Rolling bearing device
By arranging multiple conductive elements between the inner ring and the outer ring of the rolling bearing device, the damage caused by the passage of rolling bearing current in the motor is solved, effective protection of rolling bearings is achieved, and maintenance costs and motor failure risks are reduced.
Patent Information
- Application Number
- CN202380073979.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-12-12
- Filing Date
- 2023-11-17
- Publication Date
- 2025-05-30
AI Technical Summary
When using rolling bearings in hybrid drivetrains of motor vehicles, current may pass through, resulting in voltage accumulation between bearing rings, breakdown and reduction, thereby damaging the raceway and rolling body, increasing maintenance workload and leading to premature motor failure.
A rolling bearing device is designed, including an inner ring, an outer ring and a rolling body, and a multi-part conductive element is arranged between the inner ring and the outer ring, the first part is connected to the inner ring or the outer ring in a conductive manner, and the second part is connected to the other bearing ring in a conductive manner and is rotatably movable to prevent undesired bearing current.
Effectively protecting the rolling bearing from undesired bearing currents without structural modifications to existing rolling bearings, conductive elements can be cost-effectively produced by standard manufacturing processes, and contact elements can be replaced individually to reduce wear.
Smart Images
Figure CN120077207A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a rolling bearing device, which includes a rolling bearing having an inner ring, an outer ring, and rolling elements, wherein the inner ring has an inner raceway and the outer ring has an outer raceway, and the rolling elements are mounted between the inner ring and the outer ring in a rolling manner, and a conductive element is arranged between the inner ring and the outer ring, and the conductive element electrically connects the inner ring to the outer ring in a conductive manner. Background Art
[0002] When using a rolling bearing, for example, in or on an electric motor or in a hybrid powertrain of a motor vehicle, current may pass through. For example, switching pulses from an inverter cause a voltage buildup between the bearing rings of the rolling bearing. This voltage is repeatedly reduced due to breakdown. Under adverse conditions, damage to the raceways and rolling elements is caused by the passage of current. This poses a risk of premature and unexpected failure of the bearing and thus the entire electric motor. In addition to the increased maintenance effort, additional costs are incurred due to machine downtime.
[0003] Electrically insulated rolling bearings are known in the prior art and are intended to prevent harmful bearing currents. For example, rolling bearings with ceramic insulation on the outer ring or the inner ring are used. However, electrically insulated rolling bearings are relatively expensive and are therefore not used frequently. Summary of the Invention
[0004] Therefore, in accordance with the known prior art, an object of the present invention is to provide a rolling bearing device with improved protection against harmful bearing currents. Another specific object of the present invention is to provide a rolling bearing device that provides protection against harmful bearing currents, particularly in a wet-running rolling bearing device.
[0005] This object is achieved by a rolling bearing device, which includes a rolling bearing having bearing rings and rolling elements, wherein one of the bearing rings is designed as an inner ring, and the other bearing ring is designed as an outer ring, and the inner ring has an inner raceway and the outer ring has an outer raceway, and the rolling elements are mounted between the inner ring and the outer ring in a rolling manner, and a multi-part conductive element is arranged between the inner ring and the outer ring, and the conductive element includes a first part and a second part, the first part is designed as a disk-shaped body and is connected to the inner ring or the outer ring in a conductive and rotationally fixed manner, the second part is electrically connected to the other bearing ring of the bearing rings, and the second part of the conductive element is arranged to move rotatably relative to the bearing rings and the first part of the conductive element.
[0006] The rolling bearing device according to the invention can effectively protect against unwanted bearing currents. In addition, the conductive element can be used without structural modification of an existing rolling bearing. The conductive element can also be produced very cost-effectively using standard manufacturing processes.
[0007] In addition, the contact element can preferably be detached from the conductive element individually, such that the contact element is designed to be replaced individually as a wear part.
[0008] First, the individual elements of the claimed subject matter of the invention are explained in the order in which these elements are mentioned in the claims, and thereafter a particularly preferred embodiment of the subject matter of the invention is described.
[0009] Rolling bearings can be used in particular to achieve a rotational movement with as low a frictional loss as possible. Rolling bearings can be used in particular to attach and / or mount axles and shafts, and depending on the design, rolling bearings can absorb radial forces and / or axial forces and at the same time enable the shaft or a component mounted on the axle in this way to rotate.
[0010] For this purpose, rolling elements are arranged to roll between the inner ring and the outer ring of the rolling bearing. Between these three main components - the inner ring, the outer ring and the rolling elements - rolling friction usually mainly occurs within the rolling bearing. Since the rolling elements in the inner and outer rings can preferably roll on hardened steel surfaces with optimized lubricants, the rolling friction of such bearings is relatively low.
[0011] The inner ring can in particular connect the shaft accommodating the rolling bearing to the rolling bearing or the rolling elements. In particular, the shaft can be connected to the side surface of the inner ring facing the shaft, and the rolling elements of the rolling bearing roll on the inner ring raceway opposite to this side surface. The inner ring can be made of metal and / or ceramic materials. In principle, it is conceivable to design the inner ring as one part or multiple parts, in particular two parts.
[0012] The outer ring can in particular connect the bearing system accommodating the rolling bearing to the rolling bearing or the rolling elements. In particular, the bearing system can be connected to the side surface of the outer ring facing the bearing system, and the rolling elements of the rolling bearing roll on the outer ring raceway opposite to this side surface. The outer ring can be made of metal material and / or ceramic materials. In principle, it is conceivable to design the outer ring as one part or multiple parts, in particular two parts.
[0013] Depending on the type of rolling bearing, the rolling element has the shape of a ball or a roller. The rolling element rolls on the raceways of the rolling bearing and has the task of transmitting the forces acting on a radial rolling bearing from the outer ring to the inner ring and vice versa. In an axial rolling bearing, the rolling element transmits the forces acting on the axial rolling bearing between the running disks. The roller-shaped rolling element is also referred to as a roller rolling element, and the spherical rolling element is called a bearing ball.
[0014] The roller-shaped rolling element can be selected, for example, from the group of symmetrical spherical rollers, asymmetrical spherical rollers, cylindrical rollers, needle rollers, and / or tapered rollers.
[0015] The rolling elements can be guided and spaced in a cage or by rolling element spacers. In principle, it is also conceivable to design a rolling bearing without a cage, which is also referred to as a full complement rolling bearing. In a full complement rolling bearing, adjacent rolling elements can be in contact with each other.
[0016] The rolling elements can roll within the rolling bearing, in particular on the inner raceway of the inner ring. For this purpose, the surface of the inner raceway can advantageously be designed to be wear-resistant, for example, by means of a corresponding surface treatment method and / or by applying a corresponding additional material layer. The inner raceway can be designed to be flat or profiled. For example, the profiled design of the inner raceway can be used to guide the rolling elements on the inner raceway. On the other hand, the flat form of the inner raceway can, for example, allow the rolling elements on the inner raceway to have a certain axial displaceability.
[0017] The rolling elements can roll within the rolling bearing, in particular on the outer raceway of the outer ring. For this purpose, the surface of the outer raceway can advantageously be designed to be relatively wear-resistant, for example, by means of a corresponding surface treatment method and / or by applying a corresponding additional material layer.
[0018] The outer raceway can be designed to be flat or profiled. For example, the profiled design of the outer raceway can be used to guide the rolling elements on the outer raceway. On the other hand, the flat form of the outer raceway can, for example, allow the rolling elements on the outer raceway to have a certain axial displaceability.
[0019] Generally, undefined contacts between mechanical elements in rotating components are avoided. Therefore, the guiding elements known from the prior art are clamped in a fixed position or subjected to a defined sliding movement. In contrast, within the scope of the present invention, the opposite is proposed, thereby achieving an ideal friction-minimized current dissipation.
[0020] Preferably, the second part of the conductive element of the rolling bearing device is not rotationally fixed, but is arranged in a manner that it can move rotationally, i.e., it is floatingly arranged in the same axial plane as the first part of the conductive element. Thus, the second part of the conductive element is only radially offset relative to the first part. This is particularly advantageous because the required installation space is minimized, and at least in the sense of a labyrinth seal, the first part of the conductive element can still utilize the sealing effect. Regarding the installation of the rolling bearing device, this preferred design does not affect the installation space.
[0021] In particular, it is preferred that the second part of the conductive element is designed as an annular ring. Thus, similar to a wire loop, it makes partial tangential contact in the space between the first part of the conductive element and the bearing ring, and the bearing ring is not arranged to be in direct electrical contact with the first part of the conductive element. It should be emphasized that the second part of the conductive element only has the shape of a wire loop, but does not necessarily consist of a metal wire.
[0022] To ideally guide the second part of the conductive element of the rolling bearing device, it is proposed to provide a geometric profile extending circumferentially in one of the bearing rings with direct electrical contact. This represents a particular advantage because bearing rings with known profiles, i.e., with recesses for previously used sealing solutions, can be used.
[0023] It is also conceivable that the guidance of the second part of the conductive element is achieved by a concave profile extending circumferentially on the circumference of the first part of the conductive element. Thus, the bearing ring that does not contact the first part of the conductive element only needs to have a cylindrical surface.
[0024] To ensure long-term constant electrical conductivity, the second part of the conductive element contacts the bearing ring and the first part of the conductive element with which it is in direct electrical contact under a slight prestress.
[0025] In a preferred embodiment, the first part of the conductive element of the rolling bearing device is designed as a cover disk made of steel. This represents a simple and cost-effective way to implement the present invention, which is suitable in terms of forming. It is conceivable that this may also have a coating that improves electrical conductivity or affects friction. The movement behavior of the second part of the conductive element may be affected by the friction-influencing coating.
[0026] In another preferred embodiment of the rolling bearing device, the second part of the conductive element comprises carbon or carbon fibers. This has the advantage of particularly high electrical conductivity and ensures good forming.
[0027] However, it is also conceivable that the second part of the conductive element of the rolling bearing device is formed by a flat wire or a round wire made of spring steel. This may be advantageous under specific operating conditions. Description of the Drawings
[0028] The present invention will now be explained in more detail with reference to the accompanying drawings without limiting the general concept of the invention.
[0029] In the drawings:
[0030] Figure 1a and Figure 1b a first embodiment of a rolling bearing with a conductive element is shown in a schematic cross - section;
[0031] Figure 2a and Figure 2b a second embodiment of a rolling bearing with a conductive element is shown in a schematic cross - section;
[0032] Figure 3a and Figure 3b a cross - section of a conductive bearing is shown, which shows two guiding options for the conductive element. Detailed Description
[0033] Figure 1a and Figure 1b shows a first embodiment of a rolling bearing device 1, which includes a rolling bearing 2 having an inner ring 3, an outer ring 4, and a rolling body 5. The inner ring 3 has an inner - ring raceway 6 and the outer ring 4 has an outer - ring raceway 7. The rolling body 5 is mounted in a rolling manner between the inner ring 3 and the outer ring 4, and a conductive element 8 is arranged between the inner ring 3 and the outer ring 4, and the conductive element conductively connects the inner ring 3 to the outer ring 4.
[0034] The conductive element 8 is multi - part, and a first part 9 is designed as a disc - shaped body and is conductively and rotationally fixed to the outer ring 4 in Figure 1a and Figure 1b In addition, the conductive element includes a second part 10, which is conductively connected to the inner ring 3 and is arranged to be rotatable relative to the inner ring 3 and the first part 9 of the conductive element.
[0035] The second part 10 of the conductive element 8 and the first part 9 of the conductive element 8 are arranged in the same axial plane.
[0036] Figure 1a A rolling bearing device 1 at 0° is shown in a schematic cross - section. Figure 1b A rolling bearing device is shown in a schematic cross - section when the rolling bearing device can be configured, for example, at 90° in the rotational direction. It is clear here that the second part 10 of the conductive element can thus be designed asymmetrically and can thus be elastically prestressed relative to the inner ring 3 and the first part 9 of the conductive element. It can be clearly seen from FIG. 1 that the second part 10 of the conductive element can be designed in the form of a ring, for example in the form of a wire.
[0037] It can be further clearly seen from Figure 1a and Figure 1b that the second part 10 of the conductive element 8 is guided by a geometric profile extending circumferentially in one of the inner rings 3 in direct electrical contact.
[0038] The second part 10 of the conductive element 8 can also be guided by a profile, for example, a profile with a concave cross-section and extending circumferentially. These two options can be implemented individually or in combination.
[0039] Figure 2a and Figure 2b show another embodiment, in which the first part of the conductive element 8 is conductively and rotationally fixed to the inner ring 3. The second part 10 of the conductive element is conductively connected to the outer ring 4 and is arranged to be rotatable relative to the outer ring 4 and the first part 9 of the conductive element.
[0040] As Figure 1a and Figure 1b shown, Figure 2a the rolling bearing device 1 at 0° is also shown in a schematic cross-section, and Figure 1b a conceivable state at 90° in the rotational direction is shown in a schematic cross-section.
[0041] Figure 3a and Figure 3b show two guiding options for the conductive element. In Figure 3a , the second part 10 of the conductive element is guided by the bearing ring 3 or 4. As with Figure 1a and Figure 1b and Figure 2a and Figure 2b the same, Figure 3a and Figure 3b show the conceivable positions of the second part of the conductive element at 0° and 90° in the rotational direction in a schematic cross-section.
[0042] Special profiles can be provided, or in the case of an existing bearing ring design, the recesses or seats of the seals can be directly used. In Figure 3b , the second part 10 of the conductive element is guided by the first part 9 of the conductive element. The profile for this purpose can be seen here.
[0043] For both guiding options, the opposing surfaces are shown as cylindrical surfaces. However, it is also conceivable to combine the above two guiding options. Even during bearing operation, this will not lead to over-determination, because on the one hand, the second part 10 of the conductive element has a certain elasticity and does not have a fixed seat, and can therefore move rotatably relative to the two contact mating parts.
[0044] The present invention is not limited to the embodiments shown in the drawings. Therefore, the above description should not be considered restrictive, but rather illustrative. The appended claims should be understood to mean that the stated features exist in at least one embodiment of the present invention. This does not exclude the existence of other features. Where the claims and the above description define a "first" feature and a "second" feature, such designations are used to distinguish between two features of the same type and do not limit the order of precedence.
[0045] List of Reference Numerals
[0046] 1 Rolling bearing device
[0047] 2 Rolling bearing
[0048] 3 Inner ring
[0049] 4 Outer ring
[0050] 5 Rolling element
[0051] 6 Inner ring raceway
[0052] 7 Outer ring raceway
[0053] 8 Conductive element
[0054] 9 First part of the conductive element
[0055] 10 Second part of the conductive element
Claims
1. A rolling bearing device (1), the rolling bearing device comprising a rolling bearing (2) having bearing rings (3, 4) and rolling elements (5), wherein, one of the bearing rings (3, 4) is designed as an inner ring (3) and the other bearing ring is designed as an outer ring (4), and wherein the inner ring (3) has an inner raceway (6) and the outer ring (4) has an outer raceway (7), and the rolling elements (5) are mounted in a rolling manner between the inner ring (3) and the outer ring (4), and a multi-part conductive element (8) is arranged between the inner ring (3) and the outer ring (4), and the conductive element comprises a first part (9) which is designed as a disc-shaped body and is connected to the inner ring (3) or the outer ring (4) in a conductive and rotationally fixed manner, and the conductive element comprises a second part (10) which is conductively connected to the other bearing ring of the bearing rings (3, 4), characterized in that the second part (10) of the conductive element (8) is arranged to be rotatable relative to the bearing rings (3, 4) and the first part (9) of the conductive element (8).
2. The rolling bearing device (1) according to claim 1, characterized in that, the second part (10) of the conductive element (8) and the first part (9) of the conductive element (8) are arranged in the same axial plane.
3. The rolling bearing device (1) according to claim 1 or 2, characterized in that, the second part (10) of the conductive element (8) is designed to be annular.
4. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, the second part (10) of the conductive element (8) is guided by a geometric profile extending circumferentially in one of the bearing rings in direct electrical contact with the bearing rings (3, 4).
5. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, the second part (10) of the conductive element (8) is guided by a concave profile extending circumferentially in the first part (9) of the conductive element (8).
6. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, the second part (10) of the conductive element (8) contacts the first part (9) of the conductive element and the part of the bearing rings (3, 4) in direct electrical contact with the second part under a slight prestress.
7. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, the first part (9) of the conductive element (8) is designed as a covering disc made of steel.
8. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, the second part (10) of the conductive element (8) comprises carbon or carbon fiber.
9. The rolling bearing device (1) according to any one of the preceding claims, characterized in that, The second part (9) of the conductive element (8) is formed by a flat wire or a round wire made of spring steel.