JP4436302B2 - Spherical roller bearing and manufacturing method thereof - Google Patents

Description

The present invention relates to a self-aligning roller bearing filled with a lubricant-containing polymer and a method for manufacturing the same .

  Conventionally, as a self-aligning roller bearing, there is one filled with a lubricant-containing polymer (for example, see Patent Document 1). This self-aligning roller bearing has an inner ring 1 and an outer ring 2 as shown in FIG. The inner ring 1 is formed with two rows of tracks 1a, a drop-off preventing collar 1b is provided at the outer end portion of each track 1a, and a guide collar 1c is provided at a portion between the tracks 1a. The outer ring 2 is formed with tracks 2 a that face the tracks 1 a of the inner ring 1. Two rows of rollers 3 are arranged between the raceway 1a of the inner ring 1 and the raceway 2a of the outer ring 2, and the rollers 3 in each row are held by corresponding cages 4, respectively. Each cage 4 is composed of a separation type cage that holds the roller 3 for each row of the rollers 3. Plastic grease (lubricant-containing polymer) 5 is placed in the space between the inner ring 1 and the outer ring 2 and in the gap between each drop prevention collar 1b of the inner ring 1 and the outer end surface of each row 3 of rollers 3. With the plastic grease 5 filled and filled in the gap between each fall-off prevention collar 1b of the inner ring 1 and the outer end face of each row of rollers 3, the inner end face of each row of rollers 3 corresponds to the guide collar 1c. Each side is held in contact with each other.

In this plastic grease filling method, two encapsulated firing templates having a flange fitted to the outer peripheral surface of the outer ring 2 and provided with a rib for pressing the outer end surface of the roller 3 on the inner surface thereof are used. After putting an unfired raw material of plastic grease into the space between the inner ring 1 and the outer ring 2, each encapsulated firing template is fitted into each end face of the inner ring 1 and the outer ring 2, and the ribs of each encapsulated firing template are used. A method is used in which an unfired raw material of plastic grease is fired in a state where the outer end surfaces of the rollers 3 in each row are pressed so that the inner end surfaces of the rollers 3 in each row are in contact with the corresponding side surfaces of the guide collar 1c. .
JP-A-6-50330

  However, in the conventional self-aligning roller bearing described above, the inner end face of each row of rollers 3 and each side face of the guide collar 1c are in contact with each other, so that the lubrication state between them may not be sufficient in some cases. There is sex. In this case, there is a possibility that the generated torque will increase and the temperature rise will increase with the rotation of the bearing. Therefore, when the temperature rise becomes large, the lubricant-containing polymer 5 may be softened and the mechanical strength of the lubricant-containing polymer 5 may be reduced. The lubricant-containing polymer has a property that the higher the temperature, the faster the release rate of the contained lubricant, and the releasable lubricant may be released in a shorter time.

  In addition, the separation-type cage separated so as to correspond to each row of the rollers 3 is used as the cage 4, whereas the lubricant-containing polymer 5 is integrated so as to include each row of the rollers 3. Since it is solidified, lubrication is caused by the difference in the movement of the rollers 3 in each row under the use conditions in which each row of rollers 3 moves differently for each row together with the cage 4, for example, under high-speed and high-load use conditions. There is a possibility that a shearing force acts on the agent-containing polymer 5 and an excessive force is applied to the lubricant-containing polymer 5 at a position near the middle of each row.

SUMMARY OF THE INVENTION An object of the present invention is to provide a self-aligning roller bearing capable of preventing the possibility of an excessive temperature rise and improving the reliability with respect to use conditions of high speed and high load, and a method for manufacturing the same. There is to do.

In order to achieve the above object, the present invention provides an inner ring having two rows of raceways, an outer ring having a drop-off preventing collar at the outer end of each raceway, and an outer ring having a raceway facing each raceway of the inner race, Two rows of rollers disposed between each race of the inner ring and the race of the outer ring, a cage that holds the rollers of each row, and each row of rollers between the cage and the inner race and a guide wheel which is arranged so as to guide the rollers, together constitute a one-piece with the retainer, in the space between the inner ring and the outer ring, before Symbol the inner end face of the roller in each row and the guide wheel a gap, and the method of manufacturing a self-aligning roller bearing filled with lubricant-containing polymer into the gap between the falling-off preventing flange of the outer end face the inner ring of the roller in each row between the end face of the inner ring Opposite recesses for receiving and outer end surfaces of the rollers in each row, and projecting vertically from the inner surface A filling jig formed with an annular convex portion provided with a plurality of projections in the shape is fitted into the self-aligning roller bearing, the concave portion accepts an end surface of the inner ring, and an outer end surface of the roller in each row And a gap between the inner ring and the collar for preventing the inner ring from falling off, and a gap for filling the lubricant-containing polymer is generated, and the plurality of protrusions abut against the retainer and the guide ring, and Between the inner end face of each row of rollers and the guide ring, a gap for filling the lubricant-containing polymer is generated, and the lubricant-containing polymer is a polyolefin-based polymer with respect to the total weight. Composition ratio of 10-50% by weight of resin, 90-50% by weight of lubricant, 0-5% by weight classified as wax, 8-48% by weight of relatively low molecular weight, ultra high molecular weight 2-10% by weight, this A lubricant-containing polymer having a composition ratio of polyolefin resin having a total of three resin components of 10 to 50% by weight and a polymer hardness [HDA] (durometer A scale hardness) in the range of 80 to 90, Filling the generated gap between the inner end face of each row of rollers and the guide ring and the gap between the outer end face of each row of rollers and the collar to prevent the inner ring from falling off. A method for manufacturing a spherical roller bearing is provided.

  This lubricant-containing polymer is a synthetic resin selected from the group of polyolefin resins having basically the same chemical structure, such as polyethylene, polypropylene, polybutylene, polymethylpentene, and the like. Paraffin hydrocarbon oil such as naphthenic hydrocarbon oil, mineral oil, ether oil such as dialkyldiphenyl ether oil, ester oil such as phthalate ester, etc. Is plasticized by heating above the melting point of the synthetic resin, and then cooled to solid form. It is also possible to use a lubricant to which various additives such as an antioxidant, a rust inhibitor, an antiwear agent, a foam remover, and an extreme pressure agent are added in advance.

  The composition ratio of the lubricant-containing polymer is 10 to 50% by weight of the polyolefin resin and 90 to 50% by weight of the lubricant with respect to the total weight. When the composition ratio of the lubricant-containing polymer 8 is less than 10% by weight of the polyolefin-based resin, the hardness / strength exceeding the predetermined level cannot be obtained, and the lubricant-containing polymer is subjected to a load due to rotation of the bearing or the like. Sometimes, it is difficult to maintain the initial shape of the lubricant-containing polymer, and there is a high possibility that the lubricant-containing polymer will drop out of the internal space of the bearing. Further, when the polyolefin-based resin exceeds 50% by weight in the composition ratio of the lubricant-containing polymer (that is, when the lubricant is less than 50% by weight), the amount of lubricant supplied to the bearing is reduced, and the bearing life is reduced. I cannot expect the extension.

The group of polyolefin resins has the same basic structure but different average molecular weight, and the average molecular weight ranges from 700 to 5 × 10 ⁶ . Selected synthetic resin from this group are those with an average molecular weight is classified into wax in the range of from 700 to 1 × 10 ⁴ (e.g., polyethylene wax), an average molecular weight of 1 × 10 ⁴ ~1 × 10 ⁶ Of a relatively low molecular weight in the range of 1 and an ultra-high molecular weight in the range of 1 × 10 ^{6 to} 5 × 10 ⁶ in average molecular weight, or a single material or a mixture thereof. . A combination of a relatively low molecular weight material and a lubricant provides a lubricant-containing polymer having a certain degree of mechanical strength, lubricant supply capability, and oil retention. In this combination, when a part of the relatively low molecular weight is replaced with one classified as wax, the difference in molecular weight between the one classified as wax and the lubricant is small, so the affinity with the lubricant is high. As a result, the oil retaining property of the lubricant-containing polymer is improved and the lubricant can be supplied over a long period of time, but the mechanical strength is lowered. The waxes that can be used here are not only polyolefin resins such as polyethylene wax, but also hydrocarbon resins having a melting point in the range of 373 to 403 K (100 to 130 ° C.) or higher (for example, paraffin). System synthetic wax). On the other hand, if a part of the relatively low molecular weight is replaced with an ultra high molecular weight, the difference in molecular weight between the ultra high molecular weight and the lubricant is large, so the affinity with the lubricant is reduced, As a result, the oil retention of the lubricant-containing polymer is reduced, and the release rate of the lubricant from the lubricant-containing polymer is increased. As a result, the period until the amount of lubricant that can be supplied from the lubricant-containing polymer is shortened, and the bearing life cannot be extended. However, the mechanical strength is improved.

  When polymethylpentene is used alone, it is difficult to obtain a predetermined hardness when trying to increase the amount of lubricant contained, and high-density polyethylene, super It is necessary to add polyethylene such as high molecular weight polyethylene. The ratio of polymethylpentene and polyethylene is suitably polymethylpentene: polyethylene = 4: 6 to 9: 1 (preferably 6: 4 to 8: 2). When the amount of polyethylene is larger than the ratio of 4: 6, the softening temperature is lowered, the maximum number of rotations used is almost the same as that of polyethylene alone, and when the amount of polymethylpentene is larger than the ratio of 9: 1. It becomes difficult to obtain a hardness (65HDA) of a predetermined level or higher. Moreover, it is necessary to make it 503-523K (230-250 degreeC) at the time of melting polymethylpentene, and since mineral oil, poly alpha-olefin oil, etc. volatilize a considerable amount at the said temperature, it is not suitable, heat-resistant In view of compatibility and compatibility with polymethylpentene, alkyl polyphenyl ethers such as dialkyl diphenyl ethers are preferred.

  Considering the balance of moldability, mechanical strength, oil retention, and lubricant supply amount, the composition ratio of the lubricant-containing polymer is 0 to 5% by weight classified as wax, and 8 to 48 having a relatively low molecular weight. It is preferable to use 2 to 10% by weight, 2 to 10% by weight of ultra high molecular weight, and 10 to 50% by weight of the total of these three resins (the remainder being 90 to 50% by weight of lubricant).

  One of the mechanical strengths of the lubricant-containing polymer is the hardness [HDA] of the lubricant-containing polymer, and the hardness [HDA] is preferably in the range of 65 to 90, more preferably 70 to It is in the range of 85. When this hardness [HDA] is less than 65, it is weak in strength and may be damaged by rotation of the bearing. On the other hand, when the hardness [HDA] exceeds 90, the force for restraining the roller is large, and this restraining force increases the torque of the bearing and increases the amount of heat generated by the rotation of the bearing, thereby increasing the temperature of the bearing. There is a fear.

  In order to improve the mechanical strength of the lubricant-containing polymer, a material obtained by adding the following thermoplastic resin and thermosetting resin to the above-described polyolefin resin can be used.

  As the thermoplastic resin, resins such as polyamide, polycarbonate, polybutylene terephthalate, polyphenylene sulfide, polyethersulfone, polyetheretherketone, polyamideimide, polystyrene, and ABS resin can be used. As the thermosetting resin, each resin such as unsaturated polyester resin, urea resin, melanin resin, phenol resin, polyimide resin, and epoxy resin can be used. These resins may be used alone or in combination. Furthermore, in order to disperse the polyolefin resin and other resins in a more uniform state, an appropriate compatibilizing agent may be added as necessary.

  Further, a filler may be added to improve mechanical strength. Examples of the filler include inorganic whiskers such as calcium carbonate, magnesium carbonate, potassium titanate whisker and aluminum borate whisker, or glass. There are inorganic fibers such as fibers and metal fibers, and those obtained by braiding these into a cloth shape. In addition, as an organic compound, carbon black, graphite powder, carbon fibers, aramid fibers, polyester fibers, or the like may be added.

  Furthermore, anti-aging agents such as N, N'-diphenyl-P-phenyldiamine and 2,2'-methylenebis (4-ethyl-6-t-butyphenol) are used for the purpose of preventing thermal degradation of polyolefin resins. And 2-hydroxy-4-n-octoxybenzophenone, 2- (2′-hydroxy-3′-t-butyl-5′-methyl-phenyl) -5-chloro for the purpose of preventing deterioration due to light. An ultraviolet absorber such as benzotriazole may be added.

  The addition amount of all the above additives (other than polyolefin resin + lubricant) is preferably 20% by weight or less of the total amount of the molding raw material in order to maintain the supply capability of the lubricant.

  As a method for filling the lubricant-containing polymer, a method using a filling jig and a method for filling the lubricant-containing polymer with the bearing supported so that the rotation axis is parallel to a horizontal support surface, firing and solidifying the polymer are performed. There is a method. Note that these methods will be described in detail in an embodiment described later.

  According to the present invention, since the cage is configured as an integral type, the movement of the rollers in each row is constrained by the cage, and the rollers in each row together with the cage for each row under high-speed and high-load use conditions. The lubricant does not move differently, and even when the lubricant-containing polymer is filled between the rows of rollers, no shear force acts on the lubricant-containing polymer. Therefore, there is no possibility that the lubricant-containing polymer is subjected to an excessive stress at a position near the middle of each row, and the lubricant-containing polymer can sufficiently withstand the use conditions of high speed and high load. That is, the reliability with respect to the use conditions of high speed and high load can be improved.

  Further, in the space between the inner ring and the outer ring, at least the gap between the inner end face of each row of rollers and the guide ring, and the gap between the outer end face of each row of rollers and the inner ring fall-off collar are prevented. As a result, the lubrication state between the inner end surface of each row of rollers and the guide ring and between the outer end surface of each row of rollers and the collar for preventing the inner ring from falling off is good, and no lubricant-containing polymer is filled. The generated torque is reduced as compared with the case, and the temperature rise accompanying the rotation of the bearing is suppressed to a small range. Therefore, it is possible to prevent the possibility of the malfunction of the lubricant-containing polymer due to this excessive temperature rise, and it is possible to suppress the release rate of the lubricant from the lubricant-containing polymer small, It is possible to prevent the possibility of temperature rise.

  Further, when a lubricant-containing polymer is filled in the bearing according to the manufacturing method described in Japanese Patent Application Laid-Open No. 7-139551 by the present applicant, a roller and a lubricant are formed by a release agent film formed on the roller surface. A gap is formed between the containing polymer. As a result, the rotation of the rollers becomes smooth, and it is possible to further reduce the torque of the bearing and to suppress the temperature rise associated therewith.

  According to the present invention, since the cage is configured as an integral type, the movement of the rollers in each row is constrained by the cage, and the rollers in each row together with the cage for each row under high-speed and high-load use conditions. The lubricant does not move differently, and even when the lubricant-containing polymer is filled between the rows of rollers, no shear force acts on the lubricant-containing polymer. Therefore, there is no fear that the lubricant-containing polymer is subjected to unreasonable stress at a position near the middle of each row, and the lubricant-containing polymer can sufficiently withstand the use conditions of high speed and high load. That is, the reliability with respect to the use conditions of high speed and high load can be improved.

  Further, in the space between the inner ring and the outer ring, at least the gap between the inner end face of each row of rollers and the guide ring, and the gap between the outer end face of each row of rollers and the inner ring fall-off collar are prevented. As a result, the lubrication state between the inner end surface of each row of rollers and the guide ring and between the outer end surface of each row of rollers and the collar for preventing the inner ring from falling off is good, and no lubricant-containing polymer is filled. The generated torque is reduced as compared with the case, and the temperature rise accompanying the rotation of the bearing is suppressed to a small range. Therefore, it is possible to prevent the possibility of the malfunction of the lubricant-containing polymer due to this excessive temperature rise, and it is possible to suppress the release rate of the lubricant from the lubricant-containing polymer small, It is possible to prevent the possibility of temperature rise.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a cross-sectional view showing the configuration of the main part of a first embodiment of a self-aligning roller bearing according to the present invention, and FIG. 2 is a plan view of the self-aligning roller bearing of FIG.

  The self-aligning roller bearing has an inner ring 1 and an outer ring 2 as shown in FIG. The inner ring 1 is formed with two rows of raceways 1a, and a drop-off prevention collar 1b is provided at an outer end portion of each raceway 1a. The outer ring 2 is formed with tracks 2 a that face the tracks 1 a of the inner ring 1. Two rows of rollers 3 are arranged between the raceway 1a of the inner ring 1 and the raceway 2a of the outer ring 2, and the rollers 3 in each row are held by a cage 6 that is configured as an integral type. That is, the rollers 3 in each row are held by one cage 6. The material of the cage 6 is made of high strength brass, plastic with a reinforcing material such as glass fiber (for example, nylon 66) or the like, and considering the reliability such as strength, the material is preferably made of high strength brass. The cage 6 may be configured by integrating an iron separable cage after assembly of the bearing by electron beam welding. A guide wheel 7 is arranged between the cage 6 and the inner ring 1 so as to guide the rollers 3 in each row.

  A space existing between the inner ring 1 and the outer ring 2, a gap between each fall-off preventing collar 1b of the inner ring 1 and the outer end face of each row of rollers 3, and an inner end face of each row of rollers 3 and the guide ring 7 The gaps between them are each filled with a lubricant-containing polymer 8. As shown in FIG. 2, the filled lubricant-containing polymer 8 has three through holes 8 a extending from one end face toward the cage 6 and three through holes extending from the end face toward the guide wheel 7. A hole 8b is formed, and each of the through holes 8a and 8b is a hole formed by a filling jig used for filling a lubricant-containing polymer 8 described later. In the present embodiment, the lubricant-containing polymer 8 includes 20% by weight of high-density polyethylene (classified as a relatively low molecular weight), 5% by weight of ultra-high molecular weight polyethylene (classified as an ultra-high molecular weight), polyethylene A wax having a composition consisting of 5% by weight of wax (classified as wax) and 70% by weight of mineral oil is used, and its hardness is 83 HDA.

  Next, the lubricant-containing polymer is inserted into the space between the inner ring 1 and the outer ring 2, at least the gap between the fall-off prevention collars 1 b of the inner ring 1 and the outer end surface of the rollers 3 in each row, A method for filling the gap between the end face and the guide wheel 7 will be described.

  As a method for filling the lubricant-containing polymer, a method using a pair of filling jigs, and filling and firing the lubricant-containing polymer in a state where the bearing is supported so that the rotation axis is parallel to a horizontal support surface. In this embodiment, the former method is adopted. The latter method will be described in detail in a second embodiment described later.

  Here, the former method will be described with reference to FIG. FIG. 3 is a view for explaining a method of filling the lubricant-containing polymer in the self-aligning roller bearing of FIG.

  In the former method, as shown in FIG. 3, the set of filling jigs 9 and 10 described above is used. Each of the filling jigs 9 and 10 is made of a template whose one surface, that is, the inner surface faces the bearing. On the inner surface of the template plate, annular recesses 9a and 10a and rollers 3 are provided so as to receive the end surface of the outer ring 2. The annular convex portions 9b and 10b that face the outer end surface of the inner ring 1 and the annular concave portions 9c and 10c that receive the end surface of the inner ring 1 are formed. The protrusion 9b of the filling jig 9 is provided with a plurality of rod-like protrusions 11 and 12 that protrude perpendicularly from the inner surface. Each protrusion 11 abuts against a corresponding portion of the retainer 6 and has a length that slightly moves the retainer 6 from the roller 3 in one row toward the roller 3 in the other row. They are arranged at equiangular intervals along the circumferential direction of the portion 9b. Each protrusion 12 abuts against a corresponding portion of the guide wheel 7 and has a length that slightly moves the guide wheel 7 from the roller 3 in one row toward the roller 3 in the other row. They are arranged at equiangular intervals along the circumferential direction of the portion 9b. When each projection 12 abuts on a corresponding portion of the guide wheel 7 and moves the guide wheel 7, a gap is generated between the inner end surface of the roller 3 in one row and the guide wheel 7, and at the same time, each projection 11. Each of the protrusions 11 and 12 so that a gap is formed between the inner end surface of the roller 3 in the other row and the guide wheel 7 by moving the retainer 6 while abutting against the corresponding retainer 6 portion. The length of is determined.

  In the present embodiment, the number of the protrusions 11 is 3, and the protrusions 11 are arranged at an angular interval of 120 degrees. Similarly, the number of the protrusions 12 is 3, and the protrusions 12 are arranged at an angular interval of 120 degrees.

  One filling jig 9 and the other filling jig 10 are fitted to the respective end faces of the bearing with reference to the inner diameter of the inner ring. The fastening bracket 13 is a jig for fixing and holding the protrusions 11 and 12.

  When the lubricant-containing polymer is filled using the pair of filling jigs 9 and 10, first, the filling jig 9 receives the end face of the outer ring 2 in the recess 9a and the end face of the inner ring 1 in the recess 9c. It fits into one end face of the bearing. When the filling jig 9 is fitted, the convex portion 9b is opposed to the outer end surface of the roller 3 in one row while forming a gap, and the projection 12 is in contact with the corresponding portion of the guide wheel 7 As a result, the guide wheel 7 is moved to form a gap between the inner end face of the roller 3 in one row and the guide wheel 7, and at the same time, the retainer 6 is brought into contact with each projection 11 and the corresponding portion of the retainer 6. Is moved to form a gap between the inner end face of the other row of rollers 3 and the guide wheel 7. When the filling jig 9 is fitted, the gap between each drop-off preventing collar 1b of the inner ring 1 and the outer end surface of the roller 3 in each row is maintained.

  The filling jig 9 fitted into one end face of the bearing is placed on a horizontal support surface 14. Next, an unsintered raw material of the lubricant-containing polymer 8 is placed in a space between the inner ring 1 and the outer ring 2, and the unsintered raw material of the lubricant-containing polymer 8 is disposed between the inner end face of the roller 3 in one row and the guide wheel. 7, a gap between the inner end face of the other row of rollers 3 and the guide ring 7, and a gap between each fall-off preventing collar 1 b of the inner ring 1 and the outer end face of each row of rollers 3. After filling the space between the inner ring 1 and the outer ring 2 and fitting the filling jig 10 into the other end face of the bearing, the unfired raw material of the lubricant-containing polymer 8 is heated and cooled to thereby lubricate the lubricant. The contained polymer 8 is filled. In this case, a slight gap is formed between the convex portions 9b and 10b and the outer end surface of the three. That is, the lubricant-containing polymer 8 includes a gap between the inner end face of each row of rollers 3 and the guide ring 7 and a gap between each fall prevention collar 1b of the inner ring 1 and the outer end face of each row of rollers 3. The space between the inner ring 1 and the outer ring 2 is filled.

  The filling jigs 9 and 10 are removed after filling the lubricant-containing polymer 8, but when the filling jig 9 is removed, the projections 11 and 12 are pulled out from the lubricant-containing polymer 8, so that the filling jig 9 is fitted. As described above, three through holes 8a extending from the end surface toward the cage 6 and three through holes 8b extending from the end surface toward the guide wheel 7 are formed on the end surface of the bearing. (See FIG. 2). Further, the surplus of the lubricant-containing polymer formed on the outer end surface of the roller 3 is appropriately removed as necessary.

  Thus, in this embodiment, since the cage 6 is configured as an integral type, the movement of the rollers 3 in each row is constrained by the cage 6, and the rollers 3 in each row are operated under a high-speed and high-load use condition. There is no different movement for each row together with the cage 6, and no shear force acts on the lubricant-containing polymer 8 filled between the rows of the rollers 3. Therefore, there is no fear that the lubricant-containing polymer 8 is subjected to unreasonable stress at a position near the middle of each row, and the reliability with respect to use conditions of high speed and high load can be sufficiently enhanced.

  Further, in the space between the inner ring 1 and the outer ring 2, at least the gap between the inner end face of each row of rollers 3 and the guide ring 7, and between the outer end face of each row of rollers 3 and the collar 1b for preventing the inner ring 1 from falling off. Since the lubricant-containing polymer 8 is filled in the gaps, the lubrication between the inner end surface of each row of rollers 3 and the guide wheel 7 and between the outer end surface of each row of rollers 3 and the fall-off collar 1b of the inner ring 1 is performed. The condition is good and the generated torque is lower than when the lubricant-containing polymer 8 is not filled, and the temperature rise accompanying the rotation of the bearing is suppressed to a small range. Therefore, the possibility of the malfunction of the lubricant-containing polymer 8 due to this excessive temperature rise can be prevented in advance, and the release rate of the lubricant from the lubricant-containing polymer 8 can be suppressed small, It is possible to prevent the possibility of excessive temperature rise.

  In the present embodiment, the reliability for the filling operation can be improved by using guide wheels instead of the guide collars.

(Second embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 4 is a view for explaining a method of filling a lubricant-containing polymer used in the second embodiment of the self-aligning roller bearing according to the present invention.

  In the present embodiment, the lubricant-containing polymer is filled in a state in which the bearing is supported so that the rotation axis is parallel to the horizontal support surface as a method of filling the lubricant-containing polymer with respect to the first embodiment described above. The difference is that a method of solidifying by firing is used and a lubricant-containing polymer having a different composition is used.

  In this filling method, since the inner end surface of the roller 3 is not pressed against the guide wheel 7 by supporting the bearing so that the rotation axis is parallel to the horizontal support surface, the inner end surface of the roller 3 and the guide wheel 7 are not pressed. A gap between the two is maintained, and the gap is filled with the lubricant-containing polymer.

  As a specific method for carrying out this method, as shown in FIG. 4, a bearing is held in the internal space of a set of molds 20 so that the rotation axis is parallel, and an external injection molding machine is used. Injecting and filling the plasticized lubricant-containing polymer into the space between the inner ring 1 and the outer ring 2 through a plurality of pin gates provided in the portion 20a facing the roller 3 of the bearing of each mold 20, There is an injection molding method in which the lubricant-containing polymer is cooled and solidified in the mold 20. As an injection molding machine used in this method, there is one described in Japanese Patent Application Laid-Open No. 8-309793 by the present applicant.

  The lubricant-containing polymer filled by this injection molding method is 20% by weight of polymethylpentene (classified as a relatively low molecular weight) and 7% by weight of high-density polyethylene (classified as a relatively low molecular weight). And a composition comprising 3% by weight of ultrahigh molecular weight polyethylene (classified as ultrahigh molecular weight) and 70% by weight of dialkyldiphenyl ether, and its hardness is 80 HDA.

(Third embodiment)
Next, a third embodiment of the present invention will be described.

  This embodiment is different from the above-described first embodiment in that a lubricant-containing polymer having a different composition is used. The method for filling the lubricant-containing polymer is the same as in the first embodiment. Specifically, the lubricant-containing polymer is 20% by weight of high-density polyethylene (classified as a relatively low molecular weight), 10% by weight of ultra-high molecular weight polyethylene (classified as ultra-high molecular weight), and 70% of mineral oil. % Having a composition consisting of% is used, and its hardness is 92 HDA.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described.

  This embodiment is different from the above-described first embodiment in that a lubricant-containing polymer having a different composition is used. The method for filling the lubricant-containing polymer is the same as in the first embodiment. Specifically, as the lubricant-containing polymer, 20% by weight of high density polyethylene (classified as a relatively low molecular weight), 8% by weight of ultra high molecular weight polyethylene (classified as ultra high molecular weight), polyethylene wax ( A material having a composition of 2% by weight (classified as wax) and 70% by weight of mineral oil is used, and its hardness is 88 HDA.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described.

  This embodiment is different from the above-described first embodiment in that a lubricant-containing polymer having a different composition is used. The method for filling the lubricant-containing polymer is the same as in the first embodiment. Specifically, the lubricant-containing polymer is 10% by weight of high density polyethylene (classified as a relatively low molecular weight), 2% by weight of ultra high molecular weight polyethylene (classified as ultra high molecular weight), polyethylene wax ( A material having a composition of 8% by weight (classified as wax) and 80% by weight of mineral oil is used, and its hardness is 63 HDA.

  Next, a bearing rotation test is performed for each of the above-described embodiments (from the first to third embodiments) and Comparative Example 1, and the measurement results of the temperature near the inner ring and the bearing torque are described with reference to FIGS. 5 and 6. explain. FIG. 5 is a diagram showing a measurement result of the temperature near the inner ring with respect to the rotational speed in each embodiment (from the first embodiment to the third embodiment), and FIG. 6 is a diagram showing each embodiment (from the first embodiment to the third embodiment). FIG. 6 is a diagram illustrating a measurement result of bearing torque with respect to the rotational speed in Comparative Example 1.

  Here, the bearing rotation test is carried out using a self-aligning roller bearing (model number -22311) having an inner diameter of 55 mm, an outer diameter of 120 mm, and a width of 43 mm, and Fr = 2000 kgf and Fa = 250 kgf are set as load conditions. . Comparative Example 1 has a configuration based on the prior art, and uses a lubricant-containing polymer having the same composition as that of the first embodiment, and uses a separate type holder instead of the integrated type holder.

  As apparent from FIGS. 5 and 6, each of the above-described embodiments shows that the temperature near the inner ring and the bearing torque are at a low level as compared with Comparative Example 1 in the rotational speed range of 250 to 1000 rpm. . This is considered to be due to the difference in whether or not the lubricant-containing polymer is filled in the gap between the inner end face of the roller and the guide ring. Further, in Comparative Example 1, when the rotation was continued while maintaining the rotation speed of 1000 rpm, the temperature near the inner ring further increased, and a rapid increase in bearing torque was observed. When the rotation of the bearing was stopped at that time and the bearing was observed, it was confirmed that the lubricant-containing polymer was cut near the middle of the roller row and completely separated from the bearing. This phenomenon is a phenomenon that is not seen in each embodiment in which the cage is configured integrally.

  In the third embodiment in which the hardness [HDA] of the lubricant-containing polymer exceeds 90, the temperature near the inner ring and the bearing torque are slightly smaller than those in the first and second embodiments in the range of 65 to 90. It can be seen that it is expensive. From this, it can be seen that the hardness of the lubricant-containing polymer affects the temperature near the inner ring and the bearing torque, and consequently the bearing life is also expected to be affected.

  Further, when comparing the first embodiment and the second embodiment, at the rotation speed of 1000 rpm where the temperature near the inner ring is increased to a considerably high temperature, the first embodiment is accompanied by a temperature increase. Although a tendency to increase the bearing torque due to softening of the lubricant-containing polymer is observed, this tendency is not particularly observed in the second embodiment. This is because the melting point of polymethylpentene, which accounts for 2/3 of the resin constituting the lubricant-containing polymer of the second embodiment, is as high as 503 to 513 K (230 to 240 ° C.), so it contains polyethylene Even so, it is expected that the softening phenomenon is suppressed at a temperature of about 343 to 353 K (70 to 80 ° C.). From this, it is considered that the use up to the number of revolutions (dmn) where the temperature rise is expected can be achieved by filling the lubricant-containing polymer based on polymethylpentene.

  Next, an endurance test is performed on each of the embodiments from the first embodiment to the fifth embodiment and Comparative Examples 1 to 3, and the respective durability will be described.

  Here, the durability test was performed using the spherical roller bearing (22311). In this durability test, Fr = 2000 kgf and Fa = 250 kgf as load conditions and 200,300,400,500, 600, 700, 800, 900, 1000, 1100, 1200, 1300 rpm each rotation speed is set, the bearing is continuously rotated at each rotation speed for 200 hours, and the rotation speed rotated without abnormality is measured as the maximum rotation speed. .

  In Comparative Example 2, a lubricant-containing polymer having the same composition as that of the third embodiment is used, and a separation type cage is used instead of the integral type cage. In Comparative Example 3, a lubricant-containing polymer having the same composition as that of the second embodiment is used, and a separation type cage is used instead of the integral type cage.

  In each embodiment and Comparative Examples 1 to 3, as shown in Table 1, the maximum rotational speed of the second embodiment is the highest, 1200 rpm. As described above, this means that the melting point of polymethylpentene occupying 2/3 of the resin constituting the lubricant-containing polymer of the second embodiment is 503 to 513 (230 to 240 ° C.). Since it is high, even if it contains polyethylene, it is considered that the softening phenomenon is suppressed at a temperature of about 343 to 353 (70 to 80 ° C.), and the second embodiment is suitable for use under higher speed and higher load conditions. It shows that it can endure.

  In addition, the maximum rotational speeds of the first, third, fourth, and fifth embodiments filled with the lubricant-containing polymer having the same composition are the same as those of these embodiments. Alternatively, the maximum rotational speeds of Comparative Example 1 and Comparative Example 2 filled with the lubricant-containing polymer having substantially the same composition indicate a low rotational speed. This means that the cage can be constructed as a single unit and can withstand use under high-speed and high-load conditions by filling the gap between the inner end face of the roller and the guide wheel with a lubricant-containing polymer. It shows that a bearing with sufficiently high reliability for high load operating conditions can be obtained.

It is sectional drawing which shows the principal part structure of 1st Embodiment of the self-aligning roller bearing which concerns on this invention. It is a top view of the self-aligning roller bearing of FIG. It is a figure for demonstrating the filling method of the lubricant containing polymer in the self-aligning roller bearing of FIG. It is a figure for demonstrating the filling method of the lubricant containing polymer used for the 2nd Embodiment of the self-aligning roller bearing which concerns on this invention. It is a figure showing the measurement result of the inner ring vicinity temperature with respect to the rotation speed in each embodiment (from 1st form to 3rd form) and comparative example 1. It is a figure showing the measurement result of the bearing torque with respect to the rotation speed in each embodiment (from 1st form to 3rd form) and the comparative example 1. It is sectional drawing which shows the principal part structure of the conventional self-aligning roller bearing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring 1a, 2a Track 1b Fall-off prevention collar 2 Outer ring 3 Inner ring 6 Cage 7 Guide wheel 8 Lubricant containing polymer 9, 10 Filling jig 11, 12 Protrusion 20 Mold

Claims (1)

An inner ring having two rows of raceways, each of which has a collar that prevents the outer race from falling off, an outer race on which a raceway facing each raceway of the inner race, a raceway of the inner race, and a raceway of the outer race, Two rows of rollers arranged between the rollers, a cage that holds the rollers of each row, and a guide that is arranged to guide the rollers of each row between the cage and the inner ring The retainer is integrally formed, and a space between the inner end surface of each row of rollers and the guide ring in the space between the inner ring and the outer ring, and the outer side of each row of rollers. A method of manufacturing a self-aligning roller bearing in which a gap between an end face and a collar for preventing the inner ring from falling is filled with a lubricant-containing polymer,
A filling jig in which a concave portion for receiving an end surface of the inner ring and an annular convex portion provided with a plurality of rod-shaped protrusions that protrude perpendicularly from the inner surface are opposed to the outer end surfaces of the respective rows of rollers. Fit into the self-aligning roller bearing,
Causing a gap the recess receiving an end face of the inner ring, filling the lubricant-containing polymer in the gap between the front Symbol drop-off preventing flange of the inner ring and the outer end face of the roller in each row,
The plurality of protrusions abut against the cage and the guide wheel to move the cage and the guide wheel, so that the lubricant is provided between the inner end surface of the roller in each row and the guide wheel. Creating a gap filling the containing polymer;
The lubricant-containing polymer is a composition ratio in which the polyolefin resin is 10 to 50% by weight and the lubricant is 90 to 50% by weight with respect to the total weight. 8 to 48% by weight of low molecular weight, 2 to 10% by weight of ultra high molecular weight, composition ratio of polyolefin resin in which the total of these three resins is 10 to 50% by weight, and a range of 80 to 90 A lubricant-containing polymer having a hardness [HDA] (durometer A scale hardness) of the polymer in the above-mentioned range is obtained by using the generated gap between the inner end surface of each row of rollers and the guide wheel and the rollers in each row. A method of manufacturing a self-aligning roller bearing, comprising filling a gap between an outer end surface of the inner ring and a collar for preventing the inner ring from falling off.

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