JP2008157327A - Bearing device for wheel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for a wheel, in which the service life of a bearing is elongated by enhancing sealing performance and durability of a seal. <P>SOLUTION: An outer side seal 8 is provided with a cored bar 12 and a seal member 13 which is vulcanized and bonded and is joined integrally with the cored bar 12. The cored bar 12 includes a fitting part 12a internally fitted in an outer member 2, an overlapped part 12b formed by bending outward in a diameter direction from the fitting part and abutted on an end surface 2c of the outer member 2, and an inner side part 12c extending inward in a diameter direction from the overlapped part. The seal member 13 includes a side lip 13a fixed on a range from an exposed part of the overlapped part 12b to the inner side part 12c, inclining outward in the diameter direction, and sliding on a base part 6b of a wheel mounting flange 6 through a predetermined interference, a dust lip 13b provided on an inner diameter side of the side lip and inclining outward in the diameter direction, and a grease lip 13c for forming a radial lip, and those are integrally formed. A maximum diameter of the side lip 13a is set to be an approximate outer diameter of the fitting part 12a. <P>COPYRIGHT: (C)2008,JPO&INPIT

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 specifically, to improve the sealing performance and durability of a seal mounted on a bearing portion, thereby extending the life of the bearing. The present invention relates to the wheel bearing device shown.

  2. Description of the Related Art Conventionally, a wheel bearing device for supporting a wheel of an automobile or the like supports a hub wheel for mounting a wheel rotatably via a double row rolling bearing, and includes a drive wheel and a driven wheel. For structural reasons, an inner ring rotation method is generally used for driving wheels, and an inner ring rotation method and an outer ring rotation method are generally used for driven wheels. Further, the wheel bearing device has a structure called a first generation in which a wheel bearing composed of a double row angular ball bearing or the like is fitted between a knuckle and a hub wheel constituting a suspension device. Second generation structure in which body mounting flange or wheel mounting flange is formed directly on the outer periphery of the member, third generation structure in which one inner rolling surface is directly formed on the outer periphery of the hub wheel, or hub wheel, etc. It is roughly classified into a fourth generation structure in which the inner rolling surface is directly formed on the outer periphery of the outer joint member of the speed universal joint.

  These bearing portions are fitted with seals to prevent leakage of grease sealed inside the bearings and to prevent intrusion of rainwater, dust and the like from the outside. In recent years, the maintenance of automobiles has become more maintenance-free, and even longer bearing life has been demanded for wheel bearing devices. However, the damage due to the sealing failure is a major factor. Therefore, the bearing life can be improved by increasing the sealing performance and durability of the seal.

  Conventionally, various seals with improved sealing performance have been proposed. An example of such a seal is shown in FIG. The seal 50 is mounted between an outer ring 51 having an outer rolling surface 51a formed on the inner periphery and a hub wheel 52 having an inner rolling surface 52a opposite to the outer rolling surface 51a. The outer end opening existing between the inner peripheral surface of 51 and the outer peripheral surface of the hub wheel 52 is closed. The seal 50 includes a cored bar 53 made of a metal plate such as a mild steel plate press-fitted into the inner peripheral surface of the outer ring 51, and a sealant 54 made of an elastic material such as an elastomer such as rubber, which is joined to the cored bar 53. Become. The seal material 54 includes three seal lips that are concentric with each other, that is, a side lip 55, a dust lip 56, and a grease lip 57.

  Of these three seal lips 55, 56, 57, the side lip 55 provided on the outermost diameter side is inclined in a direction positioned radially outwardly toward the tip edge, and the tip edge is The wheel mounting flange 58 provided on the outer peripheral surface of the hub wheel 52 is in sliding contact with a portion near the inner surface inner diameter of the wheel mounting flange 58 with a squeeze over the entire periphery.

  The dust lip 56 provided in the middle has a curved surface portion 60 provided at a connecting portion between the inner surface of the wheel mounting flange 58 and the outer peripheral surface of the hub wheel 52 with the leading edge facing away from the inner space 59. In addition, it is in sliding contact with a squealing over the entire circumference.

  Further, the grease lip 57 provided closest to the inner space 59 has a labyrinth gap 61 formed in close proximity to the outer peripheral surface of the hub wheel 52 with the leading edge directed toward the inner space 59. Since the labyrinth gap 61 is present near the inner diameter of the outer end opening of the internal space 59, the grease enclosed in the internal space 59 is caused by the centrifugal force applied with the rotation of the hub wheel 52. It tends to gather near the outer diameter of the space 59.

That is, when the hub wheel 52 rotates, the ball 62 and the cage 63 installed in the internal space 59 rotate at a rotational speed that is approximately ½ of the rotational speed of the hub wheel 52, and this rotation is transmitted to the grease. . As a result, this grease gathers near the outer diameter of the internal space 59, and there is almost no grease in the portion near the inner diameter where the labyrinth gap 61 exists. Therefore, in combination with the fact that the grease lip 57 is inclined in the direction toward the inner space 59 as it goes inward in the radial direction, the grease leaks out of the inner space 59 through the labyrinth gap 61. It is possible to prevent the rotation resistance of the hub wheel 52 and improve the running performance of the vehicle while ensuring the required sealing performance.
JP 2003-222145 A

  In such a conventional seal 50, grease leakage is effectively prevented by the labyrinth gap 61 of the grease lip 57, and the side lip 55 and the dust lip 56 which are inclined in the radially outward direction toward the distal end edge are used to Intrusion of rainwater, dust, etc. can be prevented. Here, in particular, the side lip 55 provided on the outermost diameter side has a more appropriate elastic force as the seal lip is lengthened, and extends to the inner surface inner diameter portion of the wheel mounting flange 58 over the entire circumference. It is known that the sealing performance is improved because the sliding contact is made with a uniform shimoshiro.

  However, if the length of the side lip 55 is increased, the outer diameter thereof is increased, and when the seal 50 is press-fitted into the outer ring 51, the press-fitting jig 64 interferes with the side lip 55 to cause damage. Therefore, in order to avoid interference with the side lip 55, for example, as shown in FIG. 6, it has a thin claw or the like that protrudes into a narrow annular space on the outer peripheral portion of the side lip 55 and presses the end face of the seal 50. A method of press-fitting using a simple press-fitting jig 64 has been adopted. In this case, the seal pressure input is insufficient, and when the internal pressure increases due to the temperature rise of the bearing, the seal 50 comes out, and there is a possibility that the original sealing performance cannot be obtained.

  The present invention has been made in view of such a conventional problem, and an object of the present invention is to provide a wheel bearing device in which the sealing performance and durability of a seal are enhanced to extend the life of the bearing.

  In order to achieve such an object, the invention according to claim 1 of the present invention has a vehicle body mounting flange integrally attached to the vehicle body on the outer periphery, and a double row outer rolling surface is formed on the inner periphery. An outer member, and a wheel mounting flange for mounting a wheel at one end are integrally formed, one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and an axis from the inner rolling surface Hub wheel formed with a small-diameter step portion extending in the direction, and an inner ring fitted with the small-diameter step portion of the hub wheel and having the other inner rolling surface facing the outer rolling surface of the double row on the outer periphery Alternatively, an inner member composed of an outer joint member of a constant velocity universal joint, a double row rolling element that is rotatably accommodated between both rolling surfaces of the inner member and the outer member, and the outer member A wheel shaft having a seal attached to an opening of an annular space formed between the inner member and the inner member In the apparatus, the seal on the outer side of the seal comprises a cored bar formed by pressing a steel plate, and a seal member integrally bonded to the cored bar by vulcanization adhesion, A cylindrical fitting portion that is fitted on the inner periphery of the outer end of the outer member, and is formed by bending outward from the fitting portion in the radial direction, and contacts the outer end surface of the outer member. And an inner portion extending radially inward from the overlapping portion, and the seal member is inclined outward in the radial direction toward the tip, and the base portion on the inner side of the wheel mounting flange The side lip that is slidably contacted via a predetermined shimiro is integrally formed, and the maximum diameter of the side lip is set to be substantially the outer diameter of the fitting portion of the metal core.

  As described above, in the wheel bearing device having the hub wheel having the wheel mounting flange at one end and the inner raceway surface formed directly on the outer periphery, the outer seal of the seals presses the steel plate. A cylindrical fitting in which the cored bar is fitted into the inner periphery of the outer end of the outer member. An overlapping portion formed by bending radially outward from the fitting portion and being in contact with the outer end surface of the outer member, and an inner portion extending radially inward from the overlapping portion. In addition, the seal member integrally has a side lip that inclines outward in the radial direction toward the tip and slidably contacts with the base portion on the inner side of the wheel mounting flange via a predetermined shimoshiro. Is set to approximately the outer diameter of the fitting part of the cored bar Enough space between the maximum diameter of the maximum diameter and the side lip of the seal can be secured, a seal stuffing jig without interfering with the side lip can be easily pressed into the outer member. Therefore, sufficient pressure input of the seal can be ensured, and even when the internal pressure increases due to the temperature rise of the bearing, the seal can be prevented from coming out and the original sealing performance can be exhibited.

  Preferably, as in the invention described in claim 2, the base portion is formed in an arc shape in cross section, and the outer side seal is provided on the inner diameter side of the side lip, and the outer side in the radial direction toward the tip. And a radial lip with the tip edge facing the inner side of the bearing, and a dust lip formed at a different inclination angle and length from the side lip and slidably contacted with the base via a predetermined shimoshiro If the grease lip is provided, it is possible to effectively prevent leakage of grease sealed inside the bearing and intrusion of rainwater, dust, and the like from the outside into the bearing.

  Further, as in the invention described in claim 3, if the sealing member includes an enveloping portion that covers the overlapping portion of the core metal, rusting of the core metal is prevented and airtightness of the seal fitting portion is achieved. And the sealing performance and durability of the seal can be improved.

  According to a fourth aspect of the present invention, a belt-like protrusion is formed on the outer diameter side of the side lip, and this protrusion faces the side surface of the wheel mounting flange via a predetermined axial clearance. If the labyrinth seal is configured, foreign matter from the outside can be prevented from directly entering the side lip, and the sealing performance and durability of the seal can be further enhanced.

  Moreover, if the said core metal is formed from the steel plate which has rust prevention ability like invention of Claim 5, the rusting of a core metal can be prevented reliably over a long period of time.

  A wheel bearing device according to the present invention has a vehicle body mounting flange integrally attached to the vehicle body on the outer periphery, an outer member having a double row outer raceway formed on the inner periphery, and a wheel on one end. A wheel mounting flange is integrally formed, and one inner rolling surface facing the outer rolling surface of the double row is formed on the outer periphery, and a small diameter step portion extending in the axial direction from the inner rolling surface is formed. Outer ring member of an inner ring or a constant velocity universal joint that is fitted to a small diameter step portion of the hub ring and has the other inner rolling surface facing the outer rolling surface of the double row on the outer periphery. Formed between the outer member and the inner member, a double row rolling element housed between the rolling surfaces of the inner member and the outer member so as to roll freely. In a wheel bearing device comprising a seal attached to an opening of the annular space, the seal The outer side seal is composed of a cored bar formed by pressing a steel plate and a seal member integrally bonded to the cored bar by vulcanization adhesion, and the cored bar is an outer member of the outer member. A cylindrical fitting portion that is fitted inside the inner periphery of the end portion, and a superposed portion that is formed by bending outward from the fitting portion in the radial direction and is in contact with the outer end surface of the outer member; And an inner portion extending radially inward from the overlapping portion, and the seal member is inclined radially outward as it goes to the tip, and a predetermined shimiro is placed on the base portion on the inner side of the wheel mounting flange. Since the side lip that is in sliding contact is integrally formed and the maximum diameter of the side lip is set to be substantially the outer diameter of the fitting portion of the core metal, the gap between the maximum diameter of the seal and the maximum diameter of the side lip Sufficient space can be secured for the side lip It can be easily pressed into the outer member a seal stuffing jig without Wataru. Therefore, sufficient pressure input of the seal can be ensured, and even when the internal pressure increases due to the temperature rise of the bearing, the seal can be prevented from coming out and the original sealing performance can be exhibited.

  A body mounting flange for mounting to the vehicle body on the outer periphery, an outer member having a double row outer raceway formed on the inner periphery, and a wheel mounting flange for mounting a wheel on one end are integrated. A hub wheel having one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, a small diameter step portion extending in the axial direction from the inner rolling surface, and a small diameter of the hub wheel An inner member comprising an inner ring that is press-fitted into the step portion through a predetermined shimoshiro and has the other inner rolling surface opposed to the outer rolling surface of the double row on the outer periphery; the inner member and the outer member A double row of balls accommodated between both rolling surfaces of the side member, and a seal attached to an opening of an annular space formed between the outer member and the inner member. In the wheel bearing device, the outer seal of the seals presses the steel plate. A cylinder formed by a core and a seal member integrally joined to the core by vulcanization adhesion, and the core is fitted into the inner periphery of the outer end of the outer member A fitting portion, a bent portion that is bent radially outward from the fitting portion, and is in contact with the outer end surface of the outer member, and a radially inward direction from the overlapping portion. An inner portion extending, and the seal member is fixed in a range extending from the exposed portion of the overlapping portion of the core metal to the inner end portion of the inner portion, and is inclined radially outward toward the tip, A side lip that is in sliding contact with a base portion on the inner side of the wheel mounting flange via a predetermined shimiro, and provided on the inner diameter side of the side lip, is inclined radially outward toward the tip, and is different from the side lip. The base is formed with an inclination angle and a length, and a predetermined shishiro And a grease lip constituting a radial lip with the tip edge directed toward the inner side of the bearing, and the maximum diameter of the side lip is an abbreviation of the fitting portion of the cored bar. The outer diameter is set.

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 first embodiment of a wheel bearing device according to the present invention, and FIG. 2 is an enlarged view of a main part of FIG. In the following description, the side closer to the outer side of the vehicle in a state assembled to the vehicle is referred to as the outer side (left side in the drawing), and the side closer to the center is referred to as the inner side (right side in the drawing).

  This wheel bearing device is for a drive wheel called the third generation, and is a double row rolling element housed in a freely rollable manner between the inner member 1, outer member 2, and both members 1,2. (Balls) 3 and 3. The inner member 1 includes a hub ring 4 and an inner ring 5 press-fitted into the hub ring 4 through a predetermined shimiro.

  The hub wheel 4 integrally has a wheel mounting flange 6 for mounting a wheel (not shown) at an end portion on the outer side, and has one (outer side) inner rolling surface 4a on the outer periphery and the inner rolling surface. A cylindrical small diameter step portion 4b extending in the axial direction from the surface 4a is formed, and a serration (or spline) 4c for torque transmission is formed on the inner periphery. In addition, hub bolts 6a are planted on the wheel mounting flange 6 in the circumferential direction.

  The inner ring 5 is formed with the other (inner side) inner raceway surface 5a on the outer periphery, and is press-fitted into the small-diameter step portion 4b of the hub ring 4 through a predetermined shimiro to form a back-to-back type double-row angular ball bearing. is doing. The inner ring 5 and the rolling element 3 are made of high carbon chrome steel such as SUJ2, and are hardened in the range of 58 to 64 HRC to the core part by quenching.

  The hub wheel 4 is formed of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the inner raceway surface 4a and the base portion 6b on the inner side of the wheel mounting flange 6 are connected to the small diameter step portion 4b. Thus, the surface hardness is set to a range of 58 to 64 HRC by induction hardening.

  The outer member 2 integrally has a vehicle body mounting flange 2b to be attached to a knuckle (not shown) on the outer periphery, and the inner rolling surface 4a of the hub wheel 4 and the inner rolling surface 5a of the inner ring 5 on the inner periphery. Double row outer rolling surfaces 2a, 2a facing each other are integrally formed. Double-row rolling elements 3 and 3 are accommodated between these rolling surfaces and are held by the cages 7 and 7 so as to be freely rollable.

  This outer member 2 is made of medium and high carbon steel containing 0.40 to 0.80 wt% of carbon such as S53C, and the double row outer rolling surfaces 2a and 2a have a surface hardness of 58 to 64HRC by induction hardening. Has been cured. Further, seals 8 and 9 are attached to the opening of the annular space formed between the outer member 2 and the inner member 1. The inner seal 9 forms a so-called pack seal composed of a slinger 10 and an annular seal plate 11. Along with the outer seal 8 to be described later, leakage of grease sealed inside the bearing and prevention of rainwater, dust and the like from entering the bearing from the outside are prevented. In addition, although the double row angular contact ball bearing which used the ball for the rolling element 3 was illustrated here, not only this but the double row tapered roller bearing which uses the tapered roller for the rolling element 3 may be sufficient. Further, the structure is not limited to the third generation structure on the drive wheel side, and may be a structure in which the inner rolling surface is directly formed on the hub wheel. For example, a fourth generation structure may be used.

  Here, the outer seal 8 includes a cored bar 12 and a seal member 13 integrally joined to the cored bar 12 by vulcanization adhesion, as shown in an enlarged view in FIG. The core metal 12 is formed by pressing a steel plate such as a cold rolled steel plate (JIS standard SPCC system or the like). The cored bar 12 is formed by a cylindrical fitting part 12a fitted inside the inner periphery of the end part of the outer member 2, and bent outward in the radial direction from the fitting part 12a. The overlapping portion 12b is in contact with the end surface 2c, and the inner portion 12c extends radially inward from the overlapping portion 12b.

  On the other hand, the seal member 13 is made of synthetic rubber such as nitrile rubber, and is fixed to a range extending from the exposed portion of the overlapping portion 12b of the core metal 12 to the inner end portion of the inner portion 12c, and the side lip 13a, the dust lip 13b, It has a grease lip 13c and a surrounding part 13d. The base 6b of the wheel mounting flange 6 is formed in a curved surface having an arc-shaped cross section, and the side lip 13a and the dust lip 13b are inclined outward in the radial direction toward the tip, and have different inclination angles and lengths. Is formed. The entire circumference of the base portion 6b is in sliding contact with a predetermined shimiro. Further, the grease lip 13c constitutes a radial lip with the tip edge facing the inner side of the bearing, and is in sliding contact with the outer peripheral surface of the base portion 6b via a predetermined nip.

  In this embodiment, the overlapping portion 12b protruding radially outward from the fitting portion 12a is formed on the core metal 12, and the maximum diameter of the side lip 13a is set to the substantially outer diameter of the fitting portion 12a of the core metal 12. Therefore, a sufficient space can be ensured between the maximum diameter of the seal 8 and the maximum diameter of the side lip 13a, and the seal 8 is attached by a press-fitting jig (not shown) without interfering with the side lip 13a. The outer member 2 can be easily press-fitted. Therefore, the pressure input of the seal 8 can be sufficiently secured, and even when the internal pressure increases due to the temperature rise of the bearing, the seal 8 can be prevented from coming out and the original sealing performance can be exhibited. Furthermore, since the exposed portion of the overlapping portion 12b is covered by the surrounding portion 13d of the seal member 13, the rusting of the cored bar 12 is prevented, and the airtightness of the seal fitting portion is enhanced, and the seal 8 is sealed. And can increase durability.

  FIG. 3 is an enlarged view showing a main part of a second embodiment of the wheel bearing device according to the present invention. Note that this embodiment is basically different from the first embodiment described above in that the seal member configuration is only partially different, and other parts and parts having the same function or the same function as the first embodiment. Are denoted by the same reference numerals and detailed description thereof is omitted.

  The outer-side seal 14 includes a cored bar 12 and a seal member 15 joined to the cored bar 12 by vulcanization adhesion. The seal member 15 is made of synthetic rubber such as nitrile rubber, and is fixed in a range extending from the exposed portion of the overlapping portion 12b of the cored bar 12 to the inner end portion of the inner portion 12c. The side lip 13a, the dust lip 13b, and the grease lip 13c and a belt-like protrusion 15a are formed on the outer diameter side of the side lip 13a. The projecting portion 15a is opposed to the side surface of the wheel mounting flange 6 via a predetermined axial clearance to form a labyrinth seal 16. This prevents foreign matter from entering the side lip 13a directly, and the sealing performance and durability of the seal 14 are further enhanced.

  FIG. 4 is an enlarged view of a main part showing a third embodiment of the wheel bearing device according to the present invention. This embodiment is basically different from the first embodiment described above only in the configuration of the seal, and other parts and parts having the same parts or the same functions as the first embodiment have the same reference numerals. The detailed description is omitted.

  The outer-side seal 17 includes a cored bar 18 and a seal member 19 that is integrally joined to the cored bar 18 by vulcanization adhesion. The metal core 18 is made of a material different from that of the first embodiment described above, such as an austenitic stainless steel plate (JIS standard SUS304 type or the like), a rust-proof cold rolled steel plate (JIS standard SPCC type or the like), or the like. The steel plate having corrosion resistance is formed by press working. The cored bar 18 is formed by a cylindrical fitting part 18a fitted in the inner periphery of the end part of the outer member 2, and bent outward in the radial direction from the fitting part 18a. The overlapping portion 18b is in contact with the end surface 2c, and the inner portion 18c extends radially inward from the overlapping portion 18b.

  On the other hand, the seal member 19 is made of synthetic rubber such as nitrile rubber, and is fixed to the inner end portion of the inner portion 18c of the cored bar 18 and has a side lip 13a, a dust lip 13b, and a grease lip 13c. In the present embodiment, the cored bar 18 is formed of a steel plate having rust prevention ability, so that the rusting of the cored bar 18 can be reliably prevented over a long period of time, and the seal 17 Sealability and durability can be improved.

  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 wheel bearing device having a third or fourth generation structure in which an inner rolling surface is directly formed on a hub wheel, regardless of whether it is for driving wheels or driven wheels. it can.

It is a longitudinal section showing a 1st embodiment of a bearing device for wheels concerning the present invention. It is a principal part enlarged view of FIG. It is a principal part enlarged view which shows 2nd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows 3rd Embodiment of the wheel bearing apparatus which concerns on this invention. It is a principal part enlarged view which shows the seal | sticker of the conventional wheel bearing apparatus. It is explanatory drawing which shows the press injection method of the seal | sticker of FIG.

Explanation of symbols

1 .... Inner member 2 ... Outer member 2a ... Outer rolling surface 2b ... ··· Body mounting flange 2c ··· Outer end surface 3 ··········· Rolling element 4 ··· Hub wheel 4a, 5a ... Inside rolling surface 4b ... Small diameter step 4c ... Serration 5 ... .... Inner ring 6 ..... Wheel mounting flange 6a ..... Hub bolt 6b ..... Base 7 ... ········· Retainer 8, 14, 17 ··· Outer side seal 9 ······· Inner side seal 10 ··· Slinger 11 ... Seal plates 12, 18 ... .... Cores 12a, 18a ... Fitting parts 12b, 18b ... Polymerized parts 12c, 18c ... Inner parts 13, 15, 19 ... Seal member 13a ...・ ・ ・ ・ ・ ・ Side lip 13b ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ Dustrip 13c ・ ・ ・ ・ ・ ・ ・ ・ Grease lip 15a ・ ・ ・ ・ ・ ・ ・ ・ Enclosure 16 ・ ・ ・... Labyrinth seal 50 ... Outer side seal 51 ... Outer member 51a ... Outer rolling surface 52 ... hub wheel 52a ... inner rolling surface 53 ... cored bar 54 ...・ Sealant 55 ... Side lip 56 ... Dustrip 57 ... Grease lip 58 ... ··· Wheel mounting flange 59 ··· Internal space 60 ··· Curved surface portion 61 ··· Labyrinth gap 62 · · ·・ ・ ・ ・ ・ ・ ・ ・ ・ Ball 63 ・ ・ ・ ・ ・ ・ Cage 64

Claims (5)

An outer member integrally having a vehicle body mounting flange for mounting to the vehicle body on the outer periphery, and a double row outer rolling surface formed on the inner periphery;
A wheel mounting flange for mounting a wheel at one end is integrally formed, one inner rolling surface facing the outer rolling surface of the double row on the outer periphery, and a small diameter step extending in the axial direction from the inner rolling surface A hub ring formed with a portion, and an inner ring or constant velocity universal joint that is fitted to the small-diameter step portion of the hub ring and has the other inner rolling surface facing the outer rolling surface of the double row on the outer periphery. An inner member made of an outer joint member of
A double row rolling element housed so as to be freely rollable between both rolling surfaces of the inner member and the outer member;
In a wheel bearing device comprising a seal mounted in an opening of an annular space formed between the outer member and the inner member,
The seal on the outer side of the seal is composed of a cored bar formed by pressing a steel plate, and a seal member integrally joined to the cored bar by vulcanization adhesion, and the cored bar is the outer side A cylindrical fitting portion that is fitted in the inner periphery of the outer end portion of the member, and is formed by bending outward in the radial direction from the fitting portion, and is in contact with the outer end surface of the outer member. A superposition part and an inner part extending radially inward from the superposition part, and the seal member is inclined outward in the radial direction toward the tip, and a predetermined part is provided on a base part on the inner side of the wheel mounting flange. A wheel bearing device comprising a side lip that is slidably contacted through a shimiro, and the maximum diameter of the side lip is set to be substantially the outer diameter of the fitting portion of the cored bar.   The base is formed in an arcuate cross section, and the outer side seal is provided on the inner diameter side of the side lip, and is inclined outward in the radial direction toward the tip, and has an inclination angle different from that of the side lip. The dust lip which is formed in length and is in sliding contact with the base portion via a predetermined shimiro, and a grease lip which forms a radial lip with a tip edge facing the inner side of the bearing. Wheel bearing device.   The wheel bearing device according to claim 1, wherein the seal member includes an enclosing portion that covers the overlapping portion of the cored bar.   4. A band-shaped protrusion is formed on the outer diameter side of the side lip, and the protrusion faces the side surface of the wheel mounting flange via a predetermined axial clearance to form a labyrinth seal. The wheel bearing apparatus in any one.   The wheel bearing device according to any one of claims 1 to 4, wherein the core metal is formed of a steel plate having antirust performance.

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