WHEEL BEARING UNIT AND METHOD FOR MANUFACTURING A SEAL UNIT OF A WHEEL BEARING UNIT

Abstract

A wheel bearing unit includes a first inner ring having an axial end side, a second inner ring having an axial end side contacting the axial end side of the first inner ring at a joint, and a seal unit that seals the joint between the first inner ring and the second inner ring. The seal unit includes at least one seal element and at least one further component that exerts pressure on the at least one seal element, and the at least one further component is at least partially comprised of sheet metal.

Claims

1. A wheel bearing unit comprising: a first inner ring having an axial end side, a second inner ring having an axial end side contacting the axial end side of the first inner ring at a joint, and a seal unit that seals the joint between the first inner ring and the second inner ring, the seal unit including at least one seal element and at least one further component that exerts pressure on the at least one seal element, wherein the at least one further component is at least partially comprised of sheet metal.

2. The wheel bearing unit according to claim 1, wherein the at least one further component is completely comprised of sheet metal and/or is configured one-piece.

3. The wheel bearing unit according to claim 1, wherein the component includes a sheet metal ring or is a sheet metal ring.

4. The wheel bearing unit according to claim 3, wherein the sheet metal ring is manufactured from a sheet metal strip having a first end and a second end, the first and second ends being attached to each other in an interference-fit and/or material-bonded manner.

5. The wheel bearing unit according to claim 4, wherein the first end has a dovetail shape.

6. The wheel bearing unit according to claim 1, wherein the seal unit is disposed on radial outer sides of the first and second inner rings.

7. The wheel bearing unit according to claim 1, wherein the seal element comprises an O-ring, and wherein the at least one further component comprises a sheet metal ring formed from a sheet metal strip having a first end connected to a second end, the sheet metal ring having a radially inwardly facing circumferential channel, and wherein the O-ring is mounted in the channel and radially overlies the joint.

8. The wheel bearing unit according to claim 7, wherein the first end comprises a dovetail, wherein the second end comprises an opening substantially complementary to the dovetail, and wherein the first end and the second end each include at least one impression at a junction of the dovetail and the opening.

9. A component for securing a seal ring to a bearing ring comprising a deformed sheet metal strip having a first end attached to a second end and including a receiving channel configured to at least partial receive a seal ring.

10. A method for manufacturing a wheel bearing unit, comprising: placing an axial end surface of a first bearing inner ring in contact with an axial end surface of a second bearing inner ring such that the axial end surface of the first bearing inner ring and the axial end surface of the second bearing inner ring form a joint, providing the component according to claim 9, placing the seal ring into the channel, and installing the deformed sheet metal strip and seal ring over the joint such that the deformed sheet metal strip holds the seal ring against the joint.

11. A method for manufacturing a seal unit of a wheel bearing unit comprising bending a sheet metal strip into a ring and attaching a first end of the ring to a second end of the ring.

12. The method according to claim 11, wherein the first end is attached to the second end in an interference-fit and/or material-bonded manner.

13. The method according to claim 12, wherein the first end has a dovetail shape.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG. 1 is a partial axial section through a portion of a conventional wheel bearing unit.

[0021] FIG. 2 is a securing ring of a seal of the wheel bearing unit of FIG. 1.

[0022] FIG. 3 is an axial section through the seal of FIG. 2.

[0023] FIG. 4 is an axial section through a wheel bearing unit according to an embodiment of the present disclosure.

[0024] FIG. 5 is a perspective view of part of a seal unit of the wheel bearing unit of FIG. 4.

[0025] FIG. 6 is part of an axial section through the seal unit of FIG. 5.

[0026] FIG. 7 is a perspective view of the seal unit of FIG. 5 illustrating an attachment point.

DETAILED DESCRIPTION

[0027] FIG. 4 shows a section through a wheel bearing unit 34 along an axial direction of the wheel bearing unit 34. The wheel bearing unit 34 includes a first rolling-element bearing 32 including a first inner ring 31, and a second rolling-element bearing 38 including a second inner ring 36. An end side 40 of the second inner ring 36 abuts against an end side 42 of the first inner ring 31. An outer ring 66 of the wheel bearing unit forms an outer raceway 62 of the rolling-element bearing 32 and an outer raceway 64 of the rolling-element bearing 38. Rolling elements 68 are disposed between the raceway 62 and the inner ring 31. Furthermore, rolling elements 70 are disposed between the inner ring 36 and the raceway 64. In the present case all rolling elements 68, 70 are configured as tapered rollers. The inner rings 31, 36 are pressed against each other in the axial direction by a nut (not depicted).

[0028] In a spatial region that is axially between the rolling elements 68 and the rolling elements 70, the wheel bearing unit includes a seal unit 44 that seals between the inner rings 31, 36. The seal unit 44 comprises a seal element 46 that abuts against both inner rings 31, 36. The seal element 46 is configured as an O-ring and abuts against both inner rings continuously along its entire circumference and specifically against radial outer sides 54, 56 of the inner ring 31, 36. In addition, the seal unit 44 comprises a component 48 that exerts a radially inward pressure on the seal element 46, which is continuously present along an entire radially outer circumference of the seal element 46. The component 48 is a sheet metal ring configured one-piece, and is formed entirely of sheet metal.

[0029] The component includes a first region 72 and a second region 74, which each have a shape of a hollow cylinder in an axial section (FIG. 6). In the axial direction between the regions 72, 74, the component 48 has a bulge 76 that extends radially outwardly and thus forms a receiving region 58 on its radially inner side. Both the bulge 76 and the receiving region 58 have annular shape and enclose the inner rings 31, 36. As already mentioned, the seal element 46 is a seal ring 60 and partially disposed in the receiving region 58.

[0030] The manufacture of the component 48 begins with a sheet metal strip. This initially has essentially a shape of a rectangle. In a fully manufactured state of the component 48, ends 50, 52 of the sheet metal strip are attached to each other (FIGS. 5 and 7). During the manufacturing of the component 48, the ends 50, 52 are first processed. Here the end 50 is brought into a shape of a dovetail, and the end 52 is provided with an opening that also has a shape generally complementary to that of the dovetail. The bulge 76 is then generated by deforming the sheet metal strip. In a further step, the deformed sheet metal strip is bent into a ring, and the dovetail of the end 50 is introduced into the opening of the end 52 such that an interference-fit attaching of the two ends 50, 52 to each other is generated in the circumferential direction of the ring. Despite the interference-fit attaching of the two ends 50, 52 to each other, a small gap is still formed between the ends. For further improvement of the interference-fit attachment of the two ends to each other, impressions 78, 80, 82, 84 are also made inward in the radial direction at the ends 50, 52. Due to these impressions, a closing of the gap between the ends 50, 52 is at least largely, or completely, achieved. In addition, an attaching of the ends 50, 52 to each other is effected in the radial direction in a friction-fit manner. Overall, a very substantial reduction of the risk of the ends 50, 52 moving apart is achieved. Two impressions 82 are disposed on two tips of the dovetail of the end 50. Two impressions 78 are disposed on an axially outer region of the end 50 where the end 50 still has its entire axial width. Two impressions 80 are disposed on tips of the end 52 that lie axially inward. Two further impressions 84 are disposed on the end 52 opposite the impressions 82. After attaching the ends 50, 52 to each other, the seal element 46 is inserted into the receiving region 58. The method for manufacturing the seal unit is a part of the method for the manufacturing of the wheel bearing unit.

[0031] In principle, the ends 50, 52 can also be attached to each other in other ways, such as in particular by welding.

[0032] The essentially rotationally symmetric construction of the component 48 causes the component 48 to exert a pressure on the seal element 46 in the circumferential direction over the entire surface radially inward onto the inner rings, whereby a very particularly reliable seal is effected between the inner rings 31, 36.

[0033] The component 48 is thus also manufactured extremely efficiently, even in embodiments having different diameters. Due to the construction from sheet metal, no cost-intensive injection-molding tool is required as would be the case with a construction made of plastic. The sheet metal strip for manufacturing the component 48 can be cut to size in the correct length from a roll including metal tape that already has the desired thickness. Embodiments of the component 48 having different diameter can easily be formed by bending sheet metal strips having different length into the desired ring having the desired diameter. These different embodiments of the component 48 having different diameter can even be implemented in a single configuration of the machine used.

[0034] Representative, non-limiting examples of the present invention were described above in detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the invention. Furthermore, each of the additional features and teachings disclosed above may be utilized separately or in conjunction with other features and teachings to provide improved seal unit for a wheel bearing.

[0035] Moreover, combinations of features and steps disclosed in the above detailed description may not be necessary to practice the invention in the broadest sense, and are instead taught merely to particularly describe representative examples of the invention. Furthermore, various features of the above-described representative examples, as well as the various independent and dependent claims below, may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings.

[0036] All features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter, independent of the compositions of the features in the embodiments and/or the claims. In addition, all value ranges or indications of groups of entities are intended to disclose every possible intermediate value or intermediate entity for the purpose of original written disclosure, as well as for the purpose of restricting the claimed subject matter.

REFERENCE NUMBER LIST

[0037] 10 Fitting surface [0038] 12 Fitting surface [0039] 14 Inner ring [0040] 16 Inner ring [0041] 18 Seal [0042] 20 Bearing raceway [0043] 22 Bearing raceway [0044] 24 Seal ring [0045] 26 Securing ring [0046] 28 Tooth [0047] 31 Inner ring [0048] 32 Rolling-element bearing [0049] 34 Wheel bearing unit [0050] 36 Inner ring [0051] 38 Rolling-element bearing [0052] 40 End side [0053] 42 End side [0054] 44 Seal unit [0055] 46 Seal element [0056] 48 Component [0057] 50 End [0058] 52 End [0059] 54 Outer side [0060] 56 Outer side [0061] 58 Receiving region [0062] 60 Seal ring [0063] 62 Raceway [0064] 64 Raceway [0065] 66 Outer ring [0066] 68 Rolling element [0067] 70 Rolling element [0068] 72 Region [0069] 74 Region [0070] 76 Bulge [0071] 78 Impression [0072] 80 Impression [0073] 82 Impression [0074] 84 Impression