JP2008014374A - Constant-velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent vibration propagated to an outside joint member of a constant-velocity universal joint at low cost. <P>SOLUTION: A damping material 10 composed of a porous solid lubricating agent is sealed into a region where an axial position of a space is regulated by a pocket 5a of a cage 5 in the space which surrounds a ball 4, that is, the space formed of a track groove 1a formed on the spherical internal face of an outer ring 1 and a track groove 3a formed on the spherical external face of an inner ring 3. The porous solid lubricating agent constituting the damping material 10 has a lubricating component containing a lubricating oil and a resin component as essential components, is a solid substance formed of the resin component which is foamed and made porous, and is formed by occluding the lubricating component into resin. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a constant velocity universal joint that is used in a drive shaft of an automobile and various industrial machines to transmit rotational torque.

  In recent years, technological improvements for higher performance, compactness, and weight reduction of automobiles and industrial machines have progressed, and constant velocity universal joints used for drive transmission of automobile parts and industrial machines have also been reduced in size, weight, and performance. There is a growing demand for (long life) and long life.

  That is, the constant velocity universal joint is applied in a direction in which a high load is applied by reducing the size and weight in the same manner as the entire machine, and it may be difficult to achieve a long life with lubrication with conventional grease. Therefore, there is a demand for a constant velocity universal joint that has a long life and excellent maintainability even under severe conditions such as high temperature and high load.

  Here, in general, lubricants are used in sliding parts and rotating parts of machines such as automobiles and industrial machines, and grease or liquids that have been provided with shape retention by increasing the lubricating oil. There are known solid lubricants that can hold the lubricant and prevent its scattering and dripping.

  For example, solid lubricants that are mixed with lubricating oil or grease with ultra-high molecular weight polyolefin, or urethane resin and its curing agent, and have a physical property that gradually exudes by holding a liquid lubricating component between the resin molecules. Is known (see Patent Documents 1, 2, and 3).

  Also known is a polyurethane elastomer having self-lubricating properties by reacting a polyol, which is a polyurethane raw material, with a diisocyanate in a lubricating component in the presence of a lubricant (see Patent Document 4).

  Such a solid lubricant, for example, gradually precipitates the lubricating oil when it is sealed in a bearing and solidified. If this is used, maintenance for replenishing the lubricating oil becomes unnecessary, and there is a lot of moisture. It is often useful for extending the life of bearings even in environments where they are used or in environments where strong inertial forces are applied.

  However, if such a solid lubricant is used in a portion where expansion (sliding) or bending, such as a drive part of a constant velocity universal joint, is repeatedly applied at a high frequency, it follows the expansion (sliding) or bending. A very large force is required for the deformation, or a very large stress is applied to the solid lubricant, and a mechanical strength is also required for a portion holding the solid lubricant.

  However, since the strength and filling rate of the solid lubricant are usually compensatory, it is difficult to keep the lubricant at a high filling rate, which may hinder the extension of the service life.

  Therefore, there is a demand for a solid lubricant that can be applied to a constant velocity universal joint in which expansion (sliding), bending, and the like repeatedly occur.

By the way, as the solid lubricant, there is an oil-impregnated solid lubricant in which a soft resin foamed to form continuous air holes is impregnated with lubricating oil, and the lubricating oil is retained in the pores. It is known to fill and use the entire interior of the constant velocity universal joint (see Patent Document 5).
JP-A-6-41569 JP-A-6-172770 JP 2000-319681 A Japanese Patent Laid-Open No. 11-286601 JP-A-9-42297

  However, the oil-impregnated solid lubricant according to the above-described conventional technology can follow deformation due to expansion and contraction (sliding) and bending of the constant velocity universal joint if it has flexible deformability according to external force, When the force is small and it is used under high-speed rotation conditions, there is a possibility that the lubricant will be exhausted due to rapid precipitation.

  Oil-containing solid lubricants can be used in areas that move for a long time or when used in open spaces, the lubricant will precipitate, and this lubricant will repeatedly release and absorb from the pores and will not endure and flow in the space. To do.

  When such excessively precipitated lubricating oil comes into contact with the boot attached to the shaft and the outer joint member in the constant velocity universal joint, the component of the lubricating oil may deteriorate the boot material.

  Further, in the manufacturing process of the solid lubricant, many processes are required to surely impregnate the lubricating oil and grease, so that it is difficult to manufacture a constant velocity universal joint at a low cost.

  Therefore, the problem of the present invention is to solve the above-mentioned problems, improve the lubricating oil retention force of the solid lubricant, keep the amount of lubricating oil deposited by deformation due to external force to the minimum necessary, and use the lubricating oil efficiently. It is intended to provide a constant velocity universal joint that alleviates the vibration of the outer joint member when a rotational torque is generated, has a long life, causes little deterioration of the boot, and further simplifies the manufacturing process to help reduce the manufacturing cost.

  The constant velocity universal joint according to the present invention for solving the above-mentioned problems has an outer joint member in which a track groove is formed on the inner peripheral surface, and a track groove is formed on the outer peripheral surface arranged inside the outer joint member. An inner joint member; and a rolling element interposed between the track groove of the outer joint member and the track groove of the inner joint member, the lubricating component including the lubricating oil and the resin component as essential components, and the resin component Is a solid material foamed and made porous, and a damping material made of a porous solid lubricant in which the lubricating component is occluded inside the resin is enclosed in a space surrounding the rolling element. (Claim 1). The term “occlusion” as used in the present invention is the same as the meaning of occlusion in the scientific term, and indicates that a liquid lubricant is contained in a solid resin without becoming a compound.

  In the above constant velocity universal joint, a lubricating component including a lubricating oil and a resin component are essential components, the resin component is a solid material foamed and made porous, and the lubricating component is occluded inside the resin. A vibration damping material made of a porous solid lubricant is sealed in a space surrounding the rolling elements. As a result, the vibration damping material absorbs minute vibrations of the rolling elements generated between the track groove of the outer joint member and the track groove of the inner joint member transmitted during the transmission of the rotational torque, so that the vibration of the outer joint member is reduced. Can do. Further, the frictional resistance between the track groove of the outer joint member and the track groove of the inner joint member with which the rolling element moves and contacts can be suppressed, and torque transmission can be made smooth.

  The present invention can be applied to various constant velocity universal joints. For example, the outer peripheral surface of the outer joint member and the outer peripheral surface of the inner joint member are spherical, and there are three between the inner peripheral surface of the outer joint member and the track groove formed on the outer peripheral surface of the inner joint member. Barfield type constant velocity universal joint (BJ) which is one of fixed type constant velocity universal joints with any number of balls (rolling elements) of 5, 6, 6, 7 or 8 Applicable. The undercut-free type constant velocity universal joint is interpreted as being included in the same classification as the Barfield type constant velocity universal joint, and is described in the present invention.

  Further, according to the present invention, a plurality of linear track grooves extending in the axial direction are formed on the cylindrical inner peripheral surface of the outer joint member, and a pair of track grooves of the outer joint member is formed on the spherical outer peripheral surface of the inner joint member. A plurality of linear track grooves are formed, and any of three, four, five, six, seven, or eight is provided between the track grooves of these outer joint members and the track grooves of the inner joint members. The present invention can be applied to a double offset type constant velocity universal joint (DOJ) which is one of sliding type constant velocity universal joints in which such a number of balls (rolling elements) are interposed.

  Alternatively, a plurality of linear track grooves are formed on the inner peripheral surface of the outer joint member, and a plurality of linear track grooves that are paired with the track grooves of the outer joint member are formed on the outer peripheral surface of the inner joint member, and The track groove of the outer joint member and the track groove of the inner joint member are inclined at a predetermined angle in opposite directions with respect to the axis, and the track groove of these outer joint member and the track groove of the inner joint member Cross groove type constant velocity universal joint (LJ) which is one of sliding type constant velocity universal joints with any number of balls (rolling elements) of 4, 6, 8 or 10 at the crossing part ).

  The constant velocity universal joint according to the present invention does not enclose a porous solid lubricant as a damping material in the entire inside of the outer joint member, and is liable to cause slight vibration when rotational torque is generated in the constant velocity universal joint. Since the rolling elements and the track grooves are enclosed, the amount of the porous solid lubricant used can be kept to a minimum. As a result, it is possible to reduce the manufacturing cost of the constant velocity universal joint that realizes weight reduction, high performance, smooth torque transmission, and mitigation of vibration transmitted to the outer joint member.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1A shows an embodiment in which the present invention is applied to a barfield type constant velocity universal joint (BJ) which is one of fixed type constant velocity universal joints as a first embodiment of the present invention.

  The constant velocity universal joint includes an outer ring 1 that is an outer joint member, an inner ring 3 that is an inner joint member, a ball 4, and a cage 5. The outer ring 1 has a plurality of track grooves 1a formed on a spherical inner peripheral surface. The inner ring 3 has a plurality of track grooves 3 a that are paired with the track grooves 1 a of the outer ring 1 on the spherical outer peripheral surface, and is interposed between the track grooves 1 a of the outer ring 1 and the track grooves 3 a of the inner ring 3. Three, four, five, six, seven or eight balls 4 are interposed, and these balls 4 are pockets 5a of the cage 5 disposed between the outer ring 1 and the inner ring 3. Held in.

  A bellows-like boot 7 made of an elastomer such as rubber, resin, etc. having heat resistance, oil resistance, and wear resistance is attached from the opening end of the outer ring 1 to the shaft 6. , 9 and fixed. The boot 7 completely seals the inside of the outer ring 1.

  The outer ring 1 has a solid component in which a lubricating component including a lubricating oil and a resin component are essential components, the resin component is foamed and made porous, and the lubricating component is occluded in the resin. In the space surrounding the ball 4, that is, in the space formed by the track groove 1 a of the outer ring 1 and the track groove 3 a of the inner ring 3, the vibration damping material 10 made of a porous solid lubricant is axially positioned. Is enclosed in an area restricted by the pocket 5a of the cage 5.

  As a resin component constituting the porous solid lubricant as the vibration damping material 10, either or both of an elastomer and a plastomer can be adopted as an alloy or a copolymer component among plastics or rubber.

  In the case of rubber, various rubbers such as natural rubber, isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, butyl rubber, nitrile rubber, ethylene propylene rubber, silicone rubber, urethane elastomer, fluorine rubber, and chlorosulfone rubber can be employed.

  In the case of plastic, polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyacetal, polyamide 4,6 (PA4,6), polyamide 6,6 (PA6,6), polyamide 6T (PA6T), polyamide 9T (PA9T) General-purpose plastics and engineering plastics.

  Moreover, it is not restricted to said plastics etc., Polyurethane foams, such as a flexible urethane foam, a rigid urethane foam, a semi-rigid urethane foam, a polyurethane elastomer, etc. can be used. Various adhesives such as urethane adhesives, cyanoacrylate adhesives, epoxy resin adhesives, polyvinyl acetate adhesives, polyimide adhesives, and the like can also be used after being foamed and cured.

  Various additives such as pigments, antioxidants, metal deactivators, antistatic agents, flame retardants, antifungal agents and fillers can be added to the resin component as necessary.

  The porous solid lubricant as the vibration damping material 10 used in the present invention has a lubricating component and a resin component as essential components, and the lubricating component is applied by the action of external forces such as expansion, contraction, centrifugal force, and expansion of bubbles accompanying a temperature rise. It can be supplied to the necessary site.

  The air bubbles generated when being made porous by foaming are preferably continuous pores, and the lubricating component can be directly supplied from the surface of the resin component to the necessary portions via the continuous pores by the action of external force. In the case of the independent holes, the entire amount of the lubricating component in the resin component may be temporarily taken into the bubbles and may not be sufficiently supplied to the necessary part when necessary.

  In order to occlude the lubricating component inside the resin, it is desirable to employ a reactive impregnation method in which a foaming reaction and a curing reaction are simultaneously performed in the presence of a lubricant. In this way, it is possible to highly fill the inside of the resin with the lubricant, and thereafter, the post-impregnation step of impregnating and replenishing the lubricant can be omitted.

  On the other hand, if the foamed solid is molded in advance and only the impregnation method after impregnation with the lubricant is employed, a sufficient amount of lubricant does not penetrate into the resin, so that the lubricant holding power is not sufficient. If the lubricant is deposited in a short time and used for a long time, the lubricant may be insufficiently supplied. For this reason, the post-impregnation step is preferably employed as an auxiliary means for the reactive impregnation method.

  The reactive impregnation method is preferably performed by using a surfactant such as a commercially available silicone-based foam stabilizer and dispersing each raw material molecule uniformly. Further, it is possible to control the surface tension according to the type and amount of the foam stabilizer, and to control the type of bubbles (continuous type / independent type) and the size of the bubbles. Examples of the surfactant include an anionic surfactant, a nonionic surfactant, a cationic surfactant, an amphoteric surfactant, a silicone surfactant, and a fluorine surfactant.

  The ratio of the lubricating oil (100% by weight) of the lubricating oil is preferably 1% by weight to 95% by weight, and more preferably 5% to 80% by weight. When the ratio of the lubricating oil is less than 1% by weight, it is difficult to sufficiently supply the lubricating oil to a necessary portion. In addition, when the amount is more than 95% by weight, the specific function of the solid lubricant may not be achieved.

  As the lubricating component used in the present invention, any type can be used as long as it does not dissolve the solids forming the foam. For example, lubricating oil, grease, wax, etc. can be used alone or in combination. May be.

  As the lubricating oil used in this invention, paraffinic and naphthenic mineral oils, ester synthetic oils, ether synthetic oils, hydrocarbon synthetic oils, GTL base oils, fluorine oils, silicone oils and the like are generally used. Lubricating oils or mixed oils thereof.

  Examples of the thickener for grease used in the present invention include soaps such as lithium soap, lithium complex soap, calcium soap, calcium complex soap, aluminum soap and aluminum complex soap, and urea compounds such as diurea compounds and polyurea compounds. However, it is not particularly limited.

  Examples of the urea thickener include, but are not limited to, diurea compounds and polyurea compounds.

  The diurea compound is obtained, for example, by reaction of diisocyanate and monoamine. Diisocyanates include phenylene diisocyanate, diphenyl diisocyanate, phenyl diisocyanate, diphenylmethane diisocyanate, octadecane diisocyanate, decane diisocyanate, hexane diisocyanate, and monoamines include octylamine, dodecylamine, hexadecylamine, octadecylamine, oleylamine, aniline, p-Toluidine, cyclohexylamine and the like can be mentioned.

  The polyurea compound can be obtained, for example, by reacting diisocyanate with a monoamine or diamine. Examples of the diisocyanate and monoamine include those similar to those used for the production of the diurea compound. Examples of the diamine include ethylenediamine, propanediamine, butanediamine, hexanediamine, octanediamine, phenylenediamine, tolylenediamine, and xylenediamine. Is mentioned. As the base oil of the grease, the same lubricant oil as described above can be used.

  The wax used in the present invention may be any hydrocarbon synthetic wax, polyethylene wax, fatty acid ester wax, fatty acid amide wax, ketone / amines, hydrogenated oil, and the like. As the oil component used for these waxes, the same oil components as those described above can be used.

  Lubricating components as described above include solid lubricants such as molybdenum disulfide and graphite, friction modifiers such as organic molybdenum, oily agents such as amines, fatty acids, and fats, and antioxidants such as amines and phenols. Agents, rust inhibitors such as petroleum sulfonate, dinonyl naphthalene sulfonate, sorbitan ester, extreme pressure agents such as sulfur and sulfur-phosphorus, antiwear agents such as organic zinc and phosphorus, benzotriazole, sodium nitrite, etc. Various additives such as viscosity index improvers such as metal deactivators, polymethacrylates and polystyrenes may be included.

  As a means for foaming the resin component, a well-known foaming means may be employed. For example, a physical method for heating and vaporizing an organic solvent having a relatively low boiling point such as water, acetone, hexane, etc. A mechanical foaming method that blows active gas from the outside, such as azobisisobutyronitrile (AIBN) or azodicarbonimide (ADCA), which uses a decomposable foaming agent that decomposes by temperature or light and generates nitrogen gas, etc. And the like. Moreover, when it has a highly reactive isocyanate group as a raw material, you may use the chemical foaming by the carbon dioxide produced by the chemical reaction with it and a water molecule.

  In order to use foaming accompanied by such a reaction, it is desirable to use a catalyst as necessary. For example, a tertiary amine catalyst or an organometallic catalyst is used.

  Examples of the tertiary amine catalyst include monoamines, diamines, triamines, cyclic amines, alcohol amines, ether amines, imidazole derivatives, and acid block amine catalysts.

  In addition, as organometallic catalysts, stanaoctate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin marker peptide, dibutyltin thiocarboxylate, dibutyltin maleate, dioctyltin dimarkaptide, dioctyltin thiocarboxylate, lead octenoate, etc. Is mentioned. Moreover, you may mix and use these multiple types for the purpose of adjusting the balance of reaction.

  The expansion ratio of the resin component is desirably 1.1 times or more and less than 200 times. When the expansion ratio is 1.1 times or less, the bubble volume is small, and deformation is not allowed when an external force is applied, or the solid matter is too hard to deform. In addition, when it is 200 times or more, it is difficult to obtain a strength that can withstand external force, which may cause breakage or destruction during use.

  The porous solid lubricant as the damping material 10 may be cast into a mold and molded, or after solidifying at normal pressure, it can be post-processed into a desired shape by cutting or grinding. Also, the inside of the outer joint member of the constant velocity universal joint, usually between the inner joint member and the outer joint member, may be filled with foam to cause a curing reaction, and then the boot is assembled to produce the constant velocity universal joint. it can.

  As described above, in the constant velocity universal joint of the present embodiment, the porous solid lubricant as the vibration damping material 10 enclosed in the outer ring 1 that is the outer joint member has the resin component that is an essential component foamed. Since the surface area is expanded and the lubricating component is occluded in the resin component itself, the holding power of the lubricating component of the resin component is increased. Further, the lubricating component contained in the state of being occluded in the resin component does not rapidly precipitate even when the resin component is deformed by an external force, and appropriately precipitates. As a result, in the present embodiment, since the lubricating component can be efficiently precipitated and used, it is possible to prevent the boot from being deteriorated by the excessively precipitated lubricating component. Even if the boot is broken, the lubrication inside the constant velocity universal joint can be maintained.

  Further, the porous solid lubricant as the damping material 10 is positioned in the axial direction in the space formed by the track groove 1a of the outer ring 1 which is an outer joint member and the track groove 3a of the inner ring 3 which is an inner joint member. Is enclosed in an area restricted by the pocket 5a of the cage 5. As a result, when the torque is transmitted with the minimum necessary damping material 10, the frictional resistance between the ball 4 and the outer ring 1 and the inner ring 3 is suppressed to facilitate torque transmission, and the track groove 1 a of the outer ring 1 and the inner ring 3 are reduced. The vibration transmitted to the outer ring 1 can be mitigated by absorbing the slight vibration of the ball 4 generated between the track groove 3a and the manufacturing cost can be reduced. Even if the boot 7 is broken, the lubrication inside the constant velocity universal joint can be maintained.

  FIG. 1B shows an embodiment in which the present invention is applied to a barfield type constant velocity universal joint, as in FIG. 1A, as a second embodiment of the present invention. Note that in this embodiment, parts having the same parts, functions, and forms as those in FIG. 1A are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the second embodiment, a lubricating component including a lubricating oil and a resin component are essential components in both or either one of the space including the track groove 1a of the outer ring 1 and the space including the track groove 3a of the inner ring 3. In addition, a damping material 10a made of a porous solid lubricant, which is a solid material in which the resin component is foamed and made porous, and has the lubricating component occluded inside the resin, is enclosed.

  In the constant velocity universal joint of the present embodiment, a porous solid lubricant as the damping material 10a is enclosed in a space formed by the track groove 1a of the outer ring 1 and the track groove 3a of the inner ring 3. As a result, during torque transmission, the frictional resistance between the track groove 1a and the track groove 3a with which the ball 4 moves and contacts is suppressed to facilitate torque transmission, and the outer groove 1 track groove 1a and inner ring 3 track groove 3a. The vibration transmitted to the outer ring 1 can be reduced by absorbing the slight vibration of the ball 4 generated between the outer ring 1 and the outer ring 1. Even if the boot 7 is broken, the lubrication inside the constant velocity universal joint can be maintained.

  The application of the vibration damping material according to the present invention shown in FIGS. 1A and 1B can also be applied to various other constant velocity universal joints. 2A and 2B show a double offset type constant velocity universal joint (DOJ) as one of sliding type constant velocity universal joints as third and fourth embodiments of the present invention. 3 (A) and FIG. 3 (B) show a cross-groove type constant velocity universal joint (LJ) as one of sliding type constant velocity universal joints as fifth and sixth embodiments of the present invention. In the above embodiment, in the embodiment using the same type of constant velocity universal joint, parts having the same parts, functions, and forms are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 2A shows an embodiment in which the present invention is applied to a double offset constant velocity universal joint (DOJ) which is one of sliding type constant velocity universal joints as a third embodiment of the present invention.

  The constant velocity universal joint includes an outer ring 15 that is an outer joint member, an inner ring 17 that is an inner joint member, a ball 18, and a cage 19. A plurality of linear track grooves 15 a extending in the axial direction are formed on the cylindrical inner peripheral surface of the outer ring 15, and a plurality of linear tracks paired with the track grooves 15 a of the outer ring 15 are formed on the spherical outer peripheral surface of the inner ring 17. A groove 17a is formed. Between the track groove 15a of the outer ring 15 and the track groove 17a of the inner ring 17, there are three, four, five, six, seven or eight balls 18 interposed. The ball 18 is held in a pocket 19 a of the cage 19. In this constant velocity universal joint, when a rotational torque is generated and the outer shaft 20 is rotated, the shaft 21 is rotated via the ball 18 following the rotation.

  In the present embodiment, the outer ring 15 has a solid component in which a lubricating component including a lubricating oil and a resin component are essential components, the resin component is foamed and made porous, and the lubricating component is The damping material 22 made of a porous solid lubricant occluded inside the resin surrounds the ball 18, that is, the space formed by the track groove 15a of the outer ring 15 and the track groove 17a of the inner ring 17, The axial position is enclosed in a region regulated by the pocket 19 a of the cage 19. Note that the operation and effect of the present embodiment are the same as those of the first embodiment shown in FIG.

  FIG. 2B shows a fourth embodiment in which the present invention is applied to a double offset type constant velocity universal joint, as in FIG. 2A.

  In the present embodiment, the resin containing the lubricating component and the resin component containing the lubricating oil as essential components in the space including the track groove 15a of the outer ring 15 and the space including the track groove 17a of the inner ring 17 or any one of the spaces is provided. A vibration damping material 22a made of a porous solid lubricant, which is a solid material that is made porous by foaming the component and occludes the lubricating component inside the resin, is enclosed. Note that the operation and effect of the present embodiment are the same as those of the second embodiment shown in FIG.

  FIG. 3A shows an embodiment in which the present invention is applied to a cross groove type constant velocity universal joint (LJ) which is one of sliding type constant velocity universal joints as a fifth embodiment of the present invention.

  The constant velocity universal joint includes an outer ring 31 that is an outer joint member, an inner ring 32 that is an inner joint member, a ball 33, and a cage 34. A stub shaft 36 is spline-fitted in the center hole 35 of the inner ring 32, and torque transmission between the inner ring 32 and the stub shaft 36 is possible by this spline fitting. The stub shaft 36 is prevented from coming off by a snap ring 37.

  A plurality of linear track grooves 31 a are formed on the inner peripheral surface of the outer ring 31, and a plurality of linear track grooves 32 a are formed on the outer peripheral surface of the inner ring 32, and the track grooves 31 a and the inner ring 32 of the outer ring 31 are formed. The track groove 32a is inclined at a predetermined angle with respect to the axis. Four, six, eight, or ten balls 33 are interposed at the intersections of the track grooves 31a of the outer ring 31 and the track grooves 32a of the inner ring 32. The balls 33 are connected to the outer ring 31 and the inner ring. 32 is held in a pocket 34a of the cage 34 positioned between the two.

  In addition, an end plate 38 for preventing leakage of grease filled in the joint and preventing entry of foreign matters is provided at one end side in the axial direction of the outer ring 31 with bolts (not shown) from the insertion side of the stub shaft 36. It is fixed by tightening. On the other hand, a sealing device is mounted between the other axial end of the outer ring 31 and the stub shaft 36.

  This sealing device includes a boot 39 and a metal boot adapter 40. The boot 39 has a small end portion and a large end portion, and has a shape folded back into a U shape in the middle. However, the present invention is not limited to this shape, and various things such as a boot having a bellows shape can be applied. The boot adapter 40 has a cylindrical shape, has a flange fitted to the outer peripheral surface of the outer ring 31 at one end, and is fixed by bolting from the insertion side of the stub shaft 36 together with the end plate 38. The small end portion of the boot 39 is fitted to the stub shaft 36 and further fixed by the boot band 41, and the large end portion is fixed by crimping to the end opposite to the flange side of the boot adapter 40. The However, it is not restricted to this fixing method, For example, you may fix with a boot band.

  Now, in the present embodiment, the outer ring 31 has a lubrication component including a lubricating oil and a resin component as essential components, and the resin component is a solid material foamed and made porous, and the lubrication component is contained in the outer ring 31. The damping material 42 made of a porous solid lubricant occluded inside the resin surrounds the ball 33, that is, the space formed by the track groove 31a of the outer ring 31 and the track groove 32a of the inner ring 32, The axial position of the cage 34 is enclosed in a region regulated by the pocket 34a. Note that the operation and effect of the present embodiment are the same as those of the first embodiment shown in FIG.

  FIG. 3B shows, as a sixth embodiment of the present invention, an embodiment in which the present invention is applied to a cross-groove type constant velocity universal joint, as in FIG. 3A.

  In the present embodiment, the resin containing the lubricating component and the resin component containing lubricating oil as essential components in the space including the track groove 31a of the outer ring 31 and the space including the track groove 32a of the inner ring 32, or any one of them, is used. A vibration damping material 42a made of a porous solid lubricant, which is a solid material which is foamed and made porous, and has the lubricating component occluded inside the resin, is enclosed. Note that the operation and effect of the present embodiment are the same as those of the second embodiment shown in FIG.

  As mentioned above, although embodiment of this invention was described, these embodiment is an illustration to the last, and includes all the matters within the meaning and range as described in a claim.

  For example, since a lubricating oil, grease, wax, or the like can be used as a lubricating component of the porous solid lubricant according to the present invention, the embodiment of the present invention is applied in combination with a lubricant such as grease. Can do.

  The raw materials used in the examples and comparative examples are listed below, and the composition and measurement results of the solid lubricant constituting the vibration damping material are shown in Table 1.

(A) Urethane prepolymer (Daicel Chemical Industries, Plaxel EP-1130)
(B) Amine-based curing agent (Ihara Chemical Co., Ltd .: Iharacamine MT)
(C) Water (ion exchange water)
(D) Silicone type foam stabilizer (manufactured by Toray Dow Co., Ltd .: SRX298)
(E) Urea grease (Shin Nippon Oil Co., Ltd .: Pyronock Universal N6C)
(F) Isocyanate (manufactured by Nippon Polyurethane Co., Ltd .: Coronate T80)
(G) Polyether polyol (Asahi Glass Co., Ltd .: Preminol SX4004)
(H) Amine-based catalyst (Tosoh Corporation: TOYOCAT DB2)
(I) Lubricating oil (manufactured by Nippon Oil Corporation: Turbine 100)

[Example 1]
As shown in FIG. 1 (A), an inner ring 3, a cage 5 and a ball 4 were assembled to an outer ring 1 of a constant velocity universal joint (manufactured by NTN: EBJ82). Separately, silicone foam stabilizers and urea grease were added to the urethane prepolymer in the amount (composition) shown in Table 1, and the mixture was well stirred at 120 ° C. An amine-based curing agent is added to this, stirred, and then water as a foaming agent is added to surround the ball 4, that is, within the space formed by the track groove 1 a of the outer ring 1 and the track groove 3 a of the inner ring 3. The solid lubricant is filled and foamed in the region where the axial position is regulated by the pocket 5a of the cage 5, and this is left to stand in a thermostatic bath set at 120 ° C. for 1 hour to be cured. The constant velocity universal joint holding the porous solid lubricant was obtained.

[Example 2]
In the component amount (composition) shown in Table 1, polyether foam polyol with silicone foam stabilizer, mineral oil,
An amine catalyst and water as a blowing agent were added, and the mixture was heated at 90 ° C. and stirred well. Isocyanate is added to this, and the mixture is well stirred, so that the axial position of the space surrounding the ball 4, that is, the space formed by the track groove 1 a of the outer ring 1 and the track groove 3 a of the inner ring 3 is the pocket 5 a of the cage 5. The solid lubricant was filled and foamed in the region regulated by the above, and left in a constant temperature bath set at 90 ° C. for 15 minutes to obtain a constant velocity universal joint holding the porous solid lubricant as the damping material 10.

[Comparative Example 1]
A constant velocity universal joint holding a solid lubricant was obtained in the same manner as in Example 1 except that the non-foamed lubricant was used in the amount (composition) shown in Table 1.

[Comparative Example 2]
Of the components (compositions) shown in Table 1, a foam was synthesized in the same manner as in Example 2 except for the mineral oil. The oil was impregnated later to obtain a constant velocity universal joint holding a post-impregnation type foaming lubricant. With respect to the foams obtained in Examples 1 and 2 and Comparative Examples 1 and 2, the value obtained by dividing the volume after foaming by the volume before foaming was determined as the foaming ratio and shown in Table 1.

  About the constant velocity universal joint of the obtained Example and a comparative example, a durability test was performed on the conditions of torque 245Nm, angle 6deg, and rotation speed 1000r / min, and the degree of damage or destruction of solid lubricant after rotating for 10 hours Was evaluated by visual observation and observation using an optical microscope. The results are as follows: ◯: No damage or breakage and continuous use was possible, △: Solid lubricant was not destroyed but the oil separation was excessive, x: Solid lubricant It was evaluated that it was damaged or destroyed and could not be used continuously.

  As is apparent from the results shown in Table 1, the lubricant in Example 1 having the same composition and filled with the foamed solid lubricant was more broken than the Comparative Example 1 filled with the non-foamable solid lubricant. It has durability that can be used continuously for a long time without damage.

  Further, Comparative Example 2 using a solid lubricant in which mineral oil was retained only in the post-impregnation step even in the foamed resin of the same composition was used in Example 2 using a solid lubricant in which mineral oil was occluded in the resin simultaneously with foaming. It can be seen that the amount of oil separated under the same centrifugal force was larger than that, and excess oil that did not contribute to lubrication was supplied. On the other hand, in the constant velocity universal joint of Example 2, the lubrication component is sufficiently occluded inside the resin in the reaction type solid lubricant, and the oil separation speed is appropriate even if centrifugal force acts, and the long time It turns out that it has the durability which can be used.

  Also, from these examples and comparative examples, the lubricating component is occluded inside the resin by the reactive impregnation simultaneously with foaming, and the lubricating oil is retained in the bubbles simply by impregnating the foamed resin molding into the lubricating oil. It can be seen that the oil retention by occlusion is higher than that of the case.

The present invention is applied to a Barfield type constant velocity universal joint which is one of fixed type constant velocity universal joints, and FIG. 5A is a sectional view showing a first embodiment. (B) is sectional drawing which shows 2nd Embodiment. The present invention is applied to a double offset type constant velocity universal joint, which is one of sliding type constant velocity universal joints, and (A) is a cross-sectional view showing a third embodiment. (B) is sectional drawing which shows 4th Embodiment. The present invention is applied to a cross-groove type constant velocity universal joint which is one of sliding type constant velocity universal joints, and (A) is a cross-sectional view showing a fifth embodiment. (B) is sectional drawing which shows 6th Embodiment.

Explanation of symbols

1, 15, 31 Outer ring (outer joint member)
3, 17, 32 Inner ring (inner joint member)
4, 18, 33 balls (rolling elements)
5, 19, 34 Cage 5a, 19a, 34a Pocket 1a, 3a, 15a, 17a, 31a, 32a Track groove 10, 10a, 22, 22a, 42, 42a Damping material

Claims (7)

An outer joint member having a track groove formed on the inner peripheral surface, an inner joint member having a track groove formed on the outer peripheral surface disposed inside the outer joint member, the track groove of the outer joint member, and the inner joint member. A rolling element interposed between the track grooves,
A vibration damping material comprising a porous solid lubricant containing a lubricating component including a lubricating oil and a resin component as essential components, the resin component being foamed and porous, and the lubricating component being occluded inside the resin. A constant velocity universal joint characterized in that a material is enclosed in a space surrounding the rolling element. An outer joint member having a track groove formed on the inner peripheral surface, an inner joint member having a track groove formed on the outer peripheral surface disposed inside the outer joint member, the track groove of the outer joint member, and the inner joint member. A rolling element interposed between the track grooves,
A vibration damping material comprising a porous solid lubricant containing a lubricating component including a lubricating oil and a resin component as essential components, the resin component being foamed and porous, and the lubricating component being occluded inside the resin. A constant velocity universal joint characterized in that a material is enclosed in a space including a track groove of the outer joint member and / or a space including a track groove of the inner joint member.   The outer joint member is formed with a plurality of track grooves on the spherical inner peripheral surface, and the inner joint member is formed with a plurality of track grooves paired with the track grooves of the outer joint member on the spherical outer peripheral surface. The rolling element is a ball interposed between the track groove of the outer joint member and the track groove of the inner joint member, and a cage for holding the ball is interposed between the outer joint member and the inner joint member. The constant velocity universal joint according to claim 1, wherein the constant velocity universal joint is provided.   The outer joint member is formed with a plurality of linear track grooves extending in the axial direction on a cylindrical inner peripheral surface, and the inner joint member is paired with a track groove of the outer joint member on a spherical outer peripheral surface. A plurality of linear track grooves are formed, and the rolling elements are balls interposed between the track grooves of the outer joint member and the track grooves of the inner joint member, and between the outer joint member and the inner joint member. 3. The constant velocity universal joint according to claim 1, further comprising a cage for holding the ball.   The outer joint member has a plurality of linear track grooves formed on the inner peripheral surface, and the inner joint member has a plurality of linear track grooves paired with the track grooves of the outer joint member on the outer peripheral surface. In addition, the track groove of the outer joint member and the track groove of the inner joint member are inclined at a predetermined angle with respect to the axis, and the rolling element is formed of the track groove of the outer joint member and the inner groove. 2. A ball interposed at an intersection of a joint member with a track groove, and a cage for holding the ball interposed between the outer joint member and the inner joint member. 2. The constant velocity universal joint according to any one of the above.   5. The ball according to claim 3, wherein the number of balls is any number selected from 3, 4, 5, 6, 7, or 8. Fast universal joint.   6. The constant velocity universal joint according to claim 5, wherein the number of the balls is any number selected from 4, 6, 8, or 10.