Abstract: Provided is a boot mounting method for a constant velocity universal joint in which a boot end portion is mounted and fixed to a mating member made of metal. After the boot end portion is fitted over a receiving surface being a radially outer surface of the mating member, a high-frequency induction heating coil having a ring shape is fitted over the boot end portion. Only a top portion of the receiving surface of the mating member is heated by high-frequency induction through application of a high-frequency current to the high-frequency induction heating coil. With this action, a mounting surface being a radially inner surface of the boot end portion and the receiving surface being the radially outer surface of the mating member are integrally joined to each other.

Abstract: The invention provides a grease composition for constant velocity joints, which contains (a) a base oil, (b) a diurea thickener, (c) benzotriazole and/or a derivative thereof, and (d) a phosphate and/or an amine salt thereof; and a constant velocity joint where the grease composition is packed.

Abstract: A fixed type constant velocity universal joint includes an outer joint member having eight curved track grooves, an inner joint member having eight curved track grooves, eight torque transmission balls, and a cage configured to hold the torque transmission balls in pockets. A curvature center of each of the track grooves of the outer joint member and a curvature center of each of the track grooves of the inner joint member are offset from a joint center by an equal distance to opposite sides in the axial direction. The joint has grease sealed therein. Initial pocket gaps between the pockets and the balls each have a positive value. The grease has an initial consistency equivalent to consistency number 1 or 2, and a mixture stability of from 390 to 440.

Abstract: Provided is a boot mounting method for a constant velocity universal joint in which a boot end portion is mounted and fixed to a mating member made of metal. After the boot end portion is fitted over a receiving surface being a radially outer surface of the mating member, a high-frequency induction heating coil having a ring shape is fitted over the boot end portion. Only a top portion of the receiving surface of the mating member is heated by high-frequency induction through application of a high-frequency current to the high-frequency induction heating coil. With this action, a mounting surface being a radially inner surface of the boot end portion and the receiving surface being the radially outer surface of the mating member are integrally joined to each other.

Abstract: Provided is a fixed type constant velocity universal joint, including: an outer joint member having eight curved track grooves; an inner joint member having eight curved track grooves; eight torque transmission balls arranged; and a cage configured to hold the torque transmission balls in pockets. A curvature center of each of the track grooves of the outer joint member and a curvature center of each of the track grooves of the inner joint member are offset from a joint center by an equal distance to opposite sides in the axial direction. The joint has grease sealed therein. Initial pocket gaps between the pockets and the balls each have a positive value. The grease has an initial consistency equivalent to consistency number 1 or 2, and a mixture stability of from 390 to 440.

Abstract: The invention provides a grease composition for constant velocity joints, which contains (a) a base oil, (b) a diurea thickener, (c) benzotriazole and/or a derivative thereof, and (d) a phosphate and/or an amine salt thereof; and a constant velocity joint where the grease composition is packed.

Abstract: A lubricant composition capable of effectively preventing a rolling surface of a bearing from flaking owing to hydrogen embrittlement. The bearing is lubricated with the lubricant composition. The lubricant composition is lubricating oil or grease. The lubricant composition contains a molybdate. The lubricant composition also contains an organic acid salt. At least one molybdate is selected from sodium molybdate, potassium molybdate, and lithium molybdate. The organic acid salt is a sodium salt of an organic acid having one to 20 carbon atoms. 0.01 to 5 wt % of the molybdate is added to the entirety of the lubricant composition. 5 wt % to 70 wt % of the organic acid salt is added to the addition amount of the molybdate. The lubricant composition forms a film containing a molybdenum compound in addition to an iron oxide film on a worn surface of the bearing.

Abstract: There is provided a constant velocity universal joint having excellent durability at high temperature while using a boot made of silicone rubber that does not include cerium oxide or other rare earth element-containing compound. The constant velocity universal joint is provided with an outer joint member (2), an inner joint member (4), a shaft (8) coupled to the inner joint member (4), and a boot (9) mounted directly or via another member to the outer joint member (2) and the shaft (8), the boot (9) being a molded article of a silicone rubber composition including silicone rubber, iron oxide, and titanium oxide and not including a rare earth element-containing compound. The silicone rubber composition furthermore includes barium zirconate as required.

Abstract: A constant-velocity universal joint includes an outer joint member; an inner joint member arranged in an inside of the outer joint member; and torque transmitting members. At least one of the outer joint member and the inner joint member comprises track grooves that are engaged with rolling surfaces of the torque transmitting members. At least one of the components of the constant-velocity universal joint is formed of a metal sintered compact. The metal sintered compact has a relative density of 80% or more and less than 100%. The metal sintered compact comprises a hardened layer formed on a surface thereof through heat treatment. Among the components each formed of the metal sintered compact, a component having a ring shape is subjected to a cold rolling process.

Abstract: There is provided a constant velocity universal joint having excellent durability at high temperature while using a boot made of silicone rubber that does not include cerium oxide or other rare earth element-containing compound. The constant velocity universal joint is provided with an outer joint member (2), an inner joint member (4), a shaft (8) coupled to the inner joint member (4), and a boot (9) mounted directly or via another member to the outer joint member (2) and the shaft (8), the boot (9) being a molded article of a silicone rubber composition including silicone rubber, iron oxide, and titanium oxide and not including a rare earth element-containing compound. The silicone rubber composition furthermore includes barium zirconate as required.

Abstract: A fixed type constant velocity universal joint comprises a ball and a lubricating grease sealed therein. A surface roughness of the ball is set to Ra 0.15 ?m or less and a surface roughness of a counterpart surface on which the ball rolls is set to be higher than the surface roughness of the ball. An additive composition of the lubricating grease comprises a base oil, a diurea compound, molybdenum dithiocarbamate, zinc dialkyldithiophosphate, melamine cyanurate, molybdenum disulfide, and calcium salt of alkylaromatic sulfonic acid.

Abstract: A constant-velocity universal joint includes an outer joint member; an inner joint member arranged in an inside of the outer joint member; and torque transmitting members. At least one of the outer joint member and the inner joint member comprises track grooves that are engaged with rolling surfaces of the torque transmitting members. At least one of the components of the constant-velocity universal joint is formed of a metal sintered compact. The metal sintered compact has a relative density of 80% or more and less than 100%. The metal sintered compact comprises a hardened layer formed on a surface thereof through heat treatment. Among the components each formed of the metal sintered compact, a component having a ring shape is subjected to a cold rolling process.

Abstract: The present invention provides a lubrication system that improves the force of retaining a lubricating component of a foamed lubricant, is capable of minimizing the amount of exudation of the lubricating component which occurs owing to deformation of the foamed lubricant, is capable of compensating for a lubricating function even when the lubricating component exudes insufficiently from the foamed lubricant, and is capable of complying with a demand that the lubrication system has a long life and can be produced at a low cost. The lubrication system comprises a foamed lubricant containing a lubricating component in a resin thereof which foams, hardens, and becomes porous and a grease for auxiliary lubrication which is present together with the foamed lubricant in a portion to be lubricated.

Abstract: Provided is a fixed type constant velocity universal joint which can achieve, at low cost, excellent properties in terms of durability, high load condition, low load condition, and high angle condition. The fixed type constant velocity universal joint comprises a lubricating grease sealed therein. A surface roughness of a ball (37) is set to Ra 0.15 ?m or less and a surface roughness of a counterpart surface on which the ball (37) rolls is set to be higher than the surface roughness of the ball (37). An additive composition of the lubricating grease comprises a base oil, a diurea compound, molybdenum dithiocarbamate, zinc dialkyldithiophosphate, melamine cyanurate, molybdenum disulfide, and calcium salt of alkylaromatic sulfonic acid.

Abstract: A lubricating having a foam lubricant that minimizes exudation of the lubricating component caused by deformation of the foam lubricant, is excellent in initial lubrication, has a long life, has a low cost, and is excellent in the productivity thereof; a bearing utilizing the lubricating system; a universal joint utilizing the lubricating system; and a process for the production thereof. A lubricating system includes a foam lubricant (9) containing a lubricating component in a resin thereof which foams, hardens, and becomes porous and a lubricant (10) for initial lubrication which is present together with the foam lubricant (9) in a portion to be lubricated. The lubricant (10) for initial lubrication consists of grease having a worked penetration not less than 300 or having a degree of oil separation not less than 0.7 wt % when the grease is left 24 hours at 70° C.

Abstract: A lubricant composition capable of effectively preventing a rolling surface of a bearing from flaking owing to hydrogen embrittlement. The bearing is lubricated with the lubricant composition. The lubricant composition is lubricating oil or grease. The lubricant composition contains a molybdate. The lubricant composition also contains an organic acid salt. At least one molybdate is selected from sodium molybdate, potassium molybdate, and lithium molybdate. The organic acid salt is a sodium salt of an organic acid having one to 20 carbon atoms. 0.01 to 5 wt % of the molybdate is added to the entirety of the lubricant composition. 5 wt % to 70 wt % of the organic acid salt is added to the addition amount of the molybdate. The lubricant composition forms a film containing a molybdenum compound in addition to an iron oxide film on a worn surface of the bearing.

Abstract: A lubricant composition capable of preventing a rolling surface of a bearing from flaking owing to hydrogen embrittlement. The bearing is lubricated with the lubricant composition which is a lubricating oil or grease. The lubricant composition contains a molybdate and an organic acid salt. At least one molybdate is selected from sodium molybdate, potassium molybdate, and lithium molybdate. The organic acid salt is a sodium salt of an organic acid having one to 20 carbon atoms. The lubricant composition forms a film containing a molybdenum compound in addition to an iron oxide film on a worn surface of the bearing or on a fresh surface of an iron-based metal generated by wear. The bearing is used as a rolling bearing for use in electric parts and auxiliary machines of a vehicle. The bearing is also used as a bearing, for a motor, in which the lubricant composition is sealed.

Abstract: The present invention provides a lubrication system that improves the force of retaining a lubricating component of a foamed lubricant, is capable of minimizing the amount of exudation of the lubricating component which occurs owing to deformation of the foamed lubricant, is capable of compensating for a lubricating function even when the lubricating component exudes insufficiently from the foamed lubricant, and is capable of complying with a demand that the lubrication system has a long life and can be produced at a low cost. The lubrication system comprises a foamed lubricant containing a lubricating component in a resin thereof which foams, hardens, and becomes porous and a grease for auxiliary lubrication which is present together with the foamed lubricant in a portion to be lubricated.

Abstract: It is an object of the present invention to provide a lubricating system that improves the force of retaining a lubricating component of a foam lubricant, minimizes an exudation amount of the lubricating component caused by deformation of the foam lubricant, is excellent in initial lubrication, has a long life, has a low cost, and is excellent in the productivity thereof; a bearing utilizing the lubricating system; a universal joint utilizing the lubricating system; and a process for the production thereof. A lubricating system includes a foam lubricant (9) containing a lubricating component in a resin thereof which foams, hardens, and becomes porous and a lubricant (10) for initial lubrication which is present together with the foam lubricant (9) in a portion to be lubricated. The lubricant (10) for initial lubrication consists of grease having a worked penetration not less than 300 or having a degree of oil separation not less than 0.7 wt % when the grease is left 24 hours at 70° C.

Abstract: A porous solid lubricant includes a lubricating component, and a resin component. The lubricating component is a solid material made porous by foaming, and is occluded in the resin. A bearing or a constant-velocity joint has the above porous solid lubricant sealed therein. Since the lubricating component is occluded in the resin while foaming the resin component, the lubricating component can be slowly exuded through molecules of the resin due to deformation of the flexible resin under external force such as compression, expansion, bending and twisting. The amount of lubricating oil retained is larger than the amount of oil retained in pores by mere impregnation. Thus, such a bearing which has a long life, can be operated at a high speed, and can be manufactured at a low cost. Also, such a constant-velocity joint has a long life and has a rubber boot less likely to be damaged.