Creep-free and insulated bearing outer ring construction

Abstract

A vehicle bearing outer surface assembly system comprises a bearing that includes a bearing outer ring. The bearing outer ring includes an outer ring surface. At least one circumferential groove is machined into the bearing outer ring. An expansion element is accommodated in the at least one circumferential groove. A housing accommodates the bearing, which has a gap between an inner housing surface and the bearing outer ring. The expansion element expands to extend radially across the gap and come into direct contact with the inner housing surface to dampen the movement between the bearing and the inner housing surface.

Description

INTRODUCTION

[0001] The present disclosure relates to vehicle storage arrangements.

[0002] Vehicle bearing assemblies for vehicles, including but not limited to cars, trucks, vans, sport utility vehicles, autonomous vehicles, battery-powered electric vehicles, agricultural or construction equipment, rail vehicles, and the like, may include a bearing that is slidably fitted into a housing, with a sliding fit between the bearing and the housing. The sliding fit is intended to dampen rotation or movement of the bearing due to rotational forces induced, for example, by a rotating shaft passing through and rotatably supported by the bearing. Unintended movement of the bearing can lead to wear between the bearing and the housing or to misalignment of the bearing, which in turn leads to subsequent wear on a shaft passing through the bearing or wear on interconnected gears.

[0003] Electrical current, generated by induction during the operation of an electric motor, can pass through the metal-to-metal contact elements of the bearing to the housing. This can impair the bearing's function over time, potentially leading to subsequent bearing misalignment.

[0004] Although the systems and methods for mounting bearings in a housing using a sliding fit fulfill their purpose, there is therefore a need for a new and improved system and method for designing bearing surfaces. SUMMARY

[0005] From several perspectives, a vehicle bearing outer surface assembly system comprises a bearing having an outer ring. The outer ring includes an outer surface. At least one circumferential groove is machined into the outer ring. An expansion element is accommodated in this at least one circumferential groove. A housing accommodates the bearing, which has a gap between an inner housing surface and the outer ring. The expansion element expands to extend radially across the gap and come into direct contact with the inner housing surface to dampen movement between the bearing and the inner housing surface.

[0006] In another aspect of the present disclosure, the expansion element defines an elastomeric rubber.

[0007] In another aspect of the present disclosure, a fluid, which is applied either into the at least one circumferential groove prior to the installation of the expansion element or onto the expansion element during or after the insertion of the expansion element, induces a radial expansion of the expansion element in order to extend the expansion element out of the at least one circumferential groove.

[0008] In another aspect of the present disclosure, the liquid is defined as a petroleum-based liquid or a solvent-based liquid, wherein the liquid is compatible with the application environment.

[0009] In another aspect of the present disclosure, a frictional force is generated by direct contact between the expansion element and the inner surface of the housing.

[0010] In another aspect of the present disclosure, the expansion element defines an expansion foam, wherein the expansion foam is received in the at least one circumferential groove and expands to extend across the gap during the installation of the expansion foam.

[0011] In another aspect of the present disclosure, the expansion element is positioned completely within the at least one circumferential groove and is flush with, or recessed in relation to, the outer raceway surface before the expansion of the expansion element.

[0012] In another aspect of the present disclosure, the at least one circumferential groove defines a first circumferential groove and a second circumferential groove. The extension element defines a first extension element that is accommodated in the first circumferential groove and a second extension element that is accommodated in the second circumferential groove.

[0013] In another aspect of the present disclosure, a material of the expansion part comprises an impedance that attenuates an electric current passing between the bearing and the housing.

[0014] In another aspect of the present disclosure, the at least one circumferential groove defines a first circumferential groove and a second circumferential groove, wherein the first circumferential groove and the second circumferential groove individually define a common circumferential groove width.

[0015] From several perspectives, a bearing-outer-surface design system comprises a bearing that includes an outer bearing ring. At least one circumferential groove is machined into the outer bearing ring. An expansion element made of elastomeric rubber is accommodated in the at least one circumferential groove and exhibits impedance. A housing has an inner housing surface, the housing accommodating the bearing, which has a gap between the inner housing surface and the outer bearing ring. The expansion element expands to extend radially across the gap and come into direct contact with the inner housing surface to dampen the movement between the bearing and the inner housing surface. The impedance attenuates any electrical current passing between the bearing and the housing.

[0016] In another aspect of the present disclosure, the expansion element expands when it is contacted by a liquid.

[0017] In another aspect of the present disclosure, the liquid is positioned within the at least one circumferential groove before the expansion element is included.

[0018] In another aspect of the present disclosure, the liquid is applied to the expansion element after the installation of the expansion element into the at least one circumferential groove.

[0019] In another aspect of the present disclosure, the at least one circumferential groove defines a first circumferential groove and a second circumferential groove. The extension element defines a first extension element that is accommodated in the first circumferential groove and a second extension element that is accommodated in the second circumferential groove.

[0020] In another aspect of the present disclosure, the expansion element has a temperature class of at least 150 °C.

[0021] In another aspect of the present disclosure, the gap between the inner surface of the housing and the outer ring of the bearing has a nominal range of about 10 micrometers to about 20 micrometers when the bearing and the housing are at room temperature, with the gap increasing to about 30 micrometers to about 50 micrometers when the bearing and the housing are at system operating temperature.

[0022] According to several aspects, a method for constructing a bearing outer surface comprises: producing a bearing comprising a bearing outer ring having an outer ring surface; machining at least one circumferential groove into the bearing outer ring; positioning an expansion element in the at least one circumferential groove; and installing the bearing into a housing having a gap between a housing inner surface and the bearing outer ring, wherein the expansion of the expansion element is induced such that it extends radially across the gap into direct contact with the housing inner surface to dampen any movement between the bearing and the housing inner surface.

[0023] In another aspect of the present disclosure, the method comprises generating a frictional force between the outer ring surface of the bearing outer ring and the housing inner surface of the housing by partially compressing the expansion element.

[0024] In another aspect of the present disclosure, the method includes selecting a material for the expansion element to create an impedance, wherein the impedance attenuates an electric current passing between the bearing and the housing.

[0025] Further areas of application will become apparent from the description provided herein. It is understood that the description and specific examples serve only for illustration and are not intended to limit the scope of disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way. Fig. Figure 1 is a side elevation view of a bearing according to an exemplary aspect; Fig. Figure 2 is a partial cross-sectional elevation view of the bearing of Fig. 1, which is installed inside an enclosure; and Fig. Figure 3 is a partial elevation partial cross-sectional view of a modified bearing installed inside the housing. DETAILED DESCRIPTION

[0027] The following description is merely exemplary and is not intended to limit the present disclosure, application or use.

[0028] When a component, element, or layer is described as being "on" or "interacting" with another element or layer, or as being "connected" or "coupled" with the same, it may be directly on or interacting with, or connected or coupled to, the other component, element, or layer, or there may be intervening elements or layers. Conversely, when an element is described as being "directly on" or "directly interacting with" another element or layer, or as being "directly connected" or "directly coupled" to the same, there may be intervening elements or layers.Other words used to describe the relationship between elements should be interpreted similarly (such as "between" versus "directly between", "neighboring" or "adjacent" versus "directly adjacent" or "directly bordering", and the like). As used herein, the term "and / or" includes all combinations of one or more of the related items listed.

[0029] With reference to Fig. 1 comprises a vehicle bearing outer surface construction system 10 for use in a bearing system of a vehicle 11, and a bearing 12 having a bearing outer ring 14 and a bearing outside diameter (OD, outside diameter) 16. As mentioned herein, the vehicle 11 may include, but is not limited to, cars, trucks, vans, sport utility vehicles, autonomous vehicles, battery-powered electric vehicles, agricultural or construction equipment, rail vehicles, and the like. The bearing outer ring 14 comprises a first circumferential groove 18 and a second circumferential groove 20, also cut into the bearing outer ring 14. According to several aspects, a first depth 22 of the first circumferential groove 18 is essentially equal to a second depth 24 of the second circumferential groove 20.A first expansion element 26 is pre-positioned in the first circumferential groove 18, and a second expansion element 28 is pre-positioned in the second circumferential groove 20. In a first pre-positioned state, a first outer end face 30 of the first expansion element 26 is substantially flush or planar with an outer raceway surface 32 of the bearing outer ring 14, and a second outer end face 34 of the second expansion element 28 is also substantially flush or planar with the outer raceway surface 32 of the bearing outer ring 14.

[0030] According to other aspects, the first depth 22 of the first circumferential groove 18 can differ from the second depth 24 of the second circumferential groove 20. This difference can allow for different sizes of expansion elements and different bearing geometries.

[0031] Alternatively, according to several aspects, in a second pre-positioned state, the first outer end face 30 of the first expansion element 26 and the second outer end face 34 of the second expansion element 28 are recessed beneath the outer raceway surface 32 of the outer bearing ring 14. In this second pre-positioned state, the first expansion element 26 is therefore smaller than the outer diameter 16 of the outer bearing ring 14. Similarly, in this second pre-positioned state, the second outer end face 34 of the second expansion element 28 is also recessed beneath the outer raceway surface 32 of the outer bearing ring 14 and is therefore smaller than the outer diameter 16 of the outer bearing ring 14.

[0032] According to several aspects, the material of the first expansion element 26 and the material of the second expansion element 26 is an elastomeric rubber compound with acceptable hardness after swelling. According to several aspects, the elastomeric rubber compound can consist of VAMAC® G with a minimum hardness of 75 Shore A. According to several aspects, the material of the first expansion element 26 and the second expansion element 28 is a foam that expands upon entering one of the circumferential grooves, for example, by expansion from a compressed state, or that expands upon the subsequent application of a fluid.

[0033] With further reference to Fig. 1. According to several aspects, after the installation of the first expansion element 26 and the second expansion element 28 into the grooves of the bearing outer ring 14, a fluid 36 is applied to the first expansion element 26 and the second expansion element 28. The fluid 36 can be applied by spraying, by immersing the expansion elements in the fluid 36, or by spraying. The fluid can be petroleum-based, such as automatic transmission fluid (ATF), Petro-Lube Inc., NP-371, or Texaco Electrical Testing Laboratories (ETL) 7292 Europe. The fluid 36 can also be solvent-based, provided that the fluid 36 is compatible with the application environment.

[0034] One purpose of the fluid 36 is to cause material expansion of the first expansion element 26 and the second expansion element 28 so that they are positioned above the outer raceway surface 32 of the bearing outer ring 14.

[0035] Alternatively, the fluid 36 can be introduced into the first circumferential groove 18 and the second circumferential groove 20 before the installation of the first expansion element 26 and the second expansion element 28. In this way, the first expansion element 26 and the second expansion element 28 can begin absorbing the fluid 36 and thus begin expanding immediately after the installation of the first expansion element 26 and the second expansion element 28.

[0036] With reference to Fig. 2 and back again Fig. In Figure 1, the bearing 12 is slidably mounted in a housing 38 with the first expansion element 26 and the second expansion element 28. A gap 40, located between the outer raceway 32 of the bearing outer ring 14 and an inner surface 42 of the housing 38, allows a sliding fit between the outer raceway 32 and the bearing outer ring 14 during bearing installation. The first expansion element 26 and the second expansion element 28 are flexible to facilitate a sliding assembly process of the bearing 12 into the housing 38. The gap 40 is filled by the elastic expansion of the first expansion element 26 and the second expansion element 28. As already mentioned, the fluid 36 can be applied within the first circumferential groove 18 and the second circumferential groove 20 into the housing 38 before the mounting of the bearing 12, or onto the first expansion element 26 and the second expansion element 28 before or after the mounting of the bearing 12.The radial expansion of the first expansion element 26 and the second expansion element 28 occurs through absorption of the liquid 36 to close the gap 40.

[0037] With reference to Fig. 3 and again on Fig. 1 and Fig. 2. According to further aspects, the first circumferential groove 18 and the second circumferential groove 20 can be replaced by a single groove 46 of a modified bearing 12', which has a single groove width 48 that is equal to or greater than the width of the first circumferential groove 18 and / or the second circumferential groove 20. The single groove 46 can provide a wider and thus larger contact area between an expansion element 50 inserted into the single groove 46 and the inner surface 42 of the housing 38.

[0038] The designs of the bearing 12 and the modified bearing 12' of the present disclosure utilize the insulating material properties of one or more expansion elements to electrically insulate the bearing 12 or the modified bearing 12' from the housing 38 and to reduce the passage of electric current to the bearing 12 or the modified bearing 12', thereby reducing the risk of premature failure of the drive unit.In addition to the advantages of electrical insulation, after the expansion of the first expansion element 26 and the second expansion element 28, a frictional force 44 is generated between the outer raceway 32 of the bearing outer ring 14 and the inner surface 42 of the housing 38 by the absorption of the fluid 36. This frictional force is achieved by partially compressing the first expansion element 26 and the second expansion element 28, which reduces slippage between the outer raceway 32 of the bearing outer ring 14 and the inner surface 42 of the housing 38. This reduction in slippage helps to prevent bearing creep, which can otherwise occur if there is relative slippage between the outer raceway 32 of the bearing outer ring 14 and the inner surface 42 of the housing 38.The occurrence of creep can lead to premature failure of the drive unit and transmission if the bearing 12 or the modified bearing 12' is used in a drive unit or transmission of a vehicle 11.

[0039] According to several factors, the material of the expansion elements, including the first expansion element 26 and the second expansion element 28, has a minimum temperature resistance of approximately 150 °C. According to several factors, the gap 40 between the outer raceway surface 32 and the inner housing surface 42 has a nominal range of approximately 10 micrometers to approximately 20 micrometers when the bearing 12 and the housing 38 are at room temperature, and increases to approximately 30 micrometers to approximately 50 micrometers when the bearing 12 and the housing 38 are at system operating temperature. The materials of the expansion elements are therefore selected such that they have direct contact with the inner housing surface 42 above an installation temperature of at least approximately 10 micrometers to approximately 50 micrometers.

[0040] The vehicle bearing outer surface construction system 10 of the present disclosure provides a bearing outer ring with one or more grooves, the individual grooves containing an expansion rubber or foam material. The outer diameter 16 of the bearing 12 and the modified bearing 12' corresponds to, or is smaller than, the outer diameter 16 of the bearing 12 before swelling by oil absorption or expansion of a foam of the expansion element. The vehicle bearing outer surface construction system 10 of the present disclosure provides a combined use of an elastomer material(s) with absorption of a fluid(s) or by self-expansion of the expansion elements, for example, using an expansion foam material.The first expansion element 26 and the second expansion element 28 generate a frictional force 44 between the outer raceway surface 32 and the inner housing surface 42, which reduces bearing slippage.

[0041] A vehicle bearing outer surface design system 10 of the present disclosure offers several advantages. These include the use of expansion elements to eliminate creep caused by the relative slip between a bearing outer surface and a housing inner surface, without compromising the efficiency of the manufacturing process of a bearing assembly. The use of a combination of elastomer material(s) with a suitable fluid(s) to initiate the expansion of the expansion element generates a frictional force between a bearing outer ring and a housing bore surface to prevent slippage. The vehicle bearing outer surface design system 10 of the present disclosure provides a manufacturable design with minimal complexity. The vehicle bearing outer surface design system 10 of the present disclosure also provides effective and more cost-efficient electrical bearing insulation.

[0042] The vehicle bearing outer surface design system 10 of the present disclosure helps to prevent creep, which occurs when there is relative slip between a bearing outer surface and a housing inner surface. Creep can otherwise lead to gear wear, premature failure of the drive unit, and the transmission. The vehicle bearing outer surface design system 10 of the present disclosure isolates the bearing and ensures a high bearing impedance, so that instead of current attempting to flow through the bearing to ground, the current will flow through a suitable path, such as via grounded elements outside the housing.

Claims

[1] Vehicle storage exterior surface construction system comprising: a bearing having a bearing outer ring, the bearing outer ring including an outer ring surface; at least one circumferential groove formed in the bearing outer ring; an expansion element received in the at least one circumferential groove; and a housing accommodating the bearing having a gap between a housing inner surface and the bearing outer ring, wherein the expansion member expands to extend radially across the gap into direct contact with the housing inner surface to mitigate movement between the bearing and the housing inner surface. [2] The vehicle bearing outer surface construction system of claim 1, wherein the expansion member defines an elastomeric rubber. [3] The vehicle bearing outer surface construction system of claim 2, further comprising a fluid applied either into the at least one circumferential groove prior to installation of the expansion member or onto the expansion member during or after receiving the expansion member, which fluid initiates radial expansion of the expansion member to extend the expansion member out of the at least one circumferential groove. [4] The vehicle bearing exterior surface construction system of claim 3, wherein the fluid defines one of a petroleum-based fluid or a solvent-based fluid, the fluid being compatible with the application environment. [5] The vehicle bearing outer surface construction system of claim 1, further comprising a frictional force generated by direct contact between the expansion member and the housing inner surface. [6] The vehicle bearing exterior surface construction system of claim 1, wherein the expansion member defines an expansion foam, the expansion foam is received in the at least one circumferential groove, and expands to extend across the gap upon installation of the expansion foam. [7] The vehicle bearing outer surface construction system of claim 1, wherein the expansion member is positioned entirely within the at least one circumferential groove and is flush with, or recessed relative to, the outer race surface prior to expansion of the expansion member. [8] The vehicle bearing exterior surface construction system of claim 1, wherein: the at least one circumferential groove defines a first circumferential groove and a second circumferential groove; and the expansion element defines a first expansion element received in the first circumferential groove and a second expansion element received in the second circumferential groove. [9] The vehicle bearing outer surface construction system of claim 1, wherein a material of the expansion member includes an impedance that attenuates an electrical current passing between the bearing and the housing. [10] The vehicle bearing outer surface construction system of claim 1, wherein the at least one circumferential groove defines a first circumferential groove and a second circumferential groove, the first circumferential groove and the second circumferential groove individually defining a common circumferential groove width.

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