Bearing arrangement

Abstract

The invention relates to a bearing arrangement comprising a rolling bearing, a shaft (4, 31) with a centrifugal disc (6) arranged thereon, and a housing (5) with a sealing ring (10) arranged thereon, wherein an extension (7) of the centrifugal disc (6) circumferentially frames a part (12) of the housing (5), and at least the part (12) of the housing (5) forms an undercut (13) in the axial direction (a) and in the radial direction (r) with the extension (7) of the centrifugal disc (6). The extension (7) has, on an inner side (15) of the centrifugal disc (6) facing the shaft (4, 31), a reduction of a first diameter (d1) to a second diameter (d2). The housing (5) has, on an outer side (16) facing the inner side (15) of the centrifugal disc (6), a reduction of a third diameter (d3) to a fourth diameter (d4).

Description

Field of the invention

[0001] The invention relates to a bearing arrangement comprising a rolling bearing which is arranged about an axis of rotation running in the axial direction, a shaft running in the axial direction, a housing, a centrifugal disc arranged on the shaft, which centrifugal disc has an extension running in the axial direction and a base body running in the radial direction with a first catch arm, which extension frames part of the housing all the way around and at least part of the housing forms an undercut in the axial direction and in the radial direction with the extension of the centrifugal disc and comprising a sealing ring arranged on the housing, which has a first sealing lip which extends in the direction of the base body of the centrifugal disc, wherein the first catch arm of the centrifugal disc extends towards the sealing ring. Background of the invention

[0002] DE 10 2022 130 974 A1 discloses a bearing arrangement with a pre-sealing element (flinger disc) and a bearing-side radial shaft seal in a gearbox (see Fig. 1, Fig. 2). The pre-sealing element overlaps a housing section with a ring-like extension.

[0003] DE 10 2016 209 109 A1 discloses a bearing with a two-part sealing device arranged between an outer ring and an inner ring. A first part is arranged on the inner ring, extends in a C-shape with several steps, and encloses part of the outer ring. A second part of the sealing device is arranged on the outer ring. It touches the first part of the sealing device with both a sealing lip extending in the radial direction and two sealing lips extending predominantly in the axial direction.

[0004] JP 7137184 B2 discloses a two-part sealing device. A first part of the sealing device consists of a stepped cover plate. A second part of the sealing device has two sealing lips that are tangent to the cover plate in the radial direction and one sealing lip that is tangent to the cover plate in the axial direction. The cover plate is arranged on a first component, and the second part with the sealing lips is arranged on a second component. The cover plate encloses a region of the second component with a section extending in the axial direction and has a projection that extends in the axial direction toward the second part of the sealing device. Object of the invention

[0005] The invention is based on the object of providing a bearing arrangement with an improved sealing effect. Description of the invention

[0006] According to the invention, this object is achieved in that the extension of the centrifugal disc has a reduction of a first diameter to a second diameter on an inner side of the centrifugal disc facing the shaft, wherein the housing has a reduction of a third diameter to a fourth diameter on an outer side of the housing facing the inner side of the centrifugal disc, wherein a sealing gap is formed between the inner side of the centrifugal disc and the outer side of the housing.

[0007] Alternatively, this object is achieved in that the part of the housing has first depressions on an outer side of the housing facing the extension of the centrifugal disc and in that an inner side of the extension facing the part of the housing has second depressions, which first and second depressions are present as circumferential grooves.

[0008] To ensure adequate functionality of rolling bearings, they must be protected from ambient interference such as dirt particles or fluids in their installation location. Particularly in high-speed applications, such as in electric motors, such interference, especially dirty water, can drastically impact functionality, even leading to vehicle failure.

[0009] To remedy this, the bearing assembly according to the invention is used. A cover plate, also known as a centrifugal disc due to its functionality, is located on the shaft of the bearing assembly.

[0010] During operation, the shaft rotates, and with it the flinger mounted on the shaft. The shaft is at least one shaft, meaning the flinger can also be mounted on another shaft which rotates and is connected to the first shaft. Liquids or other particles striking the flinger are thrown away by the rotational movement. The housing remains static during operation. A sealing ring, in particular a radial shaft sealing ring, is arranged on the housing. The flinger is designed in such a way that, in addition to a foot with which it sits on the shaft, it consists of a base body and an extension, with the base body merging into the extension. The base body runs radially between the housing and the shaft. The base body is preferably straight, i.e. without any further curves, in order to have a high rebound effect.The extension runs along the rotational axis, i.e., in the axial direction. The base body has a first catching arm, which extends toward the sealing ring. The first catching arm is a projection protruding from the base body. The sealing ring has a first sealing lip, which projects toward the base body of the flinger. Thus, the first catching arm and the first sealing lip form barriers to prevent disruptive dirt or water particles from entering the interior of the rolling bearing.

[0011] If disruptive particles or liquids have already penetrated these barriers, they are already very close to the rolling bearing. Especially at high operating speeds, particles at very high speeds and liquids impact the first catch arm and the first sealing lip with enormous pressure. The first sealing lip, in particular, is at risk of allowing particles or liquids to pass through. Penetrating particles and dirty water corrode and wear the rolling bearing, as well as the sealing ring and the flinger, causing the sealing effect to be lost and, in the medium term, potentially leading to the failure of the bearing assembly and the vehicle.

[0012] A key challenge in rolling bearings for electric motors is preventing dirty water from penetrating the bearing. Simply placing a seal directly in front of the bearing is not enough; rather, the problem of potential dirty water ingress must be addressed in the area surrounding the bearing. To this end, basic components required for the application are used to create an upstream sealing gap. The sealing gap is a gap whose function is to prevent, or at least impede, the ingress of ambient media, such as dirt particles or liquids, into the interior of the bearing. To this end, the flinger is positioned so that its extension surrounds part of the housing.The housing or the extension of the centrifugal disc are designed such that the part of the housing framed by the extension at least partially overlaps the extension in both the axial direction and the radial direction. In particular, the housing and the extension of the centrifugal disc are designed such that the part of the housing framed by the extension at least partially overlaps the extension in both the axial direction and the radial direction. Preferably, the part of the housing framed by the extension of the centrifugal disc and an immediately adjacent region of the housing are arranged in an at least partial overlap with the extension of the centrifugal disc in both the axial direction and the radial direction. In this way, an undercut is formed in two spatial directions between the extension of the centrifugal disc and the housing.

[0013] This two-way undercut creates a labyrinth-like pre-seal using existing components. The pre-seal itself reduces the ingress of dirty water. During operation, the rotation of the shaft, depending on the design, can also create a siphon effect in the pre-seal, which creates excess pressure, making it even more difficult for dirty water to enter. At the same time, the two-way undercut reduces the speed of incoming dirty water. Even if dirty water overcomes the pre-seal, the low pressure of the fluid, which in turn is achieved by slowing the dirty water down in the labyrinth, means that the sealing lip of the sealing ring is hardly stressed. This means that only a small amount of dirty water can penetrate into the interior space between the sealing ring and the centrifugal disc at low speed.The design of the bearing assembly, with its labyrinth-like arrangement of components, creates a complex flow path. This slows down dirty water and seals the rolling bearing.

[0014] Furthermore, the solution according to the invention according to the main claim includes that the extension of the centrifugal disc has a reduction from a first diameter to a second diameter on an inner side of the centrifugal disc facing the shaft, and that the housing has a reduction from a third diameter to a fourth diameter on an outer side of the housing facing the inner side of the centrifugal disc, wherein a sealing gap is formed between the inner side of the centrifugal disc and the outer side of the housing. Preferably, a first diameter is present and is measured from the inner side of the extension of the centrifugal disc to the radially opposite inner side of the extension of the centrifugal disc. A second diameter is measured from the inner side of the extension of the centrifugal disc to the radially opposite inner side of the extension of the centrifugal disc, but with an offset in the axial direction.The first diameter is larger than the second diameter. The extension of the centrifugal disc reduces its distance from the axis of rotation. The reduction is particularly carried out in steps. A third diameter is measured from the outside of the part of the housing to the radially opposite outside of the part of the housing. A fourth diameter is measured from the outside of the part of the housing to the radially opposite outside of the part of the housing, but with an offset in the axial direction. The third diameter is larger than the fourth diameter. The outside of the part of the housing reduces its distance from the axis of rotation. The reduction is particularly carried out in steps. A gap is formed between the inside of the centrifugal disc and part of the housing.The gap serves as a sealing gap, making it difficult for surrounding media to enter an area located spatially behind the sealing gap. The sealing gap is designed in a Z-shape. The inside of the extension of the centrifugal disc and the outside of the housing section run parallel to each other and alternate their direction together in sections. The sealing gap is thus designed in a labyrinthine manner.

[0015] The stepped design of the sealing gap extends the flow path of incoming liquid media, such as wastewater. The constrictions created in the sealing gap when the direction changes disrupt the flow path and slow down incoming media. During operation, this arrangement creates a siphon effect due to the shaft rotating at high speeds. This creates excess pressure in the sealing gap, making it difficult for media to enter the sealing gap. The described arrangement therefore prevents only a portion of the surrounding media from entering the sealing gap. In the labyrinthine sealing gap, they are slowed down and, if they pass through at all, only at a reduced speed.

[0016] According to the independent claim, a part of the housing has first depressions on an outer side of the housing facing the extension of the centrifugal disc, and an inner side of the extension facing the part of the housing has second depressions, which are in the form of circumferential grooves. Depressions, i.e. recesses, are formed on the part of the housing facing the extension of the centrifugal disc. Recesses are also formed on the side of the extension opposite the part of the housing. In particular, the recesses on the part of the housing are V-shaped in a cross-section through the radial plane in which the axis of rotation also runs. In particular, the recesses on the extension of the centrifugal disc are V-shaped in a cross-section through the radial plane in which the axis of rotation also runs, but rotated by 180° so that the tip of the V-shape points away from the axis of rotation.Viewed three-dimensionally, the recesses are designed as circumferential grooves. The recesses increase the contact area between an inflowing medium and the extension and the part of the housing. The recesses act like breakwaters, reducing the flow velocity of the medium. Furthermore, the depressions concentrate fluids and drain them outward due to gravity.

[0017] In a further development of this, it is proposed that the part of the housing at least partially forms a groove as a fluid channel. The groove can be formed entirely on the part of the housing or only in part. The groove is preferably adjoined by a housing section which projects radially beyond the extension of the centrifugal disc and is inclined away from the extension. The groove is a channel for fluids on the housing. Media, such as dirty water, collect in the groove instead of being pushed further into the gap between the extension and part of the housing and flow out of the bearing assembly along the groove due to gravity.

[0018] Preferably, the sealing ring has at least one second sealing lip, creating a trapping chamber between the first sealing lip and the second sealing lip. Preferably, the second sealing lip does not touch the shaft to prevent frictional wear of the second sealing lip.

[0019] Preferably, a radially outer side of the extension of the centrifugal disc facing away from the part of the housing has recesses.

[0020] In particular, these recesses are designed circumferentially. Specifically, the recesses are designed as V-shaped grooves with the aim of reducing the velocity of incoming media and preventing media, such as dirty water, from entering the sealing gap. Short description of the drawing

[0021] They show: Fig. 1 shows a section of an embodiment of a bearing arrangement in a cross-sectional view; Fig. 2 shows a section of a cross-sectional view of an embodiment of the bearing arrangement according to the invention; Fig. 3 a section of a cross-sectional view of another bearing arrangement, Fig. 4 a section of a cross-sectional view of a further embodiment of the bearing arrangement according to the invention, Fig. 5 a section of a cross-sectional view of a bearing arrangement. Detailed description of the drawing

[0022] Fig. 1 shows a section of a bearing arrangement 1 with a rolling bearing 2 equipped with ball rolling elements 29. The illustration shows a cross-section through a plane in which a rotation axis 3 also runs in the axial direction a. A radial direction r runs perpendicular to this. An axis in the radial direction r spans the plane, also referred to as the radial plane, together with the rotation axis 3. The rolling bearing 2 is arranged between a rotating shaft 4, 31 and a housing 5. Axially offset from the rolling bearing 2, a sealing ring 10 is arranged between the housing 5 and the shaft 4, 31. The sealing ring 10 has a first sealing lip 11 which protrudes on a side facing away from the rolling bearing 2. The sealing ring 10 has a second sealing lip 14 and a third sealing lip 33 which do not make contact with the shaft 4, 31. In addition, the sealing ring 10 has an additional sealing lip 30 which contacts the shaft 4, 31.The sealing ring 10 is arranged on the housing 5, while a flinger 6 is arranged on the shaft 4, 31. The flinger 6 consists of a base with which it sits on the shaft 4, 31, a base body 8 and an extension 7. The flinger 6 extends in the radial direction r away from the shaft 4, 31 beyond the part 12 of the housing 5. The extension 7 of the flinger 6 thus frames the part 12 of the housing 5 all the way around. The part 12 of the housing 5 forms an undercut 13 with the extension 7 of the flinger 6 such that the part 12 overlaps with the extension 7 both in the radial direction r and in the axial direction a. A sealing gap 17 remains between the housing 5 and the flinger 6, which changes direction at least once and is thus designed as a labyrinth seal.The base body 8 of the centrifugal disc 6 has a first catch arm 9 which extends in the direction of the sealing ring 10, wherein the first catch arm 9 overlaps the first sealing lip 11 without contact. During operation, the described bearing arrangement 1 induces an overpressure at the sealing gap 17 upon rotation of the shaft 4, 31 and thus of the centrifugal disc 6 located on the shaft 4, 31 at high speeds. A siphon effect occurs at the sealing gap 17. Dirty water is prevented from entering the interior between the centrifugal disc 6 and the sealing ring 10. If dirty water does penetrate, it is prevented from advancing further by an interaction between the first catch arm 9 and the first sealing lip 11.

[0023] Fig. Figure 2 shows a partial view of a first embodiment of the bearing arrangement 1 according to the invention. This embodiment has a similar arrangement to Fig. 1, with a housing 5, a shaft 4, 31, a sealing ring 10 and a flinger 6 with an extension 7. The sealing ring 10 has a first sealing lip 11 which extends in the direction of the flinger 6. Furthermore, the sealing ring 10 has a non-contact second sealing lip 14, a non-contact third sealing lip 33 and an additional sealing lip 30, wherein the additional sealing lip 30 is tangent to the shaft 4, 31. The flinger 6 is arranged on the shaft 4, 31 and, in addition to a first catch on the 9, has a second catch arm 20 which is inclined in the direction of the sealing ring 10. The first catch arm 9 runs in the axial direction a towards the sealing ring 10 and has a section 27 which runs in the direction of the housing 5. Coming from the direction of the housing 5 towards the shaft 4, 31, the first catch arm 9, the first sealing lip 11 and the second catch arm 20 are arranged alternately.The housing 5 has a part 12 facing the extension 7. The part 12 of the housing 5 forms an overlap with the extension 7 of the centrifugal disc 6 in the axial direction a and in the radial direction r, i.e., an undercut 13. An inner side 15 of the extension 7 facing the housing 5 faces an outer side 16 of the housing 5 at a distance.

[0024] The extension 7 tapers gradually on the inner side 15, so that a first diameter d1, starting from the inner side 15 of the extension 7, is reduced to a diameter d2. Analogously, a diameter d3, starting from the outer side 16 of the housing 5, is reduced to a diameter d4. The sealing gap 17 formed in this way has a Z-shaped profile. This arrangement also creates a siphon effect, and dirty water can be prevented from entering the interior. Any dirty water that does enter is prevented on the one hand by the specially shaped first catch arm 9. On the other hand, the alternating arrangement with the overlap between the first catch arm 9, the first sealing lip 11, and the second catch arm 20 creates a further labyrinth, so that in this embodiment there is a double labyrinth.Through this interlocking of the first catch arm 9 and the second catch arm 20 with the first sealing lip 11, a complex flow path is deliberately created for the medium in order to make it more difficult to penetrate into the critical area.

[0025] Also in Fig. 3 shows a bearing arrangement 1. It shows a housing 5 which circumferentially surrounds a shaft 4, 31. The shaft 4, 31 runs along a rotation axis 3 extending in the axial direction a, and a radial direction r runs perpendicular to the rotation axis 3. The housing 5 has a part 12, which in turn has an end section 19 of the housing 5. A sealing ring 10 is arranged on the housing 5. A first sealing lip 11 extends from a radially extending base body 8 of the sealing ring 10. The first sealing lip 11 initially runs parallel to the rotation axis 3 and then bends such that it runs obliquely away from the rotation axis 3 in the direction of the centrifugal disk 6. In addition, the sealing ring 10 has a second sealing lip 14 and a third sealing lip 33, which do not touch the shaft 4, 31, as well as an additional sealing lip 30, which is tangent to the shaft 4, 31.The first sealing lip 11 strikes a first catching arm 9 of the centrifugal disc 6 almost vertically, the first catching arm 9 and the first sealing lip 11 in, in . Fig. 3, are spaced apart from one another. The centrifugal disc 6 is arranged on the shaft 4, 31 and extends in the radial direction r in the direction of the housing 5, wherein an extension 7 of the centrifugal disc 6 running in the axial direction a encloses the part 12 of the housing 5. The extension 7 has an extension 18 which extends in the radial direction r. At the same time, the housing 5 has an end section 19 which extends in the axial direction a and forms an overlap with the extension 7 of the centrifugal disc 6. An undercut 13 is thus formed in two directions, namely in an axial direction a and a radial direction r, between the extension 7 of the centrifugal disc 6 and the part 12 and the end section 19 of the housing 5. Due to the geometry of the centrifugal disc 6 and the housing 5, a sealing gap 17 is formed which runs in a labyrinth-like manner.This creates a pre-labyrinth that prevents dirty water in particular from entering the interior.

[0026] Fig. 4 discloses a second embodiment of the bearing assembly 1 according to the invention in a cross-section. In this embodiment, the centrifugal disc 6 is arranged on a further shaft 31, which is at least partially surrounded by a shaft 4. In this embodiment, too, an extension 7 of the centrifugal disc 6 extends in the axial direction a and frames a part 12 of a housing 5. Because the housing 5 extends beyond the extension 7 in the radial direction r, an undercut 13 is formed between the extension 7 and the housing 5. A sealing gap 17 remains between the centrifugal disc 6 and the housing 5, which makes entry into the interior difficult.

[0027] The centrifugal disc 6 has a first catch arm 9, which extends in the direction of a sealing ring 10. The sealing ring 10 is arranged on the housing 5 and has a first sealing lip 11, which extends in the direction of the centrifugal disc 6. In addition, the sealing ring 10 has a non-contact second sealing lip 14, a non-contact third sealing lip 33, and an additional sealing lip 30, which contacts the first shaft 4. The extension 7 has an inner side 15, which faces an outer side 16 of the housing 5. Radially opposite, the extension 7 has a radially outer side 25. On the outer side 16 of the part 12 of the housing 5, first recesses 23 are formed, which are V-shaped in the cross-section shown. At the same time, second recesses 24 are formed on the inner side 15 of the centrifugal disc 6, which are V-shaped in cross-section when rotated by 180°.Recesses 26 are also formed on the radially outer side 25 of the extension 7, which are also V-shaped in the cross-section shown. Viewed three-dimensionally, these are channels with a V-shaped cross-section on the inner side 15 and the radially outer side 25 of the extension 7 as well as on the outer side 16 of part 12 of the housing 5. Part 12 of the housing 5 has approximately one half of a groove 28, which is completed in an adjoining housing section 32 by a second half of the groove 28. The adjoining housing section 32 has, in the radial direction beyond the extension 7 of the centrifugal disk 6, a surface which slopes away from the extension 7. The inclined surface of the housing section 32 drains media which collect in the groove 28 back out of the groove 28.The first recesses 23 and the second recesses 24 increase the contact surface with incoming media, such as dirty water. This reduces the flow velocity of any incoming media. The illustrated geometric design of the sealing gap 17 throttles the velocity of a medium. During operation, the bearing assembly 1 rotates, and media that has collected in the first recesses 23 and the second recesses 24 are consistently discharged again due to gravity. The recesses 26 on the radially outer side 25 serve the purpose of collecting media and discharging it again when the centrifugal disc 6 rotates.

[0028] Fig. Figure 5 shows a further bearing assembly 1 with a shaft 4, 31 and a housing 5, wherein a sealing ring 10 is arranged between the shaft 4, 31 and the housing 5. The sealing ring 10 is arranged on the housing 5, while a centrifugal disc 6 is arranged on the shaft 4, 31. An extension 7 of the centrifugal disc 6 is designed in a stepped manner on an inner side 15. Complementarily, the outer side 16 of a part 12 of the housing 5 opposite the extension 7 is also designed in a stepped manner, as in Fig.2. Since part 12 of the housing 5 is spaced from the extension 7 of the centrifugal disc 6, a sealing gap 17 is formed which runs in a labyrinthine manner. Part 12 of the housing 5 and the extension 7 of the centrifugal disc 6 form an undercut 13. This differs in particular from previously illustrated embodiments in that the centrifugal disc 6 has a further catch arm 22 in addition to the first catch arm 9 and the second catch arm 20. At the same time, the sealing ring 10, starting from a base body 8, has a further sealing lip 21 in addition to the first sealing lip 11. Starting from the shaft 4, 31 and leading to the housing 5 in the radial direction r, the following sequence is implemented: a second catch arm 20, a first sealing lip 11, a first catch arm 9, a further sealing lip 21, and a further catch arm 22.In addition to a pre-labyrinth seal formed by part 12 of the housing 5 and the extension 7 of the centrifugal disc 6, a labyrinth seal is also formed inside. The second sealing lip 14 and the third sealing lip 33 form trap chambers. The additional sealing lip 30 forms a barrier as a final safeguard against the penetration of media into critical areas.

[0029] This means that a double seal can be used to prevent disruptive liquids, such as dirty water, from penetrating into the rolling bearing 2 even under extreme conditions, such as very high pressures. List of reference symbols 1 bearing arrangement 2 rolling bearings 3 rotation axis 4 First wave 5 housings 6 centrifugal disc 7 extension 8 basic bodies 9 First tentacle 10 Sealing ring 11 First sealing lip 12 Part of the housing 13 Undercut 14 Second sealing lip 15 Inside of the centrifugal disc 16 Outside of the housing 17 Sealing gap 18 extensions on the spinner disc 19 End section of the housing 20 Second tentacle 21 Additional sealing lip 22 Additional tentacle 23 First deepenings 24 Second wells 25 Radially outer side of the process 26 recesses 27 Section on the first tentacle 28 groove on the housing 29 ball rolling elements 30 Additional sealing lip 31 Further wave 32 Housing section 33 Third sealing lip a Axial direction d1 First diameter d2 Second diameter d3 Third diameter d4 Fourth diameter r Radial direction

Claims

[1] Bearing arrangement (1), comprising - a rolling bearing (2) which is arranged around a rotation axis (3) running in the axial direction (a), - a shaft (4, 31) extending in the axial direction (a), - a housing (5), - a centrifugal disc (6) arranged on the shaft (4, 31), which has an extension (7) extending in the axial direction (a) and a base body (8) extending in the radial direction (r) with a first catch arm (9), which extension (7) surrounds a part (12) of the housing (5) all the way around and at least the part (12) of the housing (5) forms an undercut (13) in the axial direction (a) and in the radial direction (r) with the extension (7) of the centrifugal disc (6), - a sealing ring (10) arranged on the housing (5), which has a first sealing lip (11) extending in the direction of the base body (8) of the centrifugal disc (6), wherein the first catch arm (9) of the centrifugal disc (6) extends towards the sealing ring (10), characterized by in that the extension (7) of the centrifugal disc (6) has a reduction of a first diameter (d1) to a second diameter (d2) on an inner side (15) of the centrifugal disc (6) facing the shaft (4, 31), wherein the housing (5) has a reduction of a third diameter (d3) to a fourth diameter (d4) on an outer side (16) of the housing (5) facing the inner side (15) of the centrifugal disc (6), wherein a sealing gap (17) is formed between the inner side (15) of the centrifugal disc (6) and the outer side (16) of the housing (5). [2] Bearing arrangement according to the preamble of claim 1, characterized bythat the part (12) of the housing (5) which is framed all the way around by the extension (7) has first depressions (23) on an outer side (16) of the housing (5) facing the extension (7) of the centrifugal disc (6), and that an inner side (15) of the extension (7) facing the part (12) of the housing (5) has second depressions (24), which first and second depressions (23) are in the form of circumferential grooves. [3] Bearing arrangement according to claim 2, characterized by that the part (12) of the housing (5) at least partially forms a groove (28) as a fluid channel. [4] Bearing arrangement according to claim 1 or 2, characterized by that the sealing ring (10) has at least one second sealing lip (14). [5] Bearing arrangement according to claim 2, characterized by that a radially outer side (25) of the extension (7) of the centrifugal disc (6) facing away from the part (12) of the housing (5) has circumferential recesses (26).

Images