JP2022147755A - Wheel bearing device - Google Patents

Abstract

To provide a wheel bearing device which can easily discharge muddy water intruding into a labyrinth seal of a sealing device.SOLUTION: An inner-side seal member 10 of a wheel bearing device 1 comprises: a seal member 13 having a core grid 11 composed of an inner fitting part 11a fit to an outer ring 2, and a side plate part 11b extending to an inside-diameter side from an outer-side end part of the inner first part 11a, and an elastic member 12 integrally joined to the core grid 11; and a slinger 14 having an outer fitting part 14a fit to an inner ring 4, a circular ring part 14b extending to an outside-diameter side from the inner-side end part of the outer fitting part 14a, and opposing the side plate part 11b in an axial direction, and a protrusion 14c protruding toward the side plate part 11b side from the outside-diameter end part of the circular ring part 14b, and opposing the side plate part 11b with a clearance between the side plate part and itself. The inner fitting part 11a and the protrusion 14c are overlapped on each other when viewed from a radial direction, and the seal member 13 has a drain part 13A in which the inner fitting part 11a is notched in the axial direction in a prescribed region at a road face side in a peripheral direction.SELECTED DRAWING: Figure 2

Description

The present invention relates to a wheel bearing device.

2. Description of the Related Art Conventionally, there has been known a wheel bearing device that rotatably supports a wheel in a suspension system of an automobile or the like. A 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.

For example, the sealing device disclosed in Patent Literature 1 includes a core bar including an inner fitting portion fitted to the inner periphery of an outer ring, which is an outer member, and a side plate portion extending radially inward from the inner fitting portion, and a core A seal member having an elastic member integrally joined to gold and having a plurality of seal lips formed thereon, an outer fitting portion fitted to the outer periphery of an inner ring as an inner member, and extending radially outward from the outer fitting portion. A slinger having a disc portion and a protruding portion that protrudes from the disc portion toward the side plate portion and faces the side plate portion with a gap therebetween.

A labyrinth seal is formed by the inner fitting portion of the cored bar, the protruding portion of the slinger, and the seal lip located on the outermost diameter side of the elastic member to improve resistance to muddy water and prevent muddy water from entering the sealing device. is suppressed.

Japanese Patent No. 5170366

However, as in the sealing device described in Patent Document 1, in a configuration in which a labyrinth seal is formed using a protruding portion that protrudes from the disk portion of the slinger toward the side plate portion side, muddy water once enters the labyrinth seal. Once infiltrated, it is difficult to be discharged to the outside, and as a result, an improvement in muddy water resistance performance is hindered.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a wheel bearing device that can easily discharge muddy water that has entered the inside of the labyrinth seal even when the labyrinth seal is formed in the sealing device. It is a thing.

That is, the wheel bearing device includes an outer member having a double-row outer raceway surface on the inner periphery, a hub wheel having a small-diameter stepped portion extending axially on the outer periphery, and a hub wheel press-fitted to the small-diameter stepped portion of the hub wheel. An inner member consisting of at least one inner ring and having a double-row inner raceway surface facing the double-row outer raceway surface, and freely rolling between both raceway surfaces of the outer member and the inner member A wheel bearing device comprising: a double-row rolling element housed therein; The sealing device includes a core bar including an inner fitting portion fitted to the inner circumference of the outer member, and a side plate portion extending radially inwardly from the other axial end of the inner fitting portion, and a seal member having an elastic member that is integrally joined; an outer fitting portion that is fitted to the outer periphery of the inner member; a slinger having an annular portion facing a side plate portion, and a projecting portion projecting from an outer diameter side end portion of the annular portion toward the side plate portion side and facing the side plate portion with a gap; The inner fitting portion of the seal member and the protruding portion of the slinger overlap each other when viewed in the radial direction, and the seal member is configured so that the inner fitting portion cuts in the axial direction in a predetermined region on the road surface side in the circumferential direction. It has a missing drain.

According to the present invention, muddy water that has entered the inside of the sealing device can be easily discharged to the outside of the sealing device through the drain portion, and the muddy water resistance performance of the sealing device can be effectively improved.

It is a side sectional view showing a bearing device for wheels. It is a side sectional view showing an inner side seal member. It is the figure which looked at the part by the side of the road surface of the inner seal member from the inner side in the direction of an axis. FIG. 5 is a side cross-sectional view showing a state in which the inner peripheral surface of the inner side opening of the outer ring largely protrudes below the drain portion of the inner side seal member. It is a side cross-sectional view showing another embodiment of the inner side seal member.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments for carrying out the present invention will be described below with reference to the accompanying drawings.

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

The wheel bearing device 1 has a configuration called a third generation, and includes an outer ring 2 as an outer member, a hub wheel 3 and an inner ring 4 as inner members, and two rows of inner rings as rolling trains. It comprises a side ball row 5, an outer side ball row 6, an inner side seal member 10, and an outer side seal member 20. - 特許庁

Here, the inner side indicates the vehicle body side of the wheel bearing device 1 when attached to the vehicle body, and the outer side indicates the wheel side of the wheel bearing device 1 when attached to the vehicle body. Further, the lower side of the wheel bearing device 1 when attached to the vehicle body is referred to as the road surface side, and the upper side thereof is referred to as the anti-road surface side. Furthermore, the axial direction represents the direction along the rotation axis of the wheel bearing device 1 . In this embodiment, the inner side is the one end side in the axial direction, and the outer side is the other end side in the axial direction.

An inner side opening 2a into which an inner side sealing member 10 can be fitted is formed at the inner side end portion of the outer ring 2 . An outer-side opening 2b into which an outer-side seal member 20 can be fitted is formed at the outer-side end of the outer ring 2 .

By fitting the inner seal member 10 into the inner opening 2a, the inner side of the annular space S formed by the outer ring 2, which is the outer member, and the hub wheel 3 and the inner ring 4, which are the inner members. The open end is blocked. The open end of the annular space S on the outer side is closed by fitting the outer side seal member 20 into the outer side opening 2b.

The inner-side sealing member 10 and the outer-side sealing member 20 are sealing devices that close the open end of the annular space S. As shown in FIG. In this manner, the inner side seal member 10 and the outer side seal member 20 close the open ends of the annular space S on the inner side and the outer side, thereby preventing foreign matter such as muddy water from entering the inside of the wheel bearing device 1 . suppressed.

An inner raceway surface 2c on the inner side and an outer raceway surface 2d on the outer side 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 attachment flange 2 e is provided with bolt holes 2 f into which fastening members (here, bolts) for fastening the vehicle body side member and the outer ring 2 are inserted.

A small-diameter stepped portion 3 a having a diameter smaller than that of the outer end portion is formed at the inner end portion of the outer peripheral surface of the hub wheel 3 . A wheel mounting flange 3b for mounting a wheel is integrally formed on the outer side end of the hub wheel 3. As shown in FIG. A plurality of bolt holes 3f are formed in the wheel mounting flange 3b. A hub bolt for fastening the hub wheel 3 and a wheel or brake component can be press-fitted into the bolt hole 3f.

In the hub wheel 3, a slidable contact surface 3d is formed on the base side of the wheel mounting flange 3b with which the outer side seal member 20 slidably contacts. An outer-side inner raceway surface 3 c is provided on the outer peripheral surface of the hub wheel 3 so as to face the outer-side outer raceway surface 2 d of the outer ring 2 . That is, the inner raceway surface 3c is formed by the hub wheel 3 on the outer side of the inner member.

An inner ring 4 is provided on the small diameter step portion 3 a of the hub wheel 3 . The inner ring 4 is fixed to the small-diameter stepped portion 3a of the hub wheel 3 by press-fitting and caulking. The inner ring 4 applies preload to the inner ball row 5 and the outer ball row 6, which are rolling rows. The inner ring 4 has an inner end face 4b at the inner end. The hub wheel 3 has an inner side end portion formed with a crimped portion 3h which is crimped to the inner side end face 4b of the inner ring 4. As shown in FIG.

An inner raceway surface 4 a is provided on the outer peripheral surface 4 c of the inner ring 4 so as to face the inner raceway surface 2 c of the outer ring 2 . That is, the inner raceway surface 4a is formed by the inner ring 4 on the inner side of the inner member.

The inner ball row 5 and the outer ball row 6, which are rolling rows, are formed by holding a plurality of balls 7, which are rolling elements, by a retainer 8. As shown in FIG. The inner ball row 5 is rotatably sandwiched between the inner raceway surface 4a of the inner ring 4 and the outer raceway surface 2c of the outer ring 2 on the inner side. The outer-side ball row 6 is rollably sandwiched between the inner raceway surface 3c of the hub wheel 3 and the outer-side raceway surface 2d of the outer ring 2 . That is, the inner ball row 5 and the outer ball row 6 are housed so as to roll freely between the raceway surfaces of the outer member and the inner member.

In the wheel bearing device 1, the outer ring 2, the hub ring 3, the inner ring 4, the inner ball train 5, and the outer ball train 6 constitute a double row angular contact ball bearing. Note that the wheel bearing device 1 may constitute a double-row tapered roller bearing instead of the double-row angular contact ball bearing.

[Outer side seal member]
The outer side seal member 20 has a metal core 21 and an elastic member 22 . The core bar 21 is made of, for example, a steel plate and has a cylindrical shape, and is internally fitted to the outer opening 2b of the outer ring 2 .

The elastic member 22 is made of synthetic rubber, for example, and is joined to the core metal 21 by vulcanization adhesion. The elastic member 22 has a base portion 22a vulcanized and bonded to the core metal 21, and a first side lip 22b, a second side lip 22c, and a grease lip 22d extending from the base portion 22a and formed in an annular shape. is doing.

The first side lip 22b is positioned radially closest to the seal lips of the elastic member 22, and extends radially outward from the base portion 22a. The second side lip 22c is located on the inner diameter side of the first side lip 22b, and extends from the base portion 22a toward the outer diameter side and the outer side. The grease lip 22b is located on the inner diameter side of the second side lip 22c and extends from the base portion 22a toward the inner diameter side and the inner side.

The first side lip 22b, the second side lip 22c, and the grease lip 22d of the elastic member 22 are in slidable contact with the lip sliding contact surface 3d of the hub wheel 3. As shown in FIG.

[Inner side seal member]
As shown in FIG. 2( a ), the inner side seal member 10 includes a seal member 13 having a metal core 11 and an elastic member 12 and a slinger 14 . The core metal 11 is made of, for example, a steel plate, and includes a cylindrical inner fitting portion 11a fitted to the inner periphery of the inner side opening 2a of the outer ring 2, and a cylindrical inner fitting portion 11a that extends from the outer side end portion of the inner fitting portion 11a toward the inner diameter side. and an extending annular side plate portion 11b. The inner side opening 2a of the outer ring 2 is an example of a fitted portion into which the inner fitting portion 11a of the core metal 11 is fitted.

The elastic member 12 is made of synthetic rubber, for example, and is integrally joined to the metal core 11 by vulcanization adhesion. The elastic member 12 has a base portion 121 that is vulcanized and bonded to the core metal 11, and a first side lip 122, a second side lip 123, and a grease lip 124 that extend from the base portion 121 and are each formed in an annular shape. is doing. The first side lip 122 , the second side lip 123 and the grease lip 124 are seal lips of the elastic member 12 .

The base portion 121 is joined to the inner peripheral surface, the inner side end surface, and the inner side portion of the outer peripheral surface of the inner fitting portion 11a, and the inner side surface, the inner diameter side end surface, and the inner diameter side portion of the outer side surface of the side plate portion 11b. there is

The first side lip 122 is located on the outermost diameter side among the seal lips of the elastic member 12 and extends from the base portion 121 toward the outer diameter side and the inner side. The first side lip 122 is an example of an outermost seal lip. The second side lip 123 is located on the inner diameter side of the first side lip 122 and extends from the base portion 121 toward the outer diameter side and the inner side. The grease lip 124 is located on the inner diameter side of the second side lip 123 and extends from the base portion 121 toward the inner diameter side and the outer side.

The slinger 14 is made of, for example, a steel plate, and has a cylindrical outer fitting portion 14a fitted to the outer peripheral surface 4c at the inner end portion of the inner ring 4 and an outer diameter side from the inner end portion of the outer fitting portion 14a. and a projecting portion 14c projecting from the outer diameter side end portion of the annular portion 14b toward the outer side, which is the side plate portion 11b side.

The projecting portion 14c is positioned between the inner fitting portion 11a of the core metal 11 and the first side lip 122 of the elastic member 12 in the radial direction. The annular portion 14b of the slinger 14 is located on the inner side of the side plate portion 11b of the cored bar 11 in the axial direction, and the annular portion 14b and the side plate portion 11b face each other in the axial direction. The tip of the projecting portion 14c faces the side plate portion 11b of the cored bar 11 with a gap in the axial direction.

The first side lip 122 of the elastic member 12 faces the annular portion 14b of the slinger 14 with a gap d1 in the axial direction. That is, the first side lip 122 is a non-contact lip provided in a non-contact state with the annular portion 14b. The tip surface 122a of the first side lip 122 faces the outer diameter side in the radial direction, and is located on the inner side by a distance d2 from the outer-side end portion (side plate portion 11b side end portion) of the projecting portion 14c of the slinger 14. (Circular portion 14b side).

The second side lip 123 of the elastic member 12 faces the annular portion 14b of the slinger 14 in the axial direction. The tip of the second side lip 123 is in slidable contact with the annular portion 14b, and the second side lip 123 is a contact lip. The first side lip 122 and the second side lip 123 are seal lips extending toward the annular portion 14b side of the slinger 14 in the axial direction.

The grease lip 124 of the elastic member 12 faces the outer fitting portion 14a of the slinger 14 in the radial direction. The tip of the grease lip 124 is in slidable contact with the outer fitting portion 14a, and the grease lip 124 is a contact lip.

In the inner side seal member 10 configured as described above, the inner fitting portion 11a of the core metal 11 of the seal member 13, the projecting portion 14c of the slinger 14, and the first side lip 122 of the elastic member 12 of the seal member 13 are arranged. are overlapped when viewed from the radial direction, and the inner fitting portion 11a, the projecting portion 14c, and the first side lip 122 constitute a labyrinth seal.

In the inner side seal member 10, the inner fitting portion 11a, the protruding portion 14c, and the first side lip 122 are positioned on the outer peripheral portion of the inner side seal member 10, and the inner fitting portion 11a, the protruding portion 14c, and the first side lip 122 are arranged. By forming a labyrinth seal with the side lip 122, it is possible to suppress the intrusion of muddy water into the inner side seal member 10 and improve the muddy water resistance performance.

In particular, in the inner side seal member 10, the first side lip 122 is provided in a non-contact state with respect to the annular portion 14b of the slinger 4, and in addition between the inner fitting portion 11a and the projecting portion 14c, Since a labyrinth seal is formed between the first side lip 122 and the annular portion 14b, it is possible to improve muddy water resistance performance while suppressing an increase in seal torque in the inner side seal member 10. .

In this way, when the labyrinth seal is formed in the inner side seal member 10 to suppress the intrusion of muddy water, once muddy water enters the labyrinth seal, it tends to be difficult to be discharged to the outside. Therefore, in the inner side seal member 10, a drain portion 13A is formed in the seal member 13 so that even if muddy water enters the labyrinth seal, the muddy water can be easily discharged.

[Drain part]
As shown in FIG. 3, the drain portion 13A is formed in a predetermined region in the circumferential direction on the road surface side of the seal member 13. As shown in FIG. In the case of this embodiment, the drain portion 13A is positioned at the lowest portion of the seal member 13 and is formed in the region of the angle θ in the circumferential direction of the seal member 13 . That is, the drain portion 13A is formed within an angle θ around the lower end PL1 of the seal member 13 in the circumferential direction. The angle θ can be set within a range of 45° or less.

As shown in FIGS. 2(b) and 3, in the region where the drain portion 13A of the seal member 13 is formed, the inner fitting portion 11a of the cored bar 11 is notched toward the outer side in the axial direction. A portion 111 is formed. The cutout portion 111 is formed so that its axial length is shorter than the other portion of the inner fitting portion 11a. Located on the outer side.

In the drain portion 13A, the notch portion 111 of the inner fitting portion 11a and the projecting portion 14c of the slinger 14 do not overlap when viewed in the radial direction. That is, in the drain portion 13A, the inner fitting portion 11a is notched in the axial direction to a position where it does not overlap the projecting portion 14c of the slinger 14 when viewed in the radial direction. There is a gap d3 between them.

By forming the drain portion 13A in the seal member 13 in this manner, even when muddy water enters the interior of the inner side seal member 10, the infiltrated muddy water flows downward due to gravity, and the protruding portion 14c of the drain portion 13A. and the notch 111 to the outside of the inner side seal member 10. As shown in FIG. In particular, since the notch 111 is notched in the axial direction to a position that does not overlap with the projecting portion 14c, muddy water that has entered the inner side seal member 10 is more easily discharged to the outside.

As a result, even when the protruding portion 14c of the slinger 14 is used to form a labyrinth seal in the inner side seal member 10, it is possible to effectively improve the muddy water resistance performance. Further, in the inner side seal member 10, since a labyrinth seal is formed at a portion other than the portion where the drain portion 13A is formed, sealing performance can be ensured.

Further, the wheel bearing device 1 is mounted on the vehicle with the wheel bearing device 1 supporting the left wheel and the wheel bearing device 1 supporting the right wheel out of phase with each other in the circumferential direction. may be installed. However, in the inner side seal member 10, the drain portion 13A is formed in the range of angle θ around the lower end PL of the seal member 13 in the circumferential direction, and the angle θ is set to a maximum of 45°. In both the wheel bearing device 1 that supports the left wheel and the wheel bearing device 1 that supports the right wheel, the drain portion 13A can be positioned at the lower end of the inner side seal member 10. Versatility of muddy water performance can be increased.

[Discharge part]
In the wheel bearing device 1, by forming the drain portion 13A in the seal member 13 of the inner side seal member 10, muddy water that has entered the inner side seal member 10 can be easily discharged to the outside. ing. However, as shown in FIG. 4, if the inner peripheral surface of the inner side opening 2a of the outer ring 2 protrudes greatly below the drain portion 13A, the muddy water W discharged to the outside of the inner side seal member 10 may There is a risk that the muddy water will accumulate on the inner peripheral surface of the opening 2a and prevent further muddy water from being discharged. Therefore, in the wheel bearing device 1, in addition to the drain portion 13A of the seal member 13, the inner side opening portion 2a of the outer ring 2 is formed with a discharge portion 2A.

As shown in FIG. 3, the discharge portion 2A is formed in a predetermined region in the circumferential direction on the road surface side of the inner side opening 2a of the outer ring 2. As shown in FIG. In the case of this embodiment, the discharge portion 2A is positioned at the lowest portion of the inner side opening 2a and is formed in a region of an angle θ in the circumferential direction of the inner side opening 2a.

In addition, the discharge portion 2A is formed in the same area as the drain portion 13A in the circumferential direction. In other words, the discharge portion 2A is formed within the range of an angle θ around the lower end PL2 of the inner side opening portion 2a in the circumferential direction. The angle θ can be set within a range of 45° or less.

As shown in FIGS. 2(b) and 3, in the region of the inner side opening 2a where the discharge portion 2A is formed, the inner side opening 2a is notched toward the outer side in the axial direction to form a notch portion. 21 is formed. The cutout portion 21 is formed so that its axial length is shorter than the other portion of the inner side opening portion 2a, and the inner side end of the cutout portion 21 corresponds to the inner side end of the other portion of the inner side opening portion 2a. It is located on the outer side. In addition, the notch 21 is formed over the entire inner side opening 2a in the radial direction.

By forming the discharge portion 2A in the inner side opening portion 2a of the outer ring 2 in this way, muddy water discharged from the drain portion 13A to the outside of the inner side seal member 10 flows downward through the discharge portion 2A by gravity. , is easily discharged to the outside of the wheel bearing device 1 . As a result, even when the protruding portion 14c of the slinger 14 is used to form a labyrinth seal in the inner side seal member 10, it is possible to more effectively improve the muddy water resistance performance.

In addition, since the discharge portion 2A formed in the outer ring 2, which is a fixed ring, is formed in the same region in the circumferential direction as the region in which the drain portion 13A is formed, the seal member 13 is disposed in the inner side opening of the outer ring 2. 2a, the phase of the drain portion 13A of the seal member 13 and the phase of the discharge portion 2A of the inner side opening 2a can be matched. In this way, when the sealing member 13 is assembled to the outer ring 2, it is possible to prevent incorrect assembly of the sealing member 13 by using the discharge portion 2A of the outer ring 2 as a position reference for assembly.

In addition, in the discharge portion 2A, the inner side end of the notch portion 21 is located on the inner side by a distance d4 from the inner side end of the notch portion 111 in the drain portion 13A. That is, the notch 21 of the inner side opening 2a is axially cut away from the notch 111 of the inner fitting portion 11a to the ring portion 14b side of the slinger 14. As shown in FIG.

In this way, the inner side end of the notch 21 in the discharge portion 2A protrudes further toward the inner side than the inner side end of the notch 111 in the drain portion 13A. Since the elastic member 12 joined to the outer surface is not exposed to the outside, it is possible to suppress the elastic member 12 from being damaged by an external force.

Further, similarly to the drain portion 3A, the discharge portion 2A is formed in a range of angle θ around the lower end PL of the seal member 13 in the circumferential direction, and the angle θ is set to a maximum of 45°. In both the wheel bearing device 1 that supports the wheel on the right side and the wheel bearing device 1 that supports the right wheel, the discharge part 2A can be positioned at the lower end of the wheel bearing device 1, and is resistant to muddy water. Versatility of performance can be enhanced.

[Another embodiment of the inner side sealing member]
In the inner side seal member 10 described above, the first side lip 122 of the elastic member 12 is a non-contact lip facing the annular portion 14b of the slinger 14 with a gap d1, but it can also be formed as a contact lip. be.

The inner side seal member 30 shown in FIG. 5 has an elastic member 32 in place of the elastic member 12, and other configurations are the same as those of the inner side seal member 10. As shown in FIG. The inner side seal member 30 includes a seal member 33 and a slinger 14 , and the seal member 33 has a metal core 11 and an elastic member 32 .

The seal member 33 has a base portion 321 , a first side lip 322 , a second side lip 323 and a grease lip 324 . The base portion 321, the second side lip 323, and the grease lip 324 are configured similarly to the base portion 121, the second side lip 123, and the grease lip 124, respectively.

The first side lip 322 extends from the base portion 321 and has an annular shape. The first side lip 322 is a seal lip that the elastic member 32 has. The first side lip 322 is located on the outermost diameter side among the seal lips of the elastic member 32 and extends from the base portion 321 toward the outer diameter side and the inner side. The projecting portion 14c is positioned between the inner fitting portion 11a of the cored bar 11 and the first side lip 322 of the elastic member 32 in the radial direction.

The first side lip 322 of the elastic member 32 faces the annular portion 14b of the slinger 14 in the axial direction. The tip of the first side lip 322 is in slidable contact with the annular portion 14b, and the first side lip 322 is a contact lip.

As described above, even in the inner side seal member 30 in which the first side lip 322 of the elastic member 32 is a sliding contact lip, the inner fitting portion 11a of the metal core 11 of the seal member 33 and the projecting portion 14c of the slinger 14 have a diameter They overlap each other when viewed from the direction, and the inner fitting portion 11a and the projecting portion 14c constitute a labyrinth seal. As a result, it is possible to suppress the intrusion of muddy water into the inner side seal member 30 and improve the muddy water resistance performance.

Furthermore, in the inner side seal member 30, a drain portion 33A having a configuration similar to that of the drain portion 13A can be formed. It is possible to effectively improve muddy water resistance performance by making it easier to discharge.

The configuration of the drain portion 13A in the inner side seal member 30 can also be applied to an outer side seal member provided at the outer side end portion of the wheel bearing device. Further, the configuration of the discharge portion 2A in the outer ring 2 can also be applied to the outer side opening of the outer ring in which the outer side seal member is fitted. When the configuration of the drain portion 13A and the discharge portion 2A is applied to the outer side, the outer side is the one end side in the axial direction, and the inner side is the other end side in the axial direction.

Further, the wheel bearing device 1 in this embodiment is configured as a wheel bearing device 1 of a third-generation structure in which the inner raceway surface 3c is directly formed on the outer periphery of the hub wheel 3, but is limited to this. Instead, a second-generation structure in which a pair of inner rings 4 are press-fitted and fixed to the hub wheel 3 may be used.

Although the embodiments of the present invention have been described above, the present invention is not limited to such embodiments in any way, and is merely an example. Of course, the scope of the present invention is indicated by the description of the claims, and the meaning of equivalents described in the claims and all changes within the scope include.

1 Wheel bearing device 2 Outer ring 2A Discharge part 2a Inner side opening 2b Outer side opening 2c (Inner side) Outer raceway surface 2d (Outer side) Outer raceway surface 3 Hub wheel 3b Wheel mounting flange 3c Inner raceway surface 4 Inner ring 4a Inner raceway surface 5 Inner-side ball row 6 Outer-side ball row 10 Inner-side seal member 11 Core metal 11a Inner fitting portion 11b Side plate portion 12 Elastic member 13 Seal member 13A Drain portion 14 Slinger 14b Annular portion 14c Protruding portion 21 Notch Part 111 Notch 122 First side lip 123 Second side lip PL1 Lower end (of seal member) PL2 Lower end (of inner side opening) θ Angle

Claims (7)

an outer member having a double-row outer raceway surface on its inner circumference;
A double-row inner raceway surface facing the double-row outer raceway surface, comprising a hub wheel having a small-diameter stepped portion extending axially on its outer periphery, and at least one inner ring press-fitted into the small-diameter stepped portion of the hub wheel. an inner member having
a double-row rolling element rollably accommodated between the raceway surfaces of the outer member and the inner member;
A wheel bearing device comprising: a sealing device for closing an open end on one axial end side of an annular space formed by the outer member and the inner member,
The sealing device is
a core metal comprising an inner fitting portion fitted to the inner periphery of the outer member and a side plate portion extending radially inward from the other axial end of the inner fitting portion; and integrally joined to the core metal. a seal member having an elastic member that
an outer fitting portion fitted to the outer periphery of the inner member; an annular portion extending radially outward from one axial end of the outer fitting portion and facing the side plate portion in the axial direction; a slinger having a protruding portion that protrudes from the outer diameter side end portion of the slinger toward the side plate portion and faces the side plate portion with a gap,
the inner fitting portion of the seal member and the protruding portion of the slinger overlap when viewed in a radial direction;
The wheel bearing device, wherein the seal member has a drain portion formed by cutting the inner fitting portion in the axial direction in a predetermined region on the road surface side in the circumferential direction. 2. The wheel bearing device according to claim 1, wherein in the drain portion, the inner fitting portion is axially cut to a position where it does not overlap with the projecting portion. 3. The wheel bearing device according to claim 1, wherein the drain portion is formed within a range of 45 degrees around the lower end of the seal member in the circumferential direction. The outer member is
a fitted portion to which the inner fitting portion is fitted;
The drain portion according to any one of claims 1 to 3, wherein the fitted portion is axially notched in the same region as the region in which the drain portion is formed in the circumferential direction. Wheel bearing device. 5. The wheel bearing device according to claim 4, wherein in the discharge portion, the fitted portion is axially cut away from the inner fitting portion of the drain portion to the annular portion side. 6. The wheel bearing device according to claim 4, wherein the discharge portion is formed within a range of 45 degrees around the lower end of the seal member in the circumferential direction. The elastic member has a plurality of seal lips extending toward the annular portion of the slinger,
Among the plurality of seal lips, the outermost seal lip located on the outermost diameter side is provided in a non-contact state with the slinger,
The wheel bearing device according to any one of claims 1 to 6, wherein a tip end surface of the outermost seal lip is located closer to the annular portion than the side plate portion side end of the projecting portion. .

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