Wheel bearing device

Abstract

To provide a wheel bearing device capable of simplifying grinding work on a hub wheel.SOLUTION: In a wheel bearing device 1, a hub wheel 3 has an inner track groove 3c, a seal land part 3d, a recessed part 3m located on an outer diameter side of the seal land part 3d, and a flange face 3k located on an outer diameter side of the recessed part 3m, and an outer side seal member 10 includes a core metal 11 and a seal member 12. The seal member 12 has a contact lip 12d coming in contact with the seal land part 3d, and a labyrinth lip 12e opposed to the recessed part 3m on an outer diameter side of the contact lip 12d with a gap therebetween. The recessed part 3m has a bottom portion 313 located between an outer diameter side edge portion 311 and an inner diameter side edge portion 312 of the recessed part 3m, and a tapered surface 314 extending in a radial direction from the outer diameter side edge portion 311 toward the bottom portion 313 side and inclined toward one end side in an axial direction from the outer diameter side edge portion 311 toward the bottom portion 313.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a wheel bearing device. [Background technology]

[0002] A wheel bearing device that rotatably supports a wheel in a suspension system of an automobile, etc. is known. The wheel bearing device is provided with a sealing device that closes an open end of an annular space formed by an outer member and an inner member to prevent foreign matter such as muddy water from entering.

[0003] For example, in the wheel bearing device described in Patent Document 1, the hub ring, which is the inner member, has a hub flange extending radially outward, a sliding surface against which the main lip of the sealing device slides is formed at the base end of the hub flange, and a recess is formed on the outer diameter side of the sliding surface of the hub flange. A side lip of the sealing device faces the recess of the hub flange without contacting it, and a labyrinth seal is formed by the recess and the side lip, improving the muddy water resistance of the sealing device.

[0004] In this case, the flange surface located radially outward of the recess in the hub flange and the recess are formed by turning, and the sliding surface is formed by grinding. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2013-61048 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, since the recess has a U-shape and the outer diameter edge of the recess is formed on a surface perpendicular to the radial direction, when the hub flange is ground from the outer diameter side to the inner diameter side, it is difficult for the turning tool used to cut the flange surface to penetrate from the outer diameter side to the outer peripheral edge of the recess.

[0007] Therefore, when turning the hub flange, it is necessary to first turn the flange surface that is on the outer diameter side of the recess, then change the turning tool to one suitable for turning the outer edge of the recess, and then turn the recess, which makes the grinding work of the hub wheel complicated.

[0008] The present invention has been made in consideration of the above-mentioned circumstances, and provides a wheel bearing device which, when performing turning processing on a hub flange, can perform turning processing on the outer diameter side of the recessed portion and then continue to perform turning processing on the recessed portion without changing the turning tool, thereby simplifying the grinding processing work of the hub wheel. [Means for solving the problem]

[0009] That is, the wheel bearing device is provided with an outer member having double row outer raceway grooves on its inner circumference, a hub ring having a hub flange extending radially outward at one axial end and having a small diameter step extending axially on its outer circumference, and an inner member having double row inner raceway grooves facing the double row outer raceway grooves, double row rolling elements accommodated in a rollable manner between the raceway grooves of the outer member and the inner member, and a sealing device closing an opening end on one axial end side of an annular space formed by the outer member and the inner member, wherein the hub ring has the inner raceway grooves, a seal land portion located at a base end of the hub flange with which the sealing device is in sliding contact, and a recessed portion located on the outer diameter side of the seal land portion in the hub flange. and a flange surface located on the outer diameter side of the recess in the hub flange, the sealing device comprising a core bar fitted to one axial end of the outer member, and a seal member integrally joined to the core bar, the seal member having a contact lip extending from the core bar towards the hub flange and in contact with the seal land portion, and a labyrinth slip extending from the core bar towards the hub flange on the outer diameter side of the contact lip and facing the recess with a gap in the axial direction, the recess being located between an outer diameter side edge and an inner diameter side edge of the recess and having a bottom portion where the depth of the recess is greatest, and a tapered surface extending from the outer diameter side edge towards the bottom side in the radial direction and inclining towards one axial end side as it moves from the outer diameter side edge to the bottom portion. The hub wheel has a heat-treated portion that is hardened at least within an area in which the inner raceway groove, the seal land portion, and the recess are formed, and an outer peripheral edge of the heat-treated portion on the outer diameter side is located on the outer diameter side of the bottom of the recess and is located on the inner diameter side of the outer diameter side edge of the recess. . Effect of the Invention

[0010] According to the present invention, the grinding process for the hub wheel can be simplified. [Brief description of the drawings]

[0011] [Figure 1] 1 is a side cross-sectional view showing a wheel bearing device. [Diagram 2] 4 is a side cross-sectional view showing an outer seal member and a base end portion of a wheel mounting flange of a hub wheel. FIG. [Diagram 3]3 is a partial cross-sectional view of the hub wheel as viewed from the inner side in the axial direction. FIG. [Figure 4] FIG. 4 is a side cross-sectional view showing the inclination angle of a tapered surface in a recess of a wheel mounting flange. [Diagram 5] 10 is a side cross-sectional view showing how an inner diameter side edge of a recess in a wheel mounting flange protrudes further inward than an outer diameter side edge of the recess. FIG. [Figure 6] 13 is a side cross-sectional view showing a state in which the outer peripheral edge of the heat treatment portion is located on the outer diameter side of the bottom of the recess of the wheel mounting flange. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0013] [Wheel bearing device] A wheel bearing device 1 shown in FIG. 1 is one embodiment of a wheel bearing device according to the present invention, and supports a wheel rotatably in a suspension system of a vehicle such as an automobile.

[0014] The wheel bearing device 1 has a configuration referred to as the third generation, and includes an outer ring 2 as an outer member, a hub ring 3 and an inner ring 4 as inner members, two rolling rows consisting of an inner ball row 5 and an outer ball row 6, an inner seal member 9 and an outer seal member 10.

[0015] Here, the inner side refers to the vehicle body side of the wheel support bearing device 1 when it is attached to the vehicle body, and the outer side refers to the wheel side of the wheel support bearing device 1 when it is attached to the vehicle body. Also, the axial direction refers to the direction along the rotation axis of the wheel support bearing device 1, with one axial end side being the outer side and the other axial end side being the inner side.

[0016] An inner side opening 2a is formed at the inner side end of the outer ring 2, into which an inner side seal member 9 can be fitted. An outer side opening 2b is formed at the outer side end of the outer ring 2, into which an outer side seal member 10 can be fitted. An inner side outer raceway groove 2c and an outer side outer raceway groove 2d are formed on the inner circumferential surface of the outer ring 2.

[0017] A vehicle body mounting flange 2e for mounting the outer ring 2 to a vehicle body member is integrally formed on the outer peripheral surface of the outer ring 2. The vehicle body mounting flange 2e is provided with bolt holes 2g into which fastening members (here, bolts) for fastening the outer ring 2 to the vehicle body member are inserted.

[0018] The inner end of the outer circumferential surface 3j of the hub wheel 3 is formed with a small diameter step 3a that is smaller in diameter than the outer end. A shoulder 3e is formed at the outer end of the small diameter step 3a of the hub wheel 3. A wheel mounting flange 3b for mounting a wheel is formed integrally with the outer end of the hub wheel 3. A plurality of bolt holes 3f are formed in the wheel mounting flange 3b. Hub bolts 3i for fastening the hub wheel 3 to a wheel or a brake component are press-fitted into the bolt holes 3f. The wheel mounting flange 3b is an example of a hub flange that extends radially outward.

[0019] An outer peripheral surface 3j of the hub wheel 3 is provided with an outer-side inner raceway groove 3c facing the outer-side outer raceway groove 2d of the outer ring 2. In other words, the inner raceway groove 3c is formed by the hub wheel 3 on the outer side of the inner member. The outer seal member 10 is fitted into the outer-side opening end of the annular space formed by the outer ring 2 and the hub wheel 3, and closes the outer-side opening end. The outer seal member 10 is an example of a sealing device.

[0020] A seal land 3d with which the outer seal member 10 slides is formed at the base end of the inner side of the wheel mounting flange 3b. The inner raceway groove 3c is located adjacent to the inner side of the seal land 3d in the axial direction. The wheel mounting flange 3b has a flange surface 3k that faces the inner side. The flange surface 3k is located on the outer diameter side of the seal land 3d.

[0021] A recess 3m is formed on the inner side surface of the wheel mounting flange 3b between the flange surface 3k and the seal land portion 3d. The recess 3m is formed in a groove shape recessed from the inner side surface of the wheel mounting flange 3b to the outer side. The hub wheel 3 has an outer side end surface 3g at an end portion on the outer side than the wheel mounting flange 3b.

[0022] An inner ring 4 is provided on the small diameter step 3a of the hub ring 3. The inner ring 4 is fixed to the small diameter step 3a of the hub ring 3 by press fitting and crimping. The inner ring 4 applies preload to the inner ball row 5 and the outer ball row 6, which are the rolling rows. The inner ring 4 has an inner end face 4b at its inner end, and an outer end face 4c at its outer end. A crimped portion 3h is formed at the inner end of the hub ring 3, which is crimped to the inner end face 4b of the inner ring 4.

[0023] An inner-side inner raceway groove 4a is provided on the outer peripheral surface of the inner ring 4 so as to face the inner-side outer raceway groove 2c of the outer ring 2. In other words, the inner raceway groove 4a is defined by the inner ring 4 on the inner side of the inner member.

[0024] The inner ball row 5 and outer ball row 6, which are rolling rows, are formed by a plurality of balls 7, which are rolling elements, being held by a cage 8. The inner ball row 5 is rollably sandwiched between the inner raceway groove 4a of the inner ring 4 and the outer raceway groove 2c on the inner side of the outer ring 2. The outer ball row 6 is rollably sandwiched between the inner raceway groove 3c of the hub ring 3 and the outer raceway groove 2d on the outer side of the outer ring 2. In other words, the inner ball row 5 and the outer ball row 6 are rollably housed between the raceway grooves of the outer member and the inner member.

[0025] In the wheel bearing device 1, a double-row angular ball bearing is formed by the outer ring 2, hub ring 3, inner ring 4, inner ball row 5, and outer ball row 6. Note that the wheel bearing device 1 may be formed as a double-row tapered roller bearing instead of the double-row angular ball bearing.

[0026] [Outer seal material] As shown in FIG. 2, the outer seal member 10 includes a core metal 11 that is fitted to the inner circumference of the outer end portion of the outer ring 2 , and a seal member 12 that is joined integrally to the core metal 11 .

[0027] The core metal 11 is made of, for example, a steel plate, and has a cylindrical fitting portion 11a that fits into the inner circumference of the outer opening 2b of the outer ring 2, an inner portion 11b that extends from the inner end of the fitting portion 11a toward the inner diameter side, an outer portion 11c that extends from the outer end of the fitting portion 11a toward the outer diameter side, and an outer edge portion 11d that extends from the outer diameter end of the outer portion 11c toward the inner side.

[0028] The inner portion 11b is bent from the inner end of the fitting portion 11a, extends toward the outer side, then extends toward the inner diameter side, and further extends toward the inner side and the inner diameter side, and then extends toward the inner diameter side. The outer edge portion 11d extends toward the inner side with a predetermined gap between it and the outer peripheral surface 2h of the outer ring 2.

[0029] The seal member 12 is made of an elastic material such as synthetic rubber, and is bonded to the core metal 11 by vulcanization adhesion. The seal member 12 has a base portion 12a, a radial lip 12b, a first contact lip 12c, a second contact lip 12d, a labyrinth lip 12e, and a dam portion 12f. The base portion 12a is bonded to the core metal 11 in a range from the inner portion 11b to the outer edge portion 11d via the fitting portion 11a and the outer portion 11c.

[0030] The radial lip 12b is located at the inner diameter side end of the seal member 12 and extends radially inward and toward the inner side from the inside portion 11b of the core metal 11. The radial lip 12b is in sliding contact with the outer circumferential surface 3j of the hub wheel 3 via an oil film of grease.

[0031] The first contact lip 12c extends from the inner portion 11b of the core metal 11 toward the wheel mounting flange 3b and radially outward on the outer diameter side of the radial lip 12b. The first contact lip 12c is in sliding contact with the seal land portion 3d via a grease film. The first contact lip 12c is an example of a contact lip that contacts the seal land portion 3d.

[0032] The second contact lip 12d extends from the inner portion 11b of the core metal 11 toward the wheel mounting flange 3b and radially outward on the outer diameter side of the first contact lip 12c. The second contact lip 12d is in sliding contact with the seal land portion 3d via a grease film. The second contact lip 12d has a contact portion 121 on the tip side that is in sliding contact with the seal land portion 3d. The second contact lip 12d is an example of a contact lip that is in contact with the seal land portion 3d.

[0033] In this embodiment, the seal member 12 of the outer seal member 10 has a first contact lip 12c and a second contact lip 12d, and thus has a plurality of contact lips. However, the seal member 12 may have one contact lip or three or more contact lips. In this way, by configuring the seal member 12 to have one contact lip or two or more contact lips, the range of specifications of the seal member 12 that can be applied to the wheel bearing device 1 can be expanded, and versatility can be improved.

[0034] The labyrinth slip 12e extends from the outer portion 11c of the core 11 toward the wheel mounting flange 3b on the outer diameter side of the second contact lip 12d. The labyrinth slip 12e faces the recess 3m of the wheel mounting flange 3b with a gap in the axial direction. The labyrinth slip 12e is an example of a labyrinth slip that faces a recess with a gap in the axial direction.

[0035] A labyrinth seal is formed by the labyrinth slip 12e of the seal member 12 and the recess 3m of the wheel mounting flange 3b. The labyrinth seal is formed by the labyrinth slip 12e and the recess 3m, which prevents foreign matter such as muddy water from entering the inside of the outer seal member 10.

[0036] The dam portion 12f covers the outer edge portion 11d of the core metal 11, protrudes radially outward from the outer peripheral surface 2h of the outer ring 2, and is in contact with the outer peripheral surface 2h of the outer ring 2.

[0037] [Hub wheel] 2, in the wheel mounting flange 3b of the hub wheel 3, the flange surface 3k, the recess 3m, and the seal land portion 3d are located in this order from the outer diameter side to the base end side. That is, in the wheel mounting flange 3b, the recess 3m is located on the outer diameter side of the seal land portion 3d, and the flange surface 3k is located on the outer diameter side of the recess 3m. Also, the inner raceway groove 3c is located on the inner side and inner diameter side of the seal land portion 3d.

[0038] In the hub wheel 3, the flange surface 3k, the recess 3m, the seal land portion 3d, and the inner raceway groove 3c are machined using a turning tool, and after the machined portion, the seal land portion 3d and the inner raceway groove 3c are further ground using a grinding wheel.

[0039] When performing the turning process on the hub ring 3, the flange surface 3k is machined from the outer diameter side to the inner diameter side, then the recess 3m is machined, and then the seal land 3d and the inner raceway groove 3c are machined in that order. When performing the grinding process on the hub ring 3, a grinding wheel is used to simultaneously grind the seal land 3d and the inner raceway groove 3c.

[0040] Since the turning and grinding processes are performed in this manner on the hub ring 3, the flange surface 3k and the recess 3m have turned surfaces, and the seal land 3d and the inner raceway groove 3c have ground surfaces. Note that, for example, the recess 3m of the hub ring 3 can be subjected to post-processing such as shot blasting after turning. If the recess 3m is subjected to shot blasting, the recess 3m will have a blasted surface.

[0041] As shown in Figures 2 and 3, the recess 3m is formed in a circular groove shape extending along the circumferential direction, and has an outer diameter side edge 311 that is the boundary between the flange surface 3k and the recess 3m, an inner diameter side edge 312 that is the boundary between the recess 3m and the seal land portion 3d, and a bottom 313 that is located between the outer diameter side edge 311 and the inner diameter side edge 312 in the radial direction and has the greatest axial depth of the recess 3m.

[0042] The inner diameter side edge 312 of the recess 3m is located on the outer diameter side of the contact portion 121 with the seal land portion 3d of the second contact lip 12d that is located on the outer diameter side among the contact lips of the seal member 12. In this case, the inner diameter side edge 312 of the recess 3m is preferably located 1 mm or more on the outer diameter side of the contact portion 121 of the second contact lip 12d. In other words, in the radial direction, the separation distance L1 between the inner diameter side edge 312 and the contact portion 121 is preferably 1 mm or more.

[0043] In this way, since the inner diameter side edge 312 of the recess 3m is located on the outer diameter side of the contact portion 121 of the second contact lip 12d, when the radial position of the outer side opening 2b located at one axial end of the outer ring 2 relative to the hub wheel 3 shifts relatively toward the outer diameter side when the hub wheel 3 is rotating, it is possible to prevent the contact portion 121 of the second contact lip 12d from falling off into the recess 3m and causing a decrease in sealing performance.

[0044] In particular, by configuring the inner diameter side edge 312 of the recess 3m to be positioned 1 mm or more toward the outer diameter side of the contact portion 121 of the second contact lip 12d, it is possible to prevent the contact portion 121 from falling off into the recess 3m and causing a decrease in sealing performance, even if the radial positional deviation of the outer side opening 2b relative to the hub wheel 3 is large.

[0045] Furthermore, the inner diameter side edge 312 of the recess 3m is located on the outer diameter side of the contact portion of the first contact lip 12c with the seal land portion 3d, which is located on the inner diameter side of the second contact lip 12d.Even if the radial position of the outer side opening 2b of the outer ring 2 with respect to the hub wheel 3 shifts relatively toward the outer diameter side, it is possible to prevent the contact portion of the first contact lip 12c with the seal land portion 3d from falling off into the recess 3m, thereby preventing a decrease in sealing performance.

[0046] The recess 3m has a tapered surface 314 that extends from the outer diameter side edge 311 toward the bottom 313 in the radial direction and is inclined toward the outer side from the outer diameter side edge 311 toward the bottom 313. As shown in Fig. 4, the tapered surface 314 is a tapered surface whose inclination angle θ toward the outer side with respect to the radial direction is an acute angle. In this embodiment, the inclination angle θ is set to be 26.5° or less.

[0047] When turning the wheel mounting flange 3b from the flange surface 3k located on the outer diameter side of the recess 3m toward the inner diameter side, the turning tool moves along the movement trajectory shown in Fig. 4. In this case, since the recess 3m has the tapered surface 314, the turning tool can smoothly enter the recess 3m from the flange surface 3k along the tapered surface 314, making it easier for the turning tool to enter the recess 3m. As a result, after turning the flange surface 3k, it is possible to continuously turn the recess 3m without changing the turning tool, and the turning operation of the hub wheel 3 can be simplified.

[0048] In particular, since the inclination angle θ of the tapered surface 314 toward the outer side in the radial direction is a small angle of 26.5° or less, it becomes easy for the turning tool to enter from the flange surface 3k into the recess 3m, making the turning processing operation of the hub wheel 3 even easier.

[0049] As shown in FIG. 5, an inner diameter side edge 312 of the recess 3m protrudes by a dimension D toward the inner side, which is the outer seal member 10 side, beyond an outer diameter side edge 311 in the axial direction.

[0050] When grinding the seal land portion 3d and the inner raceway groove 3c of the hub wheel 3, a grinding wheel 15 having a seal land grinding portion 15a and an inner raceway groove grinding portion 15b is used to simultaneously grind the seal land portion 3d and the inner raceway groove 3c.

[0051] In this case, if the outer diameter side edge 311 of the recess 3m protrudes further toward the inner side than the inner diameter side edge 312, when the seal land portion 3d and the inner raceway groove ground portion 15b are ground with the grinding wheel 15, the grinding wheel 15 may come into contact with the outer diameter side edge 311 of the recess 3m, which may impair processability. Furthermore, when the grinding wheel 15 comes into contact with the outer diameter side edge 311 of the recess 3m, the outer diameter side edge 311 is ground by the grinding wheel 15, which may reduce the processing accuracy of the seal land portion 3d and the inner raceway groove ground portion 15b and shorten the life of the grinding wheel 15.

[0052] However, by forming the inner diameter side edge 312 of the recess 3m to protrude further inward than the outer diameter side edge 311, the grinding wheel 15 does not come into contact with the outer diameter side edge 311 of the recess 3m when grinding the seal land portion 3d and the inner raceway groove ground portion 15b, and the workability of the grinding work is not impaired. Also, because the outer diameter side edge 311 of the recess 3m is not ground by the grinding wheel 15, it is possible to suppress a decrease in the life of the grinding wheel 15 and the processing accuracy of the grinding work.

[0053] 6, the hub ring 3 has a heat-treated portion 31 which has been hardened at least in the range where the inner raceway groove 3c, the seal land 3d, and the recess 3m are formed. In this embodiment, the entire portion where the inner raceway groove 3c and the seal land 3d are formed is hardened, and only a portion where the recess 3m is formed is hardened.

[0054] However, the entire portion where the recess 3m is formed may also be hardened. Also, the inner raceway groove 3c, the seal land portion 3d, and a range beyond the portion where the recess 3m is formed may be hardened.

[0055] The heat-treated portion 31 improves the surface hardness and strength of the hub wheel 3. The hardening in the heat-treated portion 31 can be performed by induction hardening, carburizing hardening or the like.

[0056] The heat-treated portion 31 has an outer peripheral edge 31a which is a boundary with the non-heat-treated portion on the outer surface of the hub wheel 3, and the outer peripheral edge 31a on the outer diameter side of the heat-treated portion 31 is located on the outer diameter side of the bottom 313 of the recess 3m. In this case, the outer peripheral edge 31a of the heat-treated portion 31 is preferably located 1 mm or more on the outer diameter side of the bottom 313 of the recess 3m. In other words, in the radial direction, the separation distance L2 between the bottom 313 of the recess 3m and the outer peripheral edge 31a located on the outer diameter side of the bottom 313 is preferably 1 mm or more.

[0057] When the hub wheel 3 rotates and centrifugal force acts on the wheel mounting flange 3b, the largest stress is applied to the bottom 313 of the recess 3m. Meanwhile, tensile stress is applied to the outer peripheral edge 31a, which is the boundary between the heat-treated portion 31 and the non-heat-treated portion. Therefore, when the outer peripheral edge 31a is located at the bottom 313 of the recess 3m, the bottom 313 is subjected to tensile stress generated at the boundary between the heat-treated portion 31 and the non-heat-treated portion in addition to the large stress due to the centrifugal force. As a result, the stress applied to the bottom 313 becomes excessive, which may cause a crack to occur in the recess 3m.

[0058] Therefore, in the hub wheel 3, the outer peripheral edge 31a of the heat treatment portion 31 is arranged on the outer diameter side of the bottom 313 of the recess 3m, so that the outer peripheral edge 31a is not located at the bottom 313. This prevents excessive stress from being applied to the bottom 313 of the recess 3m, and makes it possible to prevent the occurrence of cracks in the hub wheel 3 that originate from the bottom 313 of the recess 3m.

[0059] Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, which are merely illustrative, and it goes without saying that the present invention can be embodied in various other forms without departing from the gist of the present invention. The scope of the present invention is indicated by the claims, and further includes the equivalent meanings set forth in the claims, and all modifications within the scope of the claims. [Explanation of symbols]

[0060] 1 Wheel bearing device 2 Outer ring 2b Outer side opening 2c (inner side) outer raceway groove 2d (Outer side) Outer raceway groove 3 Hub wheel 3b Wheel mounting flange 3c Inner raceway groove 3d seal land section 3k flange surface 3m recess 4. Inner Circle 4a Inner raceway groove 5 Inner ball row 6 Outer ball row 10 Outer seal member 11 Core wire 12 Sealing material 12c First Contact Lip 12d Second Contact Lip 12e Labyrinth Slip 31 Heat Treatment Section 31a Outer rim 311 Outer diameter edge 312 Inner diameter edge 313 Bottom 314 Tapered surface θ Tilt angle

Claims

1. an outer member having double rows of outer raceway grooves on an inner periphery; an inner member including a hub wheel having a hub flange extending radially outward at one axial end thereof and a small diameter stepped portion extending axially on an outer periphery thereof, and at least one inner ring press-fitted into the small diameter stepped portion of the hub wheel, the inner member having double row inner raceway grooves facing the double row outer raceway grooves; a double row of rolling elements rollably accommodated between the raceway grooves of the outer member and the inner member; a sealing device that closes an open end on one axial end side of an annular space formed by the outer member and the inner member, the hub ring has the inner raceway groove, a seal land portion located at a base end of the hub flange and with which the sealing device slides, a recess portion located on the outer diameter side of the seal land portion in the hub flange, and a flange surface located on the outer diameter side of the recess portion in the hub flange, The sealing device includes a core metal that is fitted to one axial end of the outer member, and a seal member that is integrally joined to the core metal, the seal member has a contact lip that extends from the core metal toward the hub flange and contacts the seal land portion, and a labyrinth slip that extends from the core metal toward the hub flange on an outer diameter side of the contact lip and faces the recess with a gap in the axial direction, The recess is located between an outer diameter side edge and an inner diameter side edge of the recess, and has a bottom where the depth of the recess is greatest, and a tapered surface that extends from the outer diameter side edge toward the bottom in the radial direction and is inclined toward one axial end as it extends from the outer diameter side edge toward the bottom, the hub wheel has a heat-treated portion that is hardened at least within an area in which the inner raceway groove, the seal land portion, and the recessed portion are formed, A wheel bearing device in which an outer peripheral edge of the heat treatment portion is located outer diameter side of the bottom of the recess and inner diameter side of the outer diameter side edge of the recess.

2. The wheel bearing device according to claim 1 , wherein the flange surface and the recess have turned surfaces.

3. 3. The wheel bearing device according to claim 1, wherein an inclination angle of the tapered surface toward the one axial end side with respect to a radial direction is 26.5° or less.

4. the inner raceway groove and the seal land have ground surfaces, 4. The wheel bearing device according to claim 1, wherein the inner diameter side edge of the recess in the hub flange protrudes axially further towards the sealing device than the outer diameter side edge.

5. A wheel bearing device as claimed in any one of claims 1 to 4, wherein the inner diameter side edge portion of the recess in the hub flange is located on the outer diameter side of the contact portion of the contact lip of the seal member with the hub flange.

6. 6. The wheel bearing device according to claim 1, wherein the seal member has one or more of the contact lips.

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