Sealing assemblies for bearings

Abstract

A sealing assembly for a bearing comprises: a skeleton (31) and a sealing member (32). The skeleton is in a bent angular shape and comprises a first bent portion (311) and a second bent portion (312), wherein the first bent portion abuts against the radial outer surface of the bearing outer ring (22), and the first end of the second bent portion is connected to the first bent portion; the sealing member is annular as a whole and comprises a base (321), a first sealing lip (322) and a second sealing lip (323), wherein the first end of the base is attached to the second end of the second bent portion, the first end of the first sealing lip is attached to the second end of the base and extends from the second end of the base to the axial inner side of the bearing obliquely in the axial direction of the bearing so as to contact the radial outer surface of the inner ring of the bearing in an interference fit, and the second sealing lip extends from the second end of the base to the axial outer side of the bearing obliquely in the axial direction of the bearing to the vicinity of the radial outer surface of the inner ring or at the radial outer surface of the inner ring.

Description

Technical Field

[0001] The present application relates to sealing technology, and in particular to a sealing assembly for a bearing. Background Art

[0002] The cylindrical roller bearings of the subway's axle boxes are sealed with metal sealing covers to prevent external contamination and prevent grease leakage. Figure 1 A partial cross-sectional view showing a sealing cover of the prior art assembled on a bearing. Figure 1 As shown, the bearing 2 includes an inner ring 21 and an outer ring 22. The sealing cover 1 is pressed against the outer ring 22 of the bearing 2 and remains stationary. In order to avoid additional friction torque between the sealing cover 1 and the inner ring 21 of the bearing 2, the sealing cover 1 and the inner ring 21 are clearance-fitted in the radial direction.

[0003] Due to the clearance fit, grease leakage is likely to occur. When the vehicle is cleaned with high-pressure water, splashing water droplets can easily enter the bearing from the gap, and external contaminants can also invade the bearing. In addition, there is only a narrow space in the axial direction to install the sealing lip. Summary of the invention

[0004] An object of the present application is to provide a sealing assembly that can reliably seal a bearing.

[0005] The above-mentioned object is solved by a sealing assembly for a bearing according to the present application. The bearing includes an inner ring and an outer ring, the sealing assembly is annular as a whole and is used to seal the internal space between the inner ring and the outer ring, the sealing assembly includes: a frame, which is in a bent angular shape and includes a first bent portion and a second bent portion, the first bent portion abuts against the radial outer surface of the outer ring, and the first end of the second bent portion is connected to the first bent portion; and a seal, which is annular as a whole and includes a base, a first sealing lip and a second sealing lip, the first end of the base is attached to the second end of the second bent portion opposite to the first end, the first end of the first sealing lip is attached to the second end of the base opposite to the first end of the base, and the first sealing lip extends from the second end of the base to the axial inner side of the bearing obliquely with the axial direction of the bearing to contact with the radial outer surface of the inner ring in an interference fit, and the second sealing lip extends from the second end of the base to the axial outer side of the bearing obliquely with the axial direction of the bearing to the radial outer side of the inner ring or at the radial outer surface of the inner ring.

[0006] According to an embodiment of the present application, the first sealing lip includes a PTFE sheet, and the PTFE sheet is disposed at a second end portion of the first sealing lip opposite to the first end portion of the sealing lip.

[0007] According to an embodiment of the present application, the sealing member is made of rubber, and the first end of the base is attached to the second end of the second bent portion by a vulcanization process.

[0008] According to an embodiment of the present application, the first end of the base is attached to both sides of the second end of the second bent portion in the axial direction.

[0009] According to an embodiment of the present application, the base body extends from the second end portion of the second bent portion toward the axial inner side of the bearing at an angle to the axial direction.

[0010] According to an embodiment of the present application, the second bent portion abuts against the axial end surface of the outer ring.

[0011] According to an embodiment of the present application, a thickness of the first sealing lip is greater than a thickness of the second sealing lip.

[0012] According to an embodiment of the present application, a pump liquid groove is provided on an axially outer side surface of a portion of the base body that is not attached to the second end portion of the second bent portion.

[0013] According to an embodiment of the present application, the pump tank has two to five flat walls, and the angle between each wall and the axial direction is different.

[0014] According to an embodiment of the present application, an angle between the first sealing lip and the axial direction of the bearing is between 15° and 70°, and an angle between the wall and the axial direction is between 10° and 65°.

[0015] Since the first sealing lip is interference fit with the radial outer surface of the inner ring, and the second sealing lip extends to the vicinity of the radial outer surface of the inner ring or at the radial outer surface of the inner ring, the first sealing lip of the sealing assembly of the present application can reliably prevent grease from leaking from the inner space of the bearing, and the second sealing lip can prevent foreign matter from entering the inner space. In addition, the cost of the sealing assembly of the present application is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The present application is further described below in conjunction with the accompanying drawings. The same reference numerals in the drawings represent elements with the same functions. Among them:

[0017] Figure 1 A partial cross-sectional view showing a prior art seal cover assembled on a bearing;

[0018] Figure 2 A partial cross-sectional view showing a seal assembly according to an embodiment of the present application assembled on a bearing; and

[0019] Figure 3 A partial perspective view of a sealing assembly according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0020] The following will describe the specific implementation of the sealing assembly for bearings according to the present application in conjunction with the accompanying drawings. The following detailed description and accompanying drawings are used to exemplarily illustrate the principles of the present application. The present application is not limited to the preferred embodiments described, and the protection scope of the present application is defined by the claims.

[0021] The sealing assembly of the present application is applicable to sealing cylindrical roller bearings and tapered roller bearings of railways. However, those skilled in the art should also understand that the sealing assembly of the present application is also applicable to sealing other forms of bearings in other fields. In the present application, "axial direction" and "radial direction" are directions determined with reference to the bearing.

[0022] Figure 2 A partial cross-sectional view showing a seal assembly according to an embodiment of the present application assembled on a bearing. Figure 2 As shown, the bearing 2 includes an inner ring 21, an outer ring 22, rollers (not shown) and a cage 23. The rollers are located between the inner ring 21 and the outer ring 22 and can roll on their raceways. For example, the rollers are cylindrical rollers or tapered rollers. Each roller is fixed to each other at uniform intervals in its circumferential direction by the cage 23.

[0023] The sealing assembly 3 is annular in shape as a whole and is used to seal the internal space between the inner ring 21 and the outer ring 22. The sealing assembly 3 includes a frame 31 and a sealing member 32.

[0024] The skeleton 31 is annular as a whole, and when cut along a cross section parallel to the axial direction and passing through the center of the bearing 2, the cross section of the skeleton 31 is in a bent angular shape. For example, the skeleton 31 is formed of metal by a stamping process. The skeleton 31 includes a first bent portion 311 and a second bent portion 312. The first bent portion 311 abuts against the radial outer surface of the outer ring 22. The second bent portion 312 includes a first end portion and a second end portion opposite to each other, and the first end portion of the second bent portion 312 is connected to the first bent portion 311. In one example, the second bent portion 312 abuts against the axial end face of the outer ring 22.

[0025] The seal 32 includes a base 321, a first sealing lip 322, and a second sealing lip 323. The base 321 is annular as a whole and includes a first end and a second end opposite to each other. The first sealing lip 322 is annular as a whole and includes a first end and a second end opposite to each other. Similarly, the second sealing lip 323 is also annular as a whole. The first end of the base 321 is attached to the second end of the second bent portion 312, and the second end of the base 321 is attached to the first end of the first sealing lip 322. The first sealing lip 322 extends from the second end of the base 321 to the axial inner side of the bearing 2 and is inclined in the axial direction to contact with the radial outer surface of the inner ring 21 in an interference fit. The function of the first sealing lip 322 is to prevent grease leakage, so the first sealing lip 322 is interference fit with the radial inner surface of the inner ring 21 to reliably seal. The second sealing lip 323 extends obliquely from the second end of the base 321 toward the axial outer side of the bearing 2 and in the axial direction to the vicinity of the radial outer surface of the inner ring 21 or at the radial outer surface of the inner ring 21. The function of the second sealing lip 323 is to prevent the entry of external substances (for example, contaminants or water for cleaning the bearing 2), so the second sealing lip 323 only needs to be in quasi-contact with the radial outer surface of the inner ring 21, that is, in slight contact, or in non-contact with the radial outer surface of the inner ring 21 with a small gap.

[0026] Since the first sealing lip 322 is interference fit with the radial outer surface of the inner ring 21, and the second sealing lip 323 extends to the vicinity of the radial outer surface of the inner ring 21 or to the radial outer surface of the inner ring 21, the first sealing lip 322 of the sealing assembly 3 of the present application can reliably prevent grease from leaking from the inner space of the bearing 2, and the second sealing lip 323 can prevent foreign matter from entering the inner space. In addition, the cost of the sealing assembly 3 of the present application is low.

[0027] Since the first sealing lip 322 is used to prevent grease leakage, and the second sealing lip 323 is used to prevent foreign substances from entering, the thickness of the first sealing lip 322 is greater than that of the second sealing lip 323 .

[0028] The seal 32 is made of rubber, and the first end of the base 321 is attached to the second end of the second bent portion 312 by a vulcanization process. In one example, the first end of the base 321 is attached to both sides of the second end of the second bent portion 312 in the axial direction. In another example, the first end of the base 321 is attached to either side of the second end of the second bent portion 312 in the axial direction.

[0029] The first sealing lip 322 includes a PTFE sheet, which is disposed at the second end of the first sealing lip 322. For example, the PTFE sheet is bonded to the second end of the first sealing lip 322. By bonding PTFE to the first sealing lip 322, high friction torque can be avoided, thereby obtaining low friction performance. In this way, the sealing assembly 3 can be suitable for high-speed applications and can work for a long time.

[0030] The base 321 extends from the second end of the second bent portion 312 to the axial inner side of the bearing 2 at an angle to the axial direction. As a result, the first sealing lip 322 and the second sealing lip 323 can be away from the axial end surface of the inner ring 21. In one embodiment, the base 321 has a portion that is not attached to the second end of the second bent portion 312, and the axial inner surface of the portion is flush with the axial inner surface of the first sealing lip 322. In one embodiment, the axial outer surface of the base 321 is parallel to the axial end surface of the outer ring 22.

[0031] The base 321 is configured to have a specific thickness so as to ensure that the base 321 does not contact the retaining frame 23 due to deformation, and to ensure that the sealing assembly 3 is moved along the retaining frame 23. Figure 2 When the left side in the figure is assembled to the bearing 2, the first sealing lip 322 and the second sealing lip 323 will not be twisted or turned over.

[0032] Figure 3 FIG. 2 shows a partial stereoscopic view of a sealing assembly according to an embodiment of the present application. Figure 3 As shown, the base 321 has a portion of the second end portion that is not attached to the second bend portion 312, and the axial outer surface of the portion is provided with a pump liquid groove 324. The pump liquid groove 324 opens toward the axial outer side of the bearing 2 and toward the axial outer side of the second sealing lip 323, and the pump liquid groove 324 is adjacent to the second sealing lip 323. The pump liquid groove 324 can pump the liquid (for example, water) in the pump liquid groove 324 in a direction away from the bearing 2. The pump liquid grooves 324 can be evenly spaced along the circumference of the base 321. The pump liquid groove 324 can have two to five walls. Preferably, the pump liquid groove 324 has four walls. The wall of the pump liquid groove 324 is a flat surface. The angle between each wall and the axial direction is different, and multiple angles can increase the probability of contact with splashing water, and can pump away nearby splashing water to the greatest extent.

[0033] In one embodiment, considering the radial clearance of the cage 23, the axial movement, the safety distance between the sealing assembly 3 and the cage 23, the chamfer of the inner ring 21 and other factors, the angle between the first sealing lip 322 and the axial direction is between 15° and 70°, preferably 45°. The angle between the wall of the pump tank and the axial direction is between 10° and 65°, preferably 25°. As a result, the sealing assembly can not only improve the sealing performance, but also have a more compact structure to maximize the use of limited axial and radial space.

[0034] Although possible embodiments are described by way of example in the above description, it should be understood that there are still a large number of variations of embodiments through the combination of all known and other technical features and embodiments that are easily conceivable to the skilled person. It should also be understood that the exemplary embodiment is only an example and that such an embodiment in no way limits the scope of protection, application and configuration of the present application. The above description is more to provide the skilled person with a technical guide for converting at least one exemplary embodiment, wherein various changes can be made, especially changes in the functions and structures of the components, as long as they do not depart from the scope of protection of the claims.

[0035] Reference numerals list

[0036] 1 Sealing cover

[0037] 2 Bearings

[0038] 21 Inner Circle

[0039] 22 outer ring

[0040] 23 Cage

[0041] 3 Sealing components

[0042] 31 Skeleton

[0043] 311 first bending portion

[0044] 312 second bending portion

[0045] 32 Seals

[0046] 321 matrix

[0047] 322 first sealing lip

[0048] 323 Second sealing lip

[0049] 324 Pump Tank

Claims

1. A sealing assembly (3) for a bearing (2), wherein: The bearing (2) comprises an inner ring (21) and an outer ring (22); the sealing assembly (3) is annular in shape and is used to seal the internal space between the inner ring (21) and the outer ring (22); the sealing assembly (3) comprises: The frame (31) is in the shape of a bent angle and comprises a first bent portion (311) which abuts against the radial outer surface of the outer ring (22), and a second bending portion (312), a first end portion of the second bending portion (312) being connected to the first bending portion (312); and The sealing member (32) is annular in shape and comprises A base (321), wherein a first end of the base (321) is attached to a second end of the second bent portion (312) opposite to the first end, and a pump liquid groove (324) is provided on an axially outer surface of a portion of the base (321) not attached to the second end of the second bent portion (312), wherein the pump liquid groove has two to five flat walls, and each of the walls has a different angle with the axial direction. a first sealing lip (322), a first end of which is attached to a second end of the base (321) opposite to the first end of the base (321), and the first sealing lip (322) extends from the second end of the base (321) obliquely to the axial direction of the bearing (2) toward the axial inside of the bearing (2) to contact with the radial outer surface of the inner ring (21) in an interference fit, and A second sealing lip (323) extends obliquely from the second end of the base (321) and the axial direction of the bearing (2) toward the axial outside of the bearing (2) to near the radial outer surface of the inner ring (21) or at the radial outer surface of the inner ring (21), and the second sealing lip (323) is in slight contact with the radial outer surface of the inner ring (21) or is non-contact with the radial outer surface of the inner ring (21) with a small gap.

2. The sealing assembly (3) according to claim 1, wherein: The first sealing lip (322) includes a PTFE sheet, which is arranged at a second end of the first sealing lip (322) opposite to the first end of the sealing lip.

3. The sealing assembly (3) according to claim 1, wherein: The sealing member (32) is made of rubber, and the first end of the base (321) is attached to the second end of the second bent portion (312) by a vulcanization process.

4. The sealing assembly (3) according to claim 3, wherein: The first end of the base (321) is attached to both sides of the second end of the second bent portion (312) in the axial direction.

5. The sealing assembly (3) according to claim 1, wherein: The base (321) extends from the second end of the second bent portion (312) toward the axial inner side of the bearing (2) at an angle to the axial direction.

6. The sealing assembly (3) according to claim 1, wherein: The second bent portion (312) is in contact with the axial end surface of the outer ring (22).

7. The sealing assembly (3) according to claim 1, wherein: The thickness of the first sealing lip (322) is greater than the thickness of the second sealing lip (323).

8. The sealing assembly (3) according to claim 1, wherein: The angle between the first sealing lip (322) and the axial direction of the bearing (2) is between 15° and 70°, and the angle between the wall and the axial direction is between 10° and 65°.

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