balls made of a ceramic, and a crown retainer made of graphite. Preferably, the retainer has a crown shape and comprises a plurality of projections forming a pocket and a cut-away portion connected to the pocket. The width of the cut-away portion is selected to be about 97 to 99% of the diameter of the ball.

Abstract: A traction drive spindle device includes an input shaft connectable to a drive main shaft for rotation therewith. A hollow holder shaft is connected to an output end of the input shaft in coaxial relation thereto, the hollow holder shaft having a plurality of planetary rollers mounted thereon intermediate opposite ends of the holder shaft. A high-speed spindle is rotatably received in a bore of the hollow holder shaft, the high-speed spindle having an inner end portion which is received in the bore and serves as a sun shaft disposed in rolling contact with the planetary rollers. A housing is mounted on the outer periphery of the holder shaft through a first ball-and-roller bearing so as to be rotatable relative to the holder shaft, the housing having a fixed ring fixed to an inner periphery thereof. The planetary rollers are disposed in rolling contact with the fixed ring. A second ball-and-roller bearing is interposed between the holder shaft and the high-speed spindle.

Abstract: A structure of attaching to a metal shaft a ceramics bearing which comprises an inner ring, an outer ring and rolling members and in which at least the inner ring is made of ceramics. The inner ring is made of silicon nitride or sialon molded by the hot press sintering process or the hot isostatic press sintering process. The shaft is press-fitted in the inner ring with an interference of not greater than a specified value.

Abstract: Cracking of a ceramic bearing fitted over a metal shaft is prevented by grooves on an inner periphery of a ceramic inner race and/or on an outer periphery of the metal shaft.

Abstract: A ceramics bearing comprising an inner ring, and outer ring, and a plurality of rolling elements rollably arranged between the inner and outer rings which is characterized in that the fracture toughness factors K.sub.IC (MPam1/2) of the inner and the outer rings are identical and that of the rolling elements is greater than that of the inner and the outer rings by about 0.5-2.0.

Abstract: A rotating member supporting apparatus has a rotating shaft which is inserted to a bore formed in a support member. A rolling bearing is interposed between the rotating shaft and support member and rotatably supports the rotating shaft. The bearing includes an inner and outer rings which have resistance to heat and corrosion, and a plurality of rolling elements rollably arranged between the inner and outer rings. The rolling elements are formed of ceramic material.