Sealing device for a wheel bearing

Abstract

The invention relates to a sealing arrangement for a wheel bearing (1) having a first bearing part (3) and a second bearing part (5) which is integrally connected to a wheel bearing flange (7), between which bearing parts rolling bodies are guided, the sealing arrangement (1) comprising the following:-a support element (10), which is provided with a first bearing part (3) and a second bearing part (5) which is integrally connected to the wheel bearing flange (7), the invention relates to a bearing device (1) comprising a first bearing part (3), a second bearing part (5), and a carrier element (10) which is connected to the first bearing part (3) and on which an elastic element (11) is arranged, the elastic element (11) having at least one sealing lip (28, 29), the carrier element (10) having a fastening section which is connected to the first bearing part (3), a stop part (12) which is fastened to the second bearing part (5), the wheel bearing flange (7) has an axial projection (13), the axial projection (13) of the wheel bearing flange (7) being arranged in such a way that the projection projects in the direction of a cavity formed by the axial projection (14) of the first bearing part (3), and wherein the axial projection (14) of the first bearing part (3) is in sliding contact with the at least one sealing lip (28) of the wheel bearing flange (7). An inner surface (15) of an axial projection (13) of the wheel bearing flange (7) forms a seat for the stop portion (12).

Description

[0001] This application is a divisional application of the invention patent application titled "Sealing device for a wheel bearing" with an application date of November 05, 2020, a national application number of 202080071508.4 (PCT application number: PCT / DE2020 / 100948). Technical Field

[0002] The present invention relates to a sealing device for a wheel bearing, and more particularly to a sealing device for a wheel bearing of a motor vehicle. Background Art

[0003] For a wheel bearing, sliding seals on both sides of the space that houses the raceways and rolling elements and is filled with lubricant must ensure that neither solid particles nor corrosive media can penetrate into this space. Due to the possible slight tilting within the bearing during lateral acceleration while driving, there is a risk that the lip seals used will be lifted from the sliding surface. The seals used can interact with centrifugal disks made of formed metal sheets. The centrifugal disk connected to the rotating wheel hub or the wheel bearing flange can form an additional sealing labyrinth together with another metal sheet ring arranged in the fixed part of the wheel suspension. In addition, the sealing lips of at least one sealing ring extend in the axial direction or the radial direction and are guided on the centrifugal disk. The above-mentioned components of the seal can also be an integral part of a seal cartridge, in which the seal lip is axially prestressed in a defined manner.

[0004] Axially on the vehicle side of the wheel bearing, there is a mainly axially directed opening between the involved rotating mating parts, which is sometimes covered by the joint bell of an adjacent constant velocity joint. On the axial side of the wheel flange, the opening between the rotating mating parts of the wheel bearing is radially outwardly directed due to its proximity to the wheel flange and is very vulnerable to splashing water. Since the centrifugal disk made of metal sheet on the wheel flange produces a better friction-sealing contact than the inner part of the usually untreated wheel flange, the centrifugal disk is installed near the wheel flange before the wheel bearing is mounted on the wheel hub.

[0005] The sliding of the centrifugal disk can be triggered by impacts, continuous vibration loads, or other reasons, whereby the centrifugal disk on the outer surface axially approaches the rolling elements, and if the centrifugal disk comes into contact with the rolling elements, damage will be caused to both the centrifugal disk and the rolling elements. This leads to a failure of the wheel bearing.

[0006] A bearing seal for a wheel bearing is known from DE 10 2010 034 385 A1, in which the centrifugal disk is fixed to the wheel bearing flange, which is integrally connected to the rotating bearing ring of the wheel bearing. The sealing lips of the sealing device are supported on the centrifugal disk, which is coupled to another torsionally rigid bearing ring.

[0007] DE 10 2009 052 311 A1 describes a wheel bearing with a sealing device which, on the flange side, includes a centrifugal ring for sealing a roller bearing. In the installed state, the axial sealing lip is supported on the centrifugal disk via a friction seal contact. The sealing lip is associated with a carrier attached to the outer ring.

[0008] DE 103 58 876 A1 discloses a sealing device for a wheel bearing which uses two sealing rings to form an axial opening between two parts of the wheel bearing which can rotate relative to each other and to seal the wheel bearing axially. For this purpose, the two sealing rings form a gap-type labyrinth which has a capture channel with a sealing gap which is axially open and extends radially. SUMMARY OF THE INVENTION

[0009] The object of the present invention is to provide a sealing device which seals reliably during the service life and has an increased service life.

[0010] According to the present invention, this object is achieved by a sealing device for a wheel bearing which has a first support part and a second support part, the second support part being integrally connected to the wheel bearing flange and having rolling elements guided between the second support part and the wheel bearing flange, wherein the sealing device includes the following parts:

[0011] - a carrier element which is connected to the first support part, wherein an elastic element is provided on the carrier element, wherein the elastic element has at least one sealing lip and the carrier element has a fastening section connected to the first support part,

[0012] - a stop part which is fastened to the second support part and at least one sealing lip is in sliding contact with the stop part,

[0013] - wherein the wheel bearing flange has an axial projection,

[0014] The axial projection of the wheel bearing flange is arranged such that the projection projects in the direction of a cavity formed by the axial projection of the first support part, and wherein the inner surface of the axial projection of the wheel bearing flange forms a seat for the stop part.

[0015] In known sealing devices, the stop part is pulled onto the second support part in the region adjacent to the wheel bearing flange. However, this region of the seat of the stop part is one of the most stressed regions of the second support part and the wheel bearing flange. Under the excitation of high stresses caused by vibrations or the like, the starting part moves axially, for example. The axial migration causes the approaching part to approach the rolling elements, and if the approaching part comes into contact with the rolling elements, damage may be caused to both.

[0016] In the sealing device according to the invention, the wheel bearing flange thus has an axial projection, wherein the axial projection of the wheel bearing flange is arranged such that the projection projects in the direction of the cavity formed by the axial projection of the first support part, and wherein the inner surface of the axial projection of the wheel bearing flange forms a seat for the stop part. By means of this design, the seat of the sealing plate is moved out of the most stressed region. The fact that the contact part now sits on the axial projection of the wheel bearing flange means that movement of this contact part can be prevented. According to the prior art, in the region where the stop part is located, this is now non-contact. In addition, such a design has the advantage that, due to the arrangement of the projections relative to one another, there is sufficient mounting space on the wheel flange for fastening screws, and thus the rim and / or brake disc can be simply assembled / dismantled.

[0017] According to one embodiment of the invention, a first sealing gap is formed between the end face of the axial projection of the wheel bearing flange and the end face of the first support part. This sealing gap defines a pre-seal or a labyrinth seal. This makes it difficult for contaminants or the like to enter. At the same time, in the case of an axial impact acting on the second support part or the wheel bearing flange, the sealing gap transfers the resulting force from the wheel flange to the first support part. This prevents damage to the rolling elements.

[0018] The bearing element is preferably fastened to the inner peripheral surface of the first support part by means of a fastening section. This prevents the seat from being penetrated by contaminants or the like and prevents the occurrence of corrosion, which would have a negative impact on the sealing device.

[0019] According to one embodiment of the invention, the bearing element is designed such that the bearing element forms a free space, and the cage of the bearing projects into this free space. The support element has a path oriented in the direction of the wheel flange rather than in the direction of the bearing row. Thus, a free space is again created into which the cage of the bearing row can project. This has the advantage that the total installation space in the axial direction of the wheel bearing unit can be saved, and the wheel bearing unit is thus axially narrower.

[0020] According to one embodiment of the present invention, at least one first discharge channel is provided on the outer peripheral surface of the load-bearing element and / or the elastic element. This discharge channel enhances the sealing effect and prevents contaminants, etc. from entering the interior. The elastic element preferably provides a sealing lip that delimits the first discharge channel.

[0021] One embodiment of the present invention provides that the wheel bearing flange facing the wheel bearing is formed with a radially extending side surface and an outer surface, which abuts a rolling element raceway on the second support portion in the direction of the wheel bearing flange and receives a stop portion, and a radial and / or axial circumferential groove is arranged in the transition region between the outer surface and the side surface. The fact that the stop portion no longer has a seat in this region means that the groove or this region can be designed such that it results in an improvement in component strength. In each case, the groove can be arranged entirely or partially in the outer surface and / or the side surface.

[0022] The groove base of the groove preferably forms at least one radius. At least one radius of the groove can be adapted to different geometries of the wheel bearing flange to minimize stress in the transition region and increase component strength. A single radius as well as multiple radii can be provided.

[0023] A free space is preferably formed between the transition region of the stop portion and the groove base. Grease or sealant can accumulate in this free space and be optimally distributed, which further improves the assembly of the stop piece.

[0024] According to one embodiment of the present invention, at least one second discharge channel is provided on the outer peripheral surface of the first support portion. This second discharge channel enhances the sealing effect and prevents contaminants, etc. from entering the sealing labyrinth. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The exemplary embodiments of the present invention will be described below with reference to two drawings. In the drawings:

[0026] Figure 1 A longitudinal section of a wheel bearing having a sealing device according to the present invention is shown, and

[0027] Figure 2 An enlarged view of a sealing device according to a second embodiment of the present invention is shown. DETAILED DESCRIPTION OF THE INVENTION

[0028] Figure 1Shows a longitudinal section only partially showing the wheel bearing 1, which has a sealing device 2 according to the invention. The wheel bearing 1 has a first bearing part 3, which is designed as an outer ring 4 and is connected to a wheel carrier (not shown) during installation. A second bearing part 5 is also provided, which forms an inner ring 6. The second bearing part 5 has an integrally connected wheel bearing flange 7. Two rows of rolling elements 8, 9 are guided between the first bearing part 3 and the second bearing part 5.

[0029] Figure 2 The sealing device 1 of the wheel bearing 2 is shown in more detail in. This includes a carrier element 10, which is connected to the inner circumference of the first bearing part 3 by means of a press fit. An elastic element 11 is provided on the carrier element 10, wherein the elastic element 11 has at least one sealing lip. The carrier element 10 also has a fastening section for fastening to the first bearing part 3. In order to avoid rusting below the fastening section, a so-called static seal is formed by means of a sealing ring molded onto the elastic part.

[0030] The sealing device also has a stop part 12, which is fastened to the second bearing part 5, and two sealing lips 28 are in sliding contact on this stop part. It can also be seen that the wheel bearing flange 7 has an axial projection 13. The axial projection 13 is arranged such that it projects in the direction of a cavity formed by an axial projection 14 of the first bearing part 3. The internal space formed and delimited by the two bearing parts 3, 5 is considered to be the cavity. It can be said that the axial projection 13 extends in the direction of the rows of rolling elements 8, 9. Based on this design, a pre-seal is formed in the form of a labyrinth. Here, a first sealing gap is formed between the end face 16 of the axial projection 13 of the wheel bearing flange 7 and the end face 17 of the first bearing part 3. The end face 17 of the first bearing part is formed on the side that is radially adjacent to the projection 14 and extends radially away from the rows of rolling elements 8, 9.

[0031] Furthermore, the carrier element 10 is designed such that it forms a free space 30. The cage 31 of the row of rolling elements 8 projects into this free space 30.

[0032] In addition, the inner surface 15 of the axial projection 13 of the wheel bearing flange 7 forms a seat for the stop part 12. This eliminates the seat in the transition region between the second bearing part 5 and the wheel bearing flange 7 known in the prior art.

[0033] The radially extending side surface 18 abuts against the axially protruding portion 13. In addition, there is provided a second support portion 5 that abuts in the direction of the wheel bearing flange 7 and abuts against the outer surface 19 of the rolling element raceway. The outer surface 19 can be cylindrical and can have a conical shape. The outer surface 19 transitions into the radially extending side surface 18 in the transition region 20. In the transition region 20, circumferential grooves 21, which can be radial and / or axial, are formed. The grooves 21 can be adapted to the corresponding geometry of the wheel bearing flange 7. The groove base 22 of the groove 21 is formed with at least one radius. A free space 32 is formed between the groove base 22 and the stop portion 12. This free space 32 can be used for storing sealant, grease, etc.

[0034] In addition, as can be seen from Figure 2 it, a first discharge channel 25 is provided on the outer peripheral surface 23 of the elastic element 11. The first discharge channel 25 is delimited by the sealing lip 29. Second discharge channels 25, 26 are also provided on the outer peripheral surface 24 of the first support portion 3. These discharge channels 25, 26 form a kind of pre-seal, which is intended to reduce the entry of dirt into the interior of the bearing.

[0035] Explanation of reference numerals

[0036] 1 Wheel bearing 2 Sealing device 3 First support portion 4 Outer ring 5 Second support portion 6 Inner ring 7 Wheel bearing flange 8 Rolling element row 9 Rolling element row 10 Load-bearing element 11 Elastic element 12 Stop portion 13 Protrusion of the wheel bearing flange 14 Protrusion of the first support portion 15 Inner surface 16 End face 17 End face 18 Side surface 19 Outer surface 20 Transition region 21 Groove 22 Groove base 23 Outer peripheral surface 24 Outer peripheral surface 25 First discharge channel 26 Second discharge channel 28 Sealing lip 29 Sealing lip 30 Free space 31 Cage 32 Free space.

Claims

1. A sealing device for a wheel bearing (1), said wheel bearing having a first bearing part (3) and a second bearing part (5), said second bearing part being integrally connected to a wheel bearing flange (7), rolling elements being guided between said bearing parts, said sealing device (1) comprising the following: - A carrier element (10), said carrier element being connected to said first bearing part (3), an elastic element (11) being provided on said carrier element (10), said elastic element (11) having at least one sealing lip (28, 29), and said carrier element (10) having a fastening section connected to said first bearing part (3), - A stop part (12), said stop part being fastened to said second bearing part (5), and said at least one sealing lip (28) being in sliding contact with said stop part, - Said wheel bearing flange (7) having an axial projection (13), characterized in that said axial projection (13) of said wheel bearing flange (7) is arranged such that the projection projects in the direction of a cavity formed by an axial projection (14) of said first bearing part (3), and wherein an inner surface (15) of said axial projection (13) of said wheel bearing flange (7) forms a seat for said stop part (12), and, seen radially, the seat does not overlap with said axial projection (14) of said first bearing part (3), and the seat is removed from the most stressed area.

2. The sealing device according to claim 1, wherein an end face (16) of said axial projection (13) of said wheel bearing flange (7) and an end face (17) of said first bearing part (3) form a labyrinth seal.

3. The sealing device according to any one of the preceding claims, wherein said carrier element (10) is fastened to an inner peripheral surface of said first bearing part (3) by means of said fastening section.

4. The sealing device according to any one of the preceding claims, wherein said carrier element (10) is designed such that the carrier element forms a free space (30), and wherein a cage (31) of a bearing (8) projects into this free space (30).

5. The sealing device according to any one of the preceding claims, wherein at least one first discharge channel (25) is provided on an outer peripheral surface (23) of said carrier element (10) and / or said elastic element (11).

6. The sealing device according to claim 5, wherein said elastic element (11) provides a sealing lip (29) delimiting said first discharge channel (25).

7. The sealing device according to any one of the preceding claims, wherein The wheel bearing flange (7) facing the wheel bearing (1) is formed with a radially extending side surface (18) and an outer surface (19), the outer surface adjoining a rolling element raceway on the second support portion in the direction of the wheel bearing flange (7) and receiving the stop portion (12), and a circumferential groove (21) in the radial and / or axial direction is arranged in a transition region (20) between the outer surface (19) and the side surface (18).

8. The sealing device according to claim 7, wherein, the groove base (22) of the groove (21) is formed with at least one radius ().

9. The sealing device according to claim 8, wherein, a free space (32) is formed between the stop portion (12) and the groove base (22).

10. The sealing device according to any one of the preceding claims, wherein, at least one second discharge channel (26) is provided on the outer peripheral surface (24) of the first support portion (3).

Images