JP2010270864A - Constant velocity universal joint - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cost-effective constant velocity universal joint which improves an cooling effect of the constant velocity universal joint, supplements a lubricating function even when a lubricating component from a foamed solid lubricant becomes insufficient, and maintains excellent lubricity over a long period of time even when used at a high operating angle. <P>SOLUTION: The constant velocity universal joint 1 includes an outer member 2, a track groove 2a provided on the inner diameter surface of the outer member 2, torque transmission members 4 which are rolled along the track groove 2a, a shaft 6 which transmits a rotational torque to the torque transmission member 4, and a seal structure member 8 which covers the end surface of the opening side of the outer member 2, without a boot. The seal structure member 8 has an opening through which the shaft 6 passes. Inside the universal joint 1, a foamed solid lubricant 7, which includes a lubricating component in a porous resin formed by foaming and hardening, and grease 9 for auxiliary lubrication coexist. The grease 9 for the auxiliary lubrication contains at least wax whose melting point is 70 to 150°C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a constant velocity universal joint (joint) used in a power transmission system of automobiles, industrial machines, office equipment and the like.

  Generally, a lubricant is used in a sliding part and a rotating part of most machines represented by automobiles and industrial machines. Lubricants can be broadly divided into liquid lubricants and solid lubricants. Grease with increased lubricating oil and shape retention, and solids that retain liquid lubricant and prevent its scattering and dripping. Lubricants are also known.

  For example, a solid lubricant in which ultra-high molecular weight polyolefin or urethane resin and its curing agent are mixed in lubricating oil or grease, and a liquid lubricant component is held between the resin molecules to gradually exude physical properties. It is known (see Patent Documents 1 to 3). Also known is a self-lubricating polyurethane elastomer obtained by reacting a polyurethane raw material polyol and diisocyanate in a lubricating component (see Patent Document 4). When such solid lubricant is sealed in a bearing and solidified, it gradually exudes lubricating oil. If this is used, maintenance for replenishing the lubricating oil becomes unnecessary, and there is a lot of moisture. In many cases, it is useful for extending the life of the bearing even in environments where it is used or where there is a strong inertia.

  If such a solid lubricant is used at a site where external stress such as compression or bending is repeatedly applied at a high frequency such as the drive part of a constant velocity universal joint, it is very large to deform following the compression and bending. A force is required, or a very large stress is applied to the solid lubricant, and a mechanical strength is also required in a portion holding the solid lubricant. However, since the strength and the filling rate of the solid lubricant are usually contradictory, it is difficult to maintain the lubricant at a high filling rate, and there is a possibility that the extension of the service life may be hindered.

  Therefore, there is a demand for a solid lubricant that can be easily used even at sites where external stress such as compression and bending repeatedly occurs at a high frequency. As an example of dealing with this, an oil-containing solid lubricant is known in which an oil-containing foam in which lubricating oil is held in the pores of a foamed flexible resin is filled in a bearing or a constant velocity joint and used (Patent Document 5). reference). In addition, since this oil-containing solid lubricant has a small lubricating oil retention force, there is also a foamed solid lubricant that can absorb the lubricating oil not only in the pores but also between the resin molecules and improved the lubricating oil retention force. It has been proposed (see Patent Document 6).

  On the other hand, the constant velocity joint has a bellows-shaped boot for the purpose of preventing the lubricant encapsulated in the joint from flowing out and preventing water and dust from entering. In a constant velocity joint having a bellows-shaped boot, damage due to fatigue or wear is a problem in a mountain or a valley. Therefore, a boot that reduces these problems has also been proposed (see Patent Document 9).

  Known boots include CR boots and resin boots (see Patent Document 7 and Patent Document 8) attached to a fixed type constant velocity joint. It can be confirmed that there is no lubricant outflow prevention mechanism. In addition, a universal joint that suppresses the outflow of a lubricating component to the boot side by forming a partition plate or a coating has been proposed (see Patent Document 12). In addition, a one-touch type boot band used for boots (see Patent Document 10) and a right and left caulking band applied to resin boots are known (see Patent Document 11).

  FIGS. 13 and 14 show a state in which a conventional boot is mounted on a fixed type and a sliding type constant velocity universal joint.

  FIG. 13 is a partially cutaway sectional view of a ball fixed joint (hereinafter referred to as BJ) of a fixed type constant velocity universal joint. As shown in FIG. 13, the BJ 21 has six track grooves 22a, 23a in the axial direction at equal angles on the inner surface of the outer member (also called outer ring) 22 and the outer surface of the spherical inner member (also called inner ring) 23. A torque transmission member 24 formed and incorporated between the track grooves 22a and 23a is supported by a cage 25. Further, grease 29 is enclosed in a space surrounded by the outer member 22, the spherical inner member 23, the torque transmission member 24, the cage 25, and the shaft 26, and this grease 29 is prevented from flowing out. A bellows-shaped boot 30 is provided. One end of the boot 30 is provided with an outer peripheral surface of the outer member 22 on the opening side outer peripheral surface by a left and right caulking band 30a, and the other end is provided with an outer peripheral surface of the shaft 26 facing the opening side of the outer member 22, Each is attached by a fastening band 30b.

  FIG. 14 is a partially cutaway sectional view of a tripod joint (hereinafter referred to as TJ) of a sliding type constant velocity universal joint. As shown in FIG. 14, the TJ 31 is a tripod member in which three cylindrical track grooves 32 a in the axial direction are formed at equal angles on the inner surface of an outer member (also referred to as an outer ring) 32 and incorporated inside the outer member 32. 33 is provided with three leg shafts 34a, and a spherical roller 34 as a torque transmission member is fitted to the outside of each leg shaft 34a, and a needle is provided between the spherical roller 34 as the torque transmission member and the leg shaft 34a. 35, a spherical roller 34 as a torque transmission member is supported rotatably and slidable in the axial direction, and the spherical roller 34 as a torque transmission member is fitted in the track groove 32a. Grease 39 is enclosed in a space surrounded by the outer member 32, tripod member 33, and shaft 36, and a bellows-shaped boot 40 for preventing the grease 39 from flowing out is provided. One end of the boot 40 has a one-touch type band 40a on the opening side outer peripheral surface of the outer member 32, and the other end part has a one-touch type band 40b on the outer peripheral surface of the shaft 36 facing the opening side of the outer member 32. Are attached respectively.

JP-A-6-41569 JP-A-6-172770 JP 2000-319681 A JP-A-11-286601 Japanese Patent Laid-Open No. 9-42297 JP 2007-177226 A JP 2005-337303 A JP 2007-239879 A JP 2005-83439 A Japanese Utility Model Publication No. 7-38709 JP-A-8-159108 JP 2008-32217 A

  However, at present, boots are used for constant velocity joints, but since heat generated in the joints during continuous driving is difficult to dissipate, there is a concern that the durability of the joints may be reduced. In addition, since CR boots and resin boots used as constant velocity joint boots have a bellows shape, at high operating angles, the boots are deformed and the boots are in contact with each other. The valley and the shaft come into contact. For this reason, when used for a long time, the boot may be damaged due to fatigue or wear at these portions, and the internal lubricant may flow out to the outside.

  In the conventional boot shape, the grease in the joint flows out from the inner surface of the outer ring member to the boot side due to the centrifugal force during rotation, and the grease is insufficient in the joint. As a result, there is a concern that grease on the contact surface is insufficient, heat generation due to friction increases, and early contact surface peeling occurs. In order not to cause a shortage of grease, grease is sealed in both the joint and the boot to suppress the depletion of grease on the contact surface. However, an increase in cost due to the large amount of grease is a problem. Yes.

  One of the solutions for reducing the amount of grease enclosed is the use of the foamed solid lubricant disclosed in Patent Document 6, but even when the foamed solid lubricant is used, heat generation due to contact between components occurs when used at a high operating angle. As a result, the viscosity of the lubricating component decreases, and the lubricating component flows out to the boot side. In addition, there is a universal joint formed with a partition plate and a film disclosed in Patent Document 12 as a means for suppressing the outflow of a lubricating component to the boot side, but the combined use of these partition plate and the boot increases costs. There is a problem that leads to.

  Further, the constant velocity joint enclosing the foamed solid lubricant disclosed in Patent Document 6 may have a small amount of release of the lubricant due to an external force or a temperature rise depending on how it is used. In view of durability, it is desirable that the release of the lubricating component from the resin component is the minimum necessary. If the release speed of the lubricating component is small, the speed at which the necessary amount of lubricant reaches the sliding portion becomes slow. For this reason, the lubricant is depleted and wear and lubrication may be caused even in the sliding portion.

  The present invention was made in order to cope with such problems, and while improving the cooling effect of the constant velocity universal joint, it can supplement the lubricating function even when the lubricating component from the foamed solid lubricant is insufficient, It is an object of the present invention to provide a long-life and low-cost constant velocity universal joint that can maintain excellent lubricity over a long period of time even when used at a high operating angle.

  The constant velocity universal joint of the present invention includes an outer member, a track groove provided on an inner diameter surface of the outer member, a torque transmission member that rolls along the track groove, and a rotational torque applied to the torque transmission member. A constant velocity universal joint having no boot, the seal structure member having an opening through which the shaft passes. The constant velocity universal joint includes at least a foamed solid lubricant including a lubricating component in a resin that is foamed and cured to be porous, and a wax having a melting point of 70 to 150 ° C. It is characterized by coexistence with auxiliary lubricating grease.

  The opening of the seal structure member has a shape that prevents the seal structure member from interfering with a joint constituent member including the shaft and the torque transmission member when the constant velocity universal joint is operated. For example, the opening of the seal structural member has a circular cross-section in the axial direction that is concentric with the shaft, and the diameter of the opening is at the maximum operating angle of the constant velocity universal joint. The length is such that the structural member does not contact.

  The seal structure member is made of a rubber-like elastic material and has a shape that interferes with the cage, the inner member, the shaft, or the torque transmission member of the constant velocity universal joint when the constant velocity universal joint is operated. Features. For example, the seal structure member has a shape that contacts the shaft without being fixed to the constant velocity universal joint at an operating angle of 0 °.

  The seal structure member is attached to the outer diameter portion of the outer member by a band, press-fitting, or bonding.

  The constant velocity universal joint is used for equipment used indoors.

  The wax is at least one selected from fatty acid amides and hydrogenated oils.

  The foamed solid lubricant is characterized in that the resin foamed and cured to become porous has rubber-like elasticity, and the lubricating component contained in the resin has exudability due to deformation of the rubber-like elastic body. To do. In addition, the open cell ratio after foaming / curing of the resin foamed and cured to be porous is 50% or more.

  The foamed solid lubricant is obtained by foaming and curing a mixture containing the lubricating component, the resin, a curing agent, and a foaming agent, and the resin contains 2% by weight to 6% by weight of isocyanate groups in the molecule. It is a urethane prepolymer containing less, the foaming agent is water, and the mixture contains 20 to 80% by weight of the lubricating component with respect to the whole mixture.

  The urethane prepolymer is at least one urethane prepolymer selected from an ester urethane prepolymer, a caprolactone urethane prepolymer, and an ether urethane prepolymer.

  The ratio of the isocyanate group and the functional group of the curing agent that reacts with the isocyanate group is an equivalent ratio (functional group of the curing agent / NCO) = 1 / (1.1 to 2.5). . The ratio of the hydroxyl group of water to the functional group of the curing agent is an equivalent ratio (hydroxyl group of water / functional group of the curing agent) = 1 / (0.7 to 2.0).

  The curing agent is an aromatic polyamino compound. Further, the aromatic polyamino compound is an aromatic polyamino compound having a substituent at a position adjacent to the amino group.

  The constant velocity universal joint of the present invention includes an outer member, a track groove provided on an inner diameter surface of the outer member, a torque transmission member that rolls along the track groove, and a rotational torque applied to the torque transmission member. And a seal structure member that covers the opening-side end surface of the outer member, and has no boot. The seal structure member has an opening through which the shaft passes, and the like. The speed universal joint includes a foamed solid lubricant containing a lubricating component in a resin that is foamed and cured to become porous, and a grease for auxiliary lubrication containing at least a wax having a melting point of 70 to 150 ° C. Therefore, it is possible to improve the effect of preventing the lubricant from flowing out, the effect of cooling the constant velocity universal joint, and the effect of maintaining the lubricity in the sliding portion, and supply at a low cost. Further, a long-lived constant velocity universal joint can be obtained by the above synergistic effect.

  The improvement of the lubrication component outflow prevention effect is achieved by using a seal structure member in place of the conventional boot, and the boot mechanical due to fatigue, wear, etc., which has been a problem when operating at a high operating angle in the conventional boot. This is because the problem of the lubricant flowing out of the boot due to damage can be solved. In addition, the lubricating oil that oozes out from the resin during operation of the constant velocity universal joint partially moves toward the opening end face of the inner surface of the outer member due to centrifugal force, but is blocked by the sealing structure member at the opening end face of the outer member. Since it is absorbed into the resin again, it is possible to prevent the seal structure member from flowing out from the opening.

  Also, during operation of the constant velocity universal joint, the auxiliary lubrication grease also partially moves toward the opening end surface of the inner surface of the outer member by centrifugal force. Is prevented from flowing out. For example, a lubricating oil that oozes from auxiliary lubricating grease and foamed solid lubricant by forming the seal structure member from a rubber-like elastic material and having a shape that contacts the shaft or the like at an operating angle of the constant velocity universal joint of 0 °. Can be effectively prevented.

  The improvement of the cooling effect is due to the improvement of the cooling effect of the constant velocity universal joint by the heat generation of the constant velocity universal joint caused by the friction on the sliding surface being radiated from the opening of the seal structure member.

  As for the improvement of the effect of maintaining the lubricity in the sliding part, the lubricating component is gradually released from the foamed solid lubricant to the part that requires the lubricating component, and the oozing out of the lubricating component from the foamed solid lubricant is insufficient. Even when the lubricating component is exhausted, the use of auxiliary lubricating grease can compensate for the lack of the lubricating component that oozes out from the foamed solid lubricant. This is because the lubricant can be prevented from flowing out of the quick universal joint. In particular, since a predetermined wax component is added to the auxiliary lubricating grease, the auxiliary lubricating grease is difficult to move from the sliding portion even when an external force such as a centrifugal force is applied. Even if the sliding part is in metal contact due to lack of lubrication component, the temperature rises due to metal contact, so that the wax component in the auxiliary lubrication grease melts and the fluidity of the auxiliary lubrication grease improves, thereby causing sliding. Lubricant is quickly supplied to the moving part, and a smooth lubrication state can be maintained.

  The release of the lubricating component from the foamed solid lubricant has the flexibility that the foamed solid lubricant obtained by foaming and curing can be freely deformed in response to the operation of the constant velocity universal joint, for example, The foamed solid lubricant is deformed by external factors such as compression, bending, torsion, and expansion associated with the operation of the constant velocity universal joint, and the lubrication component retained in the resin is required at the required location at the required timing. This is due to oozing out in the minimum amount.

  Regarding the supply of constant velocity universal joints at low cost, the amount of lubricant enclosed in constant velocity universal joints can be reduced by using foamed solid lubricant, the shape of the seal structure member is simple and compact, and the shaft is sealed. This is because the manufacturing cost can be reduced, for example, at least one band can be reduced.

  As a result, the constant velocity universal joint of the present invention can reduce the cost by reducing the amount of lubricant used compared to the conventional one, prevent the lubricant from flowing out, and make the constant velocity universal joint lighter and more compact. Therefore, it is possible to realize a technology with high social importance not only from an economically advantageous industrial aspect but also from a plurality of viewpoints, such as a reduction in environmental load and a degree of freedom in design.

It is sectional drawing which shows one Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is sectional drawing which shows the other Example of the universal joint of this invention. It is a figure which shows the other Example of the universal joint of this invention. It is a figure which shows the other Example of the universal joint of this invention. It is a figure which shows the other Example of the universal joint of this invention. It is a partially cutaway sectional view of BJ. It is a partially cutaway sectional view of TJ.

  Embodiments of the constant velocity universal joint of the present invention will be described below with reference to the drawings. 1 to 4 and FIGS. 7 to 12 are diagrams showing examples of applying the constant velocity universal joint of the present invention to BJ1 which is a fixed type constant velocity universal joint. For example, as shown in FIG. 1, BJ1 includes an outer member (also referred to as an outer ring) 2 and six or eight track grooves 2a provided on the inner diameter surface of the outer member 2 at equal angles in the axial direction. A spherical inner member 3 (also referred to as an inner ring), six or eight track grooves 3a provided at equal angles in the axial direction on the outer diameter surface of the inner member 3, and these track grooves 2a, 3a A torque transmission member 4 that rolls along the shaft, a cage 5 that supports the torque transmission member 4, a shaft 6 that transmits rotational torque to the inner member 3, and a seal structure that covers the opening-side end surface of the outer member 2. And a member 8. The seal structure member 8 has an opening through which the shaft 6 penetrates at the center, and is attached to the outer diameter surface of the outer member 2 with a right and left caulking band 10. Inside the BJ 1, a foamed solid lubricant 7 is enclosed in a space surrounded by the outer member 2, the inner member 3, the torque transmission member 4, the cage 5, and the shaft 6, and the outer member 2 is filled with auxiliary lubricating grease 9 and coexists. In the constant velocity universal joint of the present invention, the seal structure member 8 is used instead of the boot.

  5 and 6 are views showing an example in which the constant velocity universal joint of the present invention is applied to TJ11 which is a sliding type constant velocity universal joint. For example, as shown in FIG. 5, the TJ 11 includes an outer member (also referred to as an outer ring) 12, three cylindrical track grooves 12 a provided on the inner diameter surface of the outer member 12 at equal angles in the axial direction, The tripod member 13 having three leg shafts 14a incorporated inside the outer member 12, the spherical roller 14 fitted to the outside of each leg shaft 14a, and the spherical roller 14 and the leg shaft 14a. The needle 15 that supports the spherical roller 14 so as to be rotatable and slidable in the axial direction, the shaft 16 that transmits the rotational torque to the tripod member 13, and the seal structure member 18 that covers the opening-side end surface of the outer member 12. And. The seal structure member 18 has an opening through which the shaft 16 penetrates at the center, and is attached to the outer diameter surface of the outer member 12 with a one-touch type band 20. Inside the TJ 11, a foamed solid lubricant 17 is enclosed in a space surrounded by the outer member 12, tripod member 13, leg shaft 14 a, spherical roller 14, needle 15, and shaft 16, Auxiliary lubricating grease 19 is sealed at the bottom of the outer member 12 and coexists.

  The seal structure member is not in the shape of a bellows like a conventional boot, but in a shape that covers the opening end face of the joint, and the outer member outer diameter portion is sealed with the seal structure member. On the other hand, the shaft portion has a shape in which the central portion is opened on the outer member opening end face side without sealing with the seal structure member. Thereby, a cooling effect improves and it leads to the lifetime improvement of a joint. In addition, mechanical damage such as fatigue and wear that occurs in the peaks and valleys peculiar to the bellows shape, which has been a problem when using boots, can be avoided. This can be prevented by using the seal structure member. Furthermore, since the foamed solid lubricant can be concentrated and encapsulated around the torque transmission member that requires the lubricant, the amount of the lubricant to be encapsulated can be reduced, leading to cost reduction and weight reduction.

  If the seal structure member interferes with the joint component including the shaft and the torque transmission member during operation of the constant velocity universal joint, the seal structure member may be damaged and the lubricant may flow out and leak. It is preferable that the shape of the opening is a shape that does not interfere with the joint constituent member during operation of the constant velocity universal joint.

  Examples of materials that can be used for the seal structure member in the present invention include resin materials, metal materials, rubber-like elastic materials, and the like. These can be properly used as seal structure materials for constant velocity universal joints according to required physical properties such as mechanical strength, flexibility, and compatibility with a solid foam lubricant.

  Further, in the constant velocity universal joint of the present invention, the auxiliary lubricating grease coexisting with the foamed solid lubricant inside has higher fluidity than the foamed solid lubricant, so the center part of the seal structure member is opened and the joint structure It is difficult to prevent the auxiliary lubricating grease from flowing out only by using a sealing structure member that does not interfere with the member at all. Therefore, by using a rubber-like elastic material for the seal structure member, it is possible to allow the structure to allow interference with the joint constituent member during the operation of the constant velocity universal joint, thereby improving the effect of preventing the lubricant from flowing out.

  In the present invention, examples of the method of mounting the seal structure member on the outer member outer diameter portion include a method of mounting by a band, a method of mounting by press-fitting, and a method of mounting by joining.

  The embodiment of the constant velocity universal joint of the present invention will be described in detail with reference to FIGS. FIG. 1 is a view showing an example of an embodiment of the present invention, and is a view showing a state at an operating angle of 0 ° of BJ1 which is a fixed type constant velocity universal joint to which a seal structure member is applied. The auxiliary lubricating grease and the lubricating oil that has oozed out of the resin during the operation of the BJ1 move from the opening end surface of the inner surface of the outer member 2 by centrifugal force, but the sealing structure provided on the opening end surface of the outer member 2 Since it is blocked by the member 8 and the lubricating component is absorbed again into the resin, it is possible to prevent the auxiliary lubricating grease and the lubricating component from flowing out from the opening of the seal structure member 8.

  Moreover, as shown in FIG. 1, it is preferable to form the film 7a on the end surface of the foamed solid lubricant 7 on the seal structure member side. When the constant velocity universal joint is used, the opening area increases as the operating angle increases, and the lubricant outflow prevention effect decreases. Therefore, it is possible to further improve the effect of preventing the outflow of the lubricating component by forming a coating on the end surface of the foamed solid lubricant on the seal structure member side (end surface on the outer member opening side).

  The coating is preferably formed using a composition having the same resin component as the resin of the foamed solid lubricant described later. Thereby, it is excellent in the adhesiveness of a film and a foaming solid lubricant. Further, by adopting a resin or rubber having rubber-like elasticity as the resin component of the foamed solid lubricant and the film, damage due to compression / bending can be prevented.

  FIG. 2 is a diagram showing another example of the embodiment of the present invention, and is a diagram showing the opening diameter D1 and the shape of the seal structure member 8 in FIG. The seal structure member 8 is set to have an opening diameter D1 and a shape so as not to interfere (contact) the shaft 6, the cage 5, the torque transmission member 4 or the inner member 3 at the maximum operating angle during use. Is preferred. Note that the axial section of the opening is circular, and the center position of the opening is the same as the center position of the axial section of the shaft at an operating angle of 0 °.

  3 and 4 are diagrams showing another example of the embodiment of the present invention, and are diagrams showing an example of the shape of the seal structure member 8 in FIG. 1 and FIG. 1 and 2, the seal structure member 8 has a flat shape with respect to the BJ1 opening end face, but as shown in FIG. 3, the opening end 8a of the opening is tapered toward the inside of the constant velocity universal joint. It is possible to further improve the lubricant outflow prevention effect by using a shape, a circular arc shape, or a shape in which the opening end portion 8b of the opening is provided with a return on the inner side of the constant velocity universal joint as shown in FIG. Is possible.

  FIG. 5 is a view showing another example of the embodiment of the present invention, and shows a state at an operating angle of 0 ° of TJ11 which is a sliding type constant velocity universal joint to which a seal structure member 18 is applied instead of a conventional boot. It is. FIG. 6 is a view showing a state in which the TJ 11 to which the seal structure member 18 is applied is operated.

  7 and 8 are diagrams showing another example of the embodiment of the present invention, and are diagrams showing an example of filling the foamed solid lubricant 7 and the auxiliary lubricating grease 9. When it is necessary to enclose a large amount of lubricant in applications that require maintenance-free use for a long period of time or applications that consume a large amount of lubricant under severe conditions such as high temperature, high speed, and high load, etc., FIG. As shown in FIG. 2, the auxiliary lubricating grease 9 is sealed at the bottom of the outer member, the foamed solid lubricant 7 is sealed around the torque transmitting member 4, and the auxiliary lubricating grease 9 and the foamed solid lubricant 7 are fixed to the constant velocity universal joint. It can coexist on the entire interior space. In addition, in the case where it is possible to perform maintenance in a relatively short period of time or when it is not necessary to enclose the foamed solid lubricant 7 in the entire space inside the constant velocity universal joint, the shape in which the foamed solid lubricant 7 is encapsulated can be maintained. As shown in FIG. 8, a necessary amount of auxiliary lubricating grease 9 and foamed solid lubricant 7 are allowed to coexist in the space around the torque transmission member 4 inside the constant velocity universal joint to provide lubrication for the sliding portion. Can do.

  By using a foamed solid lubricant, it is possible to maintain performance compared to grease etc. even in an environment where impurities such as water and dust enter from the opening, but impurities that impede lubrication do not enter. Suitable for use in relatively few environments. For example, the constant velocity universal joint of the present invention can be suitably used for office equipment used indoors.

  FIGS. 9-12 is a figure which shows the other example of embodiment of this invention, and illustrates the example which used the rubber-like elastic material for the seal structure member 8. FIG. The seal structure member 8 shown in FIGS. 9 and 10 does not interfere with the shaft 6 or the like in the state where the operating angle is 0 ° (FIG. 9), but in the state where the maximum operating angle is obtained when the constant velocity universal joint 1 is used. 6 and the cage 5 are in contact with the outer diameter portion (FIG. 10). By using a rubber-like elastic material for the seal structure member 8, as shown in FIG. 10, the seal structure member 8 can be deformed at the time of contact with a joint constituent member such as a shaft, and can be allowed to interfere with the joint constituent member. For this reason, the diameter D2 of the opening part of the seal structure member 8 and the shape of the opening part can be made narrower than when avoiding interference with the joint constituent member, and the sealing performance can be improved.

  The seal structure member 8 shown in FIGS. 11 and 12 has a shape that is not fixed to the shaft 6 in a state where the operating angle is 0 °, and is in a state where the maximum operating angle is obtained when the constant velocity universal joint 1 is used. This is a shape in which the seal structural member 8 is applied to the cage 5. With this shape, the sealing performance can be further improved as compared with the shapes shown in FIGS. 9 and 10. Further, in FIG. 11, since the seal structure member 8 is not fixed on the shaft 6 side, as shown in FIG. 12, the seal structure member 8 has a partially open shape during operation, and has a cooling performance higher than that of a conventional boot having a sealed shape. Excellent.

  By adjusting the shape of the seal structure member 8 according to the use conditions and use environment of the constant velocity universal joint 1, the lubricant outflow prevention effect, the cooling effect, the impurity intrusion prevention effect, and the durability of the seal structure member due to interference Can control the balance.

  Examples of using the constant velocity universal joint of the present invention for a fixed type constant velocity universal joint include the above-mentioned BJ, undercut free joint (hereinafter referred to as UJ), and the like. The number of balls of such BJ and UJ may be 6 or 8. When a foamed solid lubricant is sealed in BJ or UJ, the lubricant is filled only in the necessary parts, which contributes to cost reduction and weight reduction, and because the operating angle used is large, it is compressed.・ It is easy to bend and the lubricant is easily supplied to the sliding part. On the other hand, examples used for the sliding type constant velocity universal joint include the above-described TJ, double offset joint, cross groove joint, and the like.

  In the constant velocity universal joint of the present invention, the lubricating component is occluded in the resin of the encapsulated foamed solid lubricant, so that the lubricant is applied by deformation due to external force such as compression, expansion, bending, and twisting due to the flexibility of the resin. It can be exuded and gradually released from between the molecules of the resin. At this time, the amount of lubricant that oozes out can be minimized by changing the degree of elastic deformation according to the magnitude of the external force by selecting the resin. Note that the fact that the lubricating component is occluded in the foamed / cured resin means that the liquid / semi-solid lubricating component such as lubricating oil and grease described below does not react with the foamed / cured resin or curing agent, and the compound It means that it is included without becoming.

  The foamed solid lubricant used in the present invention requires very little energy when bent compared to a non-foamed body, and can be flexibly deformed while retaining a lubricating component such as lubricating oil at a high density. Therefore, even if the foamed solid lubricant shrinks in the process of cooling after solidifying the foamed solid lubricant inside the constant velocity universal joint, even if the torque transmission member (steel ball etc.) of the constant velocity universal joint is embraced Since the energy required at the time of bending / deformation is small, it can be easily deformed, and the problem of increased rotational torque can be prevented. Moreover, since it has many foamed parts, ie, a porous part, it is advantageous also at the point of weight reduction. In addition, since the foamed solid lubricant used in the present invention only foams and cures a mixture containing a lubricating component and a resin component, no special equipment is required, and it can be filled and molded in any place. Is possible. Further, the density of the foamed solid lubricant can be changed by controlling the blending amount of the blending components of the mixture.

  As the resin (resin component) that forms a foamed solid lubricant in the present invention and is made porous by curing and foaming, a resin having a rubber-like elasticity after foaming and curing and having a leaching property of the lubricating component by deformation is preferable. . Foaming / curing may be in a form in which foaming / curing is performed when the resin is produced, or in a form in which a foaming agent is blended with the resin and foaming / curing is performed in molding. Here, curing means a cross-linking reaction and / or a phenomenon in which a liquid is solidified. The rubber-like elasticity means rubber elasticity and means that deformation applied by an external force returns to the original shape by eliminating the external force.

  The foaming ratio of the foamed solid lubricant should be 1.1 times or more and less than 100 times. When the expansion ratio is less than 1.1 times, the bubble volume is small and deformation cannot be allowed when external stress is applied. Moreover, when it is 100 times or more, it is difficult to obtain a strength that can withstand external stress. The expansion ratio is preferably 1.1 to 10 times.

  In the present invention, the open cell ratio of the foamed solid lubricant after foaming is 50% or more, preferably 50% or more and 90% or less. When the open cell ratio is less than 50%, the ratio of the resin component (solid component) lubricating oil temporarily taken up into the closed cells increases and may not be supplied to the outside when necessary. If it exceeds 90%, it may be disadvantageous for long-term use due to a decrease in the oil retention of the lubricant and an increase in the amount of lubricant released, or the strength (durability) of the foamed solid lubricant itself may decrease. I get out.

In the present invention, the open cell ratio of the foamed solid lubricant can be calculated by the following procedure.
(1) The foamed solid lubricant that has been foam-cured is cut into an appropriate size to obtain sample A. The weight of sample A is measured.
(2) Soxhlet A is washed for 3 hours (solvent: petroleum benzine). Then leave it in a thermostatic bath at 80 ° C for 2 hours to completely dry the organic solvent and obtain Sample B. The weight of sample B is measured.
(3) The open cell ratio is calculated by the following procedure.
Open cell ratio = (1− (weight of resin component of sample B−weight of resin component of sample A) / weight of lubricating component of sample A) × 100
The resin component weight and the lubrication component weight of Samples A and B are calculated by multiplying the weights of Samples A and B by the composition charge ratio.
Lubricating components taken into discontinuous closed cells are not released to the outside by Soxhlet cleaning for 3 hours, so the weight of sample B is not reduced. The open cell ratio can be calculated as the release of the lubricating component.

  In the present invention, the resin component used for the foamed solid lubricant is preferably a urethane prepolymer that has excellent heat resistance and flexibility and enables cost reduction. This foamed solid lubricant is a solid material in which the urethane prepolymer is made porous by foaming and curing, and a lubricating component is occluded inside the resin. This foamed solid lubricant has excellent lubricating component holding power, and can be manufactured at a low cost while suppressing the amount of the lubricating component oozed out even if it is deformed by an external force.

  The urethane prepolymer that can be used in the present invention is obtained by a reaction between a compound having an active hydrogen group and a polyisocyanate, and the isocyanate group is contained at the end of the molecular chain or at the end of the side chain branched from within the molecular chain. It may be. The urethane prepolymer may have a urethane bond in the molecular chain.

  Depending on the type of monomer (= compound having an active hydrogen group) to be reacted, it is classified into caprolactone, ester and ether. There are Takenate L-1170 (manufactured by Mitsui Chemicals Polyurethanes), L-1158 (manufactured by Mitsui Chemicals Polyurethanes), and Coronate 4090 (manufactured by Nippon Polyurethanes) as ethers. Examples of the ester type include Coronate 4047 (manufactured by Nippon Polyurethane Co., Ltd.), and caprolactone type includes Takenate L-1350 (manufactured by Mitsui Chemicals Polyurethanes), Takenate L-1680 (manufactured by Mitsui Chemicals Polyurethanes), and Sianaprene 7-QM. (Manufactured by Mitsui Chemicals Polyurethane), Plaxel EP1130 (manufactured by Daicel Chemical Industries) and the like.

  Moreover, the oligomer and prepolymer compound which modified the terminal group into the isocyanate group can also be used. Examples of such a compound include a terminal isocyanate-modified polyether polyol and an isocyanate-modified product of a hydroxyl group-terminated polybutadiene. Examples of the terminal isocyanate-modified polyether polyol include Coronate 1050 (manufactured by Nippon Polyurethane Co., Ltd.). Moreover, poly-bd MC50 (made by Idemitsu Kosan Co., Ltd.) and poly-bd HTP9 (made by Idemitsu Kosan Co., Ltd.) are mentioned as the isocyanate modified body of hydroxyl-terminated polybutadiene.

  These urethane prepolymers can be used in combination of two or more depending on the desired mechanical properties.

  In the present invention, it is preferable to use a urethane prepolymer having an isocyanate group content of 2 wt% or more and less than 6 wt%. If the content of isocyanate group (-NCO) is less than 2% by weight, it becomes difficult to achieve both foamability and elasticity, and if it is more than 6% by weight, the hardness becomes too large and the resilience becomes large and deformation due to external force. It becomes easy to generate heat when receiving.

  Moreover, the isocyanate group can use the block isocyanate etc. which blocked the isocyanate group with blocking agents, such as phenols, lactams, alcohols, and oximes.

  The curing agent for curing the urethane prepolymer is preferably a compound having active hydrogen, and examples thereof include a polyamino compound having a functional group as an amino group and a polyol compound having a functional group as a hydroxyl group.

  Polyamino compounds include 3,3'-dichloro-4,4'-diaminodiphenylmethane (hereinafter referred to as MOCA), 3,3'-dimethyl-4,4'-diaminodiphenylmethane, and 3,3'-dimethoxy-4. , 4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, trimethylene-bis- (4-aminobenzoate), bis (methylthio) -2,4- Aromatics typified by toluenediamine, bis (methylthio) -2,6-toluenediamine, methylthiotoluenediamine, 3,5-diethyltoluene-2,4-diamine, 3,5-diethyltoluene-2,6-diamine Examples include polyamino compounds.

  Among the polyamino compounds, aromatic amino compounds are preferable because of low cost and excellent physical properties, and aromatic diamino compounds having a substituent at the position adjacent to the amino group are particularly preferable. In the present invention, it is considered that the reactivity of the amino group is suppressed by the substituent at the adjacent position because it undergoes a step of curing together with foaming.

  When the urethane prepolymer is cured with a polyamino compound, it becomes a foamed solid lubricant having urethane and urea bonds in the molecule. By generating urea bonds, the urethane bond density in the molecule is lowered, and elongation and impact resilience are improved. Moreover, rigidity can be provided by generating a urea bond.

  Examples of the polyol compound include low molecular polyols such as 1,4-butane glycol and trimethylolpropane, polyether polyols, castor oil polyols, and polyester polyols. Of the polyol compounds, trimethylolpropane is preferred.

  The ratio of the isocyanate group (—NCO) contained in the urethane prepolymer and the functional group of the curing agent that reacts with the isocyanate group is an equivalent ratio when the functional group is an amino group or a hydroxyl group (functional group of the curing agent). /NCO)=1/(1.1 to 2.5) is preferable.

The ratio of the isocyanate group contained in the urethane prepolymer, the amino group (—NH ₂ ) or hydroxyl group (—OH) of the curing agent, and the hydroxyl group of water (—OH) as the foaming agent, Flexibility, elasticity, etc. are determined. When the amino group (—NH ₂ ) or hydroxyl group (—OH) of the curing agent is reacted with the isocyanate group (—NCO) of the urethane prepolymer in an equivalent amount, an isocyanate group (—NCO) that reacts with water as the foaming agent is formed. Since it will disappear, the range of (functional group of curing agent / NCO) = 1 / (1.1 to 2.5) is preferable. Moreover, the ratio of the hydroxyl group of water which is a foaming agent and the functional group of a hardening | curing agent is the range of (hydroxyl group of water / functional group of a hardening | curing agent) = 1 / (0.7-2.0) by an equivalent ratio. If the amount of the curing agent is less than the above range, not only the physical properties such as the strength of the foamed solid lubricant are remarkably lowered, but also the urethane elastomer may not be cured.

  Another example of the resin component is polyether polyol. Examples of polyether polyols include low molecular polyol alkylene oxides (C2-C4 alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide) adducts and alkylene oxide ring-opening polymers. Includes polyethylene glycol, polypropylene glycol, and polytetramethylene ether glycol. As an example of polyether polyol, trade name Preminol manufactured by Asahi Glass Co., Ltd. may be mentioned. Preminol is a polyether polyol having a molecular weight of 5000-12000.

  A polyisocyanate is mentioned as a hardening | curing agent which hardens the said polyether polyol. Examples of the polyisocyanate include diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and mixtures thereof, 1,5-naphthylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene. Diisocyanate is mentioned. Examples of commercially available products include Nippon Polyurethane Co., Ltd .: Coronate T80.

  The lubricating component that can be used in the present invention can be used as long as it does not dissolve the solid component forming the foam. As the lubricating component, for example, lubricating oil, grease, wax or the like can be used alone or in combination. Particularly preferred are hydrocarbon-based lubricants, hydrocarbon-based greases, or mixtures of hydrocarbon-based lubricants and hydrocarbon-based greases.

  Examples of the hydrocarbon-based lubricating oil include paraffinic and naphthenic mineral oils, hydrocarbon-based synthetic oils, GTL base oils, and the like. These can be used alone or as a mixed oil. In addition, ester synthetic oils, ether synthetic oils, fluorine oils, silicone oils and the like can also be used. These can be used alone or as a mixed oil.

  The hydrocarbon-based grease is a grease having a hydrocarbon oil as a base oil, and examples of the base oil include the above-described hydrocarbon-based lubricating oil. Examples of the thickener include lithium soaps, lithium complex soaps, calcium soaps, calcium complex soaps, aluminum soaps, aluminum complex soaps, and other urea compounds such as diurea compounds and polyurea compounds. It is not a thing. The diurea compound is obtained by the reaction of diisocyanate and monoamine, and the polyurea compound is obtained by the reaction of diisocyanate and polyamine. In addition, greases based on ester-based synthetic oils, ether-based synthetic oils, GTL base oils, fluorine oils, silicone oils and the like can also be used.

  As the lubricating component, hydrocarbon synthetic wax, polyethylene wax, higher fatty acid ester wax, higher fatty acid amide wax, ketone / amines, hydrogenated oil, and the like can be mixed and used.

  In the present invention, the means for foaming the foamed solid lubricant (foaming agent) uses an isocyanate compound as a raw material, and therefore preferably uses water that reacts with the isocyanate compound to generate carbon dioxide gas.

  Moreover, it is preferable to use a catalyst as needed, 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. Examples of organometallic catalysts include stanaoctate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutyltin maleate, dioctyltin dimercaptide, dioctyltin thiocarboxylate, octenoate, etc. Is mentioned. Moreover, you may mix and use these multiple types for the purpose of adjusting the balance of reaction.

  In the present invention, the foamed solid lubricant is obtained by foaming and curing a mixture containing the lubricating component, a resin component such as the urethane prepolymer or the polyether polyol, a curing agent, and a foaming agent.

  When the resin component is a urethane prepolymer, the blending ratio of the lubricating component is 20 to 80% by weight, preferably 40 to 60% by weight, based on the entire mixture. If the lubricating component is less than 20% by weight, the supply amount of lubricating oil or the like is so small that it cannot function as a foamed solid lubricant, and if it is more than 80% by weight, it may not solidify.

  When the resin component is a polyether polyol, the blending ratio of the lubricating component is 60 to 80% by weight with respect to the entire mixture. If the lubricating component is less than 60% by weight, the supply amount of lubricating oil or the like is so small that it cannot function as a foamed solid lubricant, and if it is more than 80% by weight, it may not solidify.

  In the present invention, various additives such as pigments, antistatic agents, flame retardants, antifungal agents and fillers can be added to the foamed solid lubricant as necessary. In addition, solid lubricants such as molybdenum disulfide and graphite, friction modifiers such as organic molybdenum, oily agents such as amines, fatty acids and oils, antioxidants such as amines and phenols, petroleum sulfonates, dinonylnaphthalene sulfate Rust inhibitors such as phonates and sorbitan esters, extreme pressure agents such as sulfur and sulfur-phosphorus, antiwear agents such as organic zinc and phosphorus, metal deactivators such as benzotriazole and sodium nitrite, polymethacrylate, Various additives such as a viscosity index improver such as polystyrene may be included.

  The method of mixing each component when producing the foamed solid lubricant is not particularly limited, and for example, mixing is performed using a commonly used stirrer such as a Henschel mixer, a ribbon mixer, a juicer mixer, a mixing head, or the like. can do.

  The mixture preferably uses a surfactant such as a commercially available silicone foam stabilizer, and each raw material molecule is preferably dispersed uniformly. Further, the surface tension can be controlled by the type of the foam stabilizer, and the type of the generated bubbles can be controlled to open cells or closed cells. Examples of such surfactants include anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, silicone surfactants, and fluorine surfactants.

  In the present invention, using a reactive impregnation method in which a foaming reaction and a curing reaction are simultaneously performed in the presence of a lubricating component such as a lubricating oil, in order to simultaneously achieve a high filling of the lubricating component and a high elongation of material properties at the same time. desirable. This is because the bubbles formed in the foam in the foam formation stage are uniformly impregnated with the lubrication component, and the lubrication component is occluded in the foamed / cured resin to increase the filling of the lubrication component and improve the material properties. High elongation is considered to be compatible. In contrast, the post-impregnation method in which a foam is manufactured in advance and impregnated with a lubricating component does not have sufficient lubricating component holding power. Supply shortage.

  The foamed solid lubricant may be foamed and cured after pouring a mixture containing the lubricating component and resin into the constant velocity universal joint, and after foaming and curing at normal pressure, it can be cut and ground to the desired shape. It can be post-processed and incorporated into a constant velocity universal joint. In the present invention, it is possible to easily fill any part in a constant velocity universal joint having a complicated shape, and a molding die or a grinding process for obtaining a foam molded article is unnecessary. It is preferable to employ a method in which the mixture is poured into a constant velocity universal joint before foaming / curing and foamed / cured in the joint. By adopting this method, the manufacturing process is simplified and the cost can be reduced.

  When the mixture is poured into the constant velocity universal joint before foaming / curing, either a method of mounting the seal structure member in advance before pouring the mixture or a method of mounting after foaming / curing is adopted. Good. When the seal structure member is mounted in advance, the mixture is poured from the gap between the seal structure member and the shaft.

  In the constant velocity universal joint of the present invention, as the thickener and base oil of the auxiliary lubricating grease that can coexist with the foamed solid lubricant, those exemplified as an example of the lubricating component in the foamed solid lubricant may be used. it can. Similarly, various additives can be included.

  In the present invention, by adding wax to the grease for auxiliary lubrication, the fluidity can be suppressed at a relatively low temperature (ordinary temperature) and the lubrication can be maintained at the site where lubrication is required. As the wax rises, the wax melts, so that the fluidity of the auxiliary lubricating grease improves, and the lubricant is quickly supplied to the place where the lubricant is required.

  The wax used for the auxiliary lubricating grease has a melting point in the range of 70 to 150 ° C. If the melting point is less than 70 ° C, the softening (flowing) temperature is low, so it may flow more than necessary and the lubricant may move from where it is needed. . When the temperature exceeds 150 ° C., the melting point is too high and the wax may not melt when necessary, and the target fluidity may not be lowered, and the supply of the lubricating component to the sliding portion may be delayed. Further, when the melting point of the wax is high, it is necessary to raise the auxiliary lubricating grease to a high temperature when the wax is melted and dispersed, which causes a deterioration of the auxiliary lubricating grease itself.

  The wax used for the auxiliary lubricating grease is preferably selected from at least one of fatty acid amide and hydrogenated oil. The fatty acid amide may be a saturated fatty acid amide or an unsaturated fatty acid amide. Preferable fatty acid amides include stearic acid amide, oleic acid amide, erucic acid amide, and ethylenebisstearic acid amide. Examples of hydrogenated oil include hardened castor oil.

  The amount of wax added to the auxiliary lubricating grease is 1% by weight or more and less than 15% by weight, more preferably 2 to 10% by weight, based on the entire auxiliary lubricating grease. If the amount is less than 1% by weight, the increase in fluidity near the target normal temperature cannot be obtained, so that there is no effect of adding wax. If it is 15% by weight or more, the auxiliary lubricating grease becomes too hard and it is difficult to supply it to a place where lubrication is required, which is not preferable. When these waxes are added to the auxiliary lubricating grease, it is preferable that the auxiliary lubricating grease be heated and mixed uniformly over the melting point of the selected wax.

  The amount of auxiliary lubricating grease to be enclosed in the constant velocity universal joint is preferably 1 to 60% by volume of the space volume inside the constant velocity universal joint. More preferably, it is 3 to 40% by volume. If the amount is too small, the amount of lubricant used as auxiliary lubrication is insufficient, and if the amount is too large, the amount of the foamed solid lubricant that contributes to lubrication over a long period of time decreases, resulting in a problem in durability.

  The place where the auxiliary lubricating grease is enclosed or applied is not particularly limited as long as it can reach the rolling part and the sliding part in the joint at the start of the constant velocity universal joint. Preferably, it is the vicinity of the sliding part and rolling part in a universal joint. Specific parts of the constant velocity universal joint include the outer member bottom (see FIG. 1 and the like), the inner member near the shaft, the track portion near the torque transmission member, the cage inner and outer surfaces, and the cage window. The spherical portion of the outer member-cage-inner member can be mentioned.

  There is no limitation on the method of enclosing auxiliary lubricating grease in the constant velocity universal joint. Before filling the constant velocity universal joint with the solid foamed lubricant, auxiliary lubrication grease may be sealed or applied in the constant velocity universal joint or its parts, or the constant velocity universal joint is filled with the solid foam lubricant. Then, it may be injected into a target site with a syringe (or similar one).

<Preparation of auxiliary lubricating grease>
Auxiliary lubricating grease A to auxiliary lubricating grease H used in Examples 1 to 8 were prepared by the following method.

Auxiliary lubrication grease A
Base grease by uniformly dispersing 9.16 g of diphenylmethane-4,4-diisocyanate and 7.84 g of p-toluidine in 83 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100) Got. To this base grease, 10% by weight of stearamide (manufactured by Kao Corporation: fatty acid amide T melting point 97 to 102 ° C.) was added, heated to 110 ° C. and stirred well to obtain auxiliary lubricating grease A.

Auxiliary lubrication grease B
Base grease by uniformly dispersing 9.16 g of diphenylmethane-4,4-diisocyanate and 7.84 g of p-toluidine in 83 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100) Got. To this base grease, 3% by weight of stearamide (manufactured by Kao Corporation: fatty acid amide T melting point 97-102 ° C.) was added, heated to 110 ° C. and stirred well to obtain auxiliary lubricating grease B.

Auxiliary lubrication grease C
Base grease by uniformly dispersing 9.16 g of diphenylmethane-4,4-diisocyanate and 7.84 g of p-toluidine in 83 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100) Got. To this base grease, 5% by weight of ethylene bis-stearic acid amide (manufactured by Kao Corporation: fatty acid amide EB-G melting point 141.5-146.5 ° C) was added, heated to 150 ° C, stirred well, and supplementary lubricating grease C Got.

Auxiliary lubrication grease D
In 92 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100), 3.94 g of diphenylmethane-4,4-diisocyanate and 4.07 g of octylamine were reacted, and the resulting diurea compound was uniformly dispersed to form a base grease. Obtained. To this base grease, 5% by weight of erucic acid amide (manufactured by Kao Corporation: fatty acid amide E melting point 79-85 ° C.) was added, heated to 100 ° C. and stirred well to obtain auxiliary lubricating grease D.

Auxiliary lubrication grease E
In 92 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100), 3.94 g of diphenylmethane-4,4-diisocyanate and 4.07 g of octylamine were reacted, and the resulting diurea compound was uniformly dispersed to form a base grease. Obtained. To this base grease, 5% by weight of oleic acid amide (manufactured by Kao Corporation: fatty acid amide O—N melting point: 70 to 75 ° C.) was added, heated to 100 ° C. and stirred well to obtain auxiliary lubricating grease E. It was.

Auxiliary lubrication grease F
In 92 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100), 3.94 g of diphenylmethane-4,4-diisocyanate and 4.07 g of octylamine were reacted, and the resulting diurea compound was uniformly dispersed to form a base grease. Obtained. To this base grease, 5% by weight of hardened castor oil (manufactured by Kao Corporation: Kao wax 85-P melting point 85-87 ° C.) was added, heated to 100 ° C. and stirred well to obtain auxiliary lubricating grease F. .

Auxiliary lubrication grease G
Base grease by uniformly dispersing 9.16 g of diphenylmethane-4,4-diisocyanate and 7.84 g of p-toluidine in 83 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100) Got. To this base grease, 5% by weight of paraffin wax (manufactured by Nippon Seiwa Co., Ltd .: HNP-5 melting point 62 ° C.) was added, heated to 80 ° C. and stirred well to obtain auxiliary lubricating grease G.

Auxiliary lubrication grease H
Base grease by uniformly dispersing 9.16 g of diphenylmethane-4,4-diisocyanate and 7.84 g of p-toluidine in 83 g of mineral oil (manufactured by Nippon Oil Corporation: Turbine 100) Got. To this base grease, 15% by weight of stearamide (manufactured by Kao Corporation: fatty acid amide T melting point 97-102 ° C.) was added, heated to 110 ° C., and stirred well to obtain auxiliary lubricating grease H.

Examples 1 to 6
First, as shown in FIG. 1, an outer member 2, an inner member 3, a cage 5 and a steel ball 4 which is a torque transmission member are assembled into a fixed eight ball joint sub-assembly (NTN: EBJ82 outer diameter size 72.6 mm), the auxiliary lubricating grease shown in Table 1 was sealed at the bottom of the outer member 2. Next, among the compositions shown in Table 1, (a), (d), (e), (i) were mixed well at 80 ° C., and then dissolved at 120 ° C. (b), (h) were added. Mix quickly. Finally, after (c) was added and stirred, 18.0 g was sealed in the joint in which auxiliary lubricating grease 9 was sealed. After a few seconds, the foaming reaction started, and the foamed solid lubricant 7 in the joint was cured by leaving it at 100 ° C. for 30 minutes. 1 was assembled, and other members such as the shaft 6 were assembled to obtain a constant velocity universal joint in which the foamed solid lubricant 7 and the auxiliary lubricating grease 9 coexisted. The seal structure member 8 was attached to the outer diameter surface of the outer member 2 with a left and right crimped band 10. In addition, the open cell ratio of the foamed solid lubricant in Table 1 was measured based on the above-described method for calculating the open cell ratio. For the foamed solid lubricant, the equivalent ratio of the curing agent and NCO and the equivalent ratio of water and the curing agent were also measured. These results are also shown in Table 1.

Example 7 and Example 8
First, as shown in FIG. 1, an outer member 2, an inner member 3, a cage 5 and a steel ball 4 which is a torque transmission member are assembled into a fixed eight ball joint sub-assembly (NTN: EBJ82 outer diameter size 72.6 mm), the auxiliary lubricating grease shown in Table 1 was sealed at the bottom of the outer member 2. (D), (i), (h) and (c) were added to (g) with the component amounts (composition) shown in Table 1, and the mixture was heated at 90 ° C. and stirred well. After adding (f) to this and stirring well, 16.0 g was sealed in the above-mentioned joint subassembly in which the auxiliary lubricating grease 9 was sealed. After a few seconds, the foaming reaction started, and the foamed solid lubricant 7 in the joint was cured by leaving it in a constant temperature bath set at 90 ° C. for 15 minutes. 1 was assembled, and other members such as the shaft 6 were assembled to obtain a constant velocity universal joint in which the foamed solid lubricant 7 and the auxiliary lubricating grease 9 coexisted. The seal structure member 8 was attached to the outer diameter surface of the outer member 2 with a left and right crimped band 10. In addition, the open cell ratio of the foamed solid lubricant in Table 1 was measured based on the above-described method for calculating the open cell ratio. The results are also shown in Table 1.

  In the constant velocity universal joint of the present invention, a predetermined foamed solid lubricant and auxiliary lubricating grease coexist in the inside, and a predetermined seal structure member is provided. Therefore, even when used at a high operating angle, the constant velocity universal joint has a long period of time. Lubricating performance can be maintained and the cost is low. For this reason, it can utilize suitably as a constant velocity universal joint used for a motor vehicle, an industrial machine, office equipment, etc.

1, 21 Constant velocity universal joint (BJ)
2,22 Outer member (outer ring)
3, 23 Inner member (inner ring)
4, 24 Torque transmission member 5, 25 Cage 6, 26 Shaft 7, 17 Foamed solid lubricant 7a Coating 8, 18 Seal structure member 9, 19 Grease for auxiliary lubrication 10 Left and right caulking band 11, 31 Constant velocity universal joint ( TJ)
12, 32 Outer member (outer ring)
13, 33 Tripod member 14, 34 Spherical roller (torque transmission member)
15, 35 Needle 16, 36 Shaft 20 One-touch type band 29, 39 Grease 30, 40 Boot 30a, 30b Left and right caulking type band 40a, 40b One-touch type band

Claims (16)

An outer member, a track groove provided on an inner diameter surface of the outer member, a torque transmission member that rolls along the track groove, a shaft that transmits rotational torque to the torque transmission member, and the outer side A constant velocity universal joint comprising a seal structure member covering the opening side end surface of the member, and having no boots,
The seal structure member has an opening through which the shaft passes,
The constant velocity universal joint is for auxiliary lubrication containing at least a foamed solid lubricant containing a lubricating component in a resin that is foamed and cured to be porous, and a wax having a melting point of 70 to 150 ° C. Constant velocity universal joint characterized by the coexistence of grease.   2. The opening of the seal structure member has a shape such that the seal structure member does not interfere with a joint component member including the shaft and the torque transmission member when the constant velocity universal joint is operated. The constant velocity universal joint described.   The opening of the seal structure member has a circular cross section in the axial direction concentric with the shaft, and the diameter of the opening is at the maximum operating angle of the constant velocity universal joint. The constant velocity universal joint according to claim 2, wherein the length is such that the members do not contact each other.   The seal structure member is made of a rubber-like elastic material, and has a shape that interferes with the cage, the inner member, the shaft, or the torque transmission member of the constant velocity universal joint when the constant velocity universal joint is operated. The constant velocity universal joint according to claim 1.   5. The constant velocity universal joint according to claim 4, wherein the seal structure member has a shape that contacts the shaft without being fixed to the constant velocity universal joint at an operating angle of 0 °.   The constant velocity universal joint according to any one of claims 1 to 5, wherein the seal structure member is attached to an outer diameter portion of the outer member by a band, press-fitting, or bonding.   The constant velocity universal joint according to any one of claims 1 to 6, wherein the constant velocity universal joint is used for equipment used indoors.   The constant velocity universal joint according to any one of claims 1 to 7, wherein the wax is at least one selected from a fatty acid amide and hydrogenated oil.   The foamed solid lubricant is characterized in that the resin that is foamed and cured to become porous has rubber-like elasticity, and the lubricating component contained in the resin has exudability due to deformation of the rubber-like elastic body. The constant velocity universal joint according to any one of claims 1 to 8.   The constant velocity universal joint according to any one of claims 1 to 9, wherein an open cell ratio after foaming / curing of the foamed / cured resin to be porous is 50% or more. The foamed solid lubricant is obtained by foaming and curing a mixture containing the lubricating component, the resin, a curing agent, and a foaming agent.
The resin is a urethane prepolymer containing 2 wt% or more and less than 6 wt% of isocyanate groups in the molecule;
The blowing agent is water;
The constant velocity universal joint according to any one of claims 1 to 10, wherein the mixture contains 20 to 80% by weight of the lubricating component with respect to the entire mixture.   The constant velocity universal joint according to claim 11, wherein the urethane prepolymer is at least one urethane prepolymer selected from an ester urethane prepolymer, a caprolactone urethane prepolymer, and an ether urethane prepolymer. .   The ratio of the isocyanate group and the functional group of the curing agent that reacts with the isocyanate group is an equivalent ratio (functional group of the curing agent / NCO) = 1 / (1.1 to 2.5). The constant velocity universal joint according to claim 11 or 12.   12. The ratio of the hydroxyl group of water and the functional group of the curing agent is an equivalent ratio (water hydroxyl group / functional group of the curing agent) = 1 / (0.7 to 2.0). The constant velocity universal joint according to claim 12 or claim 13.   The constant velocity universal joint according to any one of claims 11 to 14, wherein the curing agent is an aromatic polyamino compound.   16. The constant velocity universal joint according to claim 15, wherein the aromatic polyamino compound is an aromatic polyamino compound having a substituent at a position adjacent to an amino group.

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