Seal ring and needle bearing

Abstract

The utility model relates to the technical field of bearing sealing, and discloses a sealing ring and a needle bearing. The sealing ring comprises a main body part and a first convex part, the first convex part is convexly arranged on at least one side surface of the main body part in the axial direction of the sealing ring, and the first convex part is used for being in contact with a needle roller retainer of the needle roller bearing. In other words, the sealing ring is in contact with the needle roller retainer through the first convex part, the contact area between the first convex part and the needle roller retainer is small, and the friction torque between the sealing ring and the needle roller retainer can be reduced. Particularly, under the low-temperature working condition, the friction torque between the sealing ring and the needle roller retainer is small, and the starting torque can be prevented from exceeding the threshold value allowed by the system as far as possible.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of bearing sealing, in particular to a sealing ring and a needle bearing. BACKGROUND

[0002] Rolling needle bearings are applied in electric vacuum pumps. The rolling needle bearings are usually provided with a sealing ring. The sealing ring is mainly used to prevent lubricating oil from leaking out of the rolling needle bearings. However, the rolling needle cage of the rolling needle bearing is prone to contact with the sealing ring, which causes excessive friction torque between the rolling needle cage and the sealing ring. In a low-temperature working condition, the excessive friction torque between the rolling needle cage and the sealing ring may cause the starting torque to exceed the threshold allowed by the system, thereby causing a fault problem. CONTENT OF THE UTILITY MODEL

[0003] The present application provides a sealing ring and a rolling needle bearing, which can reduce the friction torque between the sealing ring and the rolling needle cage.

[0004] The present application provides a sealing ring. The sealing ring is applied to a rolling needle bearing. The sealing ring comprises a main body part and a first protruding part. The main body part is annularly arranged. The first protruding part is protruded on at least one side surface of the main body part in the axial direction of the sealing ring, and the first protruding part is used to contact with the rolling needle cage of the rolling needle bearing.

[0005] In an embodiment of the present application, the sealing ring further has a reference plane perpendicular to the axial direction thereof; wherein the first protruding part has a smaller normal projection area on the reference plane than the main body part.

[0006] In an embodiment of the present application, the sealing ring further has a radial direction perpendicular to the axial direction thereof, and the first protruding part extends along the radial direction.

[0007] In an embodiment of the present application, the number of the first protruding parts is plural, each first protruding part is distributed along the circumferential direction of the main body part, and each first protruding part extends along the radial direction.

[0008] In an embodiment of the present application, the first protruding part extends along the circumferential direction of the main body part.

[0009] In an embodiment of the present application, the sealing ring further has a radial direction perpendicular to the axial direction thereof, and the number of the first protruding parts is plural, each first protruding part is distributed along the radial direction of the main body part.

[0010] In an embodiment of the present application, the two side surfaces of the main body part in the axial direction of the sealing ring are both provided with the first protruding part.

[0011] In an embodiment of the present application, the sealing ring further comprises a sealing lip connected to the inner side of the main body, and a plurality of second protrusions, each protruding from the surface of the sealing lip away from the main body, each second protrusion is spaced apart along the axial direction of the sealing ring, and each second protrusion extends along the circumferential direction of the main body, the second protrusion is configured to contact the shaft.

[0012] Correspondingly, the present application also provides a needle bearing, comprising an outer ring provided with a raceway extending along the circumferential direction thereof on the inner side thereof, a needle cage movably arranged in the raceway, and a plurality of needles arranged on the needle cage, and a sealing ring as described in the above embodiments arranged between the outer ring and the needle cage in the axial direction of the needle bearing.

[0013] In an embodiment of the present application, the sealing ring comprises a main body and a sealing lip connected to the inner side of the main body, and a first protrusion protruding from each of the two side surfaces of the main body in the axial direction of the sealing ring, the needle cage is provided with the sealing ring on each side in the axial direction of the needle bearing, and the shaft is configured to be inserted into the needle bearing along a predetermined insertion direction, and the sealing lip of each sealing ring extends obliquely along the predetermined insertion direction and away from the main body connected thereto.

[0014] The present application has the following beneficial effects: Different from the prior art, the present application provides a sealing ring and a needle bearing. The sealing ring comprises a main body and a first protrusion protruding from at least one side surface of the main body in the axial direction of the sealing ring, and the first protrusion is configured to contact the needle cage of the needle bearing. In other words, the sealing ring of the present application contacts the needle cage through the first protrusion, the contact area between the first protrusion and the needle cage is small, which can reduce the friction torque between the sealing ring and the needle cage. Especially in low temperature working conditions, the friction torque between the sealing ring and the needle cage is small, which can avoid the starting torque exceeding the threshold allowed by the system as much as possible. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0016] Figure 1 is a structural schematic diagram of an embodiment of the needle bearing of the present application;

[0017] Figure 2 is a structural schematic diagram of an embodiment of the sealing ring of the present application;

[0018] Figure 3 is a partial structural schematic diagram of an embodiment of the sealing ring of the present application;

[0019] Figure 4 is a structural schematic view of another embodiment of the needle bearing of the present application;

[0020] Figure 5 is a structural schematic view of another embodiment of the sealing ring of the present application.

[0021] Explanation of reference signs:

[0022] 10 needle bearing; 11 outer ring; 111 raceway; 12 needle cage; 13 needle; 20 sealing ring; 21 main body part; 22 first protruding part; 23 sealing lip; 24 second protruding part; 30 shaft. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application. In the present application, unless otherwise specified and limited, the terms such as "connected", "connected", "stacked" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0024] In the present application, unless otherwise explicitly specified and limited, the terms "connected", "connected", "stacked" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0025] The present application provides a sealing ring and a needle bearing, which are described in detail below. It should be noted that the description order of the following embodiments is not limited as the preferred order of the embodiments of the present application. In the following embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0026] To solve the technical problem of large friction torque between the sealing ring and the needle cage in the prior art, an embodiment of the present application provides a sealing ring. The sealing ring is applied to a needle bearing. The sealing ring comprises a main body part and a first protruding part. The main body part is annularly arranged. The first protruding part is protruded on at least one side surface of the main body part in the axial direction of the sealing ring, and the first protruding part is used to contact the needle cage of the needle bearing. Details are described below.

[0027] Please refer to Figure 1 , Figure 1 is a structural schematic diagram of an embodiment of the needle bearing of the present application. Figure 1 It is shown from the longitudinal sectional view along the axial direction of the needle bearing.

[0028] In an embodiment, the needle bearing 10 comprises an outer ring 11, which is annularly arranged, and the inner side of the outer ring 11 is provided with a raceway 111 extending along the circumferential direction thereof. The needle bearing 10 further comprises a needle cage 12, which is movably arranged in the raceway 111, and the needle cage 12 is provided with a plurality of needles 13. The needle bearing 10 further comprises a sealing ring 20, which is arranged between the outer ring 11 and the needle cage 12 in the axial direction of the needle bearing 10. When the shaft 30 is inserted into the needle bearing 10, the sealing ring 20 is used to seal the gap between the outer ring 11 and the shaft 30, so as to prevent the lubricating oil from leaking out of the needle bearing 10.

[0029] The sealing ring 20 of an embodiment of the present application is described below.

[0030] Please refer to Figure 2 and Figure 3 , Figure 2 is a structural schematic diagram of an embodiment of the sealing ring of the present application, Figure 3 is a partial structural schematic diagram of an embodiment of the sealing ring of the present application. Figure 2 It is shown from the longitudinal sectional view along the axial direction of the sealing ring, Figure 2 and Figure 3 both show the partial structure of the sealing ring.

[0031] In an embodiment, the sealing ring 20 is applied to the needle bearing 10, and the mounting manner of the sealing ring 20 in the needle bearing 10 has been described in detail above, and will not be described here. Specifically, the sealing ring 20 comprises a main body part 21 and a first protruding part 22. The main body part 21 is annularly arranged. When the sealing ring 20 is mounted in the needle bearing 10, the main body part 21 extends along the circumferential direction of the outer ring 11. The first protruding part 22 is protruded on at least one side surface of the main body part 21 in the axial direction of the sealing ring 20 (as shown by the arrow Z in Figure 2 , the same below), and the first protruding part 22 is used to contact the needle cage 12 of the needle bearing 10.

[0032] In this manner, during the use of the needle roller bearing 10, the needle roller cage 12 will contact the sealing ring 20. In this embodiment, when the needle roller cage 12 contacts the sealing ring 20, the sealing ring 20 contacts the needle roller cage 12 through the first protrusion 22, instead of the prior art where the sealing ring 20 contacts the needle roller cage 12 through a flat surface. The contact area between the first protrusion 22 and the needle roller cage 12 is smaller, which can reduce the frictional torque between the sealing ring 20 and the needle roller cage 12. Especially under low-temperature conditions, the frictional torque between the sealing ring 20 and the needle roller cage 12 is smaller, which can minimize the risk of the starting torque exceeding the system's allowable threshold.

[0033] It should be noted that the sealing ring 20 also has a reference plane perpendicular to its axial direction (e.g., Figure 2 (As shown in the mid-plane α, the same below). The orthographic projection area of ​​the first protrusion 22 on the reference plane is smaller than the orthographic projection area of ​​the main body 21 on the reference plane. In other words, compared to the contact between the main body 21 and the needle roller retainer 12, the contact area between the first protrusion 22 and the needle roller retainer 12 is smaller, which can reduce the frictional torque between the sealing ring 20 and the needle roller retainer 12.

[0034] In one embodiment, the sealing ring 20 also has a radial direction perpendicular to its axial direction (e.g., Figure 2 As indicated by the middle arrow R (hereinafter the same), the first protrusion 22 extends radially. Specifically, there are multiple first protrusions 22, which are distributed circumferentially around the main body 21 and extend radially. In this way, through these multiple first protrusions 22, this embodiment can ensure that the needle roller retainer 12 contacts the first protrusions 22 as much as possible rather than the main body 21, thus ensuring a small frictional torque between the sealing ring 20 and the needle roller retainer 12.

[0035] Optionally, the plurality of first protrusions 22 may be evenly spaced along the circumference of the main body 21, which is not limited here.

[0036] In one embodiment, the main body 21 has a first protrusion 22 on both sides of the sealing ring 20 in the axial direction. In this way, when the sealing ring 20 is installed on the needle roller bearing 10, the first protrusion 22 on both sides of the main body 21 can contact the needle roller retainer 12, so there is no need to pay special attention to the orientation of the first protrusion 22 of the sealing ring 20 toward the needle roller retainer 12 during installation, which can improve the ease of installation of the sealing ring 20.

[0037] Of course, in other embodiments of this application, the main body 21 may have a first protrusion 22 protruding on only one side surface of the sealing ring 20 in the axial direction, which is not limited here.

[0038] In one embodiment, the sealing ring 20 further includes a sealing lip 23 and a second protrusion 24. The sealing lip 23 is connected to the inner side of the main body 21, that is, the sealing lip 23 is located in the internal space formed by the main body 21. The second protrusion 24 protrudes from the surface of the sealing lip 23 away from the main body 21, and the second protrusion 24 is used to contact the shaft 30. When the shaft 30 is inserted into the needle roller bearing 10, the shaft 30 is embedded in the internal space formed by the main body 21 of the sealing ring 20. The sealing lip 23 contacts the shaft 30 through the second protrusion 24, which can reduce the contact area between the sealing ring 20 and the shaft 30, thereby reducing the frictional torque between the sealing ring 20 and the shaft 30.

[0039] It should be noted that the sealing lip 23 extends obliquely away from the main body 21. Thus, when the shaft 30 is inserted into the needle roller bearing 10, the sealing lip 23 and the shaft 30 have a large amount of interference, forming a seal. Furthermore, compared to the sealing lip 23 directly contacting the shaft 30, in this embodiment, the sealing lip 23 contacts the shaft 30 through the second protrusion 24, resulting in a smaller contact area between the sealing ring 20 and the shaft 30. This reduces the frictional torque between the sealing ring 20 and the shaft 30. The method in this embodiment where the sealing lip 23 contacts the shaft 30 through the second protrusion 24 provides both a large amount of interference and a small contact area. This ensures good sealing performance between the sealing ring 20 and the shaft 30 while minimizing frictional torque, even when the shaft 30 experiences significant dynamic runout and axial movement.

[0040] Furthermore, there are multiple second protrusions 24, each protruding from the surface of the sealing lip 23 opposite to the main body 21. The second protrusions 24 are spaced apart along the axial direction of the sealing ring 20, and each second protrusion 24 extends circumferentially along the main body 21. Each second protrusion 24 is arranged in a ring shape, so that when the sealing lip 23 contacts the shaft 30 through the second protrusions 24, two adjacent second protrusions 24 can cooperate with the shaft 30 to form a relatively enclosed space. This space can store lubricating oil, thus reducing the risk of lubricating oil being carried out by the shaft 30 and leaking from the needle roller bearing 10.

[0041] In one embodiment, the needle roller retainer 12 is provided with sealing rings 20 on both sides of the needle roller bearing 10 in the axial direction. The shaft 30 is configured along a predetermined insertion direction (e.g., Figure 1 (As indicated by the middle arrow X, the same below) Insert the needle roller bearing 10. The sealing lip 23 of each sealing ring 20 extends obliquely along the preset insertion direction and away from the main body 21 to which it is connected, that is, the sealing lip 23 of each sealing ring 20 extends along the insertion direction of the shaft 30, which can reduce the risk of the sealing lip 23 folding over.

[0042] In the above-mentioned sealing ring 20, the sealing lip 23 is inclined to extend along the preset plug-in direction and away from the body part 21, the body part 21 is provided with the first protrusion 22 on the surface in the axial direction of the sealing ring 20, the body part 21 of the sealing ring 20 is provided with the first protrusion 22 on the surface of the needle cage 12, the sealing ring 20 is in contact with the needle cage 12 through the first protrusion 22, the friction torque between the sealing ring 20 and the needle cage 12 is reduced, and the risk that the starting torque exceeds the threshold value allowed by the system under low-temperature working conditions is avoided.

[0043] The sealing ring 20 of another embodiment of the present application is described below.

[0044] Please refer to Figure 4 and Figure 5 , Figure 4 is a structural schematic diagram of another embodiment of the needle bearing of the present application, Figure 5 is a structural schematic diagram of another embodiment of the sealing ring of the present application. Figure 4 It is a longitudinal sectional view along the axial direction of the needle bearing, Figure 5 It is a longitudinal sectional view along the axial direction of the sealing ring, Figure 5 It shows the local structure of the sealing ring.

[0045] In an embodiment, the sealing ring 20 is applied to the needle bearing 10. The sealing ring 20 comprises a body part 21 and a first protrusion 22. The body part 21 is annularly arranged. When the sealing ring 20 is installed on the needle bearing 10, the body part 21 extends along the circumferential direction of the outer ring 11. The first protrusion 22 is provided on at least one side surface of the body part 21 in the axial direction of the sealing ring 20, and the first protrusion 22 is used to contact the needle cage 12 of the needle bearing 10.

[0046] In the above-mentioned manner, in the use process of the needle bearing 10, the needle cage 12 is in contact with the sealing ring 20. In this embodiment, when the needle cage 12 is in contact with the sealing ring 20, the sealing ring 20 is in contact with the needle cage 12 through the first protrusion 22, instead of the contact between the sealing ring 20 and the needle cage 12 through the flat surface in the prior art. The contact area between the first protrusion 22 and the needle cage 12 is small, which can reduce the friction torque between the sealing ring 20 and the needle cage 12. Especially under low-temperature working conditions, the friction torque between the sealing ring 20 and the needle cage 12 is small, which can avoid the risk that the starting torque exceeds the threshold value allowed by the system as much as possible.

[0047] In an embodiment, the first protrusions 22 extend along the circumference of the main body 21, and specifically, the first protrusions 22 can be annularly arranged. Specifically, the number of the first protrusions 22 is plural, and each of the first protrusions 22 is spaced apart along the radial direction of the sealing ring 20 and arranged on the main body 21. In this way, the plurality of first protrusions 22 can make the needle retainer 12 contact the first protrusions 22 as much as possible instead of contacting the main body 21, so as to ensure that the sealing ring 20 and the needle retainer 12 have a smaller friction torque.

[0048] Optionally, the plurality of first protrusions 22 can be uniformly spaced apart along the radial direction of the sealing ring 20, which is not limited herein.

[0049] In an embodiment, the main body 21 is provided with the first protrusions 22 on both sides in the axial direction of the sealing ring 20. In this way, when the sealing ring 20 is installed on the needle bearing 10, both sides of the main body 21 have the first protrusions 22 that can contact the needle retainer 12, so that the first protrusions 22 of the sealing ring 20 do not need to be specially oriented towards the needle retainer 12 during installation, and the installation convenience of the sealing ring 20 can be improved.

[0050] In an embodiment, the sealing ring 20 further comprises a sealing lip 23 and a second protrusion 24. The sealing lip 23 is connected to the inner side of the main body 21, that is, the sealing lip 23 is located in the internal space surrounded by the main body 21. The second protrusion 24 is protruded from the surface of the sealing lip 23 away from the main body 21, and the second protrusion 24 is used to contact the shaft 30. When the shaft 30 is inserted into the needle bearing 10, the shaft 30 is embedded in the internal space surrounded by the main body 21 of the sealing ring 20, and the sealing lip 23 contacts the shaft 30 through the second protrusion 24, so as to reduce the contact area between the sealing ring 20 and the shaft 30, and thus reduce the friction torque between the sealing ring 20 and the shaft 30.

[0051] It should be noted that the sealing lip 23 extends in a direction away from the main body 21, so that when the shaft 30 is inserted into the needle bearing 10, the sealing lip 23 has a large interference with the shaft 30 to form a seal, and compared with the sealing lip 23 directly contacting the shaft 30, the sealing lip 23 of the present embodiment contacts the shaft 30 through the second protrusion 24, so that the sealing ring 20 and the shaft 30 have a smaller contact area, and thus the friction torque between the sealing ring 20 and the shaft 30 can be reduced. The way that the sealing lip 23 of the present embodiment contacts the shaft 30 through the second protrusion 24 has a large interference and a small contact area, so that in the case that the shaft 30 has a large dynamic runout and axial runout, the sealing ring 20 and the shaft 30 can have good sealing performance and a small friction torque.

[0052] Further, the second protrusions 24 are provided in a plurality, each of the second protrusions 24 is protruded from a surface of the sealing lip 23 away from the main body 21, each of the second protrusions 24 is spaced apart along an axial direction of the sealing ring 20, and each of the second protrusions 24 extends along a circumferential direction of the main body 21. Each of the second protrusions 24 is provided in a ring shape, so that when the sealing lip 23 is in contact with the shaft 30 through the second protrusions 24, two adjacent second protrusions 24 can cooperate with the shaft 30 to form a relatively closed space, which can store lubricating oil, thereby reducing the risk of the lubricating oil being taken out by the shaft 30 and then seeping out of the needle bearing 10.

[0053] In an embodiment, the sealing rings 20 are provided on both sides of the needle retainer 12 in the axial direction of the needle bearing 10. The shaft 30 is configured to be inserted into the needle bearing 10 along a preset insertion direction. The sealing lip 23 of each sealing ring 20 extends obliquely along the preset insertion direction and away from the main body 21 connected thereto, that is, the sealing lip 23 of each sealing ring 20 extends along the insertion direction of the shaft 30, thereby reducing the risk of the sealing lip 23 being folded.

[0054] Based on the fact that the sealing lip 23 of each sealing ring 20 extends obliquely along the preset insertion direction and away from the main body 21 connected thereto, the main body 21 is provided with the first protrusion 22 on the surface on both sides in the axial direction of the sealing ring 20, so that the main body 21 of each sealing ring 20 is provided with the first protrusion 22 on the surface facing the needle retainer 12, and each sealing ring 20 is in contact with the needle retainer 12 through the first protrusion 22, thereby reducing the friction torque between the sealing ring 20 and the needle retainer 12 and avoiding the risk of the starting torque exceeding the threshold value allowed by the system under low-temperature working conditions.

[0055] In summary, the present application provides a sealing ring and a needle bearing. The sealing ring comprises a main body and a first protrusion, the first protrusion is protruded from at least one side surface of the main body in the axial direction of the sealing ring, and the first protrusion is used to contact the needle retainer of the needle bearing. In other words, the sealing ring of the present application is in contact with the needle retainer through the first protrusion, the contact area between the first protrusion and the needle retainer is small, which can reduce the friction torque between the sealing ring and the needle retainer. Especially under low-temperature working conditions, the friction torque between the sealing ring and the needle retainer is small, which can avoid the starting torque exceeding the threshold value allowed by the system as much as possible.

[0056] The sealing ring and the needle bearing provided by the present application are described in detail above, and specific examples are applied to describe the principles and implementation modes of the present application. The above description of the embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed, and the content of the description should not be understood as a limitation of the present application.

Claims

1. A seal ring, characterized by, The sealing ring is applied to a needle bearing, and the sealing ring comprises: a body portion arranged annularly; and a first protrusion protruding from at least one side surface of the body portion in the axial direction of the sealing ring, the first protrusion being configured to contact a needle retainer of the needle bearing.

2. The sealing ring according to claim 1, wherein the sealing ring further has a reference plane perpendicular to the axial direction thereof; wherein the first protrusion has a smaller projected area on the reference plane than the body portion.

3. The sealing ring according to claim 1 or 2, wherein the sealing ring further has a radial direction perpendicular to the axial direction thereof, and the first protrusion extends along the radial direction.

4. The sealing ring according to claim 3, wherein the first protrusion is in a plurality, and each of the first protrusions is spaced apart along a circumferential direction of the body portion and extends along the radial direction.

5. The sealing ring according to claim 1 or 2, wherein the first protrusion extends along a circumferential direction of the body portion.

6. The sealing ring according to claim 5, wherein the sealing ring further has a radial direction perpendicular to the axial direction thereof, and the first protrusion is in a plurality, and each of the first protrusions is spaced apart along the radial direction of the body portion.

7. The sealing ring according to claim 1 or 2, wherein the first protrusion is protruded from both side surfaces of the body portion in the axial direction of the sealing ring.

8. The sealing ring according to claim 1 or 2, wherein the sealing ring further comprises: a sealing lip connected to an inner side of the body portion; and a plurality of second protrusions, each of the second protrusions being protruded from a surface of the sealing lip facing away from the body portion, each of the second protrusions being spaced apart along the axial direction of the sealing ring, and each of the second protrusions extending along a circumferential direction of the body portion, the second protrusion being configured to contact a shaft.

9. A needle bearing, characterized by comprises: an outer ring having an inner side provided with a raceway extending along a circumferential direction thereof; a needle retainer movably arranged in the raceway, the needle retainer being provided with a plurality of needles; and the sealing ring according to any one of claims 1 to 8, the sealing ring being arranged between the outer ring and the needle retainer in the axial direction of the needle bearing.

10. The needle bearing according to claim 9, wherein the sealing ring comprises a body portion and a sealing lip connected to an inner side of the body portion, and the first protrusion is protruded from both side surfaces of the body portion in the axial direction of the sealing ring; the needle retainer is provided with the sealing ring on both sides thereof in the axial direction of the needle bearing; and a shaft is configured to be inserted into the needle bearing along a predetermined insertion direction, and the sealing lip of each of the sealing rings extends obliquely along the predetermined insertion direction and away from the body portion connected thereto.

Images