FIELD
The present invention relates to the field of automotive engineering. In particular, the invention relates to high capacity 3rd generation wheel hub bearing assemblies.
DEFINITIONS
Hub inner: A rotating inner portion of a hub bearing assembly having an integrated flange for mounting wheel on it.
An extended portion on the hub inner provides space for fitting of a second inner while the remaining portion is formed as a flange over the second inner, thus locking the bearing assembly.
Hub outer: Refers to a stationary outer portion of a hub bearing assembly enclosing the hub inner and having an integrated flange for mounting over a vehicle frame.
Outboard seal: A seal pressed into a seal groove of the hub outer, outwards, towards road/wheel direction.
Inboard seal: Seal mounted on the hub outer in a direction opposite to the outboard seal. Depending on the application, this can be replaced with an end cap.
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BACKGROUND
A hub bearing is an automotive part used in most cars, passenger vehicles and light and heavy trucks. It is located between the brake drums or discs and the drive axle.
Conventionally, hub assemblies use standard single row ball or tapered roller bearings assembled in pairs, also referred to as ‘Generation 0’ hub assemblies. With evolution, hub bearings now incorporate several functions.
Improved design and technologies have led to the creation of specific bearings, with features optimized for ease of assembly. For example, in ‘Generation 1’ hub bearings, bearing preload is integrated into the production process. Also, a bearing is pre-lubricated and sealed. Likewise, ‘Generation 2’ hub bearings are provided with single flanged bearings with an integrated hub function and flanged bearings with an integrated stub axle fixing. The most recent are ‘Generation 3’ hub bearings, which are provided with double flanged bearing integrating hub and flange functions for ease of assembly and weight reduction.
A typical 3rd Generation hub bearing 100 is illustrated in Figure 1. As shown, the typical, 3rd Generation hub bearing 100 includes the following components: a hub inner 105, a second inner 110, ball-cage assemblies 115, a hub outer 120, an inboard seal or end cap 125, an outboard seal 130, and hub bolt(s) 135. A ball-cage assembly 115 includes
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balls placed into pockets provided in cages. To assemble the hub bearing 100, two such ball-cage assemblies 115 are mounted on raceways (not shown) provided on the hub outer 120 and grease is applied on the balls in required quantity. Subsequently, the outboard seal 130 is mounted on the hub outer 120. Further, the hub bolts 135 are press fitted on the hub inner 105. The hub inner 105 with the bolts 140 is inserted in the hub outer 120 from the side of the outboard seal 130, and the second inner 110 is inserted in the hub outer 120 from the other side resting on an outer diameter of an extended portion of the hub inner 105. During the assembling, axial clearance is checked and maintained as per requirement. The extended portion of the hub inner 105 is formed by an orbital forming process in the shape of a flange 140 over the second inner 110, thus locking the complete arrangement. Finally, the inboard seal or end cap 125 is mounted on the hub outer 120 as per design requirement.
It is observed that the existing Generation 3, or 3rd Generation, hub bearings, are not suitable for high capacity installations or where the requirement is to take care of additional radial loads that the hub bearings are subjected to. Accordingly, there is a need to improve the construction of Generaton-3 hub bearings so that they can prove useful in high radial load applications.
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OBJECTS Some of the objects of the present invention are aimed to ameliorate one or more problems of the prior art or to at least provide a useful alternative and are listed herein below.
An object of the present invention is to provide a hub bearing that has a long life in high load conditions.
Another object of the present invention is to provide a 3rd Generation hub bearing that is capable of bearing additional radial loads without compromising the axial load carrying capacity.
One more object of the present invention is to provide a high capacity 3rd Generation hub bearing that is simpler in construction and cost effective.
An object of the present invention is to provide high load capacity in existing 3rd Generation hub bearings without much modification.
Other objects and advantages of the present invention will be more apparent from the following description when read in conjunction with the accompanying figure, which are not intended to limit the scope of the present disclosure.
SUMMARY
Described herein is a high capacity 3rd generation hub bearing assembly comprising a pair of ball-cage assemblies mounted on a hub outer
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at a distance from each other, an outboard seal mounted on the hub outer, a hub inner having an extended portion, the hub inner inserted in the hub outer from a side of the outboard seal, a second inner inserted in the hub outer from a side resting on an outer diameter of the extended portion of the hub inner, and an inboard seal mounted on the hub outer, wherein a cylindrical roller cage assembly is disposed on the hub outer, in a space between the pair of ball-cage assemblies.
In an embodiment, hub bolts are press fitted on the hub inner before the hub inner is inserted into the hub outer.
In an embodiment, balls of the ball-cage assemblies and cylindrical rollers of the cylindrical roller cage assembly are greased prior to assembly.
In an embodiment, a pre-determined amount of clearance is maintained between the cylindrical roller cage assembly and each of the ball-cage assemblies.
In an embodiment, the extended portion of the hub inner is formed in the shape of a flange over the second inner.
In an embodiment, alternatively external threads are provided on the extended portion of hub inner to facilitate mounting of a nut.
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BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
A high capacity, 3rd generation hub bearing assembly of the present disclosure will now be described with the help of accompanying drawings, in which:
Figure 1 illustrates a cross-sectional view of a conventional 3rd generation hub bearing;
Figure 2 illustrates a cross-sectional view of a high capacity, 3rd generation hub bearing assembly, in accordance with an embodiment of the present disclosure;
Figure 3 illustrates an isometric view of a cylindrical roller cage assembly in with an embodiment of the present disclosure; and
Figure 4 illustrates a cross-sectional view of a hub outer in accordance with an embodiment of the present disclosure.
DETAILED DESCRIPTION
A high capacity 3rd generation hub bearing assembly of the present disclosure will now be described with reference to the accompanying embodiments which do not limit the scope and ambit of the disclosure. The description provided is purely by way of example and illustration.
The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the following description. Descriptions of well-known components and
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processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
The description of the specific embodiments that follows will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
With regard to Figures 2 to 4, a high capacity 3rd Generation hub bearing assembly 200 and its components are illustrated, in accordance with an embodiment of the present disclosure. The high capacity 3rd generation hub bearing 200, hereinafter referred to as hub bearing 200, is configured to
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withstand high radial loads and can be used in high load bearing applications. In an embodiment, the hub bearing 200 includes the following components: a hub inner 105, a second inner 110, ball-cage assemblies 115, cylindrical roller cage assembly 205, a hub outer 210, an inboard seal or end cap 125, an outboard seal 130, and hub bolt(s) 135. The ball-cage assemblies 115 are similar to the one described in relation to Figure 1 earlier, with balls pocketed into cages. To assemble the hub bearing 200, in an embodiment as shown, the cylindrical roller cage assembly 205 is mounted on the hub outer 210 in between two such ball-cage assemblies 115. The cylindrical roller cage assembly 205 comprises cylindrical rollers 207 pocketed in a cylindrical cage 203, as shown in Figure 3. Grease is applied on the balls of the ball-cage assemblies 115 and cylindrical rollers 207 of the cylindrical roller cage assembly 205 in required quantity. Subsequently, the outboard seal 130 is mounted on the hub outer 210. Further, the hub bolts 135 are press fitted on the hub inner 105. The hub inner 105 with the bolts 140 is then inserted in the hub outer 210 from the side of the outboard seal 130, and the second inner 110 is inserted in the hub outer 210 from the other side resting on an outer diameter of an extended portion of the hub inner 105. During the assembling, axial clearance is checked and maintained as per requirement. The extended portion of the hub inner 105 is formed by orbital forming process in the shape of a flange 140 over the second inner 110, thus locking the complete arrangement.
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Alternatively, a nut may also be used for fastening and retaining the second inner 110 on the hub inner 105, where external threads on the extended portion of hub inner 105 facilitate mounting of the nut. Finally, the inboard seal or end cap 125 is mounted on the hub outer 210 as per design requirement.
An additional row of cylindrical rollers of the cylindrical roller cage assembly 205 provides for the high load carrying capacity in this improved high capacity 3rd Generation hub bearing 200, within the same envelope.
The hub outer 210 is designed in such a way that it can hold one or more rows of cylindrical roller cage assembly 205 between two rows of the ball cage assemblies 115, thereby enabling the hub assembly 200 to withstand higher radial loads. For example, as shown in Figure 4, a raceway 213 is provided for the cylindrical roller cage assembly 205 in between two raceways 217 for the ball-cage assemblies 115. In different embodiments, the ball cage assemblies 115 may or may not be having the flange depending upon the fitment requirements.
In sum, the unused space in existing 3rd Generation hub bearings, such as the hub bearing 100, is now efficiently utilized by introducing an additional row of cylindrical rollers, thereby upgrading a normal 3rd Generation hub bearing 100 to a high capacity, 3rd Generation hub bearing 200.
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Throughout this specification the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
The use of the expression “at least” or “at least one” suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.
Any discussion of documents, acts, materials, devices, articles or the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
While considerable emphasis has been placed herein on the components and component parts of the preferred embodiments, it will be
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appreciated that many embodiments can be made and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other changes in the preferred embodiment as well as other embodiments of the disclosure will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.
TECHNICAL ADVANCEMENTS AND ECONOMIC SIGNIFICANCE
The technical advancements offered by the high capacity, 3rd generation hub bearing assembly of the present disclosure include the realization of:
 Increase in radial load bearing capacity of existing 3rd generation hub bearings.
 Increase in moment stiffness of existing 3rd generation hub bearings.
 Minimal modification of the hub outer to facilitate insertion of an additional row of cylindrical rollers that provides the hub bearing its high load capacity.
 Cost efficient way of upgrading existing 3rd generation hub bearings to high capacity hub bearings.

WE CLAIM:
1. A high capacity 3rd generation hub bearing assembly (200) comprising:
a pair of ball-cage assemblies (115) mounted on a hub outer (210) at a distance from each other;
an outboard seal (130) mounted on the hub outer (210);
a hub inner (105) having an extended portion, the hub inner (105) inserted in the hub outer (210) from a side of the outboard seal (130);
a second inner (110) inserted in the hub outer (210) from a side resting on an outer diameter of the extended portion of the hub inner (105); and
an inboard seal (125) mounted on the hub outer (210), wherein a cylindrical roller cage assembly (205) is disposed on the hub outer (210), in a space between the pair of ball-cage assemblies (115).
2. The hub bearing assembly (200) as claimed in claim 1, wherein hub bolts (135) are press fitted on the hub inner (105) before the hub inner is inserted into the hub outer (210).
3. The hub bearing assembly (200) as claimed in claim 1, wherein balls of the ball-cage assemblies (115) and cylindrical rollers of the cylindrical roller cage assembly (205) are greased prior to assembly.
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4. The hub bearing assembly (200) as claimed in claim 1, wherein a pre-