Description:TECHNICAL FIELD
[0001] The present invention generally relates to field of a bearing. More particularly, the invention relates to a conductive wire in the bearing.
BACKGROUND
[0002] Generally, a conductive bearing includes a conductive wire. The conductive wire may serve as continuous supply of current between an inner ring and an outer ring of the bearing. Further, the conductive wire includes a contact portion in contact with the inner ring of the bearing. Over time, the contact portion of the conductive wire may get damaged or may wear out due to rotation of the inner ring of the bearing. Wearing out of the conductive wire, may result in disconnection of the supply of current between the inner ring and the outer ring of the bearings. Further, wearing out of the contact portion may result in opposing electric current between the inner ring and the out ring of the bearing (i.e. electric pitting may arise).
[0003] The conductive bearing may be used in a variety of application including but not limited to an automotive application. For example, the conductive bearings may be required for an upper column steering. In an example the bearing application may be grounded to blow a horn. Passing a current through the conductive wire in the bearing results in smooth functioning of the horn. The contact portion of the conductive wire may damage or wear out over the time resulting in disconnecting the supply of current in the bearing. Hence, the horn will not blow due to insufficient grounding.
[0004] Conventional contact portion of the conductive wire design may include very less contact portion for the bearing. For example, US patent number US 3271723 A describes a conductive ball bearing including a snap-ring type electrically conductive shunt member. The electrically conductive shunt member seems to have an inwardly extending portion which makes a sliding electrical contact with a portion of the outer surface of the inner ring of the bearing. Additionally, the US 3271723 A patent seems to describe the sliding electrical contact with a portion of the bearing. In addition the patent teaches reduction of the wear on the contact portion by having a coating layer of silver or gold.
[0005] Accordingly, there remains the need for less wearing out of the contact portion of the conductive wire for the bearing and in particular the contact portion associated with force, which obviates the aforesaid drawbacks.

SUMMARY OF THE INVENTION
[0006] An object of the present invention is to provides a conductive wire (2) in a bearing (20). The conductive wire (2) in the bearing (20) includes a first segment (4) and a second segment (6). The second segment (6) further includes at least one contact portion (16) and at least one bend portion (14). The bearing (20) includes an inner ring (22) and an outer ring (24). The at least one contact portion (16) is associated with an outer circumference (28) of the inner ring (22) of the bearing (20). The at least one bend portion (14) comprises a bend angle (O) such that a force exerted by the at least one contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) is in a range of about 2 Newton to about 2.5 Newton.

BRIEF DESCRIPTION OF DRAWINGS
[0007] The embodiments of the invention are illustrated in the accompanying drawings, throughout which the reference letters indicate corresponding part in the various figures. The embodiments herein will be better understood from the following description with reference to the drawings, in which:
[0008] FIG. 1 illustrates an end elevation view of a conductive wire in accordance with an embodiment of the invention.
[0009] FIG. 2 illustrates an end elevation view of a portion of the conductive wire in accordance with an embodiment of the invention.
[0010] FIG. 3 illustrates an end elevation view of a bearing in accordance with an embodiment of the invention.
[0011] FIG. 4 shows a graph of a contact portion and a curvature in accordance with an embodiment of the invention.
[0012] FIG. 5 shows a graph of a surface to surface relative motion and speed in accordance with an embodiment of the invention.
[0013] FIG. 6 shows a graph of a wear at the contact portion and a surface to surface relative motion in accordance with an embodiment of the invention.
[0014] FIG. 7 shows a graph of a wear rate and a bend angle (O) in accordance with an embodiment of the invention.
[0015] FIG. 8 shows a graph of a supply current passed through the conductive wire and the bend angle (O) in accordance with an embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION
[0016] The singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not. “Substantially” means a range of values that is known in the art to refer to a range of values that are close to, but not necessarily equal to a certain value.
[0017] Other than in the examples or where otherwise indicated, all numbers or expressions referring to quantities of ingredients, reaction conditions, and the like, used in the specification and claims are to be understood as modified in all instances by the term “about.” In some aspects of the current disclosure, the terms “about” or “approximately” are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the terms are defined to be within 10%, alternatively within 5%, alternatively within 1%, or alternatively within 0.5%.
[0018] Directional terms used herein are made with reference to the views and orientations shown in the exemplary figures. A central axis may be shown in the figures and described below. Terms such as “outer” and “inner” are relative to the central axis. For example, an “outer” surface means that the surface faces away from the central axis, or may be outboard of another “inner” surface. Terms such as “diameter,” “circumference,” etc. also are relative to the central axis.
[0019] An object of the present invention provides a conductive wire (2) in a bearing (20). The conductive wire (2) in the bearing (20) includes a first segment (4) and a second segment (6). The second segment (6) further includes at least one contact portion (16) and at least one bend portion (14). The bearing (20) includes an inner ring (22) and an outer ring (24).The at least one contact portion (16) is associated with an outer circumference (28) of the inner ring (22) of the bearing (20). The at least one bend portion (14) comprises a bend angle (O) such that a force exerted by the at least one contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) is in a range of about 2 Newton to about 2.5 Newton.
[0020] The conductive wire for the bearing in accordance with one embodiment of the present invention will now be described with reference to the drawings.
[0021] As shown in FIG. 1, an end elevation view of the conductive wire (2) includes the first segment (4) and the second segment (6). The first segment (4) of the conductive wire (2) has a circular diameter (8) and extends about a central axis (12). The conductive wire (2) subtends an open angle (10).
[0022] The first segment (4) of the conductive wire (2) has the circular diameter (8) as shown in FIG. 1 according to an example embodiment of the present invention. In one embodiment of the present invention, the circular diameter (8) of the conductive wire (2) in a range from about 105 % to about 125 % of an inner circumference (32) of the outer ring (24) of the bearing (20). In another embodiment of the present invention, the circular diameter (8) of the conductive wire (2) in the range from about 113 % to about 115 % of the inner circumference (32) of the outer ring (24) of the bearing (20). In another embodiment of the present invention, the conductive wire (2) subtends with the open angle (10) may be suitable for placement of a contact portion in terms of balance and grip. In one embodiment of the present invention, the open angle of the conductive wire (2) in a range from about 110 degrees to about 120 degrees. In another embodiment of the present invention, the first segment (4) of the conductive wire (2) has a length in a range from about 55% to about 75% of circumference of the inner circumference (32) of the outer ring (24) of the bearing (20). In yet another embodiment of the present invention, the conductive wire (2) thickness may be about 0.1 to 1.5 millimetre.
[0023] FIG. 2 shows an end elevation view of the second segment (6) of the conductive wire (2) in accordance to an embodiment of the invention. In an example embodiment of the invention, the second segment (6) includes the contact portion (16) and the bend portion (14). In one embodiment of the present invention, the contact portion (16) and the bend portion (14) may be positioned at one of the end of the first segment (4) of the conductive wire (2). In another embodiment of the present invention, the contact portion (16) and the bend portion (14) may be positioned at both ends of the first segment (4) of the conductive wire (2) as shown in FIG.1. In yet another embodiment of the present invention, the bend portion (14) of the conductive wire (2) includes the bend angle (O). Further, the bend portion (14) includes an angular end (18) at the end of the contact portion (16). Furthermore, the conductive wire (2) material made up of a conductive material. The conductive material may include but not limited to a SS304 without coating.
[0024] As depicted in an example embodiment of FIG.2, the second segment (6) of the conductive wire (2) includes the contact portion (16) and the bend portion (14). In one embodiment of the present invention, the contact portion (16) may be associated with the outer circumference (28) of the inner ring (22) of the bearing (20). In another embodiment of the present invention, the contact portion (16) of the conductive wire (2) has a diameter in a range from about 100 % to about 115 % of the outer circumference (28) of the inner ring (22) of the bearing (20). In yet another embodiment of the present invention, the contact portion (16) has the diameter in the range from about 101 % to about 105 % of the outer circumference (28) of the inner ring (22) of the bearing (20). In another embodiment of the present invention, the contact portion (16) of the conductive wire (2) has a length of at least 1/12 of an inner circumference (32) of the outer ring (24) of the bearing (20).
[0025] As shown in FIG. 3, the bearing (20) includes the outer ring (24) and the inner ring (22) according to an embodiment of the invention. As depicted in FIG. 3, the outer ring (24) and the inner ring (22) extends around the central axis (12). The outer ring (24) has an outer circumference (30) and the inner circumference (32) facing away from the central axis (12). The inner ring (22) has an outer circumference (28) and an inner circumference (26) facing the central axis (12). In an example embodiment of the present invention, the bearing (20) has a plurality of rolling elements (not shown in the figure). The rolling elements rest between the inner surface of the outer ring (24) and the outer surface of the inner ring (22). In one embodiment of the present invention, the rolling elements are retained, and can fully rotate via a cage between the inner surface of the outer ring (24) and outer surface of the inner ring (22). In other embodiment of the present invention, the rolling elements enable relative rotational movement between the outer ring (24) and the inner ring (22) of the bearing (20). In an example embodiment, the bearing (20) may be one of a ball bearing, a deep groove ball bearing, a thrust ball bearing, a cylindrical roller bearing, a spherical roller bearing, a tapered roller bearing, a needle roller bearing.
[0026] A graph shown in FIG. 4, depicts the contact portion and a curvature in accordance with an embodiment of the invention. As shown in FIG.4, the contact portion (16) of the conductive wire (2) on the outer circumference (28) of the inner ring (22) of the bearing (20) provide a required frictional force for given optimum curvature of the conductive wire (2). As shown in FIG. 4, the graph describes that the contact portion (16) of the conductive wire (2) decreases with increase in the curvature of the conductive wire (2). Hence, it is seen from FIG.4 that an optimized curvature for the contact portion (16) may be considered for designing the conductive wire (2).
[0027] In FIG. 5, the given graph shows a surface to surface relative motion and speed of the rotational movement of the outer ring (24) and the inner ring (22) of the bearing (20) with conductive wire (2) according to an embodiment of the invention. In an example embodiment, the surface to surface relative motion of the conductive wire (2) includes an outer relative setup and an inner relative setup. In one embodiment of the present invention, the outer relative setup includes the inner circumference (32) of the outer ring (24) of the bearing (20) and the inner relative setup includes the outer circumference (28) of the inner ring (22) of the bearing (20). As shown in the FIG. 5, the graph describes surface to surface relative motion of the outer relative setup is more than the inner relative setup. Therefore, in an embodiment of the present invention, the surface to surface relative motion of the inner relative setup may be considered for designing the conductive wire (2) instead of the outer relative setup.
[0028] The graph shown in FIG. 6, shows the wear at the contact portion and surface to surface relative motion according to an embodiment of the present invention. In an example figure, the wear may be at the contact portion (16) of the conductive wire (2) of the inner relative setup which includes the outer circumference (28) of the inner ring (22) of the bearing (20). The graph in FIG. 6 describes, that the wear at the contact portion (16) of the conductive wire (2) increases with the surface to surface relative motion. Therefore, in a preferred embodiment of the present invention, the contact portion (16) of the conductive wire (2) of the inner relative setup may be considered for designing the conductive wire (2).
[0029] In one embodiment of present invention, the conductive wire (2) may be part of the bearing (20). In another embodiment of the present invention, the conductive wire (2) may be snapped by an assembly method to contact the conductive wire (2) to the outer circumference (28) of the inner ring (22) and the inner circumference (32) of the outer ring (24) of the bearing (20). In yet another embodiment of the present invention, the conductive wire (2) may be coupled to the outer circumference (28) of the inner ring (22) and the inner circumference (32) of the outer ring (24) of the bearing (20). In yet another embodiment of the present invention, the conductive wire (2) creates a pathway between the outer ring (24) and inner ring (22) for flow of electrical current.
[0030] In one embodiment of the present invention, the bend portion (14) includes a bend angle (O) such that a force exerted by the contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20). The force exerted by the contact portion (16) may be in a range of about 2 Newton to about 2.5 Newton. Hence, the bend angle (O) may be calculated by the force exerted by the contact portion (16).
[0031] In one embodiment of the present invention, the bend angle (O) increases when the force and wear rate of the contact portion (16) increases as shown in the graph of FIG 7. In an example embodiment, if the bend angle (O) decreases the supply current passed through the conductive wire (2) may be inappropriate.
[0032] Generally, based on a physical experiment and finite element analysis the bend angle (O) may be calculated by retaining the force constant. In one embodiment of the present invention an optimum angle (O1) at a point (34) as shown in the graph FIG. 8 such that supply current passed through the conductive wire (2) remains constant for further increase in the bend angle (O). Further, in another embodiment of the present invention, as the wear rate of the contact portion (16) of the conductive wire (2) decreases, a decrease may be noted with the calculated optimum angle (O1) at the point (34). According to an embodiment of the present invention, by retaining the force constant for the contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) results in a constant supply current passed through the conductive wire (2). In another embodiment of the present invention, the supply current passed through the conductive wire (2) may be in a range from about 2.5 Ampere to about 3.5 Ampere. In yet another embodiment of the present invention, the supply current passed through the conductive wire (2) may be less than about 3 Ampere.
[0033] Table 1 shows an experimental data for the bend angle (O) and current passed through the conductive wire (2).
Sl.no Current in Ampere Bend Angle (O)
1 2 100
2 3 105
3 3 110
Table 1
[0034] It may be noted from the experimental data of Table 1 and the graph of FIG. 8 the current remains constant for an increases in the bend angle (O), after the optimum angle (O1) at a point (34) is reached. In an embodiment of the present invention the design of the conductive wire (2) of the invention such that the force exerted by the contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) results in the constant supply current passed through the conductive wire (2).
[0035] Conventionally a maximum force applied to the contact portion of the conductive wire may be 5.4 Newton. In an embodiment of the present invention, the force exerted by the contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) may be around 2 Newton. In another example embodiment of the present invention, the force results in a reduce torque of the bearing (20) and may reduce wear rate with improved conductivity of the conductive wire (2). In another embodiment of the present invention, the reduced wear rate and improved conductivity of the conductive wire (2), it can function for at least about 1 million cycle operations.
[0036] According to another embodiment of the present invention, the angular end (18) positioned at the end of the contact portion (16) as shown in FIG. 2. In an example embodiment of the invention, the angular end (18) may be positioned at both ends of the contact portion (16) of the conductive wire (2) as shown in FIG. 1. In one embodiment of the present invention, the angular end (18) may be at angle with respect to contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20). In another embodiment of the present invention, the angular end (18) at the end of the contact portion (16) may be at angle in a range from about 100 degrees to about 135 degrees. In yet another embodiment of the present invention, the angular end (18) at the end of the contact portion (16) prevents damage during rotation. In some embodiments of the present invention, the angular end portion of the conductive wire (2) has a length in a range from about 5 millimeters to about 10 millimeters.
[0037] The conductive bearing of the present invention may be used in many applications. The application include an automotive and non-automotive category. In an example embodiment, the automotive application includes but not limited to bearing categories. In an example embodiment of the present invention the bearing could include an electrical power steering in a passenger car, a commercial vehicle, an electric rickshaw, an electric-scooter, an electric motor.
[0038] Advantages: The technical advantages brought in by the present invention are as follows:
1. Reduced contact forces due to reduced torque rotation.
2. Reduced wear rate due to low force.
3. Improved current passing through conductive wire.
4. Improved contact area due to improved conductivity.
5. Improved surface finish due to reduced contact wear.
6. Easy to assemble.
7. Easy to manufacture.
8. Conductive wire design may be applicable to any different size of the bearings.
[0039] While considerable emphasis has been placed herein on the components and component parts of the various embodiments, it will be appreciated that many embodiments can be made and that many changes can be made in the embodiments without departing from the scope and spirit of the invention. These and other changes in the various embodiment 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.

Claims:

I/WE CLAIM:

1. A conductive wire (2) in a bearing (20) comprising:
a first segment (4); and
a second segment (6) comprising at least one contact portion (16) and at least one bend portion (14),
wherein the bearing (20) comprises an inner ring (22) and an outer ring (24), the at least one contact portion (16) is associated with an outer circumference (28) of the inner ring (22) of the bearing (20) and the at least one bend portion (14) comprises a bend angle (O) such that a force exerted by the at least one contact portion (16) on the outer circumference (28) of the inner ring (22) of the bearing (20) is in a range of about 2 Newton to about 2.5 Newton.
2. The conductive wire (2) as claimed in claim 1, wherein the at least one bend portion (14) further comprises an angular end (18).

3. The conductive wire (2) as claimed in claim 2, wherein the angular end (18) is at angle in a range from about 100 to about 135 degrees with respective to the outer circumference (28) of the inner ring (22) of the bearing (20).

4. The conductive wire (2) as claimed in claim 2, wherein the angular end portion (18) has a length in a range from about 5 millimeters to about 10 millimeters.

5. The conductive wire (2) as claimed in claim 1, wherein the at least one contact portion (16) has a diameter in a range from about 100 % to about 115 % of the outer circumference (28) of the inner ring (22) of the bearing (20).

6. The conductive wire (2) as claimed in claim 1, wherein the at least one contact portion (16) has a length of at least 1/12 of an inner circumference (32) of the outer ring (24) of the bearing (20).

7. The conductive wire (2) as claimed in claim 1, wherein the first segment (4) has a circular diameter (8) in a range from about 105 % to about 125 % of inner circumference (32) of the outer ring (24) of the bearing (20).

8. The conductive wire (2) as claimed in claim 1, wherein the first segment (4) has a length in range from about 55% to about 75% of circumference of the inner circumference (32) of the outer ring (24) of the bearing (20).

9. The conductive wire (2) as claimed in claim 1, wherein the bearing (20) is at least one selected from a ball bearing, a deep groove ball bearing, a thrust ball bearing, a cylindrical roller bearing, a spherical roller bearing, a tapered roller bearing, a needle roller bearing.

10. The conductive wire (2) as claimed in claim 1, wherein the conductive wire (2) in the bearing (20) is associated with an electrical power steering of a vehicle.

11. The conductive wire (2) as claimed in claim 1, wherein the conductive wire (2) is coupled to the outer circumference (28) of the inner ring (22) of the bearing (20) and the inner circumference (32) of the outer ring (24) of the bearing (20).

12. The conductive wire (2) as claimed in claim 11, wherein a continuous supply current passed through the conductive wire (2) is in a range from about 2.5 Ampere to about 3.5 Ampere.