Seal assembly and use thereof

Abstract

The seal assembly comprises a current collecting rail (1) with at least one electrical conductor path (2.1, 2.2, 2.3, ...) and a two-component component (3), the two-component component (3) comprising a support part (4) made of a tough material and a seal body (5) made of a rubber-elastic sealing material bonded to the support part (4), the seal body (5) tightly surrounding the electrical conductor path (2.1, 2.2, 2.3, ...) without adhesion and under an elastic preload.

Description

[Technical Field]

[0001] The present invention relates to a seal assembly and the use of the seal assembly, which comprises a current collecting rail with at least one electrical conductor track, the conductor track being sealed against a support part by a seal body. [Background technology]

[0002] An increasing number of electric vehicles use oil-cooled electric motors, which place high demands on their sealing properties, especially due to the power electronics of further electrical components, such as the power electronics of the inverter.

[0003] In addition, electric vehicles use current collector rails, so-called bus bars, which contain electrical conductor tracks made of copper or aluminum sheet metal and are stamped and then bent to the desired dimensions. These copper or aluminum sheets have a rectangular electrical conductor cross section due to their manufacturing process, but this does not provide a satisfactory standard sealing performance because the corners of the stamped sheet metal do not allow the standard sealing material to be tightly compressed.

[0004] For this reason, in the prior art, rectangular conductor tracks are also injection-molded with a thermoplastic or thermosetting material to form a tight seal. If necessary, the conductor tracks are additionally glued with an adhesive. However, this does not usually result in a lasting, good seal. The seal results are only satisfactory initially, and even after a short period of use, they often exhibit leaks, especially when the sealing area is exposed to temperature changes. The reason for this is the difference in the thermal expansion coefficients of the electrical conductor tracks and the sealing material surrounding them. The different thermal expansion coefficients of these two materials lead to increased mechanical stresses in the boundary layer, which in turn leads to the aforementioned leaks.

[0005] Another drawback is that the electrical conductor tracks and the seals surrounding them cannot be separated from each other without destruction, and in repair cases the entire unit consisting of the electrical conductor tracks and the seals must be replaced, which is unsatisfactory both in terms of environmental protection and in terms of responsible resource and economic management. Summary of the Invention [Problem to be solved by the invention]

[0006] The problem on which the invention is based is to further develop a sealing assembly of the type mentioned at the outset in such a way that the above-mentioned disadvantages are avoided.

[0007] In particular, the seal assembly should have consistently good operating characteristics over extended periods of use.

[0008] The electrical conductor tracks and seals should be separately replaceable from one another as required and recyclable by type.

[0009] Additionally, the use of a seal assembly should be indicated. [Means for solving the problem]

[0010] This problem is solved according to the invention by the features of claims 1 and 14. With regard to advantageous configurations of the seal assembly, reference is made to the claims which directly or indirectly cite claim 1.

[0011] To achieve this object, a seal assembly is provided, which includes a current collecting rail with at least one electrical conductor path and a two-component component, which includes a support part made of a tough material and a seal body made of a rubber-elastic sealing material bonded to the support part in a material-bonding manner, the seal body tightly surrounding the electrical conductor path under an elastic preload without adhesion.

[0012] The two-component sealing body can be made of a conventional rubber-elastic sealing material. Rubber-elastic sealing materials are available in many specifications at low cost, allowing the entire sealing assembly to be manufactured simply and inexpensively. The sealing body tightly surrounds the electrical conductor tracks under an elastic preload without adhesion. Therefore, the sealing body and the electrical conductor tracks can be replaced separately from each other as needed. In particular, the reusability of any practical length of the electrical conductor tracks, which are made of expensive materials and are not actually subjected to wear during their use, is an advantage that should be emphasized.

[0013] In an advantageous embodiment, the support can be made of a tough plastic, which is preferably electrically insulating. The advantage here is that the two-component component can be manufactured easily and inexpensively and has a low weight. The electrically insulating nature of the support part has the advantage that the housing, which must be manufactured separately and in which the two-component component is usually fixed, does not need to be electrically insulating.

[0014] The support is formed substantially L-shaped in cross section and has an axial flange and a radial flange, the axial flange extending parallel to the electrical conductor path and surrounding the electrical conductor path at a radial distance, and at least one inner sealing lip of the sealing body is arranged in the gap formed by the distance, and the inner sealing lip tightly surrounds the outer peripheral surface of the electrical conductor path under an elastic preload without contacting it.

[0015] More preferably, two inner sealing lips arranged in series can be used in order to further increase the sealing reliability.

[0016] At least one outer sealing lip may be arranged on the axial flange diametrically opposite the inner sealing lip, which outer sealing lip seals against a housing in which the two-component component is fixed.

[0017] According to a first embodiment, it can be provided that the inner and outer sealing lips merge into one another and are formed in one piece, whereby the production of the two-component component is advantageously particularly simple and cost-effective.

[0018] The inner and outer sealing lips are preferably made of an electrically insulating sealing material, and in particular if the carrier part is also made of an electrically insulating material, the electrical conductor tracks of the current collecting rail and the housing to which the two-component component is fixed are effectively electrically insulated from one another.

[0019] According to a second embodiment, the inner and outer sealing lips can be individually designed and arranged without contact with each other. Advantageously, the inner and outer sealing lips can be functionally individualized. The material properties of the sealing lips can be well adapted to their respective functions.

[0020] At least the inner sealing lip can be made of an electrically insulating sealing material. It is not necessary for the outer sealing lip to also be made of an electrically insulating sealing material, provided that the inner sealing lip seals the electrical conductor paths and prevents contact with the carrier parts. It is also possible to use sealing materials that do not have a particularly high electrical resistance but that, for example, are particularly oil-resistant and therefore provide a particularly durable and reliable seal.

[0021] Additional sealing of the two-component component relative to the housing to which it is fixed can be achieved by the radial flange having at least one axial sealing lip extending axially toward the outer sealing lip and substantially along the outer circumferential surface of the support part. In such a case, the two-component component is sealed by cooperation of the axial sealing lip and the outer sealing lip. The axial sealing lip and the outer sealing lip seal the opening of the housing, in which the two-component component is located, against the surrounding environment.

[0022] In an advantageous embodiment, the electrical conductor tracks may have a circular or elliptical cross section. The advantage here is that, unlike electrical conductor tracks made of stamped sheet metal, electrical conductor tracks with a circular or elliptical cross section do not have corners or stamping burrs resulting from the stamping process, which allows for a firm compression of the sealing material. The circular or elliptical cross section of the electrical conductor tracks prevents damage to the inner sealing lip even in the case of a relatively large elastic preload.

[0023] The support part can have at least one fastening hole in which a stress-limiting element is arranged. The support part can be screwed, for example, to a housing. For this purpose, a screw first passes through the fastening hole and is screwed into the housing. To prevent damage to the support part when screwing the screw into the housing due to an excessively high tightening torque, a stress-limiting element, which can be formed, for example, by a stress-limiting ring, is provided. This prevents undesirably high stresses that would otherwise lead to the destruction of the support part.

[0024] Alternatively, the seal assembly may include a liquid-cooled electronic component with a housing having a built-in opening within which the two-component component is closely positioned.

[0025] The electronic component may be formed by an electric motor.

[0026] As already explained at the beginning, particularly in the case of oil-cooled electric motors in electric vehicles, it is necessary to reliably seal the sensitive power electronics, for example the power electronics of the inverter.

[0027] Additionally, the present invention relates to the use of a seal assembly as described above for sealing a current collecting rail of a liquid-cooled electronic component.

[0028] The above-described seal assembly can be manufactured easily and inexpensively. In possible repair cases, the electrical conductor tracks can always be reused due to the unattached assignment of the electrical conductor tracks to the inner seal. For this purpose, the electrical conductor tracks are simply pulled out from the inner seal, the previous carrier part and the previous seal body, i.e., the two-component component, are exchanged for a corresponding new pre-mounted unit, and the electrical conductor tracks are reattached to the seal body.

[0029] The seal assembly also has a reduced part count and installation can be performed with a reliable process because installation of a separately manufactured seal ring is not required.

[0030] An embodiment of a seal assembly according to the present invention will now be described in more detail with reference to FIGS. [Brief explanation of the drawings]

[0031] [Figure 1] FIG. 1 is a perspective view of a portion of an embodiment of a seal assembly. [Figure 2] FIG. 2 is a cross-sectional view of the seal assembly shown in FIG. 1. DETAILED DESCRIPTION OF THE INVENTION

[0032] 1 and 2 show an embodiment of a seal assembly according to the present invention.

[0033] In this embodiment, the current collector rail 1 includes three electrical conductor tracks 2.1, 2.2, and 2.3, each with a circular cross section. The electrical conductor tracks 2.1, 2.2, and 2.3 are surrounded by a two-component component 3, which includes a carrier part 4 and a sealing body 5. In this embodiment, the carrier part 4 is made of a tough, electrically insulating plastic, and the sealing body 5 is made of a rubber-elastic sealing material. The carrier part 4 and the sealing body 5 form a pre-mounted unit and are materially connected to each other.

[0034] The liquid-cooled electronic component 14, shown diagrammatically, is formed by an oil-cooled electric motor for an electric vehicle and includes a housing 15. The housing 15 has an installation opening 16 for a two-component component 3. The two-component component 3 is tightly arranged in the installation opening 16 of the housing 15. The two-component component 3 is screwed into the housing 15. The support part 4 has two fastening holes 12.1, 12.2 in which annular stress-limiting elements 13.1, 13.2, for example made of a metallic material, are arranged, respectively. This protects the relatively sensitive material of the support part 4 from excessively high tightening torques that could destroy the support part 4 during installation of the support part 4 in the housing 15.

[0035] Figure 2 shows a cross-sectional view of the seal assembly shown in Figure 1. It can be seen that the support body 4 is substantially L-shaped in cross section and has an axial flange 6 and a radial flange 7. The axial flange 6 extends parallel to the electrical conductor tracks 2.1, 2.2, and 2.3, while the radial flange 7 extends perpendicular to the electrical conductor tracks 2.1, 2.2, and 2.3. The axial flange 6 is substantially completely surrounded by the sealing material of the seal body 5, and is completely surrounded on the inside by inner sealing lips 9.1 and 9.2 and on the outside by an outer sealing lip 10.

[0036] In the illustrated embodiment, the inner sealing lips 9.1, 9.2 and the outer sealing lip 10 are integrally connected to one another and consist of the same electrically insulating sealing material. For many applications, this type of integrally connected, uniform construction is well suited and can be manufactured simply and inexpensively.

[0037] An axial sealing lip 11, which likewise merges integrally with one another and is formed in the same material as the outer sealing lip 10 and the inner sealing lip 9.1, 9.2, is arranged on the radial flange 7 of the carrier part 4 and is bead-shaped and curved axially towards the outer sealing lip 10. The axial sealing lip 11 seals against the end face of the housing 15, while the outer sealing lip 10 seals against the circumferential boundary of the installation opening 16.

[0038] The sealing body 5 tightly surrounds the electrical conductor tracks 2.1, 2.2, 2.3, respectively, without adhesion and under elastic preload, so that, if necessary, the electrical conductor tracks 2.1, 2.2, 2.3 can be easily and unbreakably separated from the sealing body 5.

Claims

1. 1. A seal assembly comprising: a current collecting rail (1) with at least one electrical conductor track (2.1, 2.2, 2.3, ...); and a two-component component (3), the two-component component (3) comprising a carrier part (4) made of a tough material and a seal body (5) made of a rubber-elastic sealing material material bonded to the carrier part (4), the seal body (5) tightly surrounding the electrical conductor track (2.1, 2.2, 2.3, ...) without adhesion and under an elastic preload.

2. 2. The seal assembly according to claim 1, wherein the support (4) is made of electrically insulating plastic.

3. 3. The seal assembly according to claim 1, wherein the support (4) is substantially L-shaped in cross section and comprises an axial flange (6) and a radial flange (7), the axial flange (6) extending parallel to the electrical conductor tracks (2.1, 2.2, 2.3, ...) and surrounding the electrical conductor tracks (2.1, 2.2, 2.3, ...) at a radial distance therefrom, and wherein at least one inner sealing lip (9.1, 9.2, ...) of the sealing body (5) is arranged in a gap (8) formed by the gap, the inner sealing lip (9.1, 9.2, ...) tightly surrounding the outer circumferential surface of the electrical conductor tracks (2.1, 2.2, 2.3, ...) without contact and under an elastic preload.

4. 4. The seal assembly according to claim 3, wherein at least one outer sealing lip (10) is arranged on the axial flange (6) radially opposite the inner sealing lips (9.1, 9.2, ...).

5. 5. The seal assembly according to claim 3, wherein the inner sealing lip (9.1, 9.2, ...) and the outer sealing lip (10) merge into one another and are formed of the same material.

6. 6. The seal assembly according to claim 3, wherein the inner sealing lip (9.1, 9.2, ...) and the outer sealing lip (10) consist of an electrically insulating sealing material.

7. 5. The seal assembly according to claim 3, wherein the inner sealing lip (9.1, 9.2, ...) and the outer sealing lip (10) are each produced separately from one another and are allocated to one another in a non-contact manner.

8. 8. The seal assembly according to claim 7, wherein at least the inner sealing lips (9.1, 9.2, ...) consist of an electrically insulating sealing material.

9. 9. The seal assembly according to claim 1, wherein the radial flange (7) has at least one axial sealing lip (11) extending axially in the direction of the outer sealing lip (10) and substantially along the outer circumferential surface of the support part (4).

10. 10. The seal assembly according to claim 1, wherein the electrical conductor tracks (2.1, 2.2, 2.3, ...) have a circular or elliptical cross section.

11. 10. The seal assembly according to claim 1, wherein the support part (4) has at least one fastening hole (12.1, 12.2, ...) in which a stress limiting element (13.1, 13.2, ...) is arranged.

12. 12. The seal assembly according to claim 1, further comprising a liquid-cooled electronic component (14) with a housing (15), the housing (15) having an integrated opening (16) in which the two-component component (3) is closely arranged.

13. The seal assembly of claim 12, wherein the electronic component (14) is formed by an electric motor.

14. Use of a seal assembly according to any one of claims 1 to 13 for sealing a current collector rail (1) of a liquid-cooled electronic component (14).

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