Wheel bearing outer ring and / or wheel hub and method for manufacturing a wheel bearing outer ring and / or wheel hub

Abstract

The present invention is based on a wheel bearing outer ring (10) and / or hub having at least one radially external region (12). It is recommended that the internal stress in said region be greater than the stress achievable by simple cleaning spraying of that region.

Description

Technical Field

[0001] This invention relates to a wheel hub. Background Technology

[0002] A hub is known that constitutes the outer ring of a wheel bearing and has a radially external region.

[0003] The technical problem to be solved by the present invention is particularly to provide this type of hub or this type of wheel bearing outer ring with an efficient structure. Summary of the Invention

[0004] The present invention is based on a wheel bearing outer ring and / or hub with at least one radially external region.

[0005] According to the regulations, the internal stress in the area is greater than the stress achievable by simple cleaning blasting of that area. "Cleaning blasting" (or blasting cleaning) should be understood in particular as blasting performed solely for surface cleaning, wherein the blasting is preferably shot peening. The internal stress achievable by simple (or merely) cleaning blasting of the surface should be understood in particular as internal stress in the entire range greater than -80 MPa, and preferably greater than -50 MPa. "Greater than -50 MPa" internal stress should be understood in particular as internal stress between -50 MPa and 0 MPa. This allows for a highly efficient structure. In particular, it allows for the stability of the area and, more particularly, the surface of the area, and for greater resistance to crack formation. Furthermore, it allows for a smaller weight of the hub or outer ring of the bearing.

[0006] Preferably, the internal stress measured from the radially outer surface of this region to a depth of 50 μm is less than -70 MPa, more preferably less than -130 MPa, and more preferably less than -200 MPa, particularly preferably less than -300 MPa. This achieves particularly low sensitivity to crack formation.

[0007] Preferably, the internal stress measured from the radially outer surface of the region to a depth of 50 μm is greater than -5000 MPa, more preferably greater than -2000 MPa, and more preferably greater than -900 MPa, particularly preferably greater than -500 MPa. This method achieves low-cost manufacturability.

[0008] Advantageously, the wheel bearing outer ring and / or hub have a first end side and a second end side, the second end side having a flange for securing the wheel and / or wheel adapter, wherein the distance of this region relative to the first end side is less than the distance of this region relative to the second end side. This allows for the stability and crack resistance of the half of the wheel bearing outer ring or hub, which, in its final assembled state, is positioned away from the wheel mounted on the wheel bearing outer ring or hub. Particularly useful are components of trucks and, especially, three-axle semi-trailers, because the material arranged radially outside the rolling elements facing the truck or semi-trailer is subjected to high loads during shunting. This high load is here caused by a high torque formed by axial forces.

[0009] Furthermore, it is suggested that the maximum diameter of the running track, which forms part of the wheel bearing outer ring or hub and has the shortest distance to the first end side, and the maximum diameter of the axial end of the region near the first end side constitute a ratio less than 0.86, particularly less than 0.81, preferably less than 0.7, and especially preferably less than 0.6. "The running track has the shortest distance to the first end side" should be understood as meaning that the running track has a smaller distance relative to the first end side than all other tracks of the wheel bearing outer ring or hub. This allows for a smaller vehicle weight and higher available load capacity, in which the wheel bearing outer ring or hub is installed.

[0010] Preferably, the internal stress is formed at least in part by at least one rolling process and / or by inductive hardening and / or by blasting (or shot peening), thereby achieving low-cost manufacturability.

[0011] Advantageously, the region has a maximum axial length relative to the outer ring of the bearing or the hub, which is less than half the maximum axial length of the outer ring of the bearing or the hub. This confines the region to the portion of the outer ring of the bearing or the hub that is subjected to high loads during operation.

[0012] Furthermore, it is specified that the radially outward surface of the region has the shape of a truncated cone circumferential surface or a cylindrical circumferential surface. This allows for the implementation of a simple structure at low cost.

[0013] Furthermore, a method is provided for manufacturing wheel bearing outer rings and / or hubs with radially outward-facing regions, particularly the aforementioned wheel bearing outer rings and / or hubs with radially outward-facing regions, wherein the internal stress formed in said region is greater than the internal stress that could be formed by simple cleaning spraying of that region. This allows for a highly efficient structure. Preferably, the internal stress is formed by rolling and / or spraying and / or inductive hardening, thereby achieving cost-effective manufacturing of the wheel bearing outer ring or hub. Attached Figure Description

[0014] Other advantages are described in the following figures. Embodiments of the invention are illustrated in the figures. The figures and description contain a combination of numerous technical features. Those skilled in the art can also consider these technical features individually and combine them into other reasonable combinations, depending on their purpose.

[0015] Figure 1 A schematic diagram showing half of an axial cross-section through a wheel bearing having a hub is shown.

[0016] Figure 2 This shows a view of the end half of the wheel bearing. Detailed Implementation

[0017] Figure 1 A schematic diagram showing half of an axial cross-section of a wheel bearing having a hub, the hub being the outer ring 10 of the wheel bearing. The outer ring has a radially outward region 12, the internal stress of which is greater than that achievable by simple cleaning spraying through this region. This region 12 extends from its radially outward surface 14 to a depth of 100 μm. The surface has the shape of a truncated cone circumferential surface. In an alternative embodiment, surface 14 has a circumferential interruption, the interruption being due to a recess in the hub.

[0018] Furthermore, region 12 extends 360° circumferentially along the outer ring of the wheel bearing. Additionally, region 12 has a maximum axial length 21, which is equivalent to one-quarter of the maximum axial length of the outer ring of the wheel bearing. Internal stresses in region 12 exist throughout the entire region 12 and are less than -200 MPa and greater than -5000 MPa.

[0019] The hub has a flange 20 with perforations 32 designed for securing a wheel or wheel adapter with bolts. A first end side 16 is opposite the flange 20. The flange 20 is arranged on a second end side 18 of the hub. The distance of the region 12 relative to the first end side is less than the distance of the region relative to the second end side. The hub is of integral construction and has a hardened first running track 24 for rolling the rolling elements 34. The outer ring of the wheel bearing has a tough material between the region 12 and the running track 24 to prevent brittle fracture. The maximum diameter 22 of the running track 24 is proportional to the maximum diameter 26 of the axial end 28 (near the first end side of the region 12), a ratio less than 0.81. This relatively small ratio results in a smaller wall thickness of the hub along the axial length of the region 12. This smaller wall thickness is achieved due to the internal stresses applied in the region 12, which make the hub and, in particular, the region 12 robust and insensitive to crack formation. Given the relatively small wall thickness, the wheel hub has a relatively small mass, which results in lower CO2 emissions during operation, for example, when the wheel bearing is installed in a truck.

[0020] In addition, the wheel bearing also has other rolling elements 36 that roll on the running track 38 of the outer ring 10 of the wheel bearing during operation. The outer ring 10, rolling elements 36, and first inner ring 40 of the wheel bearing constitute a first tapered roller bearing. The second inner ring 42, rolling elements 34, and outer ring 10 of the wheel bearing constitute a second tapered roller bearing. The inner rings 40 and 42 are combined in a form-fitting manner by an annular member 44. Furthermore, the gap between the outer ring 10 and the inner ring of the wheel bearing is sealed on the end side by a seal.

[0021] The surface 14 can, of course, have other geometries, such as the shape of a circumferential surface of a cylinder. Furthermore, the region 12 can have other dimensions, for example, it can be deeper, such as 300 μm. Additionally, internal stress can exist outside region 12.

[0022] In manufacturing the outer ring 10 of the wheel bearing, the temporary shape of the surface 14 is first formed by turning and / or forging. Subsequently, internal stress is formed by shot peening. In other embodiments, internal stress can also be formed, in particular, by at least one rolling process or by inductive hardening.

[0023] List of reference numerals

[0024] 10 wheel bearing outer ring

[0025] 12 regions

[0026] 14 Surface

[0027] 16 end sides

[0028] 18 end sides

[0029] 20 flanges

[0030] 21 Length

[0031] 22 diameter

[0032] 24 Running track

[0033] 26 diameter

[0034] 28 end

[0035] 30 Axial

[0036] 32 perforations

[0037] 34 Rolling elements

[0038] 36 Rolling elements

[0039] 38. Running track

[0040] 40 Inner Circle

[0041] 42 Inner Circle

[0042] 44 Ring-shaped component

Claims

1. A wheel bearing outer ring (10) and / or hub having at least one radially outwardly oriented region (12), characterized in that, The internal stress in the region is greater than the internal stress that can be achieved by simple cleaning spray through the region, wherein the maximum diameter (22) of the running track (24) that becomes the outer ring of the wheel bearing or the hub and has the shortest distance to the first end side of the wheel bearing or the hub and the maximum diameter (26) of the axial end (28) of the region near the first end side constitute a ratio that is less than 0.

86.

2. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The internal stress measured from the radially outer surface (14) of the region to a depth of 50 μm is less than -70 MPa.

3. The wheel bearing outer ring and / or hub according to any one of the preceding claims, characterized in that, The internal stress measured from the radially outer surface of the region to a depth of 50 μm is greater than -5000 MPa.

4. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The outer ring of the wheel bearing and / or the hub has a first end side (16) and a second end side (18), the second end side having a flange (20) for securing the wheel and / or wheel adapter, wherein the distance of the region relative to the first end side is less than the distance of the region relative to the second end side.

5. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The ratio is less than 0.

81.

6. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The internal stress is formed at least in part through at least one rolling process and / or through inductive hardening and / or through spraying.

7. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The region has a maximum length (21) of the axial direction (30) of the reference wheel bearing outer ring or hub, which is less than half of the maximum length of the reference axial direction of the wheel bearing outer ring or hub.

8. The wheel bearing outer ring and / or hub according to claim 1, characterized in that, The radially external surface (14) of the region has the shape of a circumferential surface of a truncated cone or a circumferential surface of a cylinder.

9. A method for manufacturing a wheel bearing outer ring and / or hub according to any one of claims 1 to 8 having a radially outward region, wherein, The internal stress formed in the region is greater than the internal stress that could be formed by simple cleaning spraying in that region.

10. The method according to claim 9, wherein, The internal stress is formed by rolling and / or spraying and / or inductive hardening.

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