BEARING ASSEMBLY, USE OF THE BEARING ASSEMBLY, AND METHOD FOR MANUFACTURING THE BEARING DEVICE

Abstract

A bearing assembly includes an outer element and an inner element and at least two rows of rolling elements supporting the inner element in the outer element for relative rotation. The outer element includes two surface regions for contact with the rolling elements, and the inner element includes two surface regions for contact with the rolling elements, and the rolling elements of at least one of the rows are rollers.

Claims

1. A bearing assembly comprising: an outer element and an inner element and at least two rows of rolling elements supporting the inner element in the outer element for relative rotation, wherein the outer element includes two surface regions for contact with the rolling elements, and the inner element includes two surface regions for contact with the rolling elements, wherein the rolling elements of at least one of the rows are embodied as rollers.

2. The bearing assembly according to claim 1, further comprising a retaining element for the rollers that is held on the inner element or on the outer element and includes a slip surface for the rollers.

3. The bearing assembly according to claim 1, wherein the inner element or the outer element includes an at least partially radially extending abutment surface, against which the retaining element abuts.

4. The bearing assembly according to claim 1, further comprising a bearing cage for guiding the rollers, wherein the bearing cage is configured such that it is at least temporarily radially expandable.

5. The bearing assembly according to claim 1, wherein the inner element includes a radially inner-lying recess into which a shaft part connectable to the inner element is insertable.

6. The bearing assembly according to claim 1, wherein the outer element includes a retaining element, by which the bearing assembly is retainable on a housing.

7. A motor vehicle wheel unit including the bearing assembly according to claim 1.

8. A method for manufacturing, the bearing assembly according to claim 1, comprising: manufacturing the inner element, of the outer element, and of the rolling elements of the first row and of the rollers of the second row, introducing a first of the rows of rolling elements into the outer element, introducing the inner element into the outer element such that the first row of rolling elements is contacted by the corresponding surface regions of the inner element and of the outer element, and introducing the rollers between the outer element and the inner element such that the rollers are contacted by the corresponding surface regions of the inner element and of the outer element.

9. The method according to claim 8, wherein the retaining element is inserted after the introduction of the rollers of the second row of rolling elements.

10. The method according to claim 9, further including the following steps prior to the inserting of the retaining element: measuring of the distance of an outer end side of the rollers from the abutment surface for the retaining element, and depending on the measured distance, processing the retaining element such that with later abutting of the retaining element against the abutment surface, the end side of the rollers is acted upon by the slip surface of the retaining element with a predetermined contact force.

11. The bearing assembly according to claim 1, wherein the outer element comprises a unitary outer bearing ring and the inner element comprises a unitary inner bearing ring, wherein the two surface regions of the outer bearing ring comprise a first raceway and a second raceway and the two surface regions of the inner bearing ring comprise a first raceway and a second raceway, wherein the rolling elements include a first plurality of rolling elements between the first raceway of the outer bearing ring and the first raceway of the inner bearing ring and a second plurality of rolling elements, the second plurality of rolling elements comprising rollers. wherein the first raceway of the outer ring is bounded by a flange formed integrally with the outer ring, and wherein the outer ring and the inner ring are configured such that the second plurality of rolling elements are insertable between the second raceway of the outer ring and the second raceway of the inner ring when the first plurality of rolling elements are in direct contact with both the first raceway of the outer ring and the first raceway of the inner ring.

12. The bearing assembly according to claim 11, wherein the first plurality of rolling elements and the second plurality of rolling elements are arranged in a back-to-back configuration.

13. A bearing assembly comprising: a unitary outer ring having a first raceway and a second raceway, a unitary inner ring having a first raceway opposing the first raceway of the outer ring and a second raceway opposing the second raceway of the outer ring, and a first plurality of rolling elements in direct contact with the first raceway of the outer ring and the first raceway of the inner ring, wherein the inner ring and the outer ring are configured such that a second plurality of rolling elements comprising ropers are insertable between the second raceway of the outer ring and the second raceway of the inner ring when the first plurality of rolling elements are in contact with both the first raceway of the outer ring and the first raceway of the inner ring.

14. The bearing assembly according to claim 13, including the second plurality of rolling elements and a retaining ring mounted between the inner ring and the outer ring in direct contact with axial ends of the second plurality of rolling elements.

15. The bearing assembly according to claim 14, wherein the first plurality of rolling elements and the second plurality of rolling elements are arranged in a back-to-back configuration.

16. A method comprising providing a unitary outer ring having a first raceway and a second raceway, providing a unitary inner ring having a first raceway and a second raceway, placing a first plurality of rolling elements mounted in a cage, against the first raceway of the outer ring, inserting, the inner ring axially through the outer ring such that the first plurality of rollers contact the first raceway of the inner ring and are held against the first raceway of the outer ring by the inner ring and such that the second raceway of the inner ring opposes the second raceway of the outer ring, and inserting a second plurality of rolling elements, comprising rollers, into a space between the second raceway of the inner ring, and the second raceway of the outer ring.

17. The method according to claim 16, including: after inserting the second plurality of rolling elements, inserting a retaining ring into a space between the inner ring and the outer ring and in contact with axially outer surfaces of the rollers to form a flange for guiding the rollers.

18. The method according to claim 17, wherein the first plurality of rolling elements and the second plurality of rolling elements are arranged in a back-to-back configuration.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] FIG. 1 is a sectional elevational view of an upper region of a wheel bearing assembly according to an embodiment of the present invention.

[0026] FIG. 2 is a detail view of region II in FIG. 1.

[0027] FIG. 3 is a sectional elevational view of an upper region of a wheel bearing assembly according to another embodiment of the present invention.

[0028] FIG. 4 is a flow chart illustrating a method according to the present disclosure.

DETAILED DESCRIPTION

[0029] FIG. 1 shows the upper region of a longitudinal section through a wheel bearing assembly 1 according to one embodiment of the disclosure that is suitable for the retaining and supporting a wheel on a motor vehicle. It comprises an outer ring 3 and an inner ring 5, wherein the inner ring 5 is disposed inside the outer ring 3. The wheel bearing assembly 1 further includes two axially spaced rows of rolling elements that are listed here as tapered rollers 7 and 9. The outer ring 3 includes two raceways 11 and 13 for the tapered rollers 7 and 9. The inner ring 5 also includes two raceways 15 and 17 for the tapered rollers 7 and 9. The tapered rollers 7 are disposed between the raceways 11 and 15 and roll on them. The tapered rollers 9 are disposed between the raceways 13 and 17 and roll on them. The inner ring 5 is thus rotatably supported with respect to the outer ring 3.

[0030] On the outer ring 3 a radial projection 21 is provided into which holes 23 are introduced. The outer ring 3 can be connected to a motor vehicle using the projection 21. The inner ring 5 includes a formation 25 spaced axially from the tapered rollers 7; the formation 25 includes holes 27 to which a wheel unit of a vehicle can be attached. In FIG. 1 a screw 29 is indicated.

[0031] In comparison to known embodiments, the inner ring 5 is manufactured from one piece, so that no separate raceway element is required for the tapered rollers 9. For reducing the total weight of the wheel bearing 1, the inner ring 5 is embodied as thin as possible, thus it includes a relatively large, radially inner-lying cavity 31 that expands in a funnel-shaped manner in the axial course. In the cavity 31 two support elements 33 and 35 are disposed that are disposed below the raceways 13 and 17 such that the inner ring 5 is supported in the region of the raceways 13 and 17, where the load abuts via the tapered rollers 7 or 9. The support elements 33 and 35 are radially outwardly tapered in a manner corresponding to the contour of the inner ring 5. They include radially inner-lying recesses 37 and 39, into which a shaft end of a drive shall can be introduced and releasably connected to the inner ring by a nut. The shaft end can also include a shoulder that presses against the support element 35 so that the support element 35 is pressed against the inner ring 5. The inner ring 5 includes an axially outer-lying toothing 41 that can be brought into connection with a corresponding counterpart of the drive shaft. The inner ring 5 can thus be set into rotation. Alternatively a radial toothing can be introduced in the support element 33 and/or 35.

[0032] Alternatively the support element 35 can be a component of the shall end, i.e., fixedly connected to the shaft end or formed therefrom. A toothing can also be introduced radially outward into the shaft and be correspondingly formed in the support element 35 or in the inner ring 5.

[0033] Due to the design of the outer ring 3 and of the inner ring 5, the power density of the wheel bearing 1 can be significantly increased in comparison to known designs. The wheel bearing 1 is particularly compact, i.e., in particular axially short, since relatively few components are used. The outer ring 3 and the inner ring 5 can be embodied as forged parts that are or are shaped so that no machining methods need to be used for manufacturing. Consequently the material yield is also optimized.

[0034] The outer ring 3 includes a flange 51 on which the tapered rollers 7 are guided. The tapered rollers 7 are also guided by a cage 53. Between the outer ring 3 and the inner ring 5, a seal 55, only schematically depicted here, is disposed in the region of the tapered rollers 7.

[0035] FIG. 2 is an enlarged version of the broken line rectangle region II in FIG. 1 to show details.

[0036] In the region of the tapered rollers 9, the outer ring 3 includes an axial, radially encircling projection 57 that forms a radial shoulder 59 at the end of the raceway 13. At the shoulder 59 there is a retaining ring 61 that includes a slip surface 63 for the tapered rollers 9. The retaining ring 61 is axially held between the shoulder 59 and a projection 65 so that it is pressed axially against the shoulder 59. The tapered rollers 9 are guided by a cage 67. Between the outer ring 3 and the inner ring 5, a seal 69 is held in the region of the projection 57.

[0037] The retaining ring 61 can be embodied, for example, from steel or a sintered material including introduced lubricant. The contact between the tapered rollers 9 and the slip surface 63 can thus be optimized with respect to friction. The slip surface 63 is also embodied in a manner corresponding to the course of the abutting end side of the tapered rollers 9, in the present exemplary embodiment thus obliquely with respect to the axial or radial direction.

[0038] For the assembly of the wheel bearing 1, the outer ring 3 and the tapered rollers 7 are first brought together with the cage 53 and the seal 55, as with known embodiments. The tapered rollers 9 are then brought into the space formed between outer ring 3 and inner ring 5, and the cage 67 is inserted. For this purpose the cage 67 is interrupted a point of its circumference so that the cage 67 can be expanded in order to fit over the corresponding end of the inner ring 5.

[0039] According to the manufacturing tolerances of the components, the axially outer end side of the tapered rollers 9 has a different-sized offset with respect to the shoulder 59 with each wheel bearing 1. The end side will thus, for example, project axially past the shoulder 59 by a few micrometers; this will be more or fewer micrometers depending on the manufacturing tolerance. Alternatively the end side can also lie more or less behind the shoulder. The offset is determined during assembly by measuring, after the tapered rollers 9 have been inserted and the bearing has been rolled-on. In accordance with the measurement result, the retaining ring 61, is, for example, finished by machining, so that on the one hand it abuts axially against the shoulder 59, and on the other hand the tapered rollers 9 can slip against the slip surface 63 with defined preload. Alternatively and depending on the application a defined bearing clearance can also be set. A complex pairing of the tapered rollers and the rings can be omitted.

[0040] Thus it can be necessary, for example, to remove more or less material from the retaining ring 61 in the region of the slip surface 63, when the tapered rollers 9 project axially beyond the shoulder 59. It can also be necessary to remove material in the region of the retaining ring 61 that abuts against the shoulder 59, when the shoulder 59 projects axially beyond the end side of the tapered rollers 9.

[0041] The retaining ring 61 is then inserted. At this point in time in the assembly the projection 65 is not yet present; it is only generated after the insertion of the retaining ring 61 by staking. Alternatively the retaining ring 61 can also be connected to the outer ring 3 by adhering, welding, screwing, or soldering. Finally the seal is inserted.

[0042] Alternatively the retaining ring 61 can also be held on the inner ring 5.

[0043] Due to the use of a retaining ring 61, both the outer ring 3 and the inner ring 5 can be embodied one-piece, i.e., the raceways 11 to 17 are formed in the outer ring 3 or in the inner ring 5. Neither the outer ring 3 nor the inner ring 5 need to be embodied split. Thus no separate raceway elements are required.

[0044] Due to the use of tapered rollers 7 and 9 in both rows of rolling elements the wheel bearing is particularly loadable and can be used, for example, for trucks.

[0045] In FIG. 3, a wheel bearing 101 is depicted as a further embodiment of the disclosure. It is embodied largely identical to the wheel bearing 1 of FIG. 1, wherein the reference numbers have been adopted. In the following the differently embodied parts will primarily be discussed. Thus the wheel bearing 101 includes a row of balls 107 instead of the tapered rollers 7. Accordingly raceways 111 and 115 are formed in the outer ring 103 or inner ring 105. In comparison to the embodiment of FIG. 1, the inner ring 105 is formed thicker in the region of the raceway 115, so that no support element is required and the inner ring 105 can support loads required for use. The inner ring 105 includes an abutment surface 121 for the abutment of the nut of the shaft end of the drive shaft. The wheel bearing 101 can be used, for example, for automobiles or light commercial vehicles.

[0046] A correspondingly thicker-embodied inner ring in the region of the left raceway can also be provided when the left row of rolling elements is embodied as tapered rollers. Thus with a slightly modified embodiment of FIG. 1, the support element 35 could also be omitted.

[0047] In further exemplary embodiments numerous details can be optimized, such as, for example, the material thickness of the inner ring and the axial distance between the rolling elements regions. Thus a wheel bearing can be provided that is as compact as possible, weight-optimized, simple to manufacture, and configurable for various purposes and loads.

[0048] Instead of the tapered rollers 7 and 9, other types of rollers, such as, for example, obliquely disposed cylindrical rollers, can also be used.

[0049] In FIG. 4 a method according to a preferred embodiment of the disclosure is schematically depicted.

[0050] In a first method step 501 the outer ring 3 or 103, the inner ring 5 or 105, and the rolling elements are manufactured. In a second method step 503 the first of the rows of rolling elements is introduced into the outer ring 3 or 103 and held by a cage. In a third method step 505 the inner ring 5 or 105 is introduced into the outer ring 3 or 103 so that first row of rolling elements, i.e., the tapered rollers 7 or the halls 107, is contacted by the corresponding raceways 11 and 15 or 111 and 115. In a fourth method step 507 the tapered rollers 9 are between the outer ring 3 or 103 and the inner ring 5 or 105 such that they are contacted by the raceways 13 and 17. The cage 67 is also inserted.

[0051] In a fifth method step 509 the spacing of an outer end side of the tapered rollers 7 and the shoulder 59 is first measured. Here the minimum distance is preferably measured. In a sixth method step 511, in a manner depending on the measured distance the retaining ring 61 is processed so that with the later abutting of the retaining ring 61 against shoulder 59 the end sides of the tapered rollers 9 are acted upon by the slip surface 63 with a predetermined contact force. Thus the preload or the bearing clearance of the bearing is set. Depending on the measured distance, the processing of the retaining ring 61 can be a machining, wherein material is removed from the retaining ring 61 in the region where the slip surface 63 lies. This occurs in the cases when the end side of the tapered roller 9 projects axially over the shoulder 59 as is depicted in FIG. 2. Here the amount of material to be removed is measured at the measured distance and the preload or the bearing clearance to be set.

[0052] In a seventh method step 513 the retaining ring 61 is inserted so that it abuts against shoulder 59, and the slip surface 63 exerts the previously specified force on the tapered rollers 9. For this purpose the retaining ring 61 can be pressed against the shoulder 59 using a tool. The projection 65 is then generated by staking or similar, so that the retaining ring 61 is held on the shoulder 59.

[0053] 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 bearing assemblies.

[0054] 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.

[0055] 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.