JP6039431B2 - Wheel bearing device - Google Patents

Description

  The present invention relates to a wheel bearing device for rotatably supporting a wheel of an automobile or the like with respect to a suspension device, and more particularly to a full floating type wheel bearing device for supporting a driving wheel with a wheel bearing.

  Many automobiles having a frame-structured body such as a truck adopt a conventional full floating type as an axle structure of a drive wheel. Also, recent drive wheel support structures are often adopted as a structure in which double row rolling bearings are unitized for the purpose of improving assemblability and reducing weight and size. As an example of the conventional structure, a wheel bearing device as shown in FIG. 11 is known.

  In this wheel bearing device, a drive shaft 52 connected to a differential (not shown) is inserted into an axle tube 51, and a double row tapered roller bearing 53 is mounted on the outer diameter surface of the axle tube 51. . A hub wheel 54 rotatably supported by the double row tapered roller bearing 53 is connected to a flange 56 of the drive shaft 52 via a hub bolt 55. A pair of inner rings 57, 58 of the double row tapered roller bearing 53 are coupled by a connecting ring 59, are fitted on the shaft portion of the axle tube 51, and are fastened and fixed by a fixing nut 60. The outer ring 61 of the double row tapered roller bearing 53 is fitted in the hub ring 54 and is fixed in the axial direction in a state where both ends are sandwiched between the flange 56 and the brake rotor 62. In the annular space between the inner rings 57, 58 and the outer ring 61, double-row tapered rollers 63 are rotatably accommodated by a cage 64, and seals 65 are attached to both ends to seal the bearing interior. Yes.

  An annular step 66 is formed at the inner end of the differential inner ring 58 of the pair of inner rings 57, 58, and a seal ring 67 made of an elastic member is mounted. In addition, an annular convex portion 68 is formed on the outer peripheral surface of the butted portion of the pair of inner rings 57 and 58, and a connecting ring 59 is attached to the annular convex portion 68, and the pair of inner rings 57 and 58 are integrally coupled. .

  As shown in an enlarged view of FIG. 12 (a), the connecting ring 59 includes a cored bar 69 including a cylindrical part 69a and flanges 69b and 69b extending radially inward from both ends of the cylindrical part 69a. A substantially cylindrical seal member 70 is integrally joined to the inner periphery of the cylindrical portion 69a of the core metal 69 by vulcanization adhesion. The cored bar 69 is formed by press working from a steel plate having a rust-preventing ability, has a substantially U-shaped cross section, and the surface is subjected to hardening treatment in the range of 40 to 55 HRC by tempering or quenching. . On the other hand, the seal member 70 is made of synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and has a protruding portion 70a formed at the center in the axial direction.

  Note that, on the outer periphery of the front end portion of the inner rings 57 and 58 to which the connecting ring 59 is attached, an annular groove 71 and an end surface 57a of the groove 71 are shown as enlarged in FIG. An annular convex portion 68 is formed on the side. The wall surface 68a on the concave groove 71 side of the annular convex portion 68 is formed in a substantially vertical surface, and the wall surface 68b on the end surface 57a side is formed in a tapered surface having an inclination angle α of 10 to 30 °.

  Here, the inner diameter d1 of the flange portion 69b of the cored bar 69 is set to be larger than the outer diameter D1 of the concave groove 71 of the inner rings 57 and 58 and smaller than the outer diameter D2 of the annular convex portion 68 (D1 < d1 <D2), and the inner diameter d2 of the protruding portion 70a of the seal member 70 is set smaller than the outer diameter D3 of the end portions of the inner rings 57, 58 (d2 <D3). Then, the cored bar 69 is fitted and inserted along the wall surface 68 b of the annular convex portion 68, and the flange portion 69 b is locked to the concave groove 71, whereby the pair of inner rings 57 and 58 are integrally coupled by the connecting ring 59. .

  The double ring tapered roller bearing 53 can be easily assembled while correcting the misalignment of the pair of inner rings 57 and 58 by the connecting ring 59, and the protruding portion 70 a of the seal member 70 is the end of the inner rings 57 and 58. It is in close contact with the outer periphery in an elastically deformed state, and it is possible to prevent the differential oil from entering the bearing from the abutting surfaces of the pair of inner rings 57 and 58, and to prevent the grease inside the bearing from leaking to the outside. . Therefore, the sealing performance of the double-row tapered roller bearing 53 can be secured, and the cost can be reduced by reducing the number of parts and the processing steps (see, for example, Patent Document 1).

JP 2011-148409 A

  In such a conventional wheel bearing device, the grease filled in the bearing does not circulate evenly during operation, but may remain in the center of the double row tapered roller bearing 53 and not contribute to lubrication. is there. This is more pronounced with wider bearings. For this reason, conventionally, a large amount of grease had to be enclosed in advance in order to obtain good lubrication. This not only increases the torque due to the stirring resistance of the grease, but also has a problem that the durability is hindered by the temperature rise of the bearing.

  The present invention has been made in view of such a conventional problem, and provides a wheel bearing device that ensures sealing performance and effectively circulates grease inside the bearing to improve durability. For the purpose.

In order to achieve such an object, the invention according to claim 1 of the present invention includes an outer ring in which a double row outer rolling surface is integrally formed on an inner periphery, and an outer rolling surface of the double row on the outer periphery. A pair of inner rings formed with opposing inner rolling surfaces, a double-row rolling element housed in a freely rolling manner between the rolling surfaces of the inner ring and the outer ring, and formed between the outer ring and the inner ring A seal mounted on both side openings of the annular space, an annular convex portion is formed on the front side end of the inner ring, a connecting ring is mounted on the annular convex portion, and the inner ring is integrally coupled, the connecting ring is formed in shape of a steel plate or al cross-section substantially U, a cylindrical portion, a core metal having a flange portion extending at both ends radially inward from the cylindrical portion, the cylindrical portion of the metal core is joined to the inner periphery at one-body, in a wheel bearing apparatus provided with a sealing member made of synthetic rubber to be elastically contacted with an end portion of said inner ring, The outer periphery of the connexin gold annular guide member is integrally joined, together with the guide member is provided with an inclined surface gradually projecting radially outward, the inner diameter between the outer raceway surfaces of the double row of outer race The guide members made of synthetic rubber are integrally joined to each other, and the guide members are provided with inclined surfaces that gradually protrude inward in the radial direction from both ends toward the axial central portion.

Thus, it is a sealed type wheel bearing device composed of double row rolling bearings, an annular convex portion is formed at the front side end of the inner ring, and a connecting ring is attached to the annular convex portion so that the inner ring is integrated. coupled to the coupling ring is formed in shape of a steel plate or al cross-section substantially U, a cylindrical portion, a core metal having a flange portion extending at both ends radially inward from the cylindrical portion, the metal core is the bonding to the inner peripheral one body of the cylindrical part, joined at the wheel bearing apparatus provided with a synthetic rubber seal member is elastically contacted with the inner ring of the end portion, an annular guide member integrally with the outer periphery of the core The guide member has an inclined surface that gradually protrudes radially outward, and a synthetic rubber guide member is integrally joined to the inner diameter between the outer rolling surfaces of the double rows of the outer ring. since member is provided with an inclined surface gradually projecting radially inwardly toward the axial center portion from both ends The grease inside the bearing can be prevented from leaking to the outside from the abutting surfaces of the pair of inner rings, and the grease filled in the bearing is prevented from being unevenly distributed in the center of the bearing, so that the grease can be effectively applied to the inside of the bearing. Thus, it is possible to provide a wheel bearing device that is circulated in a continuous manner to improve durability.

  Preferably, as in the invention described in claim 2, an axle tube through which a drive shaft connected to the differential is inserted, and a wheel mounting flange for mounting a wheel on the outer periphery are integrally provided, and the drive is performed via a hub bolt. A hub wheel coupled to a shaft flange, and the outer ring is press-fitted into the hub wheel and fixed in the axial direction while being sandwiched between the flange of the drive shaft and a brake rotor, and the shaft of the axle tube If the pair of inner rings are press-fitted into the part, in the full floating type wheel bearing device, the wheel bearing can be easily assembled while correcting the misalignment of the pair of inner rings, and the pair of inner rings It is possible to prevent the differential oil from entering the inside of the bearing from the abutting surface and to prevent the grease inside the bearing from leaking to the outside. It is possible to ensure the sex.

According to a third aspect of the present invention, an annular concave groove is formed in the vicinity of the annular convex portion, the wall surface of the annular convex portion on the concave groove side is a substantially vertical surface, and the end surface side of the inner ring If the wall surfaces are respectively formed on tapered surfaces having a predetermined inclination angle, the connecting ring can be easily attached to the end portion of the inner ring, and the assembly workability can be improved.

Further, as in the invention described in claim 4 , a plurality of recesses are formed in the collar portion of the core metal at equal intervals in the circumferential direction, and these recesses are staggered at both ends of the cylindrical portion of the core metal. If it is formed in a shape, the connecting ring is easily elastically deformed during insertion, and while maintaining the strength of the connecting ring, its insertability can be further improved and assembly workability can be improved.

Moreover, if the said core metal is formed in the end ring shape which has a slit in one place of the circumferential direction like invention of Claim 5 , a connecting ring will be easily expanded and inserted at the time of insertion. As a result, the assembly workability can be further improved.

Further, as in the invention described in claim 6 , the guide member may be formed in a substantially triangular cross section.

In addition, if a coating layer made of a fluororesin is formed on the surface of the guide member as in the invention described in claim 7 , the oil repellency is improved and the fluidity is improved by suppressing the staying and adhesion of grease. be able to.

In the wheel bearing device according to the present invention, an outer ring in which a double row outer rolling surface is integrally formed on the inner periphery, and an inner rolling surface that faces the outer rolling surface of the double row is formed on the outer periphery. A pair of inner rings, a double-row rolling element housed in a freely rolling manner between the rolling surfaces of the inner ring and the outer ring, and both side openings of an annular space formed between the outer ring and the inner ring comprising a has been sealed, annular convex portion is formed on the front end of the inner ring, the inner ring the annular protrusion coupling ring is attached to are bound together ,, said connecting ring, the steel sheet or et sectional is formed in a shape of a plane substantially U, a cylindrical portion, a core metal having a flange portion extending at both ends radially inward from the cylindrical portion, the inner periphery of the cylindrical portion of the metal core is bonded to one body In the wheel bearing device including a synthetic rubber seal member elastically contacted with an end portion of the inner ring, an annular guide is provided on the outer periphery of the core metal. Material is joined integrally with and includes an inclined surface, the inner diameter synthetic rubber guide member between the outer raceway surfaces of the double row of the outer ring is integrally the guide member is gradually projecting radially outward Since the guide member has an inclined surface that gradually protrudes radially inward from both ends toward the axial center , grease inside the bearing leaks to the outside from the abutting surfaces of the pair of inner rings. A wheel bearing device that prevents the grease filled in the bearing from being unevenly distributed in the center of the bearing and effectively circulates the grease inside the bearing to improve durability. Can be provided.

It is a longitudinal cross-sectional view which shows the wheel bearing apparatus with which the wheel bearing which concerns on this invention was mounted | worn. It is a longitudinal cross-sectional view which shows the wheel bearing of FIG. FIG. 3 is an enlarged view of a main part of FIG. 2. It is a front view which shows the connection ring of FIG. (A) is the front view which shows the other modification of the connection ring of FIG. 3, (b) is the V arrow directional view of (a), (c) is the principal part enlarged view of (a). It is a front view which shows the modification of the connection ring of FIG. (A)-(d) is a principal part enlarged view which shows the modification of the guide member of FIG. (A)-(c) is a principal part enlarged view which shows the modification of the guide member of FIG. It is a longitudinal cross-sectional view which shows 2nd Embodiment of the wheel bearing which concerns on this invention. (A), (b) is a principal part enlarged view which shows the modification of the guide member of FIG. It is a longitudinal cross-sectional view which shows the conventional wheel bearing apparatus. (A) is a longitudinal cross-sectional view which shows the connection ring of FIG. 11, (b) is a principal part enlarged view of the inner ring | wheel of FIG.

  An axle tube through which a drive shaft connected to the differential is inserted, a wheel mounting flange for mounting a wheel on the outer periphery, and a hub wheel connected to the flange of the drive shaft via a hub bolt, and the hub wheel And a wheel bearing device mounted between a shaft portion of the axle tube and a wheel bearing for rotatably supporting the wheel, wherein the wheel bearing is press-fitted into an inner diameter of the hub wheel. An outer ring in which a double row outer rolling surface is integrally formed on the inner periphery, a pair of inner rings in which an inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and these inner rings A double row rolling element accommodated between both rolling surfaces of the outer ring, and a seal mounted on both side openings of an annular space formed between the outer ring and the inner ring; An annular convex part is formed at the front side end of the annular convex part. The inner ring is integrally connected and the connecting ring is formed into a substantially U-shaped cross section by pressing from a steel plate, and a cylindrical portion and a flange portion extending radially inward from both ends of the cylindrical portion And a bearing device for a wheel provided with a sealing member made of synthetic rubber that is integrally joined to the inner periphery of the cylindrical portion of the core metal by vulcanization and elastically contacts the end portion of the inner ring. An annular guide member made of synthetic rubber that is integrally joined to the outer periphery of the cylindrical portion of the core metal by vulcanization adhesion and has an inclined surface that gradually protrudes radially outward. Synthetic rubber guide members are integrally joined to the inner diameter between the outer rolling surfaces of the rows by vulcanization, and the inclined surfaces gradually protrude radially inward from both ends toward the central portion in the axial direction. Is formed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a longitudinal sectional view showing a wheel bearing device equipped with a wheel bearing according to the present invention, FIG. 2 is a longitudinal sectional view showing the wheel bearing, and FIG. 3 is an enlarged view of a main part of FIG. 4 is a front view showing the connecting ring of FIG. 3, FIG. 5A is a front view showing another modified example of the connecting ring of FIG. 3, and FIG. 4B is a view taken in the direction of arrow V in FIG. (C) is an enlarged view of the main part of (a), FIG. 6 is a front view showing a modification of the connecting ring of FIG. 4, and FIGS. 7 (a) to (d) are modifications of the guide member of FIG. The principal part enlarged view which shows an example, FIG. 8 (a)-(c) is a principal part enlarged view which shows the modification of the guide member of FIG. In the following description, the side closer to the outer side of the vehicle when assembled to the vehicle is referred to as the outer side (left side in FIG. 1), and the side closer to the center is referred to as the inner side (right side in FIG. 1).

  In this wheel bearing device, a drive shaft 2 connected to a differential (not shown) is inserted into an axle tube 1, and a wheel bearing 3 comprising a double row tapered roller bearing on the outer diameter surface of the axle tube 1. Is installed. A hub wheel 4 rotatably supported by the wheel bearing 3 is connected to a flange 6 of the drive shaft 2 via a hub bolt 5. A pair of inner rings 7 and 8 of the wheel bearing 3 are coupled by a connecting ring 9 described later, and are fitted onto the shaft portion of the axle tube 1 and are fastened and fixed by a fixing nut 10. An annular recess 13 is formed in the inner periphery of the inner ring 8 on the inner side of the pair of inner rings 7 and 8, and a seal ring 14 made of an elastic member is attached. Further, the outer ring 11 of the wheel bearing 3 is fitted in the hub ring 4 and fixed in the axial direction in a state where both ends thereof are sandwiched between the respective end surfaces of the flange 6 and the brake rotor 12 integrally formed with the drive shaft 2. Has been.

  As shown in an enlarged view in FIG. 2, the wheel bearing 3 includes an outer ring 11 formed with tapered double-row outer rolling surfaces 11 a, 11 a that are opened outward on the inner periphery, and an inner ring formed on the outer ring 11. A pair of inner rings 7, 8 having tapered inner rolling surfaces 7a, 7a formed on the outer periphery and facing the double-row outer rolling surfaces 11a, 11a on the outer periphery and accommodated between both rolling surfaces. Double-row rolling elements (conical rollers) 15 and 15 and cages 16 and 16 that hold the double-row rolling elements 15 and 15 so as to roll freely.

  A large flange 7b for guiding the rolling element 15 is formed on the large diameter side (rear side) of the inner rolling surface 7a of the pair of inner rings 7, 8, and the smaller diameter side (front side) of the inner rolling surface 7a. ) Is provided with a gavel 7c for preventing the rolling element 15 from falling off. The pair of inner rings 7 and 8 are set in a state where the end surfaces 7d on the small diameter side (front side) are abutted with each other, and constitute a so-called back-to-back type double row tapered roller bearing. Seals 18, 18 are attached to the opening of the annular space formed between the outer ring 11 and the pair of inner rings 7, 8, leakage of the lubricating grease enclosed in the bearing to the outside, rainwater and Dust and the like are prevented from entering the bearing.

  The outer ring 11, the inner rings 7, 8 and the rolling element 15 are made of high carbon chrome bearing steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching. In addition, although the wheel bearing 3 which consists of the double row tapered roller bearing which used the rolling element 15 as the tapered roller was illustrated here, it is comprised not only in this but the double row angular ball bearing which uses the ball for the rolling element. Also good.

  Here, in this embodiment, the annular convex part 17 is formed in the outer periphery of the edge part of the front side of a pair of inner ring | wheels 7 and 8. FIG. A connecting ring 9 is attached to the annular protrusion 17, and a pair of inner rings 7, 8 are coupled together in the axial direction. The connecting ring 9 includes a metal core 19, and a seal member 20 and a guide member 21 that are integrally joined to the metal core 19 by vulcanization adhesion.

  The core metal 19 is a steel plate having rust prevention capability, such as an austenitic stainless steel plate (JIS standard SUS304), a ferritic stainless steel plate (JIS standard SUS430), or a steel plate such as tool steel or spring steel. Is formed by pressing and has a substantially U-shaped cross section. As shown in an enlarged view in FIG. 3, a cylindrical portion 19a and a flange portion extending radially inward from both ends of the cylindrical portion 19a. 19b, 19b. The core bar 19 is subjected to curing treatment in the range of 40 to 55 HRC by tempering or quenching on the surface. Thereby, desired intensity | strength (shearing force) is securable.

  On the other hand, the seal member 20 is integrally joined to the inner periphery of the cylindrical portion 19a of the core metal 19 by vulcanization and is formed in a substantially cylindrical shape. The seal member 20 is made of a synthetic rubber such as NBR (acrylonitrile-butadiene rubber), and has a protruding portion 20a formed at the center in the axial direction. In addition to NBR, the material of the seal member 20 is excellent in heat resistance and chemical resistance, such as HNBR (hydrogenated acrylonitrile butadiene rubber), EPDM (ethylene propylene rubber), etc., which have excellent heat resistance. Examples thereof include ACM (polyacrylic rubber), FKM (fluororubber), and silicon rubber.

  An annular concave groove 22 is formed on the outer periphery of the front end of the inner rings 7 and 8 to which the connecting ring 9 is attached, and an annular convex portion 17 is formed on the end surface 7d side of the concave groove 22. A wall surface 17a on the concave groove 22 side of the annular protrusion 17 is formed in a substantially vertical surface, and a wall surface 17b on the end surface 7d side is formed in a tapered surface having an inclination angle α of 10 to 30 °. In addition, when the inclination angle α exceeds 30 °, the insertion property of the connecting ring 9 to be described later is remarkably deteriorated. In addition to being enlarged, the insertion property of the connecting ring 9 is lowered, and the assembling workability is deteriorated.

  Here, the inner diameter of the flange portion 19b of the core metal 19 is set to be larger than the outer diameter of the concave groove 22 of the inner rings 7 and 8 and smaller than the outer diameter of the annular convex portion 17, and the seal member The inner diameter of the 20 projecting portions 20 a is set to be smaller than the outer diameter of the end portions of the inner rings 7, 8. Then, the cored bar 19 is fitted and inserted along the wall surface 17 b of the annular convex part 17, and the flange part 19 b is locked in the concave groove 22, whereby the pair of inner rings 7 and 8 are integrally coupled by the connecting ring 9. .

  While correcting the misalignment of the pair of inner rings 7, 8 with the connecting ring 9, the wheel bearing 3 can be easily assembled, and the protruding portion 20 a of the seal member 20 is elastic on the outer periphery of the end portions of the inner rings 7, 8. It adheres in a deformed state, and it is possible to prevent the differential oil from entering the bearing from the butted surfaces of the pair of inner rings 7 and 8, and to prevent the grease inside the bearing from leaking to the outside. Therefore, the sealing performance of the wheel bearing 3 can be ensured, and the cost can be reduced by reducing the number of parts and processing steps.

  Here, the guide member 21 is integrally joined to the outer periphery of the cylindrical portion 19a of the core metal 19 by vulcanization adhesion. The guide member 21 is made of synthetic rubber such as NBR, and gradually protrudes radially outward from both ends toward the axial central portion, and its inclined surface is formed into an arcuate concave surface. As a result, it is possible to provide a wheel bearing device in which the grease filled in the bearing is prevented from being unevenly distributed in the center of the bearing and the grease is effectively circulated inside the bearing to improve durability. Furthermore, by applying a fluororesin coating to the surface of the guide member 21, the oil repellency is improved, and the fluidity can be enhanced by suppressing the retention and adhesion of grease.

  In the case of inner ring rotation, the grease staying in this part due to the centrifugal force accompanying the rotation of the bearing is injected toward the opposite road surface side (upward in the figure) as indicated by the arrow in the figure, and the outer rolling surface 11a. , 11a, the grease can easily flow. Further, in the case of rotating the outer ring, the grease staying in the guide member 21 can flow along the slope and flow to the road surface side (downward in the figure), and the grease can easily flow to the outer rolling surface 11a.

  In addition to NBR, examples of the material of the guide member 21 include HNBR, EPDM, etc. excellent in heat resistance, ACM, FKM, silicon rubber, etc. excellent in heat resistance and chemical resistance. Can do. Here, the guide member 21 is not limited to the above-described synthetic rubber. For example, a thermoplastic synthetic resin such as PA (polyamide) 66 may be integrally joined by injection molding, but is the same as the seal member 20. By using synthetic rubber, the guide member 21 and the seal member 20 can be vulcanized and bonded at the same time, thereby improving processability and reducing costs.

  Furthermore, in this embodiment, the guide member 23 is integrally joined to the inner diameter 11b between the double row outer raceway surfaces 11a, 11a of the outer ring 11 by vulcanization adhesion. The guide member 23 is made of synthetic rubber such as NBR, and gradually protrudes inward in the radial direction from both ends toward the central portion, and its inclined surface is formed into an arcuate concave surface. The guide member 23 causes the grease flowing in the guide member 21 to flow toward the double-row outer rolling surfaces 11a and 11a as shown by the arrows in the figure, and the filled grease enters the bearing central portion. It is possible to prevent uneven distribution and to circulate grease effectively inside the bearing.

  The material of the guide member 23 is not limited to the synthetic rubber described above, and a thermoplastic synthetic resin such as PA66 may be integrally joined by injection molding. Other synthetic resins include thermoplastic synthetic resins called so-called engineering plastics such as PPA (polyphthalamide) and PBT (polybutylene terephthalate), polyphenylene sulfide (PPS), and polyether ether ketone (PEEK). ), A thermoplastic synthetic resin called a so-called super engineering plastic such as polyamideimide (PAI), a phenol resin (PF), an epoxy resin (EP), a polyimide resin (PI), or the like.

  Next, the structure of the connection ring 9 of FIG. 3 is shown using FIGS. The connecting ring 9 shown in FIG. 4 is formed in the shape of an end ring having a slit 24 at one place in the circumferential direction. As a result, the diameter of the connecting ring 9 can be easily increased when the connecting ring 9 is inserted, so that the insertion property of the connecting ring 9 into the inner ring 7 (8) is improved, and the assembly workability can be improved.

  The connecting ring 25 shown in FIG. 5A includes a cored bar 26 including a cylindrical part 26a and flanges 26b and 26b extending radially inward from both ends of the cylindrical part 26a, and a cylindrical part of the cored bar 26. A seal member 20 and a guide member 21 are integrally joined to the inner periphery of 26a by vulcanization adhesion.

  Here, a plurality of recesses 27 are formed in the collar portion 26 b of the core metal 26 at equal intervals in the circumferential direction. These recesses 27 are alternately formed, that is, staggered at both ends of the cylindrical portion 26a of the cored bar 26, as shown in FIG. And the recessed part 27 is formed in the shape by which the collar part 26b was excised. Thereby, it becomes easy to elastically deform at the time of insertion, and while maintaining the strength of the connecting ring 25, the insertability can be further improved and the assembly workability can be improved.

  The connecting ring 28 shown in FIG. 6 is formed in a ring shape having a slit 24 in one circumferential direction, and includes a cylindrical portion 29a and flanges 29b and 29b extending radially inward from both ends of the cylindrical portion 29a. And a seal member 20 and a guide member 21 that are integrally joined to the inner periphery of the cylindrical portion 29a of the core metal 29 by vulcanization adhesion.

  Here, a plurality of recesses 27 are formed in the collar portion 29 b of the core metal 29 at equal intervals in the circumferential direction. The recesses 27 are formed in a shape in which the flange portion 29b is cut out, and are formed in a staggered pattern alternately on the left and right sides of the cylindrical portion 29a of the core metal 29. Accordingly, the strength of the connecting ring 28 is maintained, and the elastic deformation is further facilitated at the time of insertion, and the insertion property is further improved and the assembling workability can be improved.

  Next, the modification of the guide member 21 of FIG. 3 is shown using FIG. The guide member 30 shown in (a) is integrally joined to the metal core 19 by vulcanization adhesion, and the cross section that protrudes radially outward from both ends of the metal core 19 toward the axial center is substantially triangular. Is formed. The guide member 31 shown in (b) has a pair of substantially triangular cross sections that project radially outward from the central portion of the core bar 19 toward both ends. The guide member 32 shown in (c) gradually protrudes radially outward from the central portion of the core bar 19 toward both ends, and its inclined surface is formed into an arcuate concave surface. The guide member 33 shown in (d) has a substantially semicircular cross section that protrudes radially outward from both ends of the core bar 19 toward the axial center. These guide members 30, 31, 32, and 33 are all formed in an annular shape and can prevent grease from being unevenly distributed in the center portion of the bearing. The flow direction of the grease can be appropriately controlled by the angle and shape of the slope and the protruding direction.

  Next, a modification of the guide member 23 shown in FIG. 3 will be described with reference to FIG. The guide member 34 shown in (a) is integrally joined to the inner periphery of the inner diameter 11b of the outer ring 11 by vulcanization adhesion. The guide member 34 is made of synthetic rubber such as NBR, and has a substantially triangular cross section that protrudes radially inward toward the axial center. A coating layer 34a made of a fluororesin is formed on the slope. As a result, the oil repellency is improved, and the fluidity can be enhanced by suppressing the retention and adhesion of grease.

  The guide member 35 shown in (b) gradually protrudes radially inward from both ends of the inner diameter 11b of the outer ring 11 toward the axially central portion, and its inclined surface is formed into an arcuate concave surface. The guide member 36 shown in (c) has a substantially semicircular cross section that protrudes radially inward from both ends of the inner diameter 11b toward the central portion in the axial direction. These guide members 34, 35, and 36 are all formed in an annular shape, and grease that has flowed due to the centrifugal force generated as the bearing rotates is caused to flow toward the outer rolling surface 11a, and the grease is centered on the bearing. It is possible to prevent uneven distribution in the part. The flow direction of the grease can be appropriately controlled by the angle and shape of the slope and the protruding direction.

  FIG. 9 is a longitudinal sectional view showing a second embodiment of the wheel bearing according to the present invention, and FIGS. 10A and 10B are enlarged views of main parts showing a modification of the guide member of FIG. . This embodiment is basically the same as the first embodiment (FIG. 2) described above except that the configuration of the outer ring is partially different. Are denoted by the same reference numerals, and detailed description thereof is omitted.

  The wheel bearing 37 shown in FIG. 9 is inserted into the outer ring 38 and formed on the outer ring 38 with an outer ring 38 formed with tapered double-row outer raceway surfaces 11a, 11a opened outward on the inner circumference, and the outer ring 38 A pair of inner rings 7, 8 formed with tapered inner rolling surfaces 7a, 7a facing the double row outer rolling surfaces 11a, 11a, and a double row rolling element 15 accommodated between both rolling surfaces. , 15 and a cage 16 for holding the rolling elements 15, 15 in a double row so as to roll freely.

  Here, in this embodiment, the outer ring 38 is made of high carbon chrome bearing steel such as SUJ2, and is hardened in the range of 58 to 64 HRC up to the core part by quenching. And the guide member 39 is integrally formed in the internal diameter 38a between the double row outer side rolling surfaces 11a of the outer ring | wheel 38, 11a. The guide member 39 gradually protrudes inward in the radial direction from both ends of the inner diameter 38a toward the central portion, and its inclined surface is formed into an arcuate concave surface. By this guide member 39, the filled grease can be prevented from being unevenly distributed in the center portion of the bearing, and the grease can be effectively circulated inside the bearing.

  10 (a) and 10 (b) show a modification of the guide member 39. FIG. The guide member 40 shown in (a) has a substantially triangular cross section that protrudes radially inward from both ends of the inner diameter 38a toward the central portion in the axial direction. And the coating layer 40a which consists of a fluororesin is formed in the slope. Thereby, the oil repellency of the guide member 40 becomes good, and the fluidity can be improved by suppressing the staying and adhesion of grease. The guide member 41 shown in (b) has a substantially semicircular cross section that protrudes radially inward from both ends of the inner diameter 38a toward the central portion in the axial direction.

  The embodiment of the present invention has been described above, but the present invention is not limited to such an embodiment, and is merely an example, and various modifications can be made without departing from the scope of the present invention. Of course, the scope of the present invention is indicated by the description of the scope of claims, and further, the equivalent meanings described in the scope of claims and all modifications within the scope of the scope of the present invention are included. Including.

  The wheel bearing device according to the present invention can be applied to a full floating type wheel bearing device on the side of a driving wheel in which wheel bearings are mounted in openings of a driving shaft and an axle tube.

1 Axle tube 2 Drive shaft 3, 37 Wheel bearing 4 Hub wheel 5 Hub bolt 6 Drive shaft flange 7 Outer side inner ring 7a Inner rolling surface 7b Large collar 7c Small collar 7d Inner ring front side end face 8 Inner side inner ring 9 , 25, 28 Connecting ring 10 Fixing nut 11, 38 Outer ring 11a Outer rolling surface 11b, 38a Inner diameter 12 of outer ring Brake rotor 13 Annular step 14 Seal ring 15 Rolling element 16 Retainer 17 Annular convex 17a Annular convex Wall surface 17b on the groove side Wall surface 18 on the end face side of the annular convex portion Seals 19, 26, 29 Core bars 19a, 26a, 29a Cylindrical portions 19b, 26b, 29b Hook portion 20 Seal member 20a Protruding portions 21, 23, 30, 31, 32, 33, 34, 35, 36, 40, 41 Guide member 22 Recess groove 24 Slit 27 Recess 34a, 40a Coating layer 51 Axle tube 52 Drive shaft 5 Wheel bearing 54 Hub wheel 55 Hub bolt 56 Drive shaft flange 57, 58 Inner ring 57a Inner ring end face 59 Connecting ring 60 Fixing nut 61 Outer ring 62 Brake rotor 63 Rolling element 64 Cage 65 Seal 66 Annular step 67 Seal ring 68 Annular convex Portions 68a, 68b Wall surface 69 Core 69a Cylindrical portion 69b Gutter 70 Seal member 70a Protruding portion 71 Annular groove d1 Inner diameter d2 of seal member Outer diameter D1 of outer groove D2 Outer diameter of annular convex part Diameter D3 Inner ring end outer diameter α Wall inclination angle

Claims (7)

An outer ring in which a double row outer rolling surface is integrally formed on the inner periphery;
A pair of inner rings formed on the outer periphery with an inner rolling surface facing the double row outer rolling surface;
A double row rolling element housed in a freely rolling manner between the rolling surfaces of the inner ring and the outer ring,
A seal mounted on both side openings of an annular space formed between the outer ring and the inner ring;
An annular convex portion is formed at the front side end of the inner ring, a connecting ring is attached to the annular convex portion, and the inner ring is integrally coupled,
A core metal of the connecting ring is formed in shape of a steel plate or al cross-section substantially U, comprising a cylindrical portion, a flange portion extending at both ends radially inward from the cylindrical portion,
This is joined to the inner periphery to one body of the cylindrical portion of the metal core, the wheel bearing apparatus provided with a sealing member made of synthetic rubber to be elastically contacted with an end portion of said inner ring,
An annular guide member is integrally joined to the outer periphery of the metal core, and the guide member has an inclined surface that gradually protrudes radially outward, and an inner diameter between double row outer rolling surfaces of the outer ring. A guide member made of synthetic rubber is integrally joined to each other, and the guide member has an inclined surface that gradually protrudes radially inward from both ends toward the axial central portion. .   An axle tube through which a drive shaft connected to the differential is inserted, and a hub wheel integrally having a wheel mounting flange for mounting a wheel on the outer periphery and connected to the flange of the drive shaft via a hub bolt, The outer ring is press-fitted into a hub wheel, and is fixed in an axial direction while being sandwiched between a flange of the drive shaft and a brake rotor, and the pair of inner rings are press-fitted into a shaft portion of the axle tube. The wheel bearing apparatus described in 1.   An annular concave groove is formed in the vicinity of the annular convex portion, the wall surface on the concave groove side of the annular convex portion is a substantially vertical surface, and the wall surface on the end surface side of the inner ring is a tapered surface having a predetermined inclination angle. The wheel bearing device according to claim 1, wherein the wheel bearing device is formed.   2. The wheel according to claim 1, wherein a plurality of recesses are formed at equal intervals in the collar portion of the core metal, and these recesses are formed in a staggered manner at both ends of the cylindrical portion of the core metal. Bearing device. The wheel bearing device according to claim 1 or 4 , wherein the cored bar is formed in an end ring shape having a slit in one circumferential direction. The wheel bearing device according to claim 1, wherein the guide member has a substantially triangular cross section. The wheel bearing device according to claim 1 or 6, wherein a coating layer made of a fluororesin is formed on a surface of the guide member.

Images