Sealing device and application thereof

Abstract

The invention relates to a sealing device, comprising a busbar (1) comprising at least one electrical conductor (2.1, 2.2, 2.3,...), and a two-component component (3), which has a support part (4) made of a tough material and a sealing body (5) made of a rubber-elastic sealing material, which is integrally bonded to the support part (4), the sealing body (5) surrounds the electrical conductors (2.1, 2.2, 2.3,...) in a non-adhesive and elastic prestress manner.

Description

Technical Field

[0001] The invention relates to a sealing arrangement and its use, wherein the sealing arrangement comprises a busbar with at least one electrical conductor, which is sealed relative to a carrier by a sealing body. Background Art

[0002] Oil-cooled electric motors are increasingly being used in electric vehicles, placing increased demands on the sealing of their power electronics, in particular relative to other electrical components, such as the power electronics of an inverter.

[0003] Furthermore, electric vehicles use busbars, so-called busbars, which have electrical conductors made of copper or aluminum sheets that are punched out and subsequently bent to the desired dimensions. These copper or aluminum sheets, due to their production, have rectangular conductor cross-sections that are less than satisfactory for standard seals, as the corners of the punched-out sheets do not allow for reliable compression of the sealing material of standard seals.

[0004] For this reason, it is also known in the prior art to seal the rectangular conductors with a thermoplastic or thermosetting material by injection molding. The conductors are additionally bonded using adhesives as needed. However, this does not usually result in a long-lasting, good sealing effect. The sealing effect is only satisfactory initially and often shows signs of leaking after a short period of use, especially when the seal is exposed to temperature fluctuations. This is due to the different coefficients of thermal expansion of the conductor and the sealing material surrounding it. These different coefficients of thermal expansion of the two materials lead to increased mechanical stresses in the boundary layer and, therefore, to the aforementioned leaks.

[0005] In addition, it is disadvantageous that the conductor and the sealing device surrounding the conductor cannot be disconnected from each other without destruction. In the case of maintenance, the unit consisting of the conductor and the sealing device must be replaced as a whole, which is not very satisfactory with regard to good environmental protection, responsible treatment of resources and economic aspects. Summary of the Invention

[0006] The object of the present invention is to further develop a sealing device of the type mentioned at the outset in such a way that the disadvantages mentioned above are avoided.

[0007] In particular, the sealing device should have consistently good performance characteristics over a long service life.

[0008] The electrical conductor and the seal should be replaceable separately from one another as required and recyclable in their pure form.

[0009] Furthermore, the use of the sealing device should be shown.

[0010] This object is achieved according to the invention by the features of claim 1 and claim 14. With regard to advantageous embodiments of the sealing device, reference is made to the claims which directly or indirectly refer to claim 1.

[0011] In order to achieve this object, a sealing device is provided, which has a busbar comprising at least one electrical conductor and a two-component component, the two-component component having a carrier made of a tough material and a sealing body made of an elastic rubber sealing material, the sealing body being materially connected to the carrier, the sealing body surrounding the electrical conductor in a non-adhesive manner and under elastic prestressing.

[0012] The sealing body of the two-component component can be made of a conventional rubber-elastic sealing material. Rubber-elastic sealing materials are available in a variety of sizes and at low cost, making the sealing device simple and cost-effective to manufacture overall. The sealing body seals the electrical conductor without adhesion and under elastic prestress. Therefore, the sealing body and the electrical conductor can be replaced separately as needed. This is particularly advantageous because the electrical conductor, which is made of expensive materials and experiences virtually no wear during its service life, can be reusable for virtually any length of time.

[0013] According to an advantageous embodiment, the carrier can be made of a tough, preferably electrically insulating plastic. Advantageously, the two-component component can be manufactured simply and cost-effectively and has only a low weight. The electrically insulating nature of the carrier has the advantage that no separate electrical insulation, which must be manufactured and mounted relative to the housing, to which the two-component component is typically fixed, is required.

[0014] The carrier body can be designed to be essentially L-shaped when viewed in cross section, comprising an axial flange and a radial flange, wherein the axial flange extends parallel to the electrical conductor and surrounds the electrical conductor at a radial distance, wherein at least one inner sealing lip of the sealing body is arranged in a gap formed by the distance, and the inner sealing lip surrounds the outer circumference of the electrical conductor in a non-adhesive manner and under elastic prestressing.

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

[0016] At least one outer sealing lip can be provided on the side of the axial flange facing away radially from the inner sealing lip. This outer sealing lip seals against a housing to which the two-component component is fixed.

[0017] According to a first embodiment, it can be provided that the inner sealing lip and the outer sealing lip transition into each other in one piece and are formed of the same material. Advantageously, the manufacture of the two-component component is thus particularly simple and inexpensive.

[0018] The inner and outer sealing lips are preferably made of an electrically insulating sealing material. In particular, when the carrier is also made of an electrically insulating material, the electrical conductors of the busbar and the housing, to which the two-component member is fixed, are effectively electrically insulated from each other.

[0019] According to a second embodiment, it can be provided that the inner and outer sealing lips are each produced separately from one another and are assigned to one another without contact. Advantageously, the inner and outer sealing lips can each be individually customized in terms of functionality. 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. If the electrical conductor is sealed by the inner sealing lip and contact with the carrier is prevented by the inner sealing lip, it is not absolutely necessary for the outer sealing lip to also be made of an electrically insulating sealing material. Sealing materials that do not have a particularly high electrical resistance but nonetheless enable a particularly durable and reliable seal, for example because they are particularly oil-resistant, can also be used.

[0021] Additional sealing of the two-component component relative to the housing to which it is fixed can be achieved by providing the radial flange with at least one axial sealing lip, which extends axially in the direction of the outer sealing lip and substantially along the outer circumference of the carrier. In this case, the two-component component is sealed by the combined action 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 arranged, from the surroundings.

[0022] According to an advantageous embodiment, the conductor can have a round or oval cross section. Advantageously, in contrast to conductors formed from punched sheet metal, the conductor has no corners or process-related punching burrs, thereby enabling reliable compression of the sealing material. Even with high elastic prestressing, the round or oval cross section of the conductor does not damage the inner sealing lip.

[0023] The support component can have at least one fastening hole, in which the force-limiting element is arranged. The support component can be screwed to the housing, for example. To this end, a screw is first inserted through the fastening hole and screwed into the housing. To prevent damage to the support component due to excessive tightening torque of the screw when tightening it to the housing, a force-limiting element, which can be formed, for example, by a force-limiting ring, is provided. This prevents undesirably high forces that could damage the support component without the force-limiting element.

[0024] Furthermore, the sealing arrangement can include a liquid-cooled electrical component having a housing, wherein the housing has an installation opening in which the two-component component is arranged in a sealing manner.

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

[0026] As already mentioned at the outset, particularly in oil-cooled electric motors in electric vehicles, it is necessary to reliably seal sensitive power electronics, such as the power electronics of an inverter.

[0027] The present invention further relates to the use of a sealing arrangement as described above for sealing busbars of liquid-cooled electrical components.

[0028] The aforementioned sealing device is simple and cost-effective to manufacture. In a possible repair situation, the electrical conductor can always be reused by disposing the electrical conductor and the inner sealing device in a non-adherent manner. To do this, the electrical conductor is simply pulled out of the inner sealing device, the previous carrier, i.e., the two-component component, including the previous sealing body is replaced with a corresponding new preassembled unit, and the electrical conductor is reassembled in the sealing body.

[0029] The sealing device also has a structure with few components. The assembly can be carried out in a process-reliable manner, since no separately manufactured sealing ring needs to be assembled. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Then with the help of Figure 1 and 2 An embodiment of the sealing device according to the present invention is further explained.

[0031] These figures are schematically shown:

[0032] Figure 1 A perspective view showing a portion of one embodiment of a sealing device;

[0033] Figure 2 Show Figure 1 Cross-section of the sealing device. DETAILED DESCRIPTION

[0034] exist Figure 1 and2 An embodiment of a sealing device according to the present invention is shown in FIG.

[0035] In this exemplary embodiment, busbar 1 has three electrical conductors 2.1, 2.2, and 2.3, each of which has a round cross-section. Electrical conductors 2.1, 2.2, and 2.3 are enclosed by a two-component component 3 having a carrier 4 and a seal 5. In this exemplary embodiment, carrier 4 is made of a tough, electrically insulating plastic, while seal 5 is made of a rubber-elastic sealing material. Carrier 4 and seal 5 form a preassembled unit and are integrally bonded to one another.

[0036] The schematically shown liquid-cooled electrical component 14 is formed by an oil-cooled electric motor for an electric vehicle and has a housing 15 with an installation opening 16 for a two-component component 3. The two-component component 3 is sealingly arranged in the installation opening 16 of the housing 15. The two-component component 3 is screwed to the housing 15. Two fastening holes 12.1 and 12.2 are provided in the carrier 4, in which are respectively arranged annular force limiting elements 13.1 and 13.2, for example made of a metallic material. This protects the relatively sensitive material of the carrier 4 from excessive tightening torques that could damage the carrier 4 during assembly of the carrier 4 on the housing 15.

[0037] exist Figure 2 Shown in cross section Figure 1 The sealing device is shown here. It can be seen that the carrier body 4 is essentially 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 conductors 2.1, 2.2, 2.3, while the radial flange 7 extends perpendicularly thereto. The axial flange 6 is essentially completely surrounded by the sealing material of the sealing body 5 and is surrounded on the inside by the inner sealing lips 9.1, 9.2 and on the outside by the outer sealing lip 10.

[0038] In the embodiment shown, the inner sealing lips 9.1, 9.2 and the outer sealing lip 10 merge into one another in one piece and are made of the same electrically insulating sealing material. For most applications, such a one-piece transition into one another and a uniform material configuration is well suited and can be manufactured simply and cost-effectively.

[0039] An axial sealing lip 11, which likewise transitions into one another in one piece and is formed of the same material as the outer sealing lip 10 and the inner sealing lips 9.1, 9.2, is arranged on the radial flange 7 of the carrier 4 and projects axially forward in the shape of a ridge in the direction of the outer sealing lip 10. The axial sealing lip 11 seals the end face of the housing 15, while the outer sealing lip 10 seals the peripheral boundary of the installation opening 16.

[0040] The sealing body 5 surrounds the electrical conductors 2.1, 2.2, 2.3 in a sealing manner without adhesion and under elastic prestressing. The electrical conductors 2.1, 2.2, 2.3 can therefore be easily and non-destructively released from the sealing body 5 as required.

Claims

1. A sealing device comprising a busbar (1) comprising at least one electrical conductor (2.1, 2.2, 2.3, ...) and a two-component component (3), the two-component component comprising a carrier (4) made of a tough material and a sealing body (5) made of a rubber-elastic sealing material, the sealing body being connected to the carrier (4) in a material-locking manner, wherein: The sealing body (5) surrounds the electrical conductor (2.1, 2.2, 2.3, . . . ) in a non-adhesive and sealing manner under elastic prestressing.

2. The sealing device according to claim 1, characterized in that The carrier (4) is made of electrically insulating plastic.

3. The sealing device according to claim 1, wherein: The carrier (4) is essentially L-shaped when viewed in cross section and comprises an axial flange (6) and a radial flange (7), wherein the axial flange (6) extends parallel to the electrical conductor (2.1, 2.2, 2.3, ...) and surrounds the electrical conductor at a radial distance, 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 distance, and the inner sealing lip surrounds the outer circumference of the electrical conductor (2.1, 2.2, 2.3, ...) in a non-adhesive manner and under elastic prestressing in a sealing manner.

4. The sealing device according to claim 3, characterized in that At least one outer sealing lip (10) is arranged on a side of the axial flange (6) facing away radially from the inner sealing lips (9.1, 9.2, . . . ).

5. The sealing device according to claim 3 or 4, characterized in that The inner sealing lips (9.1, 9.2, . . .) and the outer sealing lip (10) merge into one another in one piece and are formed of a uniform material.

6. The sealing device according to any one of claims 3 to 5, characterized in that The inner sealing lips (9.1, 9.2, . . . ) and the outer sealing lip (10) are made of an electrically insulating sealing material.

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

8. The sealing device according to claim 7, characterized in that At least the inner sealing lips (9.1, 9.2, . . .) are made of an electrically insulating sealing material.

9. The sealing device according to any one of claims 1 to 8, characterized in that The radial collar (7) has at least one axial sealing lip (11), which extends axially in the direction of the outer sealing lip (10) and substantially along the outer circumference of the carrier (4).

10. The sealing device according to any one of claims 1 to 9, characterized in that The electrical conductors (2.1, 2.2, 2.3, . . .) have a round or oval cross section.

11. The sealing device according to any one of claims 1 to 9, characterized in that The carrier (4) has at least one fixing hole (12.1, 12.2, . . . ) in which a force limiting element (13.1, 13.2, . . . ) is arranged.

12. The sealing device according to any one of claims 1 to 11, characterized in that The sealing device further comprises a liquid-cooled electrical component (14) comprising a housing (15), wherein the housing (15) has an installation opening (16) in which the two-component component (3) is arranged in a sealing manner.

13. The sealing device according to claim 12, characterized in that The electric component (14) is formed by an electric motor. 14 . Use of the sealing device according to claim 1 for sealing a busbar ( 1 ) of a liquid-cooled electrical component ( 14 ).

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