Vehicle wheel bearing having lightweight wheel hub

Abstract

According to one embodiment of the present invention, the provided vehicle wheel bearing enables the wheel of a vehicle to be rotatably mounted on a vehicle body and supported. The vehicle wheel bearing according to one embodiment of the present invention may comprise: a wheel hub having a wheel-mounted flange; an inner ring mounted on the wheel hub; an outer ring mounted on and fixed to a chassis member of a vehicle; and a plurality of rolling elements for supporting the wheel hub and the inner ring to be rotatable relative to the outer ring. According to one embodiment of the present invention, the wheel hub can include: an inner hub part positioned at a vehicle body side; and an outer hub part positioned at a wheel side. According to one embodiment of the present invention, the inner hub part can include a cylindrical part extending in the axial direction, and a flange part extending radially outward from the cylindrical part, and the outer hub part can include an axial end face cover part that entirely or partially covers the outer axial end face of the flange part, and an outer peripheral cover part that partially covers the outer peripheral surface of the flange part. According to one embodiment of the present invention, the inner axial end of the outer peripheral cover part can be positioned axially outward relative to the inner axial end face of the flange part.

Description

Wheel bearings for vehicles with lightweight wheel hubs

[0001] The present invention relates to a vehicle wheel bearing that supports a vehicle wheel by rotatably mounting it on a vehicle body, and more specifically, to a vehicle wheel bearing having a wheel hub manufactured to be lightweight by combining different materials.

[0002] A wheel bearing is a device that supports a vehicle's wheel by rotatably mounting it on the vehicle body. It can be divided into a wheel bearing for a driving wheel mounted on the vehicle's driving wheel and a wheel bearing for a driven wheel mounted on the vehicle's driven wheel.

[0003] For example, a wheel bearing may be configured such that a rotating element (e.g., a wheel hub and an inner ring) on ​​which a wheel of a vehicle is mounted is connected to a non-rotating element (e.g., an outer ring) that is fixed to the vehicle body through a rolling element to rotatably support the wheel of the vehicle relative to the vehicle body.

[0004] However, since these wheel bearings account for a significant portion of the vehicle's drivetrain, various studies are being conducted in the automotive industry to reduce the weight of wheel bearings.

[0005] In particular, the wheel hub is a component that accounts for a large proportion of the weight of the wheel bearing, and many attempts are being made to reduce the weight of the wheel hub to make the wheel bearing lighter.

[0006] For example, in the field of wheel bearings, a technology is being proposed to reduce the weight of the wheel hub by forming part of the wheel hub out of lightweight metal or carbon fiber reinforced plastic (CFRP).

[0007] The present invention relates to a vehicle wheel bearing having a wheel hub manufactured to be lightweight by combining different materials, and aims to provide a vehicle wheel bearing having an improved structure of the wheel hub so as to prevent different materials from being processed together when processing the cross-section of a wheel mounting flange of the wheel hub.

[0008] A representative configuration of the present invention to achieve the aforementioned purpose is as follows.

[0009] According to one embodiment of the present invention, a vehicle wheel bearing that supports a wheel of a vehicle by being rotatably mounted on a vehicle body may be provided. The vehicle wheel bearing according to one embodiment of the present invention may include: a wheel hub having a wheel mounting flange; an inner ring mounted on the wheel hub; an outer ring mounted and fixed to a chassis member of the vehicle; and a plurality of rolling elements that support the wheel hub and the inner ring so as to be rotatably relative to the outer ring. According to one embodiment of the present invention, the wheel hub may include an inner hub portion located on the vehicle body side and an outer hub portion located on the wheel side. According to one embodiment of the present invention, the inner hub portion may include a cylindrical portion extending in an axial direction and a flange portion formed by extending radially outward from the cylindrical portion, and the outer hub portion may include an axial cross-section cover portion that completely or partially covers an outer axial cross-section of the flange portion and an outer circumferential cover portion that partially covers an outer peripheral surface of the flange portion. According to one embodiment of the present invention, the inner axial end of the outer cover portion may be configured to be positioned axially outer compared to the inner axial cross section of the flange portion.

[0010] According to one embodiment of the present invention, the inner axial cross-section of the flange portion can be configured to be machined in a state where the outer hub portion is integrally formed with the inner hub portion.

[0011] According to one embodiment of the present invention, the outer cover portion may be configured so as not to be machined when machining the inner axial cross-section of the flange portion.

[0012] According to one embodiment of the present invention, the outer surface of the flange portion may be provided with a stepped portion so that the diameter of the inner axial portion becomes smaller than that of the outer axial portion.

[0013] According to one embodiment of the present invention, the outer cover portion may be provided with a catch portion that protrudes radially inward and is catchable and connected to the step portion.

[0014] According to one embodiment of the present invention, the flange portion may include a first flange portion formed by extending radially outward along a virtual extension reference line; and a second flange portion formed by extending radially outward between the circumferences of the first flange portion; and an outer surface of the second flange portion may be configured to be positioned radially inward compared to an outer surface of the first flange portion.

[0015] According to one embodiment of the present invention, the first flange portion may be provided with a fastening hole into which a wheel mounting bolt is inserted.

[0016] According to one embodiment of the present invention, the outer hub portion may further include a connecting portion positioned in a space between the circumferential directions of the first flange portions and connecting the circumferentially adjacent first flange portions.

[0017] According to one embodiment of the present invention, the outer hub portion may be formed of a lighter material than the inner hub portion.

[0018] According to one embodiment of the present invention, the inner hub portion may be formed of a steel material.

[0019] According to one embodiment of the present invention, the outer hub portion may be formed of an aluminum material.

[0020] According to one embodiment of the present invention, the outer hub portion can be integrally formed with the inner hub portion through a forging process while the inner hub portion is placed within a mold.

[0021] According to one embodiment of the present invention, the inner hub portion may have a recess sunken in the inner axial direction in the outer axial cross section.

[0022] According to one embodiment of the present invention, the outer hub portion may have a protrusion that is inserted into and engaged within the recess.

[0023] According to one embodiment of the present invention, the outer hub portion may further include a pilot portion formed by extending in the outer axial direction from the axial cross-section cover portion.

[0024] In addition, the vehicle wheel bearing according to the present invention may further include other additional components within a range that does not impair the technical idea of ​​the present invention.

[0025] A wheel bearing for a vehicle according to one embodiment of the present invention is configured such that a portion of the wheel hub is formed of a lightweight material, thereby reducing the weight of the wheel hub and the wheel bearing including the same.

[0026] In addition, the wheel bearing according to one embodiment of the present invention is configured so that the outer hub portion does not protrude axially inwardly compared to the inner axial end of the wheel mounting flange, thereby preventing different materials from being machined together when machining the inner axial cross-section of the wheel mounting flange, thereby preventing problems such as increased machining time, decreased tool life, and deterioration of machined surface quality due to simultaneous machining of different materials.

[0027] FIG. 1 exemplarily illustrates the overall structure of a vehicle wheel bearing according to one embodiment of the present invention.

[0028] FIG. 2 illustrates an example of a cross-sectional structure of a vehicle wheel bearing according to one embodiment of the present invention.

[0029] FIG. 3 illustrates a wheel hub of a vehicle wheel bearing according to one embodiment of the present invention.

[0030] FIG. 4 illustrates an example of a cross-sectional structure of a wheel hub of a vehicle wheel bearing according to one embodiment of the present invention.

[0031] FIG. 5 illustrates an inner hub portion constituting a wheel hub in a vehicle wheel bearing according to one embodiment of the present invention.

[0032] FIG. 6 illustrates an outer hub portion constituting a wheel hub in a vehicle wheel bearing according to one embodiment of the present invention.

[0033] <Explanation of symbols>

[0034] 100: Wheel bearings

[0035] 200: Wheel hub

[0036] 300: Inner hub

[0037] 310: Cylinder

[0038] 320: Flange section

[0039] 330: Step section

[0040] 340: Recess

[0041] 400: Outer hub

[0042] 410: Axial cross-section cover

[0043] 420: Outsourced Cover Department

[0044] 430: Hook

[0045] 440: Connection

[0046] 450: Protrusion

[0047] 460: Pilot Department

[0048] 500: Inner ring

[0049] 600: Outer ring

[0050] 700: Electric body

[0051] The embodiments described below are provided for the purpose of explaining the technical idea of ​​the present invention, and the scope of the present invention is not limited to the embodiments presented below or the specific description thereof.

[0052] All technical and scientific terms used in this specification have the meaning commonly understood by a person of ordinary skill in the art to which the present invention pertains unless otherwise defined, and all terms used in this specification have been selected for the purpose of more clearly explaining the present invention and have not been selected to limit the scope of the rights of the present invention.

[0053] As used herein, expressions such as “including,” “comprising,” “having,” etc. should be understood as open-ended terms implying the possibility of including other embodiments, unless otherwise stated in the phrase or sentence in which the expression is included.

[0054] In this specification, “axial” means a direction extending along the rotational center axis of the wheel bearing (“axially inward” means a direction toward the body side, and “axially outward” means a direction toward the wheel side), “radially” means a direction away from or closer to the rotational center axis perpendicular to the “axial direction,” and “circumferential” means a rotational direction centered on the aforementioned “axial direction.”

[0055] Where a component is described herein as extending axially or radially, it should be understood that this may include extending not only parallel to the axial or radial direction, but also obliquely to the axial or radial direction, unless otherwise stated in the phrase or sentence containing the expression.

[0056] The singular forms used in this specification may include plural meanings unless otherwise stated, and the same applies to the singular forms used in the claims.

[0057] When a component is referred to herein as being “positioned” or “formed” on one side of another component, it should be understood that the component is positioned or formed in direct contact with one side of the other component, or may be positioned or formed with another new component interposed therebetween.

[0058] Hereinafter, with reference to the attached drawings, preferred embodiments of the present invention will be described in detail to a degree that those skilled in the art can easily practice the present invention. In the attached drawings, identical or corresponding components are indicated by the same reference numerals, and in the description of the embodiments below, redundant description of identical or corresponding components may be omitted. However, even if a description of a specific component is omitted in the description below, this is not intended to mean that such component is not included in the corresponding embodiment.

[0059] Referring to FIGS. 1 and 2, a vehicle wheel bearing according to one embodiment of the present invention is exemplarily illustrated. The vehicle wheel bearing according to one embodiment of the present invention can be formed with a structure generally similar to that of a conventional vehicle wheel bearing, and as described below, has a basic feature in that the wheel hub is formed with a lightweight structure by combining different materials.

[0060] Specifically, a vehicle wheel bearing (100) according to one embodiment of the present invention may be configured to perform a function of supporting a wheel of a vehicle rotatably relative to a vehicle body by connecting a rotating element (e.g., wheel hub (200) and inner ring (500)) to a non-rotating element (e.g., outer ring (600)) through a rolling element (700) as illustrated in the drawing.

[0061] According to one embodiment of the present invention, the wheel hub (200) may be formed in a substantially cylindrical structure extending in the axial direction, and a wheel mounting flange (hub flange) may be provided on one outer peripheral surface of the wheel hub (200). The wheel mounting flange is formed in a shape extending radially outward from the outer peripheral surface of the wheel hub (200) and may be used to mount a wheel of a vehicle to the wheel hub (200) using a hub bolt or the like. Meanwhile, the wheel hub (200) may be configured to have an inner ring (500) mounted on the body-side end, and a rolling element raceway (inner raceway) may be formed on a portion of the outer peripheral surface of the wheel hub (200) to support the rolling element (700) from the radially inner side.

[0062] According to one embodiment of the present invention, the inner ring (500) may be configured to be mounted on the outer surface of the wheel hub (200) at least once, and the outer surface of the inner ring (500) may be configured to have a raceway surface (inner raceway surface) of a rolling element formed thereon to support the rolling element (700) from the radially inner side. For example, the inner ring (500) may be configured to be mounted and coupled to a mounting portion provided near the body-side end of the wheel hub (200), and may be configured to be fixed on the wheel hub (200) while a predetermined preload is applied.

[0063] According to one embodiment of the present invention, the outer ring (600) may be configured to have a body-side mounting flange on the outer circumference used to mount the wheel bearing on the body, and to have a raceway surface on the inner circumference with which the rolling element (700) comes into contact. The raceway surface (outer raceway surface) formed on the inner circumference of the outer ring (600) may be configured to cooperate with the raceway surface (inner raceway surface) formed on the wheel hub (200) and / or the inner ring (500) to accommodate and support the rolling element (700), which is a rolling element, between these raceway surfaces.

[0064] According to one embodiment of the present invention, the electric body (700) is interposed between a rotating element of a wheel bearing (100) [e.g., wheel hub (200) and / or inner ring (500)] and a non-rotating element [e.g., outer ring (600)], and can perform a function of supporting the rotating element of the wheel bearing (100) so as to be able to rotate relative to the non-rotating element.

[0065] However, the above-described configurations of the vehicle wheel bearing (100) according to one embodiment of the present invention are not limited to the structure shown in the drawing, and may be modified and formed into various structures applicable to the vehicle wheel bearing.

[0066] For example, in the case of the embodiment shown in the drawing, the vehicle wheel bearing (100) is configured in a form in which one side of the track surface for supporting the rolling element (700) is directly formed on the outer surface of the wheel hub (200), but the vehicle wheel bearing (100) according to one embodiment of the present invention may be implemented by modifying it into another structure, such as by mounting two inner rings (500) on the wheel hub (200) to support the rolling element (700) through the two inner rings (500).

[0067] In addition, in the case of the embodiment illustrated in the drawing, the vehicle wheel bearing (100) according to one embodiment of the present invention is illustrated as a wheel bearing for a driving wheel in which a constant velocity joint is coupled to a wheel hub (200), but the vehicle wheel bearing (100) according to one embodiment of the present invention may also be formed as a wheel bearing for a driven wheel.

[0068] According to one embodiment of the present invention, the wheel hub (200) may be configured to include an inner hub portion (300) located on the body side and an outer hub portion (400) located on the wheel side, and the inner hub portion (300) and the outer hub portion (400) may be configured to be formed of different materials.

[0069] For example, according to one embodiment of the present invention, the inner hub portion (300) may be configured to be formed of a steel material (e.g., carbon steel) similar to a wheel bearing for a conventional vehicle, and the outer hub portion (400) may be configured to be formed of a material that is lighter than the inner hub portion (300) (e.g., aluminum material, etc.).

[0070] According to one embodiment of the present invention, the inner hub portion (300) and the outer hub portion (400) can be configured to be manufactured through a forging process to form a wheel hub (200).

[0071] According to one embodiment of the present invention, the wheel hub (200) may be configured to first form an inner hub portion (300) with a steel material (for example, the inner hub portion (300) may be formed through a hot forging process), and then, while the inner hub portion (300) is placed in a mold, a lightweight material (for example, aluminum material) is injected into the mold to form an outer hub portion (400) by hot forming in a high temperature and high pressure environment.

[0072] According to one embodiment of the present invention, the inner hub portion (300) may be configured to include a cylindrical portion (310) extending axially and a flange portion (320) formed by extending radially outward from the cylindrical portion (310).

[0073] According to one embodiment of the present invention, the outer hub portion (400) may include an axial cross-section cover portion (410) that completely or partially covers the outer axial cross-section of the flange portion (320) and an outer circumferential cover portion (420) that partially covers the outer peripheral surface of the flange portion (320).

[0074] According to one embodiment of the present invention, the outer cover portion (420) of the outer hub portion (400) is configured such that the inner axial end (422) is positioned axially outerward compared to the inner axial end surface (322) of the flange portion (320), so that when the inner axial end surface (322) of the flange portion (320) of the inner hub portion (300) is machined, the outer cover portion (420) can be configured not to be machined.

[0075] Specifically, the wheel hub (200) of the vehicle wheel bearing (100) according to one embodiment of the present invention may be configured to integrally form an outer hub portion (400) with an inner hub portion (300) and then machine-process the inner axial end face (322) of the flange portion (320) to form a mounting surface for a wheel mounting bolt. Since the outer cover portion (420) has a structure that does not protrude axially inward compared to the inner axial end face (322) of the flange portion (320), the outer cover portion (420) of the outer hub portion (400) may be configured not to be machine-processed when the inner axial end face (322) of the flange portion (320) is machined.

[0076] According to this configuration, when machining the inner axial cross-section (322) of the flange portion (320), the inner hub portion (300) and the outer hub portion (400) formed of different materials are prevented from being processed together, thereby preventing problems such as a decrease in machinability and / or a decrease in machining quality due to simultaneous machining of different materials.

[0077] According to one embodiment of the present invention, the outer surface of the flange portion (320) may be provided with a stepped portion (330) that makes the diameter of the inner axial portion smaller than that of the outer axial portion.

[0078] According to one embodiment of the present invention, the outer circumferential cover portion (420) of the outer hub portion (400) may be configured to cover the outer circumferential surface of the flange portion (320) with the exception of a portion of the axial inner portion, and the outer circumferential surface of the step portion (330) may be configured to be at least partially covered by the outer circumferential cover portion (420).

[0079] According to one embodiment of the present invention, the outer cover portion (430) of the outer hub portion (400) may be configured to have a catch portion (430) that protrudes radially inward and is caught and connected to the step portion (330).

[0080] According to one embodiment of the present invention, the flange portion (320) of the inner hub portion (300) has a plurality of virtual extension reference lines (L s ) may include a first flange portion (320a) formed by extending radially outward along the circumference of the first flange portion (320a) and a second flange portion (320b) formed by extending radially outward between the circumferences of the first flange portion (320a). (See Fig. 5)

[0081] According to one embodiment of the present invention, the first flange portion (320a) may be provided with a fastening hole into which a wheel mounting bolt is inserted, and the second flange portion (320b) may be configured to have a smaller diameter than the first flange portion (320a) for weight reduction [i.e., the outer circumference of the second flange portion (320b) is positioned radially inward compared to the outer circumference of the first flange portion (320a).

[0082] According to one embodiment of the present invention, the axial cross-section cover portion (410) of the outer hub portion (400) may be configured to include a first axial cross-section cover portion (410a) that completely or partially covers the outer axial cross-section of the first flange portion (320a) and a second axial cross-section cover portion (410b) that completely or partially covers the outer axial cross-section of the second flange portion (320b), and the outer circumferential cover portion (420) of the outer hub portion (400) may be configured to include a first outer circumferential cover portion (420a) that partially covers the outer circumferential surface of the first flange portion (320a) and a second outer circumferential cover portion (420b) that partially covers the outer circumferential surface of the second flange portion (320b).

[0083] In addition, according to one embodiment of the present invention, the engaging portion (430) of the outer hub portion (400) may be configured to include a first engaging portion (430a) that engages with a step portion [first step portion (330a)] formed on the outer surface of the first flange portion (320a) and a second stepped portion (430b) that engages with a step portion [second step portion (330b)] formed on the outer surface of the second flange portion (320b).

[0084] According to one embodiment of the present invention, the outer hub portion (400) may be provided with a connecting portion (440) positioned in a space between the circumferential directions of the first flange portions (320a) and connecting the circumferentially adjacent first flange portions (320a).

[0085] According to one embodiment of the present invention, the connecting portion (440) may be configured to fill the space between the radially outer side of the second flange portion (320b) and the circumferential side of the first flange portion (320a) to connect adjacent first flange portions (320a).

[0086] According to one embodiment of the present invention, the inner hub portion (300) may have a recess (340) that is sunken in the inner axial direction in the outer axial cross section, and the outer hub portion (400) may have a protrusion (450) that protrudes in the axial direction so that the protrusion (450) may be configured to be inserted into and coupled to the recess (340).

[0087] According to one embodiment of the present invention, the recess (340) may be formed in various forms, such as a structure formed continuously along the circumferential direction, a structure provided in multiple forms spaced apart along the circumferential direction, or a structure in which these are combined.

[0088] For example, in the case of the embodiment shown in the drawing, the recess (340) is formed by combining a first recess (340a) formed continuously along the entire circumferential direction and a second recess (340b) formed by extending radially from the first recess (340a) and spaced apart from each other along the circumferential direction.

[0089] In addition, the protrusion (450) can be formed in a shape corresponding to the recess (340), and in the case of the embodiment shown in the drawing, the protrusion (450) is configured to have a first protrusion (450a) corresponding to the first recess (340a) and a second protrusion (450b) corresponding to the second recess (340b).

[0090] According to one embodiment of the present invention, the outer hub portion (400) may further include a pilot portion (460) formed to extend in the outer axial direction from the end cover portion (410) at the outer axial end.

[0091] According to one embodiment of the present invention, the pilot unit (460) can perform a function of assisting the assembly of the wheel by centering the wheel of the vehicle relative to the wheel hub (200) when mounting the wheel of the vehicle on the wheel hub (200).

[0092] Although the present invention has been described above with specific details such as specific components and limited examples, the above examples are provided only to help a more general understanding of the present invention, and the present invention is not limited thereto, and those with ordinary knowledge in the technical field to which the present invention pertains can make various modifications and variations based on this description.

[0093] Therefore, the idea of ​​the present invention should not be limited to the embodiments described above, and all things that are modified equally or equivalently to the claims described below as well as the claims are considered to fall within the scope of the idea of ​​the present invention.

Claims

1. A vehicle wheel bearing (100) that supports a vehicle wheel by rotatably mounting it on the vehicle body. A wheel hub (200) having a wheel mounting flange; An inner ring (500) mounted on the above wheel hub (200); An outer ring (600) mounted and fixed to a chassis member of a vehicle; It includes a plurality of electric motors (700) that support the wheel hub (200) and the inner ring (500) so as to be able to rotate relative to the outer ring (600), The above wheel hub (200) includes an inner hub part (300) located on the body side and an outer hub part (400) located on the wheel side. The inner hub portion (300) includes a cylindrical portion (310) extending axially and a flange portion (320) formed by extending radially outward from the cylindrical portion (310). The above outer hub part (400) includes an axial cross-section cover part (410) that completely or partially covers the outer axial cross-section of the flange part (320) and an outer circumferential cover part (420) that partially covers the outer peripheral surface of the flange part (320). The inner axial end (422) of the outer cover portion (420) is configured to be positioned axially outer compared to the inner axial cross-section (322) of the flange portion (320). Wheel bearings for vehicles.

2. In paragraph 1, The inner axial cross-section (322) of the above flange portion (320) is configured to be machined in a state where the outer hub portion (400) is integrally formed with the inner hub portion (300). Wheel bearings for vehicles.

3. In paragraph 2, The above outer cover part (420) is configured so that the inner axial cross-section (322) of the flange part (320) is not machined when machining. Wheel bearings for vehicles.

4. In paragraph 3, The outer surface of the above flange portion (320) is provided with a step portion (330) that makes the diameter of the inner axial portion smaller than that of the outer axial portion. Wheel bearings for vehicles.

5. In paragraph 4, The outer cover portion (420) above is provided with a catch portion (430) that protrudes radially inward and is caught and connected to the step portion (330). Wheel bearings for vehicles.

6. In paragraph 5, The above flange portion (320) is a virtual extension reference line (L s ) and a first flange portion (320a) formed by extending radially outward along the circumference of the first flange portion (320a); and a second flange portion (320b) formed by extending radially outward between the circumferences of the first flange portion (320a); The outer surface of the second flange portion (320b) is configured to be positioned radially inward compared to the outer surface of the first flange portion (320a). Wheel bearings for vehicles.

7. In paragraph 6, The first flange portion (320a) above is provided with a fastening hole into which a wheel mounting bolt is inserted. Wheel bearings for vehicles.

8. In paragraph 7, The above outer hub part (400) is located in the space between the circumferential directions of the first flange parts (320a) and further includes a connecting part (440) connecting the circumferentially adjacent first flange parts (320a). Wheel bearings for vehicles.

9. In paragraph 3, The above outer hub part (400) is formed of a lighter material than the above inner hub part (300). Wheel bearings for vehicles.

10. In paragraph 9, The inner hub portion (300) is formed of steel material. Wheel bearings for vehicles.

11. In paragraph 10, The above outer hub part (400) is formed of aluminum material. Wheel bearings for vehicles.

12. In paragraph 11, The above outer hub part (400) is formed integrally with the inner hub part (300) through a forging process while the inner hub part (300) is placed in a mold. Wheel bearings for vehicles.

13. In paragraph 12, The inner hub portion (300) has a recess (340) sunken in the inner axial direction in the outer axial cross section. Wheel bearings for vehicles.

14. In paragraph 13, The above outer hub part (400) has a protrusion (450) that is inserted and coupled into the recess (340). Wheel bearings for vehicles.

15. In paragraph 14, The above outer hub part (400) further includes a pilot part (460) formed by extending in the outer axial direction from the shaft cross-section cover part (410). Wheel bearings for vehicles.

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