Bearing device for wheel

Abstract

To provide a bearing device for a wheel capable of making the base end part of a wheel mounting flange of a hub wheel have rigidity corresponding to bending moment when a vehicle turns, and reducing damage of a seal lip of a sealing device by foreign matter.SOLUTION: In the bearing device 1 for a wheel, the sealing device includes a seal 30 protruding to an outer diameter side from one axial end portion of the outer ring 2, and a slinger 20 protruding to the outer diameter side from the one axial end portion of the outer ring 2. The fitting position of the slinger 20 to the hub ring 3 is positioned on the outer diameter side of the center of a ball 7 contacting with an inner raceway groove 3c of the hub ring 3, a labyrinth part 40 opening toward the one side in the axial direction is formed by opposing a seal 30 and the slinger 20 with a clearance on the outer diameter side of one side end part in the axial direction of the outer ring 2, a space S positioned outside the sealing device is provided on the inner diameter side of the labyrinth part 40, and a seal member 32 has a seal lip 34 contacting with the slinger 20.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] In recent years, fuel regulations have been imposed on vehicles that use wheel bearing devices in response to social trends such as energy conservation and decarbonization, and the trend toward electrification is progressing. Electric vehicles, which are primarily powered by on-board batteries and are expected to become more popular in the future, tend to be heavier than gasoline-powered vehicles, and their axle loads tend to increase.

[0003] Generally, as the axle load increases, the rotational torque of the wheel bearing device increases, and from the perspective of strength, the wheel bearing device needs to be larger in size. For example, in wheel bearing devices used in electric vehicles, the axial distance from the outer side surface of the wheel mounting flange of the hub wheel to the inner end of the inner ring is smaller than the outer diameter of the inner end of the outer ring, and they tend to be narrow and large in diameter. Furthermore, the mounting dimensions of wheel bearing devices often remain largely unchanged from the past, and the steel ball array is configured to move closer in both the radial and axial directions to the hub bolts that fasten the hub wheel to the wheel or brake components at the wheel mounting flange of the hub wheel. Potential solutions to this problem include thinning the base end of the wheel mounting flange of the hub wheel or reducing the dimensions of each component.

[0004] The wheel mounting flange of the hub wheel supports the wheel that constitutes the wheel. Therefore, when the vehicle turns, a bending moment acts, and a relatively large load is placed on the base end of the wheel mounting flange of the hub wheel. However, if the base end of the wheel mounting flange of the hub wheel is made thin, it may not be possible to ensure rigidity that can withstand the bending moment when the vehicle turns.

[0005] Patent Document 1 describes a wheel-supporting rolling bearing unit including an outer ring having a double-row outer ring raceway on its inner peripheral surface and supported and fixed to a suspension system in use, a hub having a rotating flange for supporting and fixing the wheel near the axial outer end of the outer peripheral surface, and inner ring raceways in the axial middle and inner end portions, a plurality of rolling elements provided for free movement between the inner ring raceway and the outer ring raceway, and a sealing device for closing openings on the axial outer end side of the spaces where the rolling elements are installed, the sealing device being located radially outward from the outer peripheral surface of the axial outer end of the outer ring. This configuration eliminates the need to provide space for a sealing device between the base end of the wheel mounting flange of the hub wheel and the axial outer end of the outer ring, allowing the base end of the wheel mounting flange of the hub wheel to be relatively thick to improve rigidity for withstanding bending moments during vehicle cornering. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent No. 4466112 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the technology described in Patent Document 1, the seal lip of the sealing device is configured to be exposed by contacting the inner circumferential surface near the axially inner end of the slinger. In a configuration in which the seal lip of the sealing device is exposed in this manner, foreign matter such as muddy water is likely to adhere to the seal lip, and the seal lip is likely to be damaged by wear caused by the foreign matter.

[0008] Therefore, the present invention aims to provide a wheel bearing device that can provide the base end of the wheel mounting flange of the hub wheel with rigidity that can withstand the bending moment when the vehicle turns, and that can reduce damage to the seal lip of the sealing device by foreign matter. [Means for solving the problem]

[0009] That is, an outer member having double rows of outer raceway grooves on its inner periphery; an inner member including a hub ring having a wheel mounting flange at one axial end thereof for mounting a wheel, and an inner ring, the inner member having double rows of inner raceway grooves facing the double rows of outer raceway grooves; double-row 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 side of an annular space formed by the outer member and the inner member, The sealing device is a seal including a core metal fitted to the outer periphery of the outer member and a seal member joined to the core metal, the seal protruding radially outward beyond one axial end of the outer member; a slinger fitted to a base end portion of the wheel mounting flange on the other axial side of the hub wheel and protruding radially outward beyond the one axial end portion of the outer member, a fitting position of the slinger relative to the hub wheel is located on the outer diameter side of the center of the rolling element that contacts the inner raceway groove of the hub wheel, The seal and the slinger face each other with a gap between them on the outer diameter side of the one axial end of the outer member, thereby forming a labyrinth portion that extends along the axial direction and opens toward the one axial side, a space located outside the sealing device on the inner diameter side of the labyrinth portion; The seal member protrudes from the core metal toward the slinger and has a seal lip that comes into contact with the slinger. [Effects of the Invention]

[0010] The present invention has the following effects. In other words, according to the present invention, it is possible to improve the rigidity at the base end of the wheel mounting flange of the hub wheel in response to the bending moment when the vehicle turns, and to reduce damage to the seal lip of the sealing device. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a cross-sectional view showing a wheel bearing device according to an embodiment of the present invention; [Figure 2] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 3] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 4] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 5] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 6] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 7] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 8] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 9] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 10] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. [Figure 11] 10 is an enlarged cross-sectional view showing the outer end of the outer ring of the wheel bearing device and the base end of the wheel mounting flange of the hub wheel. FIG. DETAILED DESCRIPTION OF THE INVENTION

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

[0013] [Overall configuration of wheel bearing device] First, a description will be given of a wheel bearing device 1 shown in Figures 1 to 5. The wheel bearing device 1 shown in Figure 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] As shown in Figures 1 and 2, the wheel bearing device 1 has a configuration known as a 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 of inner ball rows 5 and outer ball rows 6, an inner seal member 10, and an outer seal member 9.

[0015] Here, the inner side refers to the vehicle body side of the wheel bearing device 1 when it is attached to the vehicle body, and the outer side refers to the wheel side of the wheel bearing device 1 when it is attached to the vehicle body. The axial direction refers to the direction along the rotation axis X of the wheel bearing device 1, with one axial side being the outer side and the other axial side being the inner side. The direction perpendicular to the rotation axis of the wheel bearing device 1 is referred to as the radial direction. In the following description, the term "cross section" will be used to refer to a cross section that passes through the rotation axis of the wheel bearing device 1 and is parallel to the rotation axis of the wheel bearing device 1.

[0016] An inner-side outer raceway groove 2c and an outer-side outer raceway groove 2d are formed on the inner peripheral surface of the outer ring 2. 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 2f into which fastening members (here, bolts) are inserted to fasten the vehicle body member and the outer ring 2. An outer-side end face 2g of the outer ring 2 is formed as a flat surface parallel to the radial direction.

[0017] The inner end of the outer peripheral surface of the hub wheel 3 is formed with a small-diameter step 3a that is smaller in diameter than the outer end and extends axially on the outer periphery. 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 3d are formed in the wheel mounting flange 3b. Wheel bolts are threaded into the bolt holes 3d from the wheel side to fasten the hub wheel 3 to the wheel or brake component. The structure for fastening the hub wheel 3 to the wheel or brake component may also be fixed by press-fitting a hub bolt and using a nut.

[0018] An outer-side inner raceway groove 3c is provided on the outer peripheral surface of the hub ring 3 so as to face the outer-side outer raceway groove 2d of the outer ring 2. In other words, the inner raceway groove 3c is defined by the hub ring 3 on the outer side of the inner member. An outer-side opening 2b, which is an annular space, is formed between the outer ring 2 and the hub ring 3. An outer-side seal member 9 is fitted into the outer-side end of the outer ring 2 and prevents foreign matter such as muddy water from entering through the outer-side opening 2b. The outer-side seal member 9 is an example of a sealing device.

[0019] The inner ring 4 is mounted on the small-diameter stepped portion 3a of the hub ring 3. The inner ring 4 is press-fitted into the small-diameter stepped portion 3a via a predetermined interference. Furthermore, the inner end of the small-diameter stepped portion 3a of the hub ring 3 is crimped to plastically deform the crimped portion, which unites the hub ring 3 and the inner ring 4 and prevents the inner ring 4 from slipping out of the hub ring 3 in the axial direction. The inner ring 4 applies preload to the inner ball row 5 and outer ball row 6, which are the rolling rows. The outer peripheral surface of the inner ring 4 is provided with an inner-side inner raceway groove 4a, which faces the inner-side outer raceway groove 2c of the outer ring 2. In other words, the inner ring 4 defines the inner raceway groove 4a on the inner side of the inner member. An inner-side opening 2a, which is an annular space, is formed between the outer ring 2 and the inner ring 4. An inner-side seal member 10 is fitted into the inner-side opening 2a to prevent foreign matter, such as muddy water, from entering through the inner-side opening 2a. The inner seal member 10 is an example of a sealing device.

[0020] 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, held in a cage 8. Center P1 indicates the center of a ball 7 constituting the inner ball row 5. Center P2 indicates the center of a ball 7 constituting the outer ball row 6. The inner ball row 5 is rollably sandwiched between the inner raceway groove 4a of the inner ring 4 and the inner-side outer raceway groove 2c 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. In the wheel bearing device 1, the outer ring 2, the hub ring 3 and the inner ring 4, the inner ball row 5, and the outer ball row 6 form a double-row angular contact ball bearing.

[0021] [Base end of hub] The base end 3e on the inner side of the wheel mounting flange 3b of the hub wheel 3 is located on the outer diameter side and outer side of the inner raceway groove 3c. The base end 3e is configured in an annular shape and is connected to the inner raceway groove 3c. When viewed axially and radially, the base end 3e overlaps with the outer end face 2g of the outer ring 2. The base end 3e has an axial surface 3f that is a straight surface parallel to the axial direction, an arc-shaped surface 3g that is convex toward the inner diameter side, and a radial surface 3h that is a straight surface parallel to the radial direction. The axial surface 3f is located on the inner diameter side of the groove bottom of the outer raceway groove 2d of the outer ring 2. The axial surface 3f is configured as a fitted portion into which the fitting portion 21 of the slinger 20 fits. The inner end of the axial surface 3f is connected to the outer end of the inner raceway groove 3c. The inner end of the arc-shaped surface 3g is connected to the outer end of the axial surface 3f. The inner diameter side end of the radial surface 3h is connected to the outer diameter side of the arc-shaped surface 3g.

[0022] The wheel mounting flange 3b of the hub wheel 3 has a flange side surface 3i facing the inner side. The flange side surface 3i is composed of a flat surface parallel to the radial direction. The portion of the flange side surface 3i near the bolt hole 3d is configured as a bearing surface when the wheel bolt is fastened. The flange side surface 3i is located on the outer diameter side and outer side of the base end portion 3e.

[0023] A step portion 3j is formed between the flange side surface 3i and the base end portion 3e of the hub wheel 3. The step portion 3j is configured in an annular shape and connects the flange side surface 3i and the base end portion 3e. The step portion 3j is formed in an arc shape that bends inward as it approaches the inner diameter side and becomes convex toward the inner diameter side. The inner diameter side end of the step portion 3j is connected to the outer diameter side end of the radial surface 3h of the base end portion 3e. The outer diameter side end of the step portion 3j is connected to the inner diameter side end of the flange side surface 3i.

[0024] A predetermined gap is formed between the axial surface 3f of the base end 3e of the hub ring 3 and the outer end face 2g of the outer ring 2. The axial surface 3f of the base end 3e of the hub ring 3 is located radially inward of the groove bottom of the outer raceway groove 2d on the outer side. A radial surface 3h of the base end 3e of the hub ring 3 and the outer end face 2g of the outer ring 2 oppose each other in the axial direction. A predetermined gap is formed between the radial surface 3h of the base end 3e of the hub ring 3 and the outer end face 2g of the outer ring 2.

[0025] [Specific configuration of outer seal member] The outer seal member 9 includes a slinger 20 and a seal 30 .

[0026] The slinger 20 is configured in a substantially annular shape and is fitted onto the outside of the hub wheel 3. The slinger 20 includes a fitting portion 21, an upright portion 22, and an outer diameter portion 23, and is configured to have a substantially S-shaped cross section. The fitting portion 21, the upright portion 22, and the outer diameter portion 23 are formed from metal members made of, for example, steel material.

[0027] The fitting portion 21 of the slinger 20 is cylindrical and fits onto the base end 3e (axial surface 3f) of the hub wheel 3. The fitting portion 21 is formed parallel to the axial direction. The fitting portion 21 is located radially outer than the centers P2 of the balls 7 that make up the outer ball row 6, and radially inner than the groove bottom of the outer raceway groove 2d of the outer ring 2. In other words, the fitting position of the slinger 20 with respect to the hub wheel 3 is located radially outer than the centers P2 of the balls 7 that make up the outer ball row 6, and radially inner than the groove bottom of the outer raceway groove 2d of the outer ring 2.

[0028] The upright portion 22 of the slinger 20 is formed in a substantially annular shape and is located radially outward of the fitting portion 21. The upright portion 22 has a first upright portion 22a, a second upright portion 22b, and a third upright portion 22c. The first upright portion 22a extends radially outward from the fitting portion 21 and is bent at a radially intermediate portion. The first upright portion 22a has a portion extending radially outward and toward the outer side from the fitting portion 21, and a portion extending radially outward from the outer end portion. The inner end of the first upright portion 22a is connected to the outer end of the fitting portion 21. The outer side surface of the portion extending radially outward of the first upright portion 22a contacts the radial surface 3h of the base end 3e of the hub wheel 3. The second upright portion 22b extends radially inward from the first upright portion 22a and is formed parallel to the axial direction. The outer end of the second standing portion 22b is connected to the outer diameter end of the first standing portion 22a. The third standing portion 22c extends radially outward from the second standing portion 22b and is configured parallel to the radial direction. The inner diameter end of the third standing portion 22c is connected to the inner end of the second standing portion 22b.

[0029] The outer diameter portion 23 of the slinger 20 is located on the outer diameter side of the fitting portion 21 and the standing portion 22. The outer diameter portion 23 extends from the third standing portion 22c to the outer side and is configured parallel to the axial direction. The inner side end of the outer diameter portion 23 is connected to the outer diameter side end of the third standing portion 22c.

[0030] The second upright portion 22b, the third upright portion 22c, and the outer diameter portion 23 of the slinger 20 are located radially outward of the radial surface 3h of the base end portion 3e of the hub wheel 3 and the outer end surface 2g of the outer ring 2. In this way, the slinger 20 is configured to protrude radially outward of the outer end of the outer ring 2. The section formed by the second upright portion 22b, the third upright portion 22c, and the outer diameter portion 23 has a generally U-shaped cross section. The area surrounded by the second upright portion 22b, the third upright portion 22c, and the outer diameter portion 23 constitutes a space S. The space S is defined by a portion of the outer surface of the slinger 20 and is located outside the outer seal member 9.

[0031] The seal 30 is configured in a substantially circular ring shape and is fitted onto the outer ring 2. The seal 30 includes a core metal 31 and a seal member 32.

[0032] The core metal 31 of the seal 30 is disposed so as to form a predetermined gap between it and the slinger 20, and is configured so that the core metal 31 and the slinger 20 do not come into contact with each other. The core metal 31 is configured in a substantially annular shape and includes an outer fitting portion 31a, a standing portion 31b, an outer diameter portion 31c, and an end surface abutting portion 31d. The outer fitting portion 31a, the standing portion 31b, the outer diameter portion 31c, and the end surface abutting portion 31d are formed of metal members made of, for example, a steel material.

[0033] The outer fitting portion 31a of the core 31 is cylindrical and is fitted onto the outer periphery of the outer end portion of the outer ring 2. The outer fitting portion 31a is formed parallel to the axial direction. In other words, the fitting position of the core 31 with respect to the outer ring 2 is located on the outer diameter side of the center P2 of the balls 7 that make up the outer ball row 6.

[0034] The standing portion 31b of the core metal 31 is formed in a substantially annular shape and is located on the outer diameter side of the outer fitting portion 31a. The standing portion 31b extends outer diameter side from the outer fitting portion 31a and is formed parallel to the radial direction. The inner diameter side end of the standing portion 31b is connected to the inner side end of the outer fitting portion 31a.

[0035] The outer diameter portion 31c of the core 31 is cylindrical and is located on the outer diameter side of the outer fitting portion 31a and the standing portion 31b. The outer diameter portion 31c extends from the standing portion 31b toward the outer side and is configured parallel to the axial direction. The inner end of the outer diameter portion 31c is connected to the outer diameter end of the standing portion 31b.

[0036] The end face abutment portion 31d of the core metal 31 is configured in a substantially annular shape and is located radially inward relative to the outer fitting portion 31a. The end face abutment portion 31d extends radially inward from the outer fitting portion 31a and is configured parallel to the radial direction. The outer diameter side end of the end face abutment portion 31d is connected to the outer side end of the outer fitting portion 31a. The inner side surface of the end face abutment portion 31d contacts the outer side end face 2g of the outer ring 2. The end face abutment portion 31d is positioned so as to cover substantially the entire outer side end face 2g of the outer ring 2.

[0037] The upright portion 31b and outer diameter portion 31c of the core metal 31 are located on the outer diameter side of the radial surface 3h of the base end portion 3e of the hub wheel 3 and the outer end face 2g of the outer ring 2. In this way, the core metal 31 is configured to protrude outer diameter side beyond the outer end portion of the outer ring 2.

[0038] The slinger 20 and the core 31 of the seal 30 face each other with a gap between them, thereby forming a labyrinth portion 40. The portion of the first upright portion 22a of the slinger 20 extending outwardly faces the end face abutting portion 31d of the core 31, with a gap between them. The second upright portion 22b of the slinger 20 faces the outer fitting portion 31a of the core 31, with a gap between them. The third upright portion 22c of the slinger 20 faces the upright portion 31b of the core 31, with a gap between them. The outer diameter portion 23 of the slinger 20 faces the outer diameter portion 31c of the core 31, with a gap between them. The gap between the outer diameter portion 23 of the slinger 20 and the outer diameter portion 31c of the core 31 constitutes the labyrinth portion 40. The labyrinth portion 40 is configured to open to the outer side by the outer end portions of the outer diameter portion 23 of the slinger 20 and the outer diameter portion 31c of the core metal 31. The labyrinth portion 40 is located on the outer diameter side of the space S and overlaps with the space S when viewed from the radial direction. The opening width (radial width) of the labyrinth portion 40 is configured to be smaller than the radial width of the space S.

[0039] The seal member 32 of the seal 30 is made of, for example, synthetic rubber and is configured to be elastically deformable. The seal member 32 is joined to the core metal 31 by vulcanization bonding or the like. The seal member 32 has a base 33 and two seal lips 34.

[0040] The base 33 of the seal member 32 of the seal 30 is arranged to cover the inner side surface of the standing portion 31b of the core wire 31, the outer diameter side surface of the outer diameter portion 31c, the outer end face of the outer diameter portion 31c, the inner diameter side surface of the outer diameter portion 31c, the outer side surface of the standing portion 31b, and a portion of the outer diameter side surface of the outer fitting portion 31a.

[0041] The base 33 of the sealing member 32 is configured as a part of the core 31. That is, the portion of the base 33 covering the inner side surface of the standing plate portion 31b of the core 31 indicates the inner side surface of the standing plate portion 31b of the core 31. Furthermore, the portion of the base 33 covering the outer side surface of the outer diameter portion 31c of the core 31 indicates the outer side surface of the outer diameter portion 31c of the core 31. The portion of the base 33 covering the inner side surface of the outer diameter portion 31c of the core 31 indicates the inner side surface of the outer diameter portion 31c of the core 31. The portion of the base 33 covering the outer end surface of the outer diameter portion 31c of the core 31 indicates the outer end surface of the outer diameter portion 31c of the core 31. The portion of the base 33 covering the outer side surface of the standing plate portion 31b of the core 31 indicates the outer side surface of the standing plate portion 31b of the core 31. The portion of the base 33 that covers the outer diameter side surface of the outer fitting portion 31a of the core 31 and the portion of the outer diameter side surface of the outer fitting portion 31a of the core 31 that is not covered by the base 33 represent the outer diameter side surface of the outer fitting portion 31a of the core 31.

[0042] The seal lip 34 of the seal member 32 contacts the upright portion 22 of the slinger 20 to prevent foreign matter such as muddy water from entering between the slinger 20 and the core 31. The seal lip 34 is disposed within the space surrounded by the slinger 20 and the core 31 of the seal 30, and is configured so as not to be exposed to the outside. The seal lip 34 is disposed on the inner diameter side of the labyrinth portion 40. The seal lip 34 is provided in a portion of the base 33 that covers the outer side surface of the upright portion 31b, and extends toward the outer diameter side. The seal lip 34 protrudes from the base 33 toward the third upright portion 22c of the slinger 20, and contacts the inner side surface of the third upright portion 22c of the slinger 20. The two seal lips 34 are disposed side by side in the radial direction.

[0043] As described above, the slinger 20 protrudes radially outward beyond the outer end of the outer ring 2, and the core metal 31 protrudes radially outward beyond the outer end of the outer ring 2. As a result, there is no need to ensure space for arranging the outer seal member 9 between the base end 3e of the hub ring 3 and the outer end face 2g of the outer ring 2, and the base end 3e of the hub ring 3 can be made relatively thick, allowing for rigidity that can withstand the bending moment when the vehicle turns.

[0044] As described above, the fitting position of the slinger 20 with respect to the hub wheel 3 is located radially outer than the center P2 of the balls 7 that make up the outer ball row 6, and radially inner than the groove bottom of the outer raceway groove 2d of the outer ring 2. This allows the base end 3e of the hub wheel 3 to be configured with a relatively large thickness, providing rigidity that can withstand the bending moment that occurs when the vehicle turns.

[0045] As described above, the base end 3e of the hub wheel 3 overlaps with the outer end face 2g of the outer ring 2 when viewed in the axial and radial directions. This allows the base end 3e of the hub wheel 3 to be made relatively thick, providing rigidity that can withstand the bending moment when the vehicle turns.

[0046] As described above, the labyrinth portion 40 extends axially and opens toward the outer side, due to the outer diameter portion 23 of the slinger 20 and the outer diameter portion 31c of the core 31 opposing each other with a gap between them on the outer diameter side of the outer end of the outer ring 2. The seal lip 34 of the seal 30 protrudes from the base portion 33 toward the third upright portion 22c of the slinger 20 and contacts the inner side surface of the third upright portion 22c of the slinger 20. Therefore, the labyrinth 40 can prevent foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located. This reduces damage to the seal lip 34 of the seal 30 caused by foreign matter such as muddy water.

[0047] As described above, the space S is located on the inner diameter side of the labyrinth portion 40 and outside the outer seal member 9. This prevents foreign matter such as muddy water from entering the space S and infiltrating into the labyrinth portion 40. This reduces damage to the seal lip 34 of the seal 30 caused by foreign matter such as muddy water.

[0048] As shown in FIG. 3, the core metal 31 of the seal 30 can also be configured with a crank-shaped cross section. The outer fitting portion 31a of the core metal 31 is configured parallel to the axial direction. The standing portion 31b extends radially outward from the outer fitting portion 31a and is configured parallel to the radial direction. The inner diameter side end of the standing portion 31b is connected to the outer side end of the outer fitting portion 31a. The outer diameter portion 31c extends radially outward from the standing portion 31b and is configured parallel to the axial direction. The inner side end of the outer diameter portion 31c is connected to the outer diameter side end of the standing portion 31b.

[0049] In this case, the base 33 of the seal member 32 of the seal 30 is arranged to cover the outer diameter side surface of the outer fitting portion 31a of the core bar 31, the inner side surface of the standing plate portion 31b, the outer diameter side surface of the outer diameter portion 31c, the outer side end face of the outer diameter portion 31c, the inner diameter side surface of the outer diameter portion 31c, and the outer side surface of the standing plate portion 31b.

[0050] As shown in Fig. 4, the slinger 20 of the outer seal member 9 may be configured to include an elastic member 24. The elastic member 24 is made of, for example, synthetic rubber and is configured to be elastically deformable. The elastic member 24 is joined to the upright portion 22 and the outer diameter portion 23 by vulcanization bonding or the like. The elastic member 24 has a base portion 25 and a slinger-side protrusion 26.

[0051] The base 25 of the elastic member 24 of the slinger 20 is arranged to cover a portion of the inner side surface of the third upright portion 22c, the outer diameter side surface of the outer diameter portion 23, the outer end face of the outer diameter portion 23, the inner diameter side surface of the outer diameter portion 23, the outer side surface of the third upright portion 22c, the outer diameter side surface of the second upright portion 22b, and a portion of the outer side surface of the first upright portion 22a.

[0052] The base 25 of the elastic member 24 is configured as a part of the standing plate portion 22 and the outer diameter portion 23. That is, the part of the base 25 that covers the inner side surface of the third standing plate portion 22c and the part of the inner side surface of the third standing plate portion 22c that is not covered by the base 25 refer to the inner side surface of the third standing plate portion 22c. The part of the base 25 that covers the outer diameter side surface of the outer diameter portion 23 refers to the outer diameter side surface of the outer diameter portion 23. The part of the base 25 that covers the outer end surface of the outer diameter portion 23 refers to the outer end surface of the outer diameter portion 23. The part of the base 25 that covers the inner diameter side surface of the outer diameter portion 23 refers to the inner diameter side surface of the outer diameter portion 23. The part of the base 25 that covers the outer side surface of the third standing plate portion 22c refers to the outer side surface of the third standing plate portion 22c. The part of the base 25 that covers the outer diameter side surface of the second standing plate portion 22b refers to the outer diameter side surface of the second standing plate portion 22b. Furthermore, the portion of the base 25 that covers part of the outer side surface of the first standing plate portion 22a and the portion of the base 25 that is not covered on the outer side surface of the first standing plate portion 22a refer to part of the outer side surface of the first standing plate portion 22a.

[0053] The slinger side protrusion 26 of the elastic member 24 of the slinger 20 prevents foreign matter such as muddy water from entering between the slinger 20 and the core 31. The slinger side protrusion 26 is located on the inner diameter side of the outer diameter portion 23 and the labyrinth portion 40. The slinger side protrusion 26 is located on the outer diameter side of the seal lip 34 of the seal 30. The slinger side protrusion 26 is provided in a portion of the base 25 that covers the inner side surface of the third upright portion 22c, and extends toward the inner side. The slinger side protrusion 26 protrudes toward the upright portion 31b of the core 31 of the seal 30. The slinger side protrusion 26 faces the outer side surface of the upright portion 31b of the core 31 of the seal 30 with a gap between them. The slinger side protrusion 26 is configured not to come into contact with the upright portion 31b of the core 31 of the seal 30.

[0054] As described above, slinger-side projection 26 of elastic member 24 of slinger 20 projects toward upright portion 31b of core 31 of seal 30 on the inner diameter side of labyrinth portion 40, and faces the outer side surface of upright portion 31b of core 31 of seal 30 with a gap between them. Therefore, a labyrinth is formed by slinger-side projection 26 of slinger 20 and upright portion 31b of seal 30, which can prevent foreign matter such as muddy water from entering the portion where seal lip 34 of seal 30 is located.

[0055] In this case, the seal member 32 of the seal 30 has one seal lip 34. By configuring the seal member 32 with a small number of seal lips 34 in this way, it is possible to reduce damage to the seal lip 34 of the seal 30 caused by foreign matter such as muddy water, while also achieving low friction.

[0056] As shown in FIG. 5, the seal member 32 may also be configured with a seal-side protrusion 35. The seal-side protrusion 35 prevents foreign matter, such as muddy water, from entering between the slinger 20 and the core 31. The seal-side protrusion 35 is located radially inward of the outer diameter portion 23 of the slinger 20 and radially inward of the labyrinth portion 40. The seal-side protrusion 35 is located radially outward of the seal lip 34. The seal-side protrusion 35 is provided on a portion of the base 33 that covers the outer side surface of the upright portion 31b of the core 31 and extends toward the outer side. The seal-side protrusion 35 protrudes toward the third upright portion 22c of the slinger 20. The seal-side protrusion 35 faces the inner side surface of the third upright portion 22c of the slinger 20 with a gap therebetween. The seal-side protrusion 35 is configured not to contact the third upright portion 22c of the slinger 20.

[0057] As described above, the seal-side projection 35 of the seal member 32 projects toward the third upright portion 22c of the slinger 20 and faces the inner side surface of the third upright portion 22c of the slinger 20 with a gap between them. Therefore, a labyrinth is formed between the seal-side projection 35 of the seal member 32 and the third upright portion 22c of the slinger 20, which prevents foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located.

[0058] Furthermore, in this case, the seal member 32 of the seal 30 includes one seal lip 34. The seal lip 34 is provided in a portion of the base 33 that covers the outer side surface of the end face abutment portion 31d of the core metal 31. The seal lip 34 protrudes from the end face abutment portion 31d of the core metal 31 toward the first upright portion 22a of the slinger 20. By configuring the seal lip 34 in this manner, it is possible to reduce damage to the seal lip 34 of the seal 30 due to foreign matter such as muddy water, while also achieving low friction.

[0059] Furthermore, at this time, the fitting portion 21, first upright portion 22a, second upright portion 22b, and a portion (inner diameter side portion) of third upright portion 22c of slinger 20 are formed of a metal member made of, for example, steel, while a portion (outer diameter side portion) of third upright portion 22c and outer diameter portion 23 are formed of base portion 25 of elastic member 24. Base portion 25 of slinger 20 is configured to extend outward from the outer diameter side end of third upright portion 22c and from that outer diameter side end to the outer side. Third upright portion 22c is formed by the portion of base 25 extending outward from the outer diameter side end of third upright portion 22c and third upright portion 22c. The portion of base 25 extending to the outer side is configured as outer diameter portion 23. The fitting portion 21 and the upright portion 22 of the slinger 20 may be entirely made of a metal member, and the outer diameter portion 23 may be made of the base portion 25 of the elastic member 24 .

[0060] As described above, fitting portion 21 and standing portion 22 of slinger 20 are formed from metal members, and outer diameter portion 23 is formed from elastic member 24. Therefore, slinger 20 can be formed more easily than if fitting portion 21, standing portion 22, and outer diameter portion 23 of slinger 20 were formed from metal members and slinger 20 were formed with a generally S-shaped cross section.

[0061] Additionally, at this time, the elastic member 24 of the slinger 20 has a slinger side protrusion 26. The slinger side protrusion 26 of the slinger 20 is located at the same radial position as the outer diameter portion 23. It is located radially inward of the labyrinth portion 40 and radially outward of the seal lip 34 and seal side protrusion 35 of the seal 30. The slinger side protrusion 26 is formed by protruding the outer diameter portion 23 toward the upright portion 31b of the core metal 31 of the seal 30 beyond the third upright portion 22c.

[0062] As described above, the slinger 20 includes the elastic member 24 having the slinger-side projection 26, and a labyrinth is formed between the slinger-side projection 26 of the slinger 20 and the upright portion 31b of the seal 30. This prevents foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located.

[0063] Next, a description will be given of the wheel bearing device 1 shown in Figures 6 to 11. Note that in the description of the wheel bearing device 1 shown in Figures 6 to 11, parts that are the same as those in the wheel bearing device 1 shown in Figures 1 to 5 will be omitted as appropriate, and the description will focus on parts that differ from the wheel bearing device 1 shown in Figures 1 to 5.

[0064] [Base end of hub] As shown in Figure 6, the hub wheel 3 has a connecting portion 3k that connects the inner raceway groove 3c and the axial surface 3f (fitted portion) of the base end 3e. The connecting portion 3k is formed by a straight surface that extends from the outer end of the inner raceway groove 3c to the outer and outer diameter side. The inner diameter side end of the connecting portion 3k is connected to the outer end of the inner raceway groove 3c, and the outer diameter side end of the connecting portion 3k is connected to the inner side end of the axial surface 3f of the base end 3e.

[0065] A base end portion 3e on the inner side of the wheel mounting flange 3b of the hub wheel 3 is located on the outer diameter side and outer side of the inner raceway groove 3c and the connecting portion 3k, and an axial surface 3f of the base end portion 3e is located on the outer diameter side of the groove bottom of the outer raceway groove 2d of the outer ring 2. When viewed from the axial direction, the axial surface 3f of the base end portion 3e overlaps with the outer side end face 2g of the outer ring 2. The axial surface 3f is configured as a fitted portion into which the fitting portion 21 of the slinger 20 fits.

[0066] [Specific configuration of outer seal member] The outer seal member 9 includes a slinger 20 and a seal 30 .

[0067] The slinger 20 includes a fitting portion 21, a standing portion 22, and an outer diameter portion 23, and is configured to have a substantially U-shaped cross section.

[0068] The fitting portion 21 of the slinger 20 is cylindrically configured and is fitted to the base end 3e (axial surface 3f) of the hub wheel 3. The fitting portion 21 is configured parallel to the axial direction. The standing portion 22 extends radially outward from the fitting portion 21 and is configured parallel to the axial direction. The inner diameter side end of the standing portion 22 is connected to the inner side end of the fitting portion 21. The outer diameter portion 23 is located on the outer diameter side of the fitting portion 21 and the standing portion 22. The outer diameter portion 23 extends radially outward from the standing portion 22 and is configured parallel to the axial direction. The inner side end of the outer diameter portion 23 is connected to the outer diameter side end of the standing portion 22.

[0069] The portion surrounded by fitting portion 21, upright portion 22, and outer diameter portion 23 of slinger 20 is configured as space S. Space S is configured by a part of the outer surface that configures slinger 20, and is located outside outer seal member 9.

[0070] The seal 30 includes a core metal 31 and a seal member 32 .

[0071] The core metal 31 of the seal 30 includes an outer fitting portion 31a, a standing portion 31b, and an end face abutting portion 31d, and is configured to have a crank-shaped cross section.

[0072] The outer fitting portion 31a of the core 31 is fitted onto the outer periphery of the outer end of the outer ring 2. The standing plate portion 31b extends radially outward from the outer fitting portion 31a and is configured parallel to the radial direction. The inner diameter side end of the standing plate portion 31b is connected to the inner end of the outer fitting portion 31a. The end face abutting portion 31d extends radially inward from the outer fitting portion 31a and is configured parallel to the radial direction. The outer diameter side end of the end face abutting portion 31d is connected to the outer end of the outer fitting portion 31a. The end face abutting portion 31d is positioned so as to cover almost the entire outer end face 2g of the outer ring 2. The fitting position of the slinger 20 with the hub wheel 3 (the fitting portion 21 of the slinger 20 and the axial surface 3f of the base end 3e of the hub wheel 3) is within the radial range where the end face abutting portion 31d of the core 31 (one axial end face of the core 31) is located.

[0073] The seal member 32 of the seal 30 includes a base portion 33 , one seal lip 34 , an enlarged diameter portion 36 , and an outer periphery portion 37 .

[0074] The base 33 of the seal member 32 of the seal 30 is provided so as to cover the inner side surface of the standing plate portion 31b of the core metal 31, the outer diameter side end face of the standing plate portion 31b, the outer side surface of the standing plate portion 31b, the outer diameter side surface of the outer fitting portion 31a, and the outer side end face of the end face abutting portion 31d. The base 33 of the seal member 32 is configured as a part of the core metal 31.

[0075] The expanded diameter portion 36 of the sealing member 32 protrudes radially outward from the outer fitting portion 31a of the core metal 31. The expanded diameter portion 36 is configured in a generally annular shape. The outer diameter side surface of the expanded diameter portion 36 is located radially outward of the outer diameter side surface of the outer diameter portion 23 of the slinger 20. The outer side surface of the expanded diameter portion 36 is continuous with a portion covering the outer end surface of the end face abutting portion 31d of the base portion 33, and generally coincides with the portion covering the outer end surface of the end face abutting portion 31d of the base portion 33 in the axial direction.

[0076] The outer peripheral portion 37 of the seal member 32 extends from the expanded diameter portion 36 to the outer side in the axial direction. The outer side end of the outer peripheral portion 37 roughly coincides with the outer side end of the outer diameter portion 23 of the slinger 20 in the axial direction.

[0077] The upright portion 22 of the slinger 20 faces the end face abutment portion 31d of the core 31 and the expanded diameter portion 36 of the seal member 32 with a gap therebetween. The outer diameter portion 23 of the slinger 20 faces the outer periphery 37 of the seal member 32 with a gap therebetween. The gap between the outer diameter portion 23 of the slinger 20 and the outer periphery 37 of the seal member 32 constitutes a labyrinth portion 40. The outer end portions of the outer diameter portion 23 of the slinger 20 and the outer periphery 37 of the seal member 32 configure the labyrinth portion 40 to open to the outer side. The labyrinth portion 40 is located on the outer diameter side of the space S and overlaps with the space S when viewed radially.

[0078] As described above, the fitting position of the slinger 20 with respect to the hub wheel 3 is within the range in the radial direction where the end face abutment portion 31d (one axial end face of the core bar 31) of the core bar 31 is located. Therefore, the base end portion 3e of the hub wheel 3 can be made relatively thick, and can be made rigid enough to withstand the bending moment when the vehicle turns.

[0079] As described above, the fitting position of the slinger 20 with respect to the hub wheel 3 is within the range in the radial direction where the end face abutment portion 31d (one axial end face of the core bar 31) of the core bar 31 is located. Therefore, the base end portion 3e of the hub wheel 3 can be made relatively thick, and can be made rigid enough to withstand the bending moment when the vehicle turns.

[0080] As described above, the labyrinth portion 40 extends axially and opens toward the outer side, as a result of the outer diameter portion 23 of the slinger 20 and the outer peripheral portion 37 of the core metal 31 opposing each other with a gap between them on the outer diameter side of the outer end of the outer ring 2. The seal lip 34 of the seal 30 protrudes from the base portion 33 toward the upright portion 22 of the slinger 20 and comes into contact with the inner side surface of the upright portion 22 of the slinger 20. Therefore, the labyrinth 40 can prevent foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located. This reduces damage to the seal lip 34 of the seal 30 caused by foreign matter such as muddy water.

[0081] As described above, the space S is located on the inner diameter side of the labyrinth portion 40 and outside the outer seal member 9. This prevents foreign matter such as muddy water from entering the space S and infiltrating into the labyrinth portion 40. This reduces damage to the seal lip 34 of the seal 30 caused by foreign matter such as muddy water.

[0082] As shown in Fig. 7, the slinger 20 of the outer seal member 9 may also be configured to include an elastic member 24. The elastic member 24 is made of, for example, synthetic rubber and is configured to be elastically deformable. The elastic member 24 is joined to the upright portion 22 and the outer diameter portion 23 by vulcanization bonding or the like. The elastic member 24 has a base portion 25 and a slinger-side protrusion 26.

[0083] The base portion 25 of the elastic member 24 of the slinger 20 is provided so as to cover a part of the inner side surface of the standing plate portion 22 and the outer diameter side surface of the outer diameter portion 23. The base portion 25 is configured as a part of the standing plate portion 22 and the outer diameter portion 23.

[0084] The slinger side protrusion 26 of the elastic member 24 of the slinger 20 is positioned radially inward relative to the outer diameter portion 23 and the labyrinth portion 40. The slinger side protrusion 26 is positioned radially outward relative to the seal lip 34 of the seal 30. It is provided on the portion of the base 25 that covers the upright portion 22 and extends toward the inner side. The slinger side protrusion 26 protrudes toward the expanded diameter portion 36 of the seal member 32 of the seal 30. The slinger side protrusion 26 faces the outer side surface of the expanded diameter portion 36 of the seal member 32 with a gap between them.

[0085] As described above, slinger-side projection 26 of elastic member 24 of slinger 20 projects toward upright portion 31b of core 31 of seal 30 on the inner diameter side of labyrinth portion 40, and faces the outer side surface of upright portion 31b of core 31 of seal 30 with a gap between them. Therefore, a labyrinth is formed by slinger-side projection 26 of slinger 20 and upright portion 31b of seal 30, which can prevent foreign matter such as muddy water from entering the portion where seal lip 34 of seal 30 is located.

[0086] As shown in FIG. 8 , the fitting portion 21 and a portion (inner diameter side portion) of the standing portion 22 of the slinger 20 can be formed of a metal member made of, for example, steel, while a portion (outer diameter side portion) of the standing portion 22 and the outer diameter portion 23 can be formed of a base portion 25 of an elastic member 24. In this case, the base portion 25 is configured to extend from the outer diameter side end of the standing portion 22 toward the outer diameter side and from that outer diameter side end toward the outer side. The standing portion 22 is formed by the portion of the base portion 25 extending from the outer diameter side end of the standing portion 22 toward the outer diameter side and the standing portion 22. The portion of the base portion 25 extending toward the outer diameter side is configured as the outer diameter portion 23. The slinger side protrusion 26 is located on the inner diameter side of the outer diameter portion 23. The slinger side protrusion 26 is formed by protruding the outer diameter portion 23 toward the standing portion 31b of the core metal 31 of the seal 30 beyond the standing portion 22. The fitting portion 21 and the upright portion 22 of the slinger 20 may be entirely made of a metal member, and the outer diameter portion 23 may be made of the base portion 25 of the elastic member 24 .

[0087] As described above, fitting portion 21 and standing portion 22 of slinger 20 are formed from metal members, and outer diameter portion 23 is formed from elastic member 24. Therefore, slinger 20 can be formed more easily than if fitting portion 21, standing portion 22, and outer diameter portion 23 of slinger 20 were formed from metal members and slinger 20 were formed with a generally U-shaped cross section.

[0088] 9, the expanded diameter portion 36 of the seal member 32 of the seal 30 may be configured to have a first expanded diameter portion 36a and a second expanded diameter portion 36b. The first expanded diameter portion 36a of the seal member 32 protrudes radially outward from the outer fitting portion 31a of the core 31. The second expanded diameter portion 36b protrudes radially outward from the first expanded diameter portion 36a. The outer side surface of the second expanded diameter portion 36b is located closer to the inner side than the outer side surface of the first expanded diameter portion 36a, and the second expanded diameter portion 36b is recessed further away from the upright portion of the slinger than the first expanded diameter portion 36a.

[0089] In this case, the fitting portion 21 and a portion (inner diameter side portion) of the standing portion 22 of the slinger 20 are formed of a metal member, and a portion (outer diameter side portion) of the standing portion 22 and the outer diameter portion 23 are formed of a base portion 25 of the elastic member 24. The base portion 25 is configured to extend outward from the outer diameter side end of the standing portion 22 and then from that outer diameter side end to the outer side. The portion of the base portion 25 extending outward constitutes the outer diameter portion 23. The slinger side protrusion 26 is formed by protruding the outer diameter portion 23 toward the second expanded diameter portion 36b of the seal member 32 of the seal 30 beyond the standing portion 22. The inner side end of the slinger side protrusion 26 is located more inward than the outer side surface of the first expanded diameter portion 36a of the seal member 32 of the seal 30. The inner side end of the slinger side protrusion 26 faces the outer side surface of the second expanded diameter portion 36b of the seal member 32 of the seal 30 with a gap therebetween. Slinger-side projection 26 and second enlarged diameter portion 36b of seal member 32 in seal 30 are configured so as to be non-contacting. Note that the fitting portion 21 and standing portion 22 of slinger 20 may be entirely formed of a metal member, with outer diameter portion 23 formed of base 25 of elastic member 24. The fitting portion 21, standing portion 22, and outer diameter portion 23 of slinger 20 may also be formed of a metal member, with slinger-side projection 26 provided on a portion of base 25 that covers standing portion 22.

[0090] As described above, the inner end of the slinger-side projection 26 of the slinger 20 faces the outer side surface of the second expanded diameter portion 36b of the seal member 32 of the seal 30 with a gap between them. Therefore, a labyrinth is formed by the slinger-side projection 26 of the slinger 20 and the second expanded diameter portion 36b of the seal 30, which prevents foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located.

[0091] As described above, the second expanded diameter portion 36b of the seal 30 is recessed further away from the upright portion 22 of the slinger 20 than the first expanded diameter portion 36a, and the slinger-side projection 26 of the slinger 20 is formed by projecting the outer diameter portion 23 toward the second expanded diameter portion 36b of the seal member 32 of the seal 30 beyond the upright portion 22. Therefore, the labyrinth formed by the slinger-side projection 26 of the slinger 20 and the second expanded diameter portion 36b of the seal 30 is relatively long, which can prevent foreign matter such as muddy water from entering the portion where the seal lip 34 of the seal 30 is located.

[0092] As shown in Figure 10, the expanded diameter portion 36 of the seal member 32 of the seal 30 has a first expanded diameter portion 36a and a second expanded diameter portion 36b, and further, the upright portion 22 of the slinger 20 can be configured to have a first upright portion 22a and a second upright portion 22b.

[0093] The first upright portion 22a of the slinger 20 extends radially outward from the fitting portion 21. The inner diameter side end of the first upright portion 22a is connected to the inner side end of the fitting portion 21. The second upright portion 22b extends radially outward from the first upright portion 22a and is configured to bend at a radially intermediate portion. The second upright portion 22b has a portion extending radially inward from the first upright portion 22a and a portion extending radially outward from the inner side end. The outer side end of the second upright portion 22b is connected to the outer diameter side end of the first upright portion 22a. In this way, the second upright portion 22b protrudes further toward the expanded diameter portion 36 of the seal member 32 in the seal 30 than the first upright portion 22a.

[0094] At this time, base 25 of slinger 20 covers part of the inner side surface of second upright portion 22b and the outer diameter side surface of outer diameter portion 23. Slinger-side protrusion 26 is provided on the portion of base 25 that covers second upright portion 22b, is positioned on second upright portion 22b, and faces the outer side surface of second expanded diameter portion 36b of seal member 32 of seal 30 with a gap therebetween.

[0095] As described above, the second upright portion 22b of the slinger 20 protrudes further toward the expanded diameter portion 36 of the seal member 32 of the seal 30 than the first upright portion 22a, and the slinger side projection 26 is located on the second upright portion 22b. Therefore, the labyrinth formed by the second upright portion 22b of the slinger 20 and the expanded diameter portion 36 of the seal 30, and the slinger side projection 26 and the second expanded diameter portion 36b of the seal 30, is relatively long, preventing foreign matter such as muddy water from entering the area where the seal lip 34 of the seal 30 is located.

[0096] As shown in Figure 11, the seal member 32 of the seal 30 can also be configured to have an inner diameter side seal lip 38. The inner diameter side seal lip 38 contacts the connection portion 3k of the hub wheel 3 to prevent foreign matter such as muddy water from entering between the connection portion 3k of the hub wheel 3 and the core 31. The inner diameter side seal lip 38 is positioned on the inner diameter side of the seal lip 34. The inner diameter side seal lip 38 is provided in a portion that covers the outer side surface of the end face abutment portion 31d of the base 33, and extends toward the inner diameter side and the outer side. The inner diameter side seal lip 38 protrudes from the base 33 toward the connection portion 3k of the hub wheel 3 and contacts the connection portion 3k of the hub wheel 3.

[0097] As described above, the inner diameter side seal lip 38 of the seal 30 protrudes from the base 33 toward the connecting portion 3k of the hub wheel 3 and comes into contact with the connecting portion 3k of the hub wheel 3. This more reliably prevents foreign matter such as muddy water from entering between the connecting portion 3k of the hub wheel 3 and the core 31. This also makes it possible to prevent grease from leaking from the outer raceway groove 2d of the outer ring 2 and the inner raceway groove 3c of the hub wheel 3 toward the seal ship 34. Note that in the wheel bearing device 1 shown in FIGS. 6 to 11 as well, the seal member 32 of the seal 30 may be configured to have an inner diameter side seal lip 38.

[0098] Although a so-called third-generation wheel bearing device has been exemplified, the wheel bearing device according to the present invention is not limited to this structure and may, for example, have a first- or second-generation structure in which a pair of inner rings are press-fit into a small-diameter stepped portion of a hub ring, or a fourth-generation structure in which inner raceway grooves are formed on the outer peripheral surfaces of the hub ring and constant velocity universal joint to form inner members. Also, while a double-row angular contact ball bearing in which rows of balls are used as rolling elements has been exemplified, the present invention is not limited to this and may also be a double-row tapered roller bearing in which tapered rollers are used as rolling elements.

[0099] Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, which are merely examples, and it goes without saying that the present invention can be embodied in various other forms without departing from the spirit 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]

[0100] 1 Wheel bearing device 2 outer ring 2a Inner side opening 2b Outer side opening 2c Outer raceway groove 2d outer raceway groove 2g Outer end face 3 Hub Wheel 3a Small diameter stepped section 3b Wheel mounting flange 3c Inner raceway groove 3e Proximal end 3f Axial plane 3g Arc-shaped surface 3h Radial surface 3i Flange side 3j Step 3k connection 4. Inner Circle 5 Inner ball row 6 Outer ball row 7 Ball 8 Cage 9 Outer seal member 10 Inner seal member 20 Slinger 21 Fitting part 22 Standing board 23 Outer diameter part 24 Elastic member 25 base 26 Slinger side protrusion 30 stickers 31 Core 31a External fitting part 31b Standing board section 31c Outer diameter part 31d End surface contact part 32 Sealing material 33 Base 34 Sealing lip 35 Seal side protrusion 36 Expanded diameter part 37 Outer periphery 40 Labyrinth Section S space

Claims

1. an outer member having double-row outer raceway grooves on its inner periphery; an inner member including a hub ring having a wheel mounting flange at one axial end thereof for mounting a wheel, and an inner ring, the inner member having double rows of inner raceway grooves facing the double rows of outer raceway grooves; double-row 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 side of an annular space formed by the outer member and the inner member, The sealing device is a seal including a core metal fitted to the outer periphery of the outer member and a seal member joined to the core metal, the seal protruding radially outward beyond one axial end of the outer member; a slinger fitted to a base end portion of the wheel mounting flange on the other axial side of the hub wheel and protruding radially outward beyond the one axial end portion of the outer member, a fitting position of the slinger relative to the hub wheel is located on the outer diameter side of the center of the rolling element that contacts the inner raceway groove of the hub wheel, The seal and the slinger face each other with a gap between them on the outer diameter side of the one axial end of the outer member, thereby forming a labyrinth portion that extends along the axial direction and opens toward the one axial side, a space located outside the sealing device on the inner diameter side of the labyrinth portion; The seal member protrudes from the core metal toward the slinger and has a seal lip that comes into contact with the slinger.

2. 2. The wheel bearing device according to claim 1, wherein the fitting position of the slinger with respect to the hub wheel is located radially inward of a groove bottom of the outer raceway groove of the outer member.

3. 3. The wheel bearing device according to claim 1, wherein the slinger has a slinger-side protrusion that protrudes toward the seal on an inner diameter side of the labyrinth portion and faces the seal with a gap therebetween.

4. the seal lip projects from a portion of the core metal that abuts against the one axial end surface of the outer member toward the slinger, 4. The wheel bearing device according to claim 3, wherein the seal member has a seal-side protrusion that protrudes from the core metal toward the slinger and faces the slinger with a gap therebetween.

5. The fitting position of the slinger with respect to the hub wheel is within a range in the radial direction in which the one axial end face of the core metal is located, the core metal has an outer fitting portion fitted onto the outer periphery of the outer member, and an end surface abutment portion extending from the outer fitting portion toward the inner diameter side and contacting one axial end surface of the outer member, the seal member has an expanded diameter portion that protrudes radially outward from the outer fitting portion of the core metal, and an outer circumferential portion that extends axially from the expanded diameter portion, The slinger has a fitting portion that fits onto the hub wheel, a standing portion that extends from the fitting portion toward the outer diameter side and faces the enlarged diameter portion with a gap, and an outer diameter portion that extends from the standing portion along the axial direction and faces the outer periphery portion with a gap, the labyrinth portion is formed by the outer circumferential portion of the seal member and the outer diameter portion of the slinger, 2. The wheel bearing device according to claim 1, wherein the seal lip projects from the end face abutment portion of the core metal toward the slinger.

6. 6. The wheel bearing device according to claim 5, wherein the slinger has a slinger-side protrusion that protrudes from the upright portion toward the seal and faces the seal with a gap therebetween.

7. The upright portion of the slinger has a first upright portion extending from the fitting portion toward the outer diameter side and a second upright portion extending from the first upright portion toward the outer diameter side, the second upright portion protrudes further toward the enlarged diameter portion of the seal member than the first upright portion, 7. The wheel bearing device according to claim 6, wherein the slinger-side projection is located on the second upright portion.

8. The fitting portion and the upright portion of the slinger are formed of metal members, 7. The wheel bearing device according to claim 6, wherein the outer diameter portion of the slinger is formed of an elastic member joined to the metal member.

9. the enlarged diameter portion of the sealing member has a first enlarged diameter portion that protrudes radially outward from the outer fitting portion of the core metal, and a second enlarged diameter portion that protrudes radially outward from the first enlarged diameter portion, The second enlarged diameter portion is recessed further away from the upright portion of the slinger than the first enlarged diameter portion, The wheel bearing device according to claim 8, wherein the slinger-side projection is formed by projecting the outer diameter portion of the slinger beyond the upright portion toward the second enlarged diameter portion of the seal member.

10. the hub wheel has a fitted portion into which the fitting portion of the slinger fits, and a connecting portion that connects the fitted portion and the inner raceway groove, 6. The wheel bearing device according to claim 5, wherein the seal member has an inner diameter side seal lip that protrudes from the end face abutment portion of the core metal toward the connecting portion and comes into contact with the connecting portion.

Images