Bearing device with sealing assembly

Abstract

The invention relates to a bearing device with a sealing assembly, which is arranged between a first bearing ring and a second bearing ring of the bearing device, which can rotate relatively, so as to dynamically seal the first bearing ring and the second bearing ring, the sealing assembly comprises a first sealing body fixed to the first bearing ring and a second sealing body fixed to the second bearing ring, a gap opening is formed between the first sealing body and the second sealing body, and the first sealing body is provided with a first sealing lip and a contact lip making contact with the second sealing body. The first sealing lip is provided with a plurality of first sub-lips protruding outwards in the radial direction, first containing grooves are formed between the first sub-lips, all the first sub-lips of the first sealing lip jointly form a circular truncated cone shape, and the diameters of the first sub-lips are gradually increased in the flowing direction towards the gap opening.

Description

Bearing device with sealing assembly Technical Field

[0001] This invention relates to sealing technology for bearings, specifically dynamic sealing technology. Bearings in wheel hub drive systems, for example, typically utilize a typical seal assembly structure consisting of a frame, rubber, a sealing lip, and a contact lip, installed between the bearing's inner and outer rings. This seal assembly is used to seal grease within the bearing while keeping contaminants and muddy water out. Background Art

[0002] In mechanical components that rotate relative to each other, such as bearings, sealing devices are often required to prevent grease leakage and contaminants from entering. Such sealing devices typically consist of a frame, an elastic sealing body, and a sealing lip. The frame is mounted on the bearing ring, the elastic sealing body is fixed to the frame through vulcanization or other methods, and the sealing lip extends from the sealing body and provides a contact or non-contact seal to prevent internal lubricant leakage and external contaminants from entering.

[0003] WO 2023 / 040418 A1 discloses a sealing device comprising an annular elastic sealing body and a rigid annular member, the elastic sealing body being fixed to the rigid annular member. The elastic sealing body comprises a base and at least one sealing lip extending away from the base. The sealing lip comprises a foam layer having multiple cellular structures formed on its surface, and also includes a wear-resistant coating formed on the foam layer. This specially manufactured sealing lip is complex to manufacture, requiring additional processing steps and increasing manufacturing costs.

[0004] In today's wheel hub drive industry, high rotational speeds are often required, necessitating that seal assemblies generate minimal frictional torque. To meet this low frictional torque requirement, only one sealing lip is typically designed as a contact lip, while the remaining centrifugal lip and dust lip are designed as non-contact lips. While such seal assemblies may meet the low frictional torque requirement, they struggle to pass the industry-required mud and water jet contamination tests for a certain period of time. In other words, existing seal assemblies with low frictional torque typically exhibit poor sealing performance. Improving this performance requires specialized processing of the contact lip, further increasing manufacturing costs.

[0005] Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to provide a bearing device including a sealing assembly with reliable sealing performance and low friction torque.

[0007] This technical problem is solved by a bearing assembly having a sealing assembly designed according to the present invention. The sealing assembly is installed between a first bearing ring and a second bearing ring of the bearing assembly, which are capable of relatively rotating, to dynamically seal the first and second bearing rings. The sealing assembly includes a first sealing body fixed to the first bearing ring and a second sealing body fixed to the second bearing ring. A gap is provided between the first and second sealing bodies to ensure that the first and second sealing bodies contact only at the contact lip. The gap is also used to utilize centrifugal force to flush out muddy water and dirt within the sealing assembly. The first sealing body has a first sealing lip and a contact lip in contact with the second sealing body, the first sealing lip has a plurality of first sub-lips protruding in the radial direction of the bearing device away from the interior of the bearing, and a first accommodating groove is provided between the first sub-lips, wherein all the first sub-lips of the first sealing lip are frustum-shaped, and the diameter of the first sub-lip gradually increases in the flow direction toward the gap opening, so that the first sub-lip forms a frustum side surface with a certain slope on the first sealing lip, so that the muddy water inside the sealing assembly is more easily discharged when the bearing device is working, and when the muddy water enters the interior of the sealing assembly through the gap opening, it can first be stored in the accommodating groove and then discharged when the bearing is working. The flow direction refers to the fluid flow path within the sealing assembly. When the bearing device is not working, muddy water and other fluids may enter from the gap opening and flow within the sealing assembly. Therefore, it is preferred that the receiving groove gradually increases in the flow direction toward the gap opening, that is, when muddy water and other fluids flow into the seal, they are first stored in the larger receiving groove, thereby greatly reducing the flow into the interior of the sealing assembly; when the bearing device rotates, that is, when the first bearing ring and the second bearing ring rotate relative to each other, muddy water and other fluids flow out of the sealing assembly along the flow direction toward the gap opening under the action of centrifugal force, thereby improving the sealing effect with the additional contact lip.

[0008] According to a preferred embodiment of the present invention, the gap opening is formed on the radially outer side of the first sealing body and the second sealing body. The direction of the gap opening is the same as the direction of the centrifugal force on the sealing assembly, and therefore is more conducive to improving the effect of the centrifugal force and is more conducive to the discharge of mud, water and pollutants. It is further preferred that the first sub-lips are arranged on the radial inner side of the gap opening and on one axial side of the gap opening, so that the mud, water and pollutants entering the sealing assembly from the gap opening will pass through the first sub-lip in sequence, thereby improving the blocking efficiency of the first sub-lip for mud, water and pollutants. It is further preferred that the first sub-lip and the radial wall corresponding to the first sub-lip of the second sealing body form a labyrinth seal. The first sub-lip is radially close to the rubber wall corresponding to it, but does not contact it, thereby forming a labyrinth seal to further block the entry of mud, water and pollutants.

[0009] According to a preferred embodiment of the present invention, the second sealing body includes a second sealing lip radially inward of the first sealing lip. The interaction between the second sealing lip and the first sealing lip increases the flow path for muddy water and contaminants, thereby improving the sealing effect. Further preferably, the second sealing lip includes multiple second sub-lips protruding radially outward, with a second receiving groove provided between the second sub-lips. All of the second sub-lips of the second sealing lip are truncated cone-shaped, with the diameter of the second sub-lips gradually increasing in the direction of flow toward the gap opening. Similar to the first sealing lip, providing a second sealing lip with a second sub-lip in the flow path of fluids such as muddy water can improve the sealing effect. Furthermore, when the first and second sealing bodies rotate relative to each other, the stepped arrangement of the second sub-lips allows muddy water to be more easily discharged from the sealing assembly. Further preferably, the second sub-lip and the radially corresponding side of the first sealing lip form a labyrinth seal. The second sub-lips are close to the first sealing lip but do not contact it, forming a labyrinth seal that further blocks muddy water and contaminants. It is also conceivable that the radial depth of the first receiving groove between the first sub-lips and / or the second receiving groove of the second sub-lip gradually decreases in the flow direction toward the gap opening. Since the radial height of the first sub-lip and the second sub-lip gradually increases in the flow direction of the fluid, the radial depth of the receiving groove corresponds thereto, making it easier for the fluid stored in the receiving groove to flow out of the gap opening. It is also preferred that the axial width of the first receiving groove and / or the second receiving groove gradually increases in the flow direction toward the gap opening, so that the closer the first sub-lip and the second sub-lip are to the gap opening, the wider the receiving groove is, which can accommodate more muddy water and pollutants, thereby reducing the flow into the interior of the sealing assembly.

[0010] According to a preferred embodiment of the present invention, the sealing assembly has a guide groove on the radially outward end face. The guide groove is formed on the side facing the outside, which can store muddy water and dirt, and can guide the muddy water and dirt away from the gap opening. It is also preferred that the sealing assembly has a pump groove at the gap opening. When the bearing device is not working, the pump groove can be used to temporarily store muddy water and dirt that flow into the sealing assembly through the gap opening; when the bearing device rotates at high speed, the pump groove can provide a certain pumping force to throw the muddy water and dirt out of the gap opening. Another technical solution that can be considered is that the sealing assembly is placed between the first bearing ring and the second bearing ring through an interference fit, which is convenient for installation and does not require additional fixing components and process flows, thereby reducing assembly costs and component costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The preferred embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0012] FIG1 is a cross-sectional view of a bearing device according to the prior art;

[0013] FIG. 2 is a cross-sectional view of a sealing assembly according to the present invention.

[0014] Corresponding reference numerals in the figures indicate components with the same or similar functions. In the present invention, directions such as "axial" and "radial" are relative to the bearing. Radially outward and radially outside refer to directions radially away from the bearing assembly, while radially inward and radially inside refer to directions radially toward the interior of the bearing assembly. DETAILED DESCRIPTION

[0015] The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0016] Figure 1 shows a cross-sectional view of a bearing device. The bearing device includes a first bearing ring 1 and a second bearing ring 2. The first bearing ring 1 and the second bearing ring 2 rotate relative to each other, and a large amount of grease is contained in the cavity between them. Therefore, a sealing assembly 3 needs to be provided between the first bearing ring 1 and the second bearing ring 2. The bearing device according to the present invention is preferably installed on a wheel hub drive system. Therefore, the relative movement between the first bearing ring 1 and the second bearing ring 2 is usually relatively fast, and is also more susceptible to invasion by dirt such as mud and water. In order to better prevent foreign matter from entering the interior of the bearing device, multiple contact lips are usually provided between the first bearing ring 1 and the second bearing ring 2. However, due to the relative movement, the contact lips generate a large friction torque, which not only affects the rotation of the bearing device but also reduces the life of the sealing assembly. Therefore, how to ensure that the sealing requirements are met while minimizing the contact lips is the core technical problem to be solved by the present invention.

[0017] Figure 2 shows a sealing assembly 3 designed according to the present invention, which is arranged between the first bearing ring 1 and the second bearing ring 2. The sealing assembly 3 includes a first sealing body 31 and a second sealing body 32, with a gap 33 provided between the first sealing body 31 and the second sealing body 32. The first sealing body 31 is abutted against, and preferably fixed to, the first bearing ring 1, and the second sealing body 32 is abutted against, and preferably fixed to, the second bearing ring 2. The first sealing body 31 and the second sealing body 32 are capable of relative rotation and form a dynamic seal therebetween. The first sealing body 31 has a first sealing lip 311 and is supported by a first skeleton 312. The second sealing body has a second sealing lip 321 and is supported by a second skeleton 322.

[0018] The first sealing body 31 has a contact lip 314 for contacting the second sealing body 32 to form a dynamic seal. The first sealing lip 311 has three sub-lips 3110, 3111, and 3112. All three sub-lips protrude radially outward, and there is a receiving groove between them to temporarily accommodate muddy water entering the interior from the gap opening 33. The three sub-lips are arranged in a truncated cone shape, and the closer the sub-lip is to the gap opening 33, the larger the diameter is. The radial depth of the receiving groove corresponds to the radial height of the sub-lip, and the axial width of the receiving groove increases the closer it is to the gap opening 33, thereby minimizing the amount of muddy water and contaminants entering the interior of the sealing component. As shown in Figure 2, the arrows in the figure indicate the flow direction of muddy water flowing into the interior under the action of centrifugal force when the bearing is working. Due to the truncated cone arrangement of the sub-lips, muddy water can more easily flow out of the gap opening 33, thereby reducing the amount of muddy water inside the sealing component 3. As shown in Figure 2 , the second sealing body 32 also includes a second sealing lip 321 with a similar structure. The second sealing lip 321 has two radially outwardly projecting sub-lips with a receiving groove disposed therebetween. The second sealing lip 321 is radially inward of the first sealing lip 311. The second sub-lip of the second sealing lip 321 is also truncated conical in shape.

[0019] As shown in Figure 2, multiple guide grooves 324 are provided on the radially outer portion of the second sealing body 32 to collect contaminants and muddy water and direct them away from the sealing lip. Furthermore, a first pumping groove 313 is provided on the side of the first sealing body 31 facing the bearing interior to better prevent grease from flowing out and reduce pressure on the contact lip 314. As the seal assembly 3 rotates, the first pumping groove 313 pushes grease back into the bearing to lubricate the rollers. Furthermore, a second pumping groove 323 is provided near the gap opening 33 to temporarily store muddy water and provide pumping force during bearing operation. If muddy water and contaminants enter the seal assembly 3, they will be blocked for a long time by the labyrinth seals formed between the first and second sealing lips and their sub-lips. As the seal assembly rotates (i.e., when the first and second sealing bodies rotate relative to each other), the centrifugal force and pumping force provided by the sealing lips and pumping grooves easily expel the muddy water and contaminants from the seal assembly 3.

[0020] Because the entire sealing assembly consists of a single, thin, and uncoated contact lip 314, the frictional torque caused by this contact lip 314 is extremely low. The design of the present invention ensures sealing performance through the labyrinth seal and groove seal formed by several non-contact lips and a single contact lip. Therefore, the sealing assembly of the present invention exhibits both low frictional torque and high sealing performance.

[0021] Although possible embodiments have been described by way of example in the above description, it should be understood that there are still a large number of variations of embodiments by combining all known and readily conceivable technical features and implementations. It should also be understood that the exemplary implementation is merely an example and that such an embodiment in no way limits the scope of protection, application and construction of the present invention. The foregoing description is more of a technical guide for the technician to transform at least one exemplary embodiment, wherein various changes can be made to the technical staff without departing from the scope of protection of the claims, in particular with regard to the function and structure of the components. List of Figures 1 First bearing ring 2 Second bearing ring 3 Sealing assembly 31 First sealing body 311 First sealing lip 3110, 3111, 3112 First sub-lip 312 First skeleton 313 First pump groove 314 Contact lip 32 Second sealing body 321 Second sealing lip 322 Second skeleton 323 Second pump groove 324 Guide groove 33 Gap opening

Claims

1. A bearing device having a sealing assembly (3), further comprising a first bearing ring (1) and a second bearing ring (2), wherein the sealing assembly (3) is installed between the first bearing ring (1) and the second bearing ring (2) of the bearing device which are capable of relatively rotating, so as to dynamically seal the first bearing ring (1) and the second bearing ring (2), wherein: The sealing assembly (3) comprises a first sealing body (31) fixed on the first bearing ring (1) and a second sealing body (32) fixed on the second bearing ring (2), a gap opening (33) is provided between the first sealing body (31) and the second sealing body (32), the first sealing body (31) has a first sealing lip (311) and a contact lip (314) in contact with the second sealing body (32), the first sealing lip (311) has a plurality of first sub-lips (3110, 3111, 3112) protruding radially outward, a first receiving groove is provided between two adjacent first sub-lips (3110, 3111, 3112), wherein all the first sub-lips of the first sealing lip (311) together form a truncated cone shape, and the diameters of the first sub-lips (3110, 3111, 3112) gradually increase in the flow direction toward the gap opening (33).

2. The bearing device with a sealing assembly (3) according to claim 1, characterized in that: The gap opening (33) is formed on the radially outer sides of the first sealing body (31) and the second sealing body (32).

3. The bearing device with a sealing assembly (3) according to claim 2, characterized in that: The first sub-lips (3110, 3111, 3112) are all arranged on the radial inner side of the gap opening (33) and located on one axial side of the gap opening.

4. The bearing device with a sealing assembly (3) according to claim 3, characterized in that: The first sub-lip (3110, 3111, 3112) and the wall surface of the second sealing body (32) corresponding to the first sub-lip (3110, 3111, 3112) in the radial direction form a labyrinth seal.

5. The bearing device with a sealing assembly (3) according to claim 1, characterized in that: The second sealing body (32) has a second sealing lip (321) on the radial inner side of the first sealing lip (311).

6. The bearing device with a sealing assembly (3) according to claim 5, characterized in that: The second sealing lip (321) has a plurality of second sub-lips protruding radially outward, and a second receiving groove is provided between two adjacent second sub-lips, wherein all the second sub-lips of the second sealing lip (321) are collectively truncated cone-shaped, and the diameter of the second sub-lips gradually increases in the flow direction toward the gap opening (33).

7. The bearing device with a sealing assembly (3) according to claim 6, characterized in that: The second sub-lip and a radial side surface of the first sealing lip (311) corresponding to the second sub-lip form a labyrinth seal.

8. The bearing device with a sealing assembly (3) according to claim 6, characterized in that: The radial depth of the first accommodating groove and / or the second accommodating groove gradually decreases in the flow direction toward the gap opening (33).

9. The bearing device with a sealing assembly (3) according to claim 6, characterized in that: The axial width of the first accommodating groove and / or the second accommodating groove gradually increases in the flow direction toward the gap opening (33).

10. A bearing device having a sealing assembly (3) according to any one of claims 1 to 9, characterized in that: The sealing component (3) has a guide groove (324) on the radially outward end surface.

11. A bearing device with a sealing assembly (3) according to any one of claims 1 to 9, characterized in that: The sealing component (3) has a pump groove (323) at the gap opening (33).

12. A bearing device with a sealing assembly (3) according to any one of claims 1 to 9, characterized in that: The sealing assembly (3) is engaged between the first bearing ring (1) and the second bearing ring (2) in an interference fit manner.

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