Sealing device and wheel bearing device comprising the same

Abstract

To provide a sealing device that can restrain a foreign body in a labyrinth from reaching a lip part.SOLUTION: A sealing device (inner side seal member 9) comprises a slinger 30, and a seal ring 40. The seal ring 40 comprises a metal core 41, and a wall member 43 continuous with a second wall part 41c of the metal core 41. A gap between an outer plate part 33 of the slinger 30 and the metal core 41 is constituted as a labyrinth 50. A gap between the slinger 30 and the second wall part 41c of the metal core 41, and a gap between the slinger 30 and the wall member 43 are constituted as a first space 61. In the first space 61, at least one lip part 47 is in contact with the slinger 30. A space surrounded by a first wall part 41b and the second wall part 41c of the metal core 41, and the wall member 43 is constituted as a second space 62. The labyrinth 50 is continuous with each of the first space 61 and the second space 62.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a sealing device that seals an opening of a space between an outer member and an inner member, and to a wheel bearing device equipped with the sealing device. [Background technology]

[0002] Double-row angular contact ball bearings have been commonly used as bearing assemblies for automobile wheels. Various types of wheel bearing assemblies are known, each comprising an outer member having double-row outer raceway grooves on its inner periphery, a hub ring having a small-diameter stepped portion at the inner end of its outer periphery, and an inner ring provided on the small-diameter stepped portion of the hub ring, the inner member having double-row inner raceway grooves facing the double-row outer raceway grooves, and a sealing device that seals the opening of the bearing space between the outer member and the inner member. The sealing device for the automobile wheel bearing assemblies includes a slinger fitted onto the inner member and a seal ring fitted into the outer member, and the lip of the seal ring that contacts the slinger prevents foreign matter, such as muddy water, that has entered the sealing device from further penetrating into the bearing space.

[0003] Also, a sealing device used in a bearing device for a wheel support of an automobile or the like is known, which is configured by combining a first seal member fitted inside an outer member and a double-cylindrical second seal member fitted outside an inner member, with inner and outer cylindrical portions of the second seal member formed to extend axially toward the first seal member, and the outer cylindrical portion forming an axial labyrinth between itself and the portion of the first seal member that is fitted inside the outer member (see Patent Document 1). In this sealing device, the labyrinth between itself and the portion of the first seal member that is fitted inside the outer member prevents foreign matter from reaching the lip portion. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6381120 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in a sealing device used in a bearing device for a wheel support portion of an automobile or the like, if foreign matter in the labyrinth further penetrates into the sealing device, the foreign matter may enter the contact portion between the lip portion and the second seal member. If the foreign matter enters the contact portion between the lip portion and the second seal member, the lip portion may deteriorate, potentially reducing the sealing performance of the sealing device. Therefore, there is a need to further prevent foreign matter in the labyrinth from reaching the lip portion.

[0006] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a sealing device that can prevent foreign matter in the labyrinth from reaching the lip portion. [Means for solving the problem]

[0007] That is, a sealing device including a slinger and a seal ring, The slinger is an outer fitting portion that is fitted onto the inner member; a middle plate portion extending radially outward from the outer fitting portion; an outer plate portion extending in the axial direction from the middle plate portion located radially outward of the outer fitting portion, The seal ring is a core bar including an inner fitting portion that is fitted into an outer member, a first wall portion that extends radially inward from the inner fitting portion, and a second wall portion that extends axially from the first wall portion that is located radially outward from the inner fitting portion toward the middle plate portion of the slinger; an elastic member having a lip portion that contacts the slinger; a wall member continuous with an end portion of the second wall portion of the core metal on the side of the middle plate portion of the slinger, A gap between the outer plate portion of the slinger and the core metal is configured as a labyrinth, a gap between the slinger and the second wall portion of the core metal and a gap between the slinger and the wall member are configured as a first space, and at least one of the lip portions contacts the slinger in the first space; a space surrounded by the first wall portion of the core bar, the second wall portion of the core bar, and the wall member is configured as a second space, The labyrinth is continuous with the first space and the second space. [Effects of the Invention]

[0008] The present invention has the following effects. That is, according to the sealing device of the present invention, it is possible to prevent foreign matter in the labyrinth from reaching the lip portion. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing a wheel bearing assembly in which a sealing device according to an embodiment of the present invention is used; [Figure 2] FIG. 4 is an enlarged cross-sectional view of a portion of the wheel bearing assembly where a sealing device is disposed. [Figure 3] FIG. 4 is an enlarged cross-sectional view of a portion of the wheel bearing assembly where a sealing device is disposed. [Figure 4] FIG. 2 is an enlarged cross-sectional view showing a sealing device according to an embodiment of the present invention. [Figure 5] FIG. [Figure 6] FIG. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. 10 is an enlarged cross-sectional view of the boundary portion between the core metal and the wall member of the sealing device as viewed from the inner side. [Figure 10] FIG. 10 is an enlarged cross-sectional view of the boundary portion between the core metal and the wall member of the sealing device as viewed from the inner side. [Figure 11]FIG. 10 is an enlarged cross-sectional view of the boundary portion between the core metal and the wall member of the sealing device as viewed from the inner side. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0011] [Wheel bearing device] A wheel bearing device 1 shown in FIG. 1 uses a sealing device according to the present invention, and supports a wheel rotatably in a suspension system of a vehicle such as an automobile.

[0012] 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 (raceway groove forming members) as inner members, two rolling rows of inner ball rows 5 and outer ball rows 6, an inner seal member 9, and an outer seal member 10.

[0013] 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 end side being the outer side and the other axial end 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.

[0014] 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. Bolt holes 2f are provided in the vehicle body mounting flange 2e, into which fastening members (here, bolts) are inserted to fasten the outer ring 2 to the vehicle body member.

[0015] 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. 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. Hub bolts for fastening the hub wheel 3 to a wheel or brake component are press-fitted into the bolt holes 3d. The wheel mounting flange 3b is an example of a hub flange that extends radially outward.

[0016] An outer-side inner raceway groove 3c is provided on the outer peripheral surface of the hub wheel 3 so as to face the outer raceway groove 2d on the outer side of the outer ring 2. In other words, the hub wheel 3 defines the inner raceway groove 3c on the outer side of the inner member.

[0017] The inner ring 4 is mounted on the small diameter step 3a of the hub ring 3. The inner ring 4 is press-fitted into the small diameter step 3a via a specified interference. Furthermore, the hub ring 3 and the inner ring 4 are integrated by a crimped portion 3h, which is plastically deformed by crimping the inner end of the small diameter step 3a of the hub ring 3, 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 form the rolling rows. An inner-side inner raceway groove 4a is formed on the outer peripheral surface of the inner ring 4 so as to face the inner-side outer raceway groove 2c of the outer ring 2. In other words, the inner ring 4 defines the inner raceway groove 4a on the inner side of the inner member.

[0018] A bearing space, which is an annular space, is formed between the outer ring 2 and the hub wheel 3. An outer seal member 10 is fitted into the outer end of the bearing space to prevent foreign matter such as muddy water from entering through the outer opening 2b. The outer seal member 10 is an example of a sealing device.

[0019] An inner seal member 9 is fitted into the inner end of the bearing space between the outer ring 2 and the inner ring 4 to prevent foreign matter such as muddy water from entering through the inner opening 2a. The inner seal member 9 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. 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] [Specific configuration of inner seal member] The inner seal member 9 is an embodiment of the sealing device according to the present invention. The inner seal member 9 includes a slinger 30 and a seal ring 40.

[0022] The slinger 30 is a ring-shaped body made of, for example, a steel plate, and is fitted onto the inner ring 4. The slinger 30 includes an outer fitting portion 31, a middle plate portion 32, an outer plate portion 33, and a magnetic encoder 34. The outer fitting portion 31 is a cylindrical portion fitted onto the radially outer surface of the inner end portion of the inner ring 4. The middle plate portion 32 is located radially outward from the outer fitting portion 31. The middle plate portion 32 is a donut-shaped portion extending radially outward from the inner end portion of the outer fitting portion 31. The outer plate portion 33 is located radially outward from the outer fitting portion 31 and the middle plate portion 32. The outer plate portion 33 is a cylindrical portion extending from the radially outer end portion of the middle plate portion 32 toward the outer side (the side where the first wall portion 41b of the core metal 41 is located in the axial direction). In this way, the cross section of the slinger 30 is configured to be approximately J-shaped.

[0023] The magnetic encoder 34 is made of synthetic rubber or the like with an arrangement of magnetic poles (north and south poles) and is configured in a doughnut plate shape. The magnetic encoder 34 is joined to the slinger 30 by vulcanization bonding or the like. The magnetic encoder 34 is provided so as to cover the inner side surface of the middle plate portion 32 of the slinger 30, the radially outer side surface of the outer plate portion 33, the outer end portion of the outer plate portion 33, the radially inner side surface of the outer plate portion 33, and a portion of the outer side surface of the middle plate portion 32.

[0024] The magnetic encoder 34 is configured as part of the slinger 30. That is, the inner side surface of the portion of the magnetic encoder 34 that covers the middle plate 32 of the slinger 30 indicates the inner side surface of the middle plate 32 of the slinger 30, and the radially outer side surface of the portion of the magnetic encoder 34 that covers the radially outer side of the outer plate 33 of the slinger 30 indicates the radially outer side surface of the outer plate 33 of the slinger 30. Furthermore, the outer side surface of the portion of the magnetic encoder 34 that covers the outer end of the outer plate 33 of the slinger 30 indicates the outer end of the outer plate 33 of the slinger 30, and the portion of the magnetic encoder 34 that covers the radially inner side surface of the outer plate 33 of the slinger 30 indicates the radially inner side surface of the outer plate 33 of the slinger 30. Furthermore, the outer side surface of the portion of the magnetic encoder 34 that covers the middle plate 32 of the slinger 30 and the portion of the outer side surface of the middle plate 32 that is not covered by the magnetic encoder 34 indicate the outer side surface of the middle plate 32 of the slinger 30.

[0025] The magnetic encoder 34 is not limited to being configured as described above, and may be configured, for example, to be disposed only on the inner side surface of the middle plate portion 32 of the slinger 30 (see FIG. 4). Also, for example, the magnetic encoder 34 may be configured to cover the inner side surface of the middle plate portion 32 of the slinger 30, the radially outer side surface of the outer plate portion 33, and the outer end portion of the outer plate portion 33 (see FIG. 5). The slinger 30 may also be configured without the magnetic encoder 34.

[0026] The seal ring 40 of the inner seal member 9 is fitted into the outer ring 2. The seal ring 40 includes a core metal 41, a wall member 43, and an elastic member 45.

[0027] The core metal 41 of the seal ring 40 is a ring-shaped member made of, for example, a steel plate, and includes an inner fitting portion 41a, a first wall portion 41b, a second wall portion 41c, and a seal member 42. The inner fitting portion 41a is a cylindrical portion that is fitted into the radially inner surface of the inner end portion of the outer ring 2. The first wall portion 41b is located radially inward of the inner fitting portion 41a. The first wall portion 41b is a donut-shaped portion that extends radially inward from the outer end portion of the inner fitting portion 41a. The second wall portion 41c is located radially inward of the inner fitting portion 41a and the first wall portion 41b. The second wall portion 41c is a cylindrical portion that extends from the radially inner end portion of the first wall portion 41b toward the inner side (the side where the middle plate portion 32 of the slinger 30 is disposed in the axial direction). In this way, the cross section of the core metal 41 is configured to be approximately J-shaped.

[0028] A predetermined gap is formed between the radially outer surface of the outer plate portion 33 of the slinger 30 and the radially inner surface of the inner fitting portion 41a of the core 41, and a predetermined gap is formed between the radially outer surface of the outer fitting portion 31 of the slinger 30 and the radially inner surface of the second wall portion 41c of the core 41. In this way, the core 41 and the slinger 30 are configured to be non-contact with each other.

[0029] The seal member 42 is made of, for example, synthetic rubber and is configured to be elastically deformable. The seal member 42 contacts the radially inner surface of the inner end of the outer ring 2 to prevent foreign matter such as muddy water from entering between the outer ring 2 and the inner fitted portion 41a of the core bar 41. The seal member 42 is joined to the core bar 41 by vulcanization bonding or the like. The seal member 42 is provided so as to cover a portion of the radially outer surface of the inner fitted portion 41a of the core bar 41, the inner end of the inner fitted portion 41a, the radially inner surface of the inner fitted portion 41a, and a portion of the inner side surface of the first wall portion 41b.

[0030] The seal member 42 is configured as a part of the core metal 41. That is, the radially outer surface of the portion of the seal member 42 that covers the inner fitting portion 41a and the portion of the radially outer surface of the inner fitting portion 41a that is not covered by the seal member 42 indicate the radially outer surface of the inner fitting portion 41a of the core metal 41. Furthermore, the inner end of the portion of the seal member 42 that covers the inner fitting portion 41a indicates the inner end of the inner fitting portion 41a of the core metal 41, and the radially inner surface of the portion of the seal member 42 that covers the inner fitting portion 41a indicates the radially inner surface of the inner fitting portion 41a of the core metal 41. Furthermore, the inner side surface of the portion of the seal member 42 that covers the first wall portion 41b and the portion of the inner side surface of the first wall portion 41b that is not covered by the seal member 42 indicate the inner side surface of the first wall portion 41b of the core metal 41.

[0031] It should be noted that the sealing member 42 is not limited to being configured in this manner, and may be configured, for example, to be disposed only on the radially outer surface of the inner fitting portion 41a of the core bar 41. Furthermore, for example, the sealing member 42 may be configured to be disposed on the radially outer surface of the inner fitting portion 41a of the core bar 41 and on the inner side end portion of the inner fitting portion 41a, or on the radially outer surface of the inner fitting portion 41a of the core bar 41, the inner side end portion of the inner fitting portion 41a, and the radially outer surface of the inner fitting portion 41a.

[0032] The wall member 43 is, for example, a circular ring made of a steel plate, and is disposed so as to be continuous with the core metal 41. The wall member 43 includes a third wall portion 43a and a fourth wall portion 43b. The third wall portion 43a is located radially inward of the inner fitting portion 41a of the core metal 41 and radially outward of the second wall portion 41c of the core metal 41. The third wall portion 43a is a donut-shaped portion extending radially outward from the inner end of the second wall portion 41c of the core metal 41. The fourth wall portion 43b is located radially inward of the inner fitting portion 41a of the core metal 41 and radially outward of the third wall portion 43a and the second wall portion 41c of the core metal 41. The fourth wall portion 43b is a cylindrical portion extending from the radially outer end of the third wall portion 43a to the outer side (the side opposite to the side on which the middle plate portion 32 of the slinger 30 is disposed in the axial direction). In this way, the cross section of the wall member 43 is configured to be approximately L-shaped. The axial position of the outer end of the fourth wall portion 43b of the wall member 43 is configured to be approximately the same as the axial position of the outer end of the outer plate portion 33 of the slinger 30.

[0033] A predetermined gap is formed between the outer side surface of the middle plate portion 32 of the slinger 30 and the inner side surface of the third wall portion 43a of the wall member 43, and a predetermined gap is formed between the radially inner side surface of the outer plate portion 33 of the slinger 30 and the radially outer side surface of the fourth wall portion 43b of the wall member 43. In this way, the wall member 43 and the slinger 30 are configured to be non-contact with each other.

[0034] Note that the wall member 43 is not limited to being configured in this manner, and may be configured of, for example, synthetic rubber. The wall member 43 may also be configured as an integral part of the core metal 41. The third wall portion 43a and the fourth wall portion 43b of the wall member 43 may also be configured as separate bodies. The axial position of the outer-side end portion of the fourth wall portion 43b of the wall member 43 may also be configured to be located on the outer or inner side of the axial position of the outer-side end portion of the outer plate portion 33 of the slinger 30. The cross section of the wall member 43 may also be configured to be, for example, arc-shaped.

[0035] The elastic member 45 of the seal ring 40 is made of, for example, synthetic rubber, and is joined to the core metal 41 by vulcanization adhesion or the like. The elastic member 45 includes a base portion 46 and a lip portion 47.

[0036] The base 46 of the elastic member 45 is provided so as to cover a part of the outer side surface of the first wall portion 41b of the core metal 41, the radially inner side surface of the second wall portion 41c, and a part of the inner side surface of the wall member 43. By configuring the base 46 in this manner, the core metal 41 and the wall member 43 are integrally configured. However, the base 46 is not limited to being configured in this manner, and can also be configured integrally so as to be continuous with the seal member 42 of the core metal 41, for example.

[0037] The lip portion 47 of the elastic member 45 is configured to be elastically deformable and contacts the slinger 30 to prevent foreign matter such as muddy water from entering between the slinger 30 and the seal ring 40. The lip portion 47 includes one side lip 47a and one radial lip 47b.

[0038] The side lip 47a of the lip portion 47 extends radially outward and inward from the base portion 46. The tip of the side lip 47a contacts the outer side surface of the mid-plate portion 32 of the slinger 30. The radial lip 47b extends radially inward and outward from the base portion 46. The tip of the radial lip 47b contacts the radially outer surface of the outer fitting portion 31 of the slinger 30.

[0039] The inner seal member 9 includes a labyrinth 50 , a first space 61 , a second space 62 , and a branch space 63 .

[0040] The gap between the outer plate portion 33 of the slinger 30 and the inner fitting portion 41a of the core metal 41 is configured as a labyrinth 50. The labyrinth 50 includes a first labyrinth 51, a second labyrinth 52, a first opening 53, and a second opening 54. The first labyrinth 51 is configured as a space formed between the radially outer surface of the outer plate portion 33 of the slinger 30 and the radially inner surface of the inner fitting portion 41a of the core metal 41. The second labyrinth 52 is configured as a space formed between the outer end of the outer plate portion 33 of the slinger 30 and the inner side surface of the first wall portion 41b of the core metal 41. The first opening 53 is configured as an inner end of the first labyrinth 51. The second opening 54 is configured as a radially inner end of the second labyrinth 52.

[0041] The gap between the slinger 30 and the second wall portion 41c of the core bar 41 and the gap between the slinger 30 and the wall member are defined as a first space 61. The first space 61 is defined by a gap between the radially outer surface of the outer fitting portion 31 of the slinger 30 and the radially inner surface of the second wall portion 41c of the core bar 41, a gap between the outer side surface of the middle plate portion 32 of the slinger 30 and the inner side surface of the third wall portion 43a of the wall member 43, and a gap between the radially inner surface of the outer plate portion 33 of the slinger 30 and the radially outer surface of the fourth wall portion 43b of the wall member 43. The first space 61 is defined as a space in which the lip portion 47 contacts at least one of the outer fitting portion 31 and the middle plate portion 32 of the slinger 30. In the first space 61, at least one of the multiple lips (side lip 47a and radial lip 47b) of the lip portion 47 of the elastic member 45 contacts the slinger 30. The first space 61 has a first flow port 61a. The first flow port 61a is configured at the outer end of the first space 61.

[0042] The space surrounded by the first wall portion 41b of the core 41 of the seal ring 40, the second wall portion 41c of the core 41, the third wall portion 43a of the wall member 43, and the fourth wall portion 43b of the wall member 43 is configured as a second space 62. The second space 62 is configured as a space in which the lip portion 47 does not contact the slinger 30. The second space 62 has a second circulation port 62a. The second circulation port 62a is configured as a space between the first wall portion 41b of the core 41 and the outer end portion of the fourth wall portion 43b of the wall member 43. The cross section of the second space 62 is configured as a substantially square shape.

[0043] The branch space 63 is defined by a space surrounded by the first opening 53, the first wall portion 41b of the core 41, the first flow port 61a, and the second flow port 62a. The labyrinth 50 is connected to the branch space 63 via the first opening 53. The first space 61 is connected to the branch space 63 via the first flow port 61a. The second space 62 is connected to the branch space 63 via the second flow port 62a. That is, the labyrinth 50 is connected to the first space 61 and the second space 62 via the branch space 63.

[0044] As described above, the gap between the outer plate portion 33 of the slinger 30 and the inner fitting portion 41a of the core 41 of the seal ring 40 is configured as a labyrinth 50. The gap between the slinger 30 and the second wall portion 41c of the core 41 and the gap between the slinger 30 and the wall member 43 are configured as a first space 61 with which the lip portion 47 of the elastic member 45 comes into contact. The space surrounded by the first wall portion 41b of the core 41, the second wall portion 41c of the core 41, and the wall member 43 is configured as a second space 62 in which the lip portion 47 of the elastic member 45 does not come into contact with the slinger 30. Furthermore, the labyrinth 50 is continuous with the first space 61 and the second space 62, respectively. With this configuration, when foreign matter in the labyrinth 50 further infiltrates into the inner-side seal member 9, the foreign matter will infiltrate separately into the first space 61 where the lip portion 47 of the elastic member 45 is disposed and the second space 62 where the lip portion 47 of the elastic member 45 is not disposed. This reduces the amount of foreign matter that infiltrates into the first space 61, and prevents the foreign matter from reaching the lip portion 47 of the elastic member 45. This allows the inner-side seal member 9 to maintain its sealing performance at the inner-side opening 2a.

[0045] As described above, the first space 61 is made up of the gap between the radially outer surface of the outer fitting portion 31 of the slinger 30 and the radially inner surface of the second wall portion 41c of the core metal 41, the gap between the outer side surface of the middle plate portion 32 of the slinger 30 and the inner side surface of the third wall portion 43a of the wall member 43, and the gap between the radially inner surface of the outer plate portion 33 of the slinger 30 and the radially outer surface of the fourth wall portion 43b of the wall member 43. As a result of this configuration, the gap between the radially inner surface of the outer plate portion 33 of the slinger 30 and the radially outer surface of the fourth wall portion 43b of the wall member 43 is configured as the labyrinth 61b of the first space 61. The labyrinth 61b of the first space 61 prevents foreign matter from entering the space in which the lip portion 47 of the elastic member 45 is disposed, that is, the gap between the radially outer surface of the outer fitting portion 31 of the slinger 30 and the radially inner surface of the second wall portion 41c of the core metal 41, or the gap between the outer side surface of the middle plate portion 32 of the slinger 30 and the inner side surface of the third wall portion 43a of the wall member 43. In this way, foreign matter can be prevented from reaching the lip portion 47 of the elastic member 45.

[0046] As described above, the second space 62 is formed by a space surrounded by the first wall portion 41b of the core metal 41 of the seal ring 40, the second wall portion 41c of the core metal 41, the third wall portion 43a of the wall member 43, and the fourth wall portion 43b of the wall member 43. Because of this configuration, the second space 62 can be made wider, and the capacity for foreign matter to enter the second space 62 can be increased.

[0047] As described above, the labyrinth 50 is continuous with the first space 61 and the second space 62 via the branch space 63. With this configuration, when foreign matter in the labyrinth 50 further infiltrates into the inner seal member 9, it will infiltrate separately into the first space 61 and the second space 62, where the lip portion 47 of the elastic member 45 is not located. This reduces the amount of foreign matter that infiltrates into the first space 61, and prevents the foreign matter from reaching the lip portion 47 of the elastic member 45.

[0048] The opening area of ​​the second flow port 62a of the second space 62 is configured to be larger than the opening area of ​​the first flow port 61a of the first space 61. With this configuration, foreign matter is more likely to enter the second space 62 than the first space 61. Therefore, it is possible to prevent foreign matter from reaching the lip portion 47 of the elastic member 45.

[0049] The opening area of ​​the second flow port 62a of the second space 62 is configured to be larger than the opening area of ​​the second opening 54 of the labyrinth 50. With this configuration, foreign matter can enter the second space 62 relatively smoothly.

[0050] The second opening 54 of the labyrinth 50 opens radially inward, and the second circulation port 62a of the second space 62 opens radially outward. With this configuration, the flow direction of foreign matter flowing out from the second opening 54 of the labyrinth 50 and the flow direction of foreign matter flowing into the second space 62 from the second circulation port 62a are the same, allowing foreign matter to enter the second space 62 relatively smoothly. Furthermore, with this configuration, the flow direction of foreign matter flowing out from the second opening 54 of the labyrinth 50 and the flow direction of foreign matter flowing into the second space 62 from the second circulation port 62a are the same, causing foreign matter to flow toward the road surface due to the effect of gravity, making it easier for foreign matter in the second space 62 to be discharged toward the labyrinth 50 relatively smoothly.

[0051] The second flow port 62a of the second space 62 and the second opening 54 of the labyrinth 50 are configured to overlap when viewed from the radial direction. With this configuration, foreign matter flowing out from the second opening 54 of the labyrinth 50 can relatively smoothly enter the second space 62 from the second flow port 62a. Furthermore, with this configuration, the foreign matter flows toward the road surface due to the influence of gravity, and the foreign matter in the second space 62 can be relatively smoothly discharged toward the labyrinth 50.

[0052] The second opening 54 of the labyrinth 50 opens radially inward, and the first circulation port 61a of the first space 61 opens toward the inner side. Furthermore, the first circulation port 61a of the first space 61 and the second opening 54 of the labyrinth 50 are configured so as not to overlap when viewed radially or axially. With this configuration, the flow direction of foreign matter flowing out from the second opening 54 of the labyrinth 50 and the flow direction of foreign matter flowing into the first space 61 from the second circulation port 62a are perpendicular to each other, making it relatively difficult for foreign matter to enter the second space 61.

[0053] As described above, the lip portion 47 of the elastic member 45 includes one side lip 47a that contacts the middle plate portion 32 of the slinger 30 and one radial lip 47b that contacts the outer fitting portion 31 of the slinger 30. With this configuration, by reducing the number of lip portions 47 of the elastic member 45 that contact the slinger 30, low friction can be achieved.

[0054] As shown in Fig. 3, the lip portion 47 of the elastic member 45 can also be configured to include one side lip 47a that contacts the mid-plate portion 32 of the slinger 30. Also, as shown in Fig. 4, the lip portion 47 of the elastic member 45 can also be configured to include one radial lip 47b that contacts the outer fitting portion 31 of the slinger 30. In this way, the lip portion 47 of the elastic member 45 can also be configured to include either the side lip 47a that contacts the mid-plate portion 32 of the slinger 30 or the radial lip 47b that contacts the outer fitting portion 31 of the slinger 30. With this configuration, reducing the number of lip portions 47 of the elastic member 45 that contact the slinger 30 can achieve low friction.

[0055] 5, the lip portion 47 of the elastic member 45 can also be configured to include one radial lip 47c that contacts the outer fitting portion 31 of the slinger 30. The radial lip 47c extends radially inward and toward the inner side from the base portion 46. The tip of the radial lip 47c contacts the radially outer surface of the outer fitting portion 31 of the slinger 30. With this configuration, by reducing the number of lip portions 47 of the elastic member 45 that contact the slinger 30, low friction can be achieved.

[0056] 6, lip portion 47 of elastic member 45 can also be configured to include two radial lips 47b and 47c that contact outer fitting portion 31 of slinger 30. With this configuration, lip portion 47 of elastic member 45 that contacts slinger 30 has two radial lips and no side lips, thereby increasing the volume of the gap in first space 61 and preventing foreign matter from reaching lip portion 47 of elastic member 45.

[0057] As shown in FIG. 7 , the fourth wall portion 43b of the wall member 43 may be configured to extend radially outward from the radially outer end of the third wall portion 43a toward the outer side. In this case, the portion of the magnetic encoder 34 covering the radially inner surface of the outer plate portion 33 of the slinger 30 is configured to be inclined with respect to the axial direction so as to be parallel to the fourth wall portion 43b of the wall member 43. That is, the gap between the outer plate portion 33 of the slinger 30 and the fourth wall portion 43b of the wall member 43 in the first space 61 (the labyrinth 61b of the first space 61) is configured to be inclined with respect to the axial direction. With this configuration, foreign matter that has entered the first space 61 can be relatively smoothly discharged through the labyrinth 61b of the first space 61 toward the labyrinth 50 because the gap between the outer plate portion 33 of the slinger 30 and the fourth wall portion 43b of the wall member 43 in the first space 61 (the labyrinth 61b of the first space 61) is inclined with respect to the axial direction.

[0058] 8, the radially inner end of the third wall portion 43a of the wall member 43 can be configured to extend radially inward beyond the second wall portion 41c of the core metal 41 and bend outward to engage with the second wall portion 41c of the core metal 41. With this configuration, the wall member 43 can be more reliably maintained in a state where it is attached to the core metal 41.

[0059] 9, a plurality of convex portions 43e projecting radially inward are formed at the radially inner end portion of the third wall portion 43a of the wall member 43, and the boundary portion between the second wall portion 41c of the cored bar 41 and the third wall portion 43a of the wall member 43 is covered with the base portion 46 of the elastic member 45, and the base portion 46 of the elastic member 45 is provided between the plurality of convex portions 43e. With this configuration, the wall member 43 can be more reliably maintained in a state where it is attached to the cored bar 41.

[0060] 10, a plurality of through holes 43d penetrating in the axial direction are formed near the radially inner end of the third wall portion 43a of the wall member 43, and the boundary portion between the second wall portion 41c of the core metal 41 and the third wall portion 43a of the wall member 43 is covered with the base portion 46 of the elastic member 45, and the base portion 46 of the elastic member 45 is provided in the through hole 43d. With this configuration, the state in which the wall member 43 is attached to the core metal 41 can be more reliably maintained.

[0061] 11, a plurality of convex portions 43f projecting radially inward are formed at a radially inner end portion of the third wall portion 43a of the wall member 43, and a plurality of convex portions 41d projecting toward the inner side are formed at an inner end portion of the second wall portion 41c of the cored bar 41, so that the boundary portion between the second wall portion 41c of the cored bar 41 and the third wall portion 43a of the wall member 43 is covered with a base portion 46 of the elastic member 45, and the convex portions 43f of the third wall portion 43a and the convex portions 41d of the second wall portion 41c are engaged with each other. With this configuration, the wall member 43 can be more reliably maintained attached to the cored bar 41.

[0062] Although a so-called third-generation wheel bearing assembly has been exemplified, a wheel bearing assembly using the sealing device according to the present invention is not limited to this structure. For example, the wheel bearing assembly may have a first- or second-generation structure in which a pair of inner rings are press-fit into the small-diameter stepped portion of the hub ring. In another embodiment, an outer joint member of a CVJ having raceway grooves on its outer diameter, rather than an inner ring, may be used as the raceway groove-forming member constituting the inner member. Furthermore, while a double-row angular contact ball bearing with ball rows 5 and 6 as rolling elements has been exemplified, the present invention is not limited to this and may also be a double-row tapered roller bearing using tapered rollers as rolling elements. Furthermore, although the sealing device according to the present invention has been described as an inner-side sealing member, it may also be used as an outer-side sealing member.

[0063] 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]

[0064] 1 Wheel bearing device 2 outer ring 2a Inner side opening 2b Outer side opening 2c (inner side) outer raceway groove 2d (Outer side) outer raceway groove 2e Body mounting flange 2f bolt hole 3 Hub Wheel 3a Small diameter stepped section 3b Wheel mounting flange 3c Inner raceway groove 3d bolt holes 3h Fastening part 4 Inner ring (raceway groove forming member) 4a Inner raceway groove 5 Inner ball row 6 Outer ball row 7 Ball 8 Cage 9 Inner seal member 10 Outer seal member 30 Slinger 31 External fitting part 32 Middle plate 33 Outer panel part 34 Magnetic Encoder 40 Seal ring 41 Core 41a Inner fitting part 41b First wall part 41c Second wall section 42 Sealing material 43 Wall components 43a Third wall 43b Fourth wall 45 Elastic member 46 Base 47 Lip 47a Side lip 47b radial lip 47c radial lip 50 Labyrinth 51 First Labyrinth 52 Second Labyrinth 53 First opening 54 Second opening 61 First space 61a First outlet 61b Labyrinth 62 Second space 62a Second flow port 63 Branching Space

Claims

1. A sealing device comprising a slinger and a seal ring, The slinger is an outer fitting portion that is fitted onto the inner member; a middle plate portion extending radially outward from the outer fitting portion; an outer plate portion extending in the axial direction from the middle plate portion located radially outward of the outer fitting portion, The seal ring is a core bar including an inner fitting portion that is fitted into an outer member, a first wall portion that extends radially inward from the inner fitting portion, and a second wall portion that extends axially from the first wall portion that is located radially outward from the inner fitting portion toward the middle plate portion of the slinger; an elastic member having a lip portion that contacts the slinger; a wall member continuous with an end portion of the second wall portion of the core metal on the side of the middle plate portion of the slinger, A gap between the outer plate portion of the slinger and the core metal is configured as a labyrinth, a gap between the slinger and the second wall portion of the core metal and a gap between the slinger and the wall member are configured as a first space, and at least one of the lip portions contacts the slinger in the first space; a space surrounded by the first wall portion of the core bar, the second wall portion of the core bar, and the wall member is configured as a second space, The labyrinth is continuous with the first space and the second space, Sealing device.

2. the wall member includes a third wall portion extending radially outward from the second wall portion of the core metal, and a fourth wall portion extending from the third wall portion to a side of the slinger opposite to the middle plate portion side, The sealing device described in claim 1, wherein the first space is composed of a gap between the outer fitting portion of the slinger and the second wall portion of the core bar, a gap between the middle plate portion of the slinger and the third wall portion of the wall member, and a gap between the outer plate portion of the slinger and the fourth wall portion of the wall member.

3. The sealing device according to claim 2, wherein the second space is defined by a space surrounded by the first wall portion of the core metal, the second wall portion of the core metal, the third wall portion of the wall member, and the fourth wall portion of the wall member.

4. The sealing device according to claim 3 , wherein the lip portion comprises one side lip that contacts the mid-plate portion of the slinger and one radial lip that contacts the outer fitting portion of the slinger.

5. The sealing device according to claim 3 , wherein the lip portion comprises either a side lip that contacts the middle plate portion of the slinger or a radial lip that contacts the outer fitting portion of the slinger.

6. The sealing device of claim 3 , wherein the lip portion comprises two radial lips that contact the outer fitting portion of the slinger.

7. The sealing device according to claim 3 , wherein the gap between the outer plate portion of the slinger and the fourth wall portion of the wall member is configured to be inclined with respect to the axial direction.

8. A sealing device as described in claim 3, wherein the radially inner end of the third wall portion of the wall member is configured to extend radially inward more than the second wall portion of the core bar and bend toward the outer side, and engage with the second wall portion of the core bar.

9. 4. The sealing device according to claim 3, wherein a plurality of convex portions are formed on a radially inner end portion of the third wall portion of the wall member, the boundary portion between the second wall portion of the core metal and the third wall portion of the wall member is covered with the elastic member, and the elastic member is provided between the plurality of convex portions.

10. 4. The sealing device according to claim 3, wherein a plurality of through holes penetrating in the axial direction are formed near a radially inner end of the third wall portion of the wall member, and the boundary portion between the second wall portion of the core metal and the third wall portion of the wall member is covered with the elastic member, and the elastic member is provided in the through holes.

11. 4. A sealing device as described in claim 3, wherein a plurality of convex portions are formed on the radially inner end of the third wall portion of the wall member, a plurality of convex portions are formed on the inner end of the second wall portion of the core metal, the boundary portion between the second wall portion of the core metal and the third wall portion of the wall member is covered with the elastic member, and the convex portions of the third wall portion and the convex portions of the second wall portion are engaged with each other.

12. A wheel bearing device comprising the sealing device according to any one of claims 1 to 11, the outer member having an outer raceway groove on its inner circumferential surface; the inner member having an inner raceway groove on an outer peripheral surface thereof facing the outer raceway groove; a rolling element that is rollably accommodated between the outer raceway groove of the outer member and the inner raceway groove of the inner member.

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