WO2022219782A1

WO2022219782A1 - Sealing device and rolling bearing device

Info

Publication number: WO2022219782A1
Application number: PCT/JP2021/015610
Authority: WO
Inventors: 卓也本庄; 英将原田; 義浩中川; 稔博羽方
Original assignee: 株式会社ジェイテクト
Priority date: 2021-04-15
Filing date: 2021-04-15
Publication date: 2022-10-20
Also published as: JPWO2022219782A1

Abstract

A sealing device according to the present invention is provided between an external member and an internal member and comprises: a slinger having a first cylindrical part that is fixed to the outer circumferential surface of the internal member, a first disc part that extends toward the radial-direction outer side from the end on one axial-direction side of the first cylindrical part, and a second cylindrical part that extends toward the other axial-direction side from the end on the radial-direction outer side of the first disc part; and a seal member having a third cylindrical part that is fixed to the inner circumferential surface of the external member, a second disc part that extends toward the radial-direction inner side from the end on the other axial-direction side of the third cylindrical part, and a seal lip that is provided on the second disc part and is in sliding contact with the slinger. The outer circumferential surface of the second cylindrical part includes a first inclined surface that increases in size toward the one axial-direction side. The inner circumferential surface of the third cylindrical part includes a second inclined surface that faces the first inclined surface in the radial direction and increases in size toward the one axial-direction side. The first inclined surface is formed from a polymer material.

Description

Sealing device and rolling bearing device

The present invention relates to sealing devices and rolling bearing devices.

Conventionally, a sealing device used for a wheel bearing device is known (for example, Patent Document 1). A wheel bearing device is a device that supports a wheel of an automobile or the like. A wheel bearing device includes an outer member and an inner member that are concentrically arranged, and a plurality of rolling elements that are arranged between the outer member and the inner member. The sealing device is provided between the outer member and the inner member, and the annular space formed between the outer member and the inner member (that is, the space inside the bearing where the rolling elements are provided). ) to prevent foreign matter such as muddy water from entering.

JP 2020-51597 A

FIG. 6 is a diagram explaining the problem of the present invention. FIG. 6 shows an axial cross-sectional view of a sealing device 90 according to Patent Document 1. As shown in FIG. The sealing device 90 is provided in the wheel bearing device to prevent muddy water or the like from entering the internal space S92 from the external space S91. The sealing device 90 has a slinger 91 provided at the inner end of the inner member 95 and a seal plate 92 provided at the inner end of the outer member 96 .

The slinger 91 includes a slinger fitting portion 91a fitted to the inner member 95, an upright plate portion 91b extending radially outward from the end of the slinger fitting portion 91a, and an axially extending portion extending from the end of the upright plate portion 91b. and a cylindrical portion 91c bent into a cylindrical shape. The seal plate 92 includes a seal plate fitting portion 92a fitted to the outer member 96, a lip support portion 92b extending radially inward from the end of the seal plate fitting portion 92a, and a lip support portion 92b. It has an axial lip 92c, a radial lip 92d and a grease lip 92e. An outer peripheral surface 93 of the cylindrical portion 91c and an inner peripheral surface 94 of the seal plate fitting portion 92a are surfaces parallel to the axial direction.

A space S93 for temporarily receiving muddy water or the like is formed in the sealing device 90 . By relatively increasing the radial distance from the base to the tip of the axial lip 92c, muddy water or the like entering the space S93 is prevented from reaching the tip of the axial lip 92c. In addition, the radial lip 92d and the grease lip 92e contact or come close to the slinger 91 through the oil film, thereby preventing muddy water or the like in the space S93 from entering the internal space S92.

In the conventional sealing device 90 shown in FIG. 6, it is assumed that muddy water or the like enters the space S93 from the external space S91, and the plurality of lips 92c to 92e suppress the muddy water or the like in the space S93 from entering the internal space S92. ing. However, when the amount of muddy water or the like entering the space S93 increases, it becomes difficult to completely prevent the muddy water or the like from entering the internal space S92. Further, when the amount of muddy water or the like entering the space S93 increases, for example, the mud gets caught between the lips 92c to 92e and the slinger 91, causing the lips 92c to 92e to wear. When the sealing device 90 deteriorates due to the intrusion of muddy water or the like into the space S93, the intrusion of the muddy water or the like into the internal space S92 cannot be sufficiently suppressed.

Here, in order to suppress the intrusion of muddy water or the like into the space S93, the gap between the outer peripheral surface 93 and the inner peripheral surface 94 may be made narrower, or the gap between the outer peripheral surface 93 and the inner peripheral surface 94 may be made uneven ( labyrinth-like). However, if the gap between the outer peripheral surface 93 and the inner peripheral surface 94 is narrowed, foreign matter such as mud may get caught between the outer peripheral surface 93 and the inner peripheral surface 94 and damage the sealing device 90 .

In addition, even if the above structure is adopted, it is not possible to completely prevent muddy water from entering the space S93, and the muddy water will enter the space S93. If the structure described above is adopted, it becomes difficult to expel muddy water or the like that has once entered the space S93 into the external space S91, and there is a risk that the muddy water or the like will accumulate in the space S93 over time. Thus, the conventional sealing device 90 has a problem that the more it is attempted to suppress the intrusion of muddy water or the like into the space S93, the more difficult it becomes to discharge the muddy water or the like from the space S93. The deterioration of the sealing device 90 due to

Therefore, an object of the present disclosure is to provide a sealing device and a rolling bearing device capable of suppressing deterioration due to intrusion of muddy water or the like.

A sealing device of the present invention is provided between an outer member having an outer ring raceway on its inner peripheral surface and an inner member having an inner ring raceway on its outer peripheral surface and rotating relative to the outer member. A sealing device, comprising: a first cylindrical portion fixed to the outer peripheral surface of the inner member; a first disc portion extending radially outward from one axial end of the first cylindrical portion; a second cylindrical portion extending from the radially outer end of the first disk portion toward the other axial side; a third cylindrical portion fixed to the inner peripheral surface of the outer member; a seal member having a second disk portion extending radially inward from the other end portion in the axial direction of the third cylindrical portion; and a seal lip provided on the second disk portion and in sliding contact with the slinger. , wherein the outer peripheral surface of the second cylindrical portion includes a first inclined surface whose diameter increases toward one side in the axial direction, and the inner peripheral surface of the third cylindrical portion is radially aligned with the first inclined surface The sealing device includes a second slanted surface opposed to and whose diameter increases toward one side in the axial direction, the first slanted surface being made of a polymeric material.

According to the disclosed invention, deterioration of the sealing device due to intrusion of muddy water or the like can be suppressed.

1 is a cross-sectional view showing a rolling bearing device according to an embodiment; FIG. It is a sectional view showing a sealing device concerning an embodiment. 3 is an enlarged view of a part of the sealing device of FIG. 2; FIG. It is the figure which expanded a part of sealing device which concerns on a modification. It is the figure which expanded a part of sealing device which concerns on a modification. It is a figure explaining the subject of this invention.

[Description of the embodiment of the present invention]
Embodiments of the present invention include at least the following as their gists.

(1) A sealing device of the present invention is provided between an outer member having an outer ring raceway on its inner peripheral surface and an inner member having an inner ring raceway on its outer peripheral surface and rotating relative to the outer member. a first cylindrical portion fixed to the outer peripheral surface of the inner member; and a first circular plate extending radially outward from one axial end of the first cylindrical portion. a second cylindrical portion extending from the radially outer end of the first disk portion toward the other axial side; and a third cylindrical portion fixed to the inner peripheral surface of the outer member. a second disk portion extending radially inward from the other axial end of the third cylindrical portion; and a seal lip provided on the second disk portion and in sliding contact with the slinger. a seal member, wherein the outer peripheral surface of the second cylindrical portion includes a first inclined surface that expands toward one side in the axial direction, and the inner peripheral surface of the third cylindrical portion includes the first inclined surface. and a second slanted surface radially opposed to and expanding toward one axial side, the first slanted surface being made of a polymeric material.

Since both the first inclined surface and the second inclined surface increase in diameter toward the one axial side, the gap between the first inclined surface and the second inclined surface is inclined radially outward toward the one axial side. . Therefore, when the inner member rotates relative to the outer member, the centrifugal force causes the fluid to flow toward the outer space of the sealing device. As a result, it is possible to more preferably discharge muddy water or the like that has once entered the inside while suppressing muddy water or the like from entering the inside of the sealing device. In addition, since the first inclined surface is made of a polymeric material, it has higher water repellency than metal. Therefore, it is possible to further suppress the intrusion of muddy water and the like, and more preferably discharge the muddy water and the like that have once entered the interior. As a result, deterioration of the sealing device due to intrusion of muddy water or the like can be suppressed.

(2) Preferably, the inner peripheral surface of the second cylindrical portion includes a parallel surface parallel to the axial direction, or a third inclined surface whose diameter decreases toward one side in the axial direction.

With this configuration, when the inner member rotates relative to the outer member, muddy water or the like collected on the inner peripheral surface of the second cylindrical portion moves toward the first disc portion. It is possible to suppress the action of force. Therefore, intrusion of muddy water or the like can be further suppressed.

(3) Preferably, the first inclination angle with respect to the axial direction of the first inclined surface is larger than the second inclination angle with respect to the axial direction of the second inclined surface.

With this configuration, when the inner member rotates relative to the outer member, the fluid flows toward the outer space at the opening on the outer space side formed by the first inclined surface and the second inclined surface. flow can be made faster. As a result, muddy water or the like can be vigorously discharged from the opening to the external space, so clogging of the opening with foreign matter can be suppressed, and deterioration in discharge performance of the sealing device for muddy water or the like due to long-term use can be suppressed. can. In addition, since the opening on the outside space side is narrow, it is possible to further suppress the intrusion of muddy water and the like.

(4) Preferably, the end portion of the third cylindrical portion on one side in the axial direction is aligned with an imaginary line extending in the one side in the axial direction from a center line in the radial direction of the first inclined surface and the second inclined surface. do not cross.

With this configuration, it is possible to prevent the end of the third cylindrical portion from blocking the flow of fluid toward the external space. As a result, it is possible to improve the discharge performance of muddy water and the like in the sealing device.

(5) The rolling bearing device of the present invention comprises the outer member, the inner member, a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway, and (1) to ( 4) A rolling bearing device comprising:

Since the above-described rolling bearing device is provided with any one of the above-described sealing devices (1) to (4), deterioration of the sealing device due to intrusion of muddy water or the like can be suppressed.

[Details of the embodiment of the present invention]
Hereinafter, details of embodiments of the present invention will be described with reference to the drawings.

[Overall Configuration of Rolling Bearing Device]
FIG. 1 is a cross-sectional view showing a rolling bearing device 10 according to an embodiment. The rolling bearing device 10 is a wheel bearing device for supporting wheels of a vehicle such as an automobile, and is also called a hub unit. The rolling bearing device 10 is attached to a suspension system (also referred to as a knuckle) provided in a vehicle and rotatably supports a wheel. The rolling bearing device 10 includes an outer member 11, an inner member 12, a plurality of rolling elements 13, a retainer 14, and two

sealing devices

15,16.

Here, the direction parallel to the center line C1 of the rolling bearing device 10 is called "axial direction". When the rolling bearing device 10 is attached to the suspension system, the central side of the vehicle body (also referred to as the vehicle inner side, which corresponds to the right side in FIG. 1) will be referred to as "one axial side" and the wheel side (vehicle outer side). corresponding to the left side of FIG. 1) is referred to as the "other side in the axial direction". A direction orthogonal to the axial direction is called a "radial direction". The side closer to the center line C1 is referred to as "radial inner side", and the side away from the center line C1 is referred to as "radial outer side".

The outer member 11 is also called an outer ring member, and is a substantially cylindrical member provided with its axis aligned with the center line C1. The outer member 11 has two outer ring raceways 11b1 and 11b2 on the inner peripheral surface 11a.

The inner member 12 is a substantially cylindrical member provided with its axis aligned with the center line C1. The inner member 12 has a hub axle 21 and an inner ring 22 attached to one axial side of the hub axle 21 . Hub axle 21 is also referred to as an inner axle. A flange 21a for fixing a wheel is formed on the other side of the hub axle 21 in the axial direction. The inner member 12 has two inner ring raceways 12b1 and 12b2 on the outer peripheral surface 12a. The inner ring raceway 12 b 1 on one side in the axial direction is formed on the outer peripheral surface of the inner ring 22 . The inner ring raceway 12 b 2 on the other side in the axial direction is formed on the outer peripheral surface of the hub axle 21 .

A plurality of rolling elements 13 are provided in two rows in the axial direction. A plurality of rolling elements 13 provided between the outer ring raceway 11b1 and the inner ring raceway 12b1 form a row on one side in the axial direction, and a plurality of rolling elements 13 provided between the outer ring raceway 11b2 and the inner ring raceway 12b2. A moving body 13 constitutes a row on the other side in the axial direction. The cage 14 holds a plurality of rolling elements 13 . The plurality of rolling elements 13 roll between the outer ring raceways 11b1 and 11b2 and the inner ring raceways 12b1 and 12b2, so that the inner member 12 rotates relative to the outer member 11 around the center line C1. In this embodiment, the outer member 11 is a fixed member that is fixed to the suspension system, and the inner member 12 is a rotating member that rotates with respect to the suspension system (and vehicle body).

The sealing

devices

15 and 16 are provided between the outer member 11 and the inner member 12 . The sealing device 15 is a vehicle inner side sealing device provided on one side in the axial direction relative to the outer ring raceway 11b1 and the inner ring raceway 12b1. The sealing device 16 is a vehicle outer side sealing device provided on the other side in the axial direction relative to the outer ring raceway 11b2 and the inner ring raceway 12b2. The sealing

devices

15 and 16 are devices for preventing muddy water or the like from entering the inner space S2 formed between the outer member 11 and the inner member 12 from the outer space S1 of the rolling bearing device 10 . The internal space S<b>2 is a space inside the rolling bearing device 10 surrounded by the inner peripheral surface 11 a of the outer member 11 , the outer peripheral surface 12 a of the inner member 12 , the sealing device 15 and the sealing device 16 .

[Structure of sealing device]
FIG. 2 is a cross-sectional view showing the sealing device 15 on one axial side (vehicle inner side). One axial side of the sealing device 15 (the right side in FIG. 2) is the external space S1, and the other axial side of the sealing device 15 (the left side in FIG. 2) is the internal space S2. The sealing device 15 has a slinger 30 and a sealing member 40 .

The slinger 30 has a first cylindrical portion 31, a first disk portion 32, and a second cylindrical portion 33 in terms of shape. The slinger 30 has a metal member 30a made of metal and a polymer member 30b made of a polymer material. The metal member 30a is a member for increasing the strength of the slinger 30, and is made of steel such as stainless steel.

The polymer member 30b is a member containing a polymer material, and includes, for example, nitrile rubber (NBR), fluororubber such as vinylidene fluoride rubber (FKM), and polyamide (PA) such as nylon. The polymer member 30b has the function of enhancing the adhesion of the slinger 30 and the drainage performance, which will be described later. The polymer member 30b is a member having higher elasticity than the metal member 30a.

Also, the contact angle of the polymer member 30b with water is larger than the contact angle of the metal member 30a with water. For example, when the metal member 30a is made of stainless steel, the contact angle of the metal member 30a with water is about 70 degrees. In this case, the polymer member 30b is made of a hydrophobic material having a contact angle with water of greater than 70 degrees. That is, the polymer member 30b has a property of being less wet with water than the metal member 30a.

The first cylindrical portion 31 is a cylindrical portion fixed to the outer peripheral surface 12a of the inner member 12 (more specifically, the inner ring 22). The first cylindrical portion 31 is fitted to the outer peripheral surface 12a with a predetermined interference. The first cylindrical portion 31 is made of, for example, a metal member 30a, but may include a polymer member 30b.

The first disk portion 32 is a disk-shaped portion that extends radially outward from one axial end of the first cylindrical portion 31 . The first disc portion 32 has a metal portion 32a and a polymer portion 32b covering one axial side of the metal portion 32a. The metal portion 32a is formed by the metal member 30a, and the polymer portion 32b is formed by the polymer member 30b.

The second cylindrical portion 33 is a cylindrical portion extending from the radially outer end portion of the first disc portion 32 to the other side in the axial direction. The second cylindrical portion 33 has a metal portion 33a, a polymer portion 33b covering the radially outer side of the metal portion 33a, and a polymer portion 33c covering the other axial side of the metal portion 33a. The metal portion 33a is formed by the metal member 30a, and the

polymer portions

33b and 33c are formed by the polymer member 30b.

The seal member 40 has a third cylindrical portion 41, a second disc portion 42, and a seal lip 43 in terms of shape. The sealing member 40 has a metal member 40a made of metal and a polymer member 40b made of a polymer material. The metal member 40a is a member for increasing the strength of the sealing member 40, and is made of steel such as mild steel. The polymer member 40b contains the same material as the polymer member 30b, and has the function of enhancing the adhesion of the seal member 40 and the drainage performance described later.

The third cylindrical portion 41 is a cylindrical portion fixed to the inner peripheral surface 11 a of the outer member 11 . The third cylindrical portion 41 is fitted to the inner peripheral surface 11a with a predetermined interference. The third cylindrical portion 41 has a metal portion 41a, a polymer portion 41b covering the radially inner side of the metal portion 41a, and a polymer portion 41c covering one axial end of the metal portion 41a. The metal portion 41a is formed by the metal member 40a, and the

polymer portions

41b and 41c are formed by the polymer member 40b.

The second disk portion 42 is a disk-shaped portion that extends radially inward from the other axial end of the third cylindrical portion 41 . The second disk portion 42 has a metal portion 42a and a polymer portion 42b covering one axial side of the metal portion 42a. The metal portion 42a is formed by the metal member 40a, and the polymer portion 42b is formed by the polymer member 40b.

The seal lip 43 is a portion that is provided on the second disk portion 42 and comes into sliding contact with the slinger 30 . The seal lip 43 has a first lip 43a, a second lip 43b and a third lip 43c. Each of the lips 43a to 43c is formed of the polymer member 40b and extends from the radially inner end of the second disk portion 42 toward the slinger 30 side.

Although each of the lips 43a to 43c is in contact with the slinger 30 in this embodiment, they may face the slinger 30 with a slight gap (for example, 0.5 mm or less). Also, in the present embodiment, the number of lips included in the seal lip 43 is three, but the number of lips is not particularly limited. That is, one of the lips 43a to 43c may be omitted, or a lip may be added in addition to the lips 43a to 43c.

A space formed by the seal lip 43 and the slinger 30 (for example, a space surrounded by the second lip 43b, the third lip 43c, and the first cylindrical portion 31) may be filled with the sealing liquid L1. . The liquid L1 is, for example, base oil of grease supplied to the internal space S2 to lubricate the rolling elements 13 .

A space S3 and a gap S4 are formed inside the sealing device 15 . The space S3 is a space surrounded by the first disc portion 32, the second cylindrical portion 33, the second disc portion 42, and the first lip 43a. A gap S<b>4 is a gap between the outer peripheral surface 34 of the second cylindrical portion 33 and the inner peripheral surface 44 of the third cylindrical portion 41 . The gap S4 includes an opening AP1 communicating with the external space S1 on one side in the axial direction and an opening AP2 communicating with the space S3 on the other side in the axial direction.

FIG. 3 is an enlarged view of part of the sealing device 15 of FIG. FIG. 3 shows an enlarged area including the gap S4. The outer peripheral surface 34 of the second cylindrical portion 33 includes a first inclined surface 34a whose diameter increases toward one side in the axial direction. The first inclined surface 34a is formed by a polymer portion 33b (that is, a hydrophobic material having a contact angle with water greater than 80 degrees). A first inclination angle θ11 of the first inclined surface 34a with respect to the axial direction is larger than 0 degrees and smaller than 5 degrees (0°<θ11<5°). The inner peripheral surface 35 of the second cylindrical portion 33 includes a parallel surface 35a parallel to the axial direction.

The inner peripheral surface 44 of the third cylindrical portion 41 includes a second inclined surface 44a whose diameter increases toward one side in the axial direction. The second inclined surface 44a is formed by a polymer portion 41b (that is, a hydrophobic material having a contact angle with water greater than 80 degrees). A second inclination angle θ12 of the second inclined surface 44a with respect to the axial direction is larger than 0 degrees and smaller than 5 degrees (0°<θ12<5°). Also, the second tilt angle θ12 is equal to the first tilt angle θ11 (θ12=θ11). Therefore, the second inclined surface 44a faces the first inclined surface 34a in parallel in the radial direction.

The gap inclination angle θ13 with respect to the axial direction of the center line C2 in the radial direction between the first inclined surface 34a and the second inclined surface 44a is the average value of the first inclined angle θ11 and the second inclined angle θ12 (θ13=(θ11+θ12) /2), and in this embodiment, these angles θ11 to θ13 are all equal (θ13=θ12=θ11). Therefore, the gap inclination angle θ13 is larger than 0 degree and smaller than 5 degrees, and the gap S4 formed between the first inclined surface 34a and the second inclined surface 44a increases toward one side in the axial direction. It becomes a gap inclined radially outward.

The distance H1 between the first inclined surface 34a and the second inclined surface 44a (the distance in the direction orthogonal to the center line C2, also referred to as the width of the gap S4) is, for example, 0.3 mm or more and 0.5 mm or less. (0.3 mm≦H1≦0.5 mm). In addition, the end portion 45 on one side in the axial direction of the third cylindrical portion 41 does not intersect the imaginary line VL1 extending from the center line C2 to the one side in the axial direction.

[Action and effect of the sealing device]
The sealing device 15 prevents muddy water or the like from entering from the external space S1 by setting the distance H1 to 0.5 mm or less. For example, it is possible to suppress the intrusion of sand larger than coarse-grained sand (particle size of 0.5 mm or more). On the other hand, if the distance H1 is too narrow, foreign matter (for example, sand) may get caught between the first inclined surface 34a and the second inclined surface 44a and damage the sealing device 15 . Therefore, the distance H1 is set to 0.3 mm or more.

With this configuration, it is difficult to completely prevent muddy water and the like from entering from the external space S1. For example, smaller particle size sand, silt, clay (for example, particle size of 0.2 mm or less) and water can enter the gap S4 from the outer space S1.

Therefore, in the sealing device 15, the clearance S4 is inclined. This makes it easier to discharge muddy water or the like that has once entered the gap S4 and the space S3 from the external space S1 to the external space S1, and prevents the muddy water or the like from accumulating in the space S3, thereby suppressing deterioration of the sealing device 15. can do. This action will be described in detail below.

In the sealing device 15, since both the first inclined surface 34a and the second inclined surface 44a increase in diameter toward one side in the axial direction, the gap S4 formed by the first inclined surface 34a and the second inclined surface 44a The gap is inclined radially outward toward one direction side. That is, the opening AP1 is located radially outside the opening AP2.

Therefore, when the inner member 12 rotates relative to the outer member 11 and the slinger 30 rotates relative to the seal member 40 accordingly, the centrifugal force acting on the area near the opening AP1 is greater than that of the opening AP2. It becomes larger than the centrifugal force applied to the nearby area, and a centrifugal force difference is generated between the opening AP1 and the opening AP2. Due to this centrifugal force difference, a pressure difference is generated between the openings AP1 and AP2, and a fluid flow is generated in the gap S4 from the opening AP2 toward the opening AP1.

Due to this flow, muddy water or the like that has entered the space S3 and the gap S4 is discharged to the external space S1. In order for muddy water or the like to enter the space S3 from the outer space S1 while the slinger 30 is rotating, it is necessary to oppose the flow of the fluid from the opening AP2 toward the opening AP1. intrusion can be suppressed.

Furthermore, in the sealing device 15, both the first inclined surface 34a and the second inclined surface 44a are made of a hydrophobic material (polymer material). With this configuration, muddy water or the like can easily slide on the first inclined surface 34a and the second inclined surface 44a while the slinger 30 is rotating, and the muddy water or the like can be discharged with less force (that is, muddy water, etc. is easily shaken off to the outside). Therefore, it is possible to improve the discharge performance of muddy water and the like in the sealing device 15 .

In addition, since the first inclined surface 34a and the second inclined surface 44a are made of a hydrophobic material, it is difficult for water to spread over the first inclined surface 34a and the second inclined surface 44a. Therefore, while the slinger 30 is stopped, muddy water or the like can be prevented from entering the space S3 while wetting and spreading on the first inclined surface 34a and the second inclined surface 44a.

In particular, the portion of the first inclined surface 34a above the center line C1 in the vertical direction (the portion shown in FIG. 3) is such that muddy water or the like moves from the opening AP1 to the opening AP2 due to gravity while the slinger 30 is stopped. Easy to drip. Therefore, by forming at least the first inclined surface 34a of the first inclined surface 34a and the second inclined surface 44a with a hydrophobic material, it is possible to suppress the intrusion of muddy water or the like while the slinger 30 is stopped.

In addition, the inner peripheral surface 35 of the second cylindrical portion 33 is a parallel surface 35a parallel to the axial direction. That is, the diameter of the first inclined surface 34a increases toward one side in the axial direction, but the diameter of the inner peripheral surface 35 does not increase toward the one side in the axial direction. During rotation of the slinger 30, muddy water or the like in the space S3 is collected near the inner peripheral surface 35 by centrifugal force.

Here, if the inner peripheral surface 35 expands in diameter toward one side in the axial direction, muddy water or the like collected near the inner peripheral surface 35 tends to move toward the first disk portion 32 side. After the rotation of the slinger 30 stops, the muddy water or the like that has moved toward the first disk portion 32 may move along the first disk portion 32 and enter radially inward of the first lip 43a. be.

Since the inner peripheral surface 35 of the present embodiment is a parallel surface 35a that is parallel to the axial direction, a force that moves muddy water or the like toward the first disk portion 32 during rotation of the slinger 30 does not act. Therefore, it is possible to further suppress the intrusion of muddy water or the like into the internal space S2. Further, as described above, during the rotation of the slinger 30, the fluid flows from the opening AP2 toward the opening AP1. Therefore, the muddy water or the like collected on the inner peripheral surface 35 is sucked into the gap S4 from the opening AP2, and the external space is discharged. It becomes easier to be discharged to S1.

Further, the end portion 45 on one side in the axial direction of the third cylindrical portion 41 does not intersect the imaginary line VL1 extending from the center line C2 in the one side in the axial direction. With this configuration, it is possible to prevent the end 45 from blocking the flow of fluid from the opening AP2 toward the opening AP1. As a result, the flow rate of the fluid can be increased, and the discharge of muddy water or the like from the sealing device 15 can be improved.

[Modification]
Modifications of the embodiment will be described below. In the modified example, the same reference numerals are given to the same configurations as in the embodiment, and the description thereof is omitted.

[Modified example of the outer peripheral surface of the second cylindrical part]
FIG. 4 is an enlarged view of a part of a sealing device 15a according to a modification. The sealing device 15a differs from the sealing device 15 according to the above-described embodiment in the shape of the outer peripheral surface 34, and the other points are common.

The outer peripheral surface 34 of the second cylindrical portion 33 includes a first inclined surface 34b whose diameter increases toward one side in the axial direction. A first inclination angle θ21 of the first inclined surface 34b with respect to the axial direction is larger than 0 degrees and smaller than 5 degrees (0°<θ21<5°). Furthermore, the first inclination angle θ21 is larger than the second inclination angle θ12 of the second inclined surface 44a of the third cylindrical portion 41 (θ21>θ12). That is, the first inclined surface 34b of the modified example is inclined more than the first inclined surface 34a of the above embodiment.

Therefore, the first inclined surface 34b and the second inclined surface 44a face each other in the radial direction so that the distance between them decreases toward the one side in the axial direction. That is, the gap S4a formed between the first inclined surface 34b and the second inclined surface 44a has a tapered shape (substantially conical shape) from the opening AP2 toward the opening AP1. The distance between the first inclined surface 34b and the second inclined surface 44a is, for example, 0.3 mm at the opening AP1, and is, for example, 0.5 mm at the opening AP2.

A clearance inclination angle θ23 with respect to the axial direction of the center line C3 in the radial direction between the first inclined surface 34b and the second inclined surface 44a is the average value of the first inclined angle θ21 and the second inclined angle θ12 (θ23=(θ21+θ12 )/2). In this modified example, the second tilt angle θ12 is greater than 0 degrees, and the first tilt angle θ21 is greater than the second tilt angle θ12 (θ21>θ12>0°). a large value. Therefore, the gap S4a formed between the first inclined surface 34b and the second inclined surface 44a becomes a gap inclined radially outward toward the one side in the axial direction. An end portion 45 on one side in the axial direction of the third cylindrical portion 41 does not intersect the imaginary line VL2 extending from the center line C3 to the one side in the axial direction.

Since the sealing device 15a is formed with a gap S4a that is inclined radially outward toward one axial side, the fluid flows from the opening AP2 to the opening AP1 during rotation of the slinger 30, as in the above-described embodiment. can produce a flow of Furthermore, in the case of the sealing device 15a, since the opening AP1 is narrower than the opening AP2, the flow of the fluid from the opening AP2 toward the opening AP1 can be made faster near the opening AP1 while the slinger 30 is rotating. etc. can be vigorously discharged from the opening AP1 to the external space S1.

As a result, relatively heavy foreign matter (foreign matter that is difficult to move) can be more reliably discharged to the external space S1. In addition, by making the fluid flow faster near the opening AP1, it is possible to prevent relatively large foreign matter from clogging the gap S4a, thereby preventing the deterioration of the muddy water discharge performance of the sealing device 15a due to long-term use. can be suppressed. In addition, since the opening AP1 is formed narrower, it is possible to prevent muddy water or the like from entering the gap S4a through the opening AP1.

Further, the end portion 45 on one side in the axial direction of the third cylindrical portion 41 does not intersect the imaginary line VL2 extending from the center line C3 to the one side in the axial direction. With this configuration, it is possible to prevent the end 45 from blocking the flow of fluid from the opening AP2 toward the opening AP1. As a result, the flow rate of the fluid can be increased, and the discharge of muddy water or the like from the sealing device 15 can be improved.

[Modified Example of the Inner Peripheral Surface of the Second Cylindrical Part]
FIG. 5 is an enlarged view of a part of a sealing device 15b according to a modification. The sealing device 15b differs from the sealing device 15 according to the above embodiment in the shape of the inner peripheral surface 35, and the other points are common.

The inner peripheral surface 35 of the second cylindrical portion 33 includes a third inclined surface 35b whose diameter decreases toward one side in the axial direction. A third inclination angle θ14 of the third inclined surface 35b with respect to the axial direction is, for example, larger than 0 degrees and smaller than 5 degrees (0°<θ14<5°). That is, the third inclined surface 35b is inclined to the opposite side (the other side in the axial direction) of the first inclined surface 34a and the second inclined surface 44a.

During rotation of the slinger 30, muddy water and the like in the space S3 are collected near the inner peripheral surface 35 due to centrifugal force. Since the inner peripheral surface 35 of this modified example is the third inclined surface 35b whose diameter decreases toward one side in the axial direction, it moves toward the second disk portion 42 when muddy water or the like is present during rotation of the slinger 30. force acts. Therefore, muddy water or the like collected near the inner peripheral surface 35 is guided to the opening AP2 along the third inclined surface 35b. As a result, the muddy water or the like in the space S3 is easily discharged by the external space S1.

[Other Modifications]
The sealing

devices

15, 15a, and 15b are provided on one axial side (vehicle inner side) of the rolling bearing device 10 (see FIG. 1). However, each of the configurations described above may be applied to the sealing device 16 on the other axial side (vehicle outer side).

The rolling bearing device 10 described above is a wheel bearing device for supporting wheels of a vehicle such as an automobile. However, the rolling bearing device 10 may be applied to devices other than wheel bearing devices. For example, it may be applied to a rotating body bearing device for supporting rotating bodies such as propellers, turbines, and spinning wheels.

[Supplement]
It should be noted that at least some of the embodiments and various modifications described above may be combined arbitrarily with each other. In addition, the embodiments and modifications disclosed this time are illustrative in all respects and are not restrictive. The scope of the present disclosure is indicated by the claims, and is intended to include all changes within the meaning and range of equivalents to the claims.

10 rolling bearing device 11 outer member 11a inner peripheral surface 11b1 outer ring raceway 11b2 outer ring raceway 12 inner member 12a outer peripheral surface 12b1 inner ring raceway 12b2 inner ring raceway 13 rolling element 14 retainer 15 sealing device 15a sealing device 15b sealing device 16 sealing device 21 hub axle 21a flange 22 inner ring 30 slinger 30a metal member 30b polymer member 31 first cylindrical portion 32 first disk portion 32a metal portion 32b polymer portion 33 second cylindrical portion 33a metal portion 33b polymer portion 33c polymer portion 34 Outer peripheral surface 34a First inclined surface 34b First inclined surface 35 Inner peripheral surface 35a Parallel surface 35b Third inclined surface 40 Seal member 40a Metal member 40b Polymer member 41 Third cylindrical portion 41a Metal portion 41b Polymer portion 41c Polymer portion 42 Second disk portion 42a Metal portion 42b Polymer portion 43 Seal lip 43a First lip 43b Second lip 43c Third lip 44 Inner peripheral surface 44a Second inclined surface 45 End portion 90 Sealing device 91 Slinger 91a Slinger fitting portion 91b vertical plate portion 91c cylindrical portion 92 seal plate 92a seal plate fitting portion 92b lip support portion 92c axial lip 92d radial lip 92e grease lip 93 outer peripheral surface 94 inner peripheral surface 95 inner member 96 outer member C1 center line C2 center line C3 center line VL1 virtual line VL2 virtual line S1 outer space S2 inner space S3 space S4 gap S4a gap S91 outer space S92 inner space S93 space L1 liquid AP1 opening AP2 opening θ11 first tilt angle θ12 second tilt angle θ13 gap tilt angle θ14 Third tilt angle θ21 First tilt angle θ23 Gap tilt angle H1 Distance

Claims

A sealing device provided between an outer member having an outer ring raceway on its inner peripheral surface and an inner member having an inner ring raceway on its outer peripheral surface and rotating relative to the outer member,
a first cylindrical portion fixed to the outer peripheral surface of the inner member; a first disc portion extending radially outward from one axial end of the first cylindrical portion; and the first disc portion. a second cylindrical portion extending axially from the radially outer end of the slinger;
a third cylindrical portion fixed to the inner peripheral surface of the outer member; a second disc portion extending radially inward from the other axial end of the third cylindrical portion; and the second disc a seal member having a seal lip provided on the portion and slidably contacting the slinger;
with
The outer peripheral surface of the second cylindrical portion includes a first inclined surface whose diameter increases toward one side in the axial direction,
The inner peripheral surface of the third cylindrical portion includes a second inclined surface radially facing the first inclined surface and increasing in diameter toward one side in the axial direction,
The sealing device, wherein the first inclined surface is made of a polymeric material.
The inner peripheral surface of the second cylindrical portion includes a parallel surface parallel to the axial direction, or a third inclined surface that decreases in diameter toward one side in the axial direction,
A sealing device according to claim 1 .
A first inclination angle with respect to the axial direction of the first inclined surface is greater than a second inclination angle with respect to the axial direction of the second inclined surface,
The sealing device according to claim 1 or 2.
The end of the third cylindrical portion on one side in the axial direction does not intersect an imaginary line extending to the one side in the axial direction from the center line between the first inclined surface and the second inclined surface.
The sealing device according to any one of claims 1 to 3.
the outer member;
the inner member;
a plurality of rolling elements provided between the outer ring raceway and the inner ring raceway;
A sealing device according to any one of claims 1 to 4;
A rolling bearing device.