Electrical coupling unit for the housing feedthrough of high-voltage power current; and electric drive motor

Abstract

The invention relates to an electrical coupling unit (1) for use in a high-voltage electrical system of a motor vehicle, comprising several parallel, electrically decoupled busbars (2), an insert (6) placed and / or clipped onto the busbars (2) on a longitudinal section (3) of each busbar (2) between a first end region (4) and a second end region (5) of the respective busbar (2), a carrier (7) encompassing and receiving the insert (6), and an annular seal (9) made of an elastomeric material applied to an outer surface (8) of the carrier (7) facing away from the insert (6). The insert (6) has a conical outer surface (10) that rests against a complementary inner surface (11) of the carrier (7). The invention also relates to an electric drive motor (16) with this coupling unit (1).

Description

[0001] The invention relates to an electrical coupling unit (also referred to as a connection unit or interface) for use in a high-voltage line (HV line) of a motor vehicle, preferably for use in a supply line of an electric drive machine and thus in the field of e-mobility of motor vehicles.

[0002] Various connector systems are already known from the state of the art, which also have varying degrees of complexity and are used to route a HV cable within the vehicle. Alternatively, screw connections can also be used for contacting within an electrical component. In this case, it is desirable, particularly for manufacturing and assembly reasons, to avoid individual cable harnesses as much as possible and to place electrical drive components directly next to one another and to contact them through them. However, this in turn places additional demands on the sealing and current-carrying capacity of the existing cables.

[0003] An electrical coupling unit according to the preamble of claim 1 is known from each of DE 10 2022 209 683 A1 and DE 20 2010 003 651 U1.

[0004] For further prior art, reference is made to CN 2 17 134 730 U, DE 697 10 481 T2 and DE 10 2015 103 053 A1.

[0005] It is therefore an object of the present invention to provide a coupling unit and an electric drive machine equipped with the coupling unit, wherein the coupling unit has the lowest possible electrical contact resistance, allows simple and robust assembly, compensates for mechanical tolerances, at the same time enables sealing against the environment and is vibration-resistant and capable of EMC protection.

[0006] This is achieved according to the invention with regard to the coupling unit by the subject matter of claim 1 and with regard to the electric drive machine by the subject matter of claim 8.

[0007] Accordingly, an electrical coupling unit for use in a high-voltage line of a motor vehicle, such as a car, truck, bus, or other commercial vehicle, is claimed, which coupling unit has a plurality of parallel, electrically decoupled busbars. The coupling unit further comprises an insert (preferably made of a plastic / elastomer) placed and / or clipped onto a longitudinal section (of the busbars) between a first end region and a second end region of the respective busbar. Furthermore, a carrier is provided which encompasses and receives the insert. In addition, there is a seal which is annular, made of an elastomer material, and applied to an outer side of the carrier facing away from the insert.

[0008] This provides a coupling unit that ensures sufficient tolerance compensation and is easy to install. At the same time, a reliable seal is guaranteed.

[0009] The insert has a conical outer surface that rests against a complementarily shaped inner surface of the carrier. This ensures that the individual elements of the coupling unit are positioned and supported as precisely as possible during assembly.

[0010] Further advantageous embodiments are claimed in the subclaims and explained in more detail below.

[0011] In this regard, it is also advantageous for easy assembly if the insert is positively connected to the carrier.

[0012] If the seal has several circumferential, i.e. ring-shaped, sealing lips / sealing lip segments, the most effective seal possible is guaranteed.

[0013] In this context, it is also useful if the sealing lips differ in their width and / or height.

[0014] Accordingly, it is also advantageous if at least two, more preferably at least three, particularly preferably at least four sealing lips are present.

[0015] If the sealing lips are arranged at different diameters along the conical outer side of the carrier, the strength / fit of the seal in an opening of a housing can be adjusted as precisely as possible.

[0016] In particular, it is expedient if a first sealing lip of the seal is arranged on a diameter which is larger than the diameters on which the further sealing lips of the seal are arranged, wherein the first sealing lip has the greatest width and / or height of all sealing lips of the seal.

[0017] In this context, it is also expedient if a second sealing lip of the seal is arranged on a diameter which is smaller than the diameters on which the further sealing lips of the seal are arranged, wherein the second sealing lip has a greater width and / or height than at least one further sealing lip of the seal.

[0018] It is also advantageous if at least one further, more preferably two further sealing lips, which are smaller in terms of their height and width than the first sealing lip and / or the second sealing lip, are present between the first sealing lip and the second sealing lip.

[0019] Furthermore, the invention relates to an electric drive machine for a motor vehicle drive, having a housing and a high-voltage strand providing drive power and penetrating an outer wall of the housing, wherein a coupling unit according to the invention according to at least one of the previously described embodiments is integrated into the high-voltage strand and is inserted in a fluid-tight manner into an opening in the outer wall.

[0020] The invention will now be explained in more detail below with reference to figures.

[0021] They show: Fig. 1 a perspective view of a coupling unit cut in the longitudinal direction according to a preferred embodiment, which illustrates the design of the existing seal, Fig. 2 a perspective view of the coupling unit according to Fig. 1 in a full view, Fig. 3 a longitudinal section of the coupling unit according to Fig. 1, Fig. 4 a perspective, partially exploded view of the coupling unit of the Fig. 1, and Fig. 5 a schematic representation of an electric drive machine in which the coupling unit is preferably used.

[0022] The figures are merely schematic and serve solely to clarify the invention. The same elements are designated by the same reference numerals.

[0023] The coupling unit 1 according to the invention is in a preferred embodiment in the Fig. 1 to 4 are shown in more detail. In Fig. 5 also shows the preferred application area of ​​the coupling unit 1. According to Fig. 5, the coupling unit 1 is used as an interface in a housing 14 of an electric drive motor 16. In particular, the coupling unit 1 serves to connect several cable sections of a high-voltage line 19 of the motor vehicle to supply the drive motor 16 with electrical energy during operation. Fig. 5 schematically shows a power electronics unit 15 of the drive motor 16, into which the high-voltage line 19 ultimately flows / is connected. It should be noted that the drive motor 16 is typically used as a drive motor in a purely electrically or hybrid-powered motor vehicle and, in further preferred embodiments, can also be a component of a drive train / drive unit of a drive train, for example an electric axle. However, the coupling unit 1 is not limited to this application but can be used universally in various ways for the transmission of HV power current in automobiles. For example, such high-voltage connections capable of carrying high-power current can be created between components such as the battery, converter, electric motor, and charger.

[0024] The coupling unit 1 is in Fig. 5 is inserted into an opening 20 of an outer wall 18 of the housing 14 and, in addition to the purely electrical coupling of the individual line sections of the high-voltage strand 19, also serves to fluidically seal an interior of the housing 14 from an environment.

[0025] In this regard, the Fig.1 to 4 that the coupling unit 1 has a plurality of, here three, busbars 2 that run parallel to one another and form line segments that are electrically decoupled from one another. The busbars 2 protrude with a first end region 4 and a second end region 5 from a surrounding and receiving insert 6 / potting body. Towards a first end region 4 and a second end region 5, each busbar 2 has contact regions 21 that are perforated for further contacting. The insert 6 consequently surrounds the busbars 2 in a longitudinal section 3 of the busbars 2 between the two end regions 4 and 5. The insert 6 is formed in the usual way from an electrically insulating material, such as an elastomer, and is preferably injection-molded directly onto the busbars 2.Alternatively, it is also possible to subsequently insert the busbars 2 into through holes 22 of the prefabricated insert 6 and to clip / lock them in with a positive fit.

[0026] The insert 6 has a conical outer surface 10. The conical outer surface 10, in turn, rests against a conical inner side 11 / inner surface of a carrier 7. The carrier 7 of the coupling unit 1 serves to receive / support a seal 9 towards its outer side 8 / outer surface.

[0027] It should be noted that the support 7 is preferably formed from a metal, such as a metal sheet. The support 7 has a flange 13, which directly forms an axial end. A conically tapered hollow region 17 protrudes from this flange 13. Thus, the hollow region 17 tapers increasingly with increasing distance from the flange 13.

[0028] It should be noted that the insert 6 is preferably positively connected to the support 7, preferably by snapping it into place. The insert 6 is inserted into the hollow area 17 so far that it ultimately ends flush with the support 7 on an end face facing away from the flange 13.

[0029] Finally, the seal 9 is provided on the outer side 8 of the carrier 7 and runs in a ring shape around the hollow area 17.

[0030] With regard to the seal 9, it should be noted that it has several parallel, annular sealing lips 12a to 12d. Because the hollow area 17 is conical, the individual sealing lips 12a, 12b, which are arranged in a row along the hollow area 17, are arranged with different diameters.

[0031] The sealing lip arranged on the largest diameter is referred to as the first sealing lip 12a. This first sealing lip 12a also has the largest width (axial dimension as seen along the busbars 2) and the largest height (dimension as seen perpendicular to the busbars 2) of all sealing lips 12a to 12d. A second sealing lip 12b is arranged on the smallest diameter and here has the second largest width and the second largest height of all sealing lips 12a to 12d. Two further sealing lips 12c and 12d are arranged between the two sealing lips 12a and 12b. These are essentially triangular in shape, while the two first and second sealing lips 12a and 12b have an essentially semicircular cross-section. This results in a total of four sealing lips 12a to 12d, which adjoin one another in the axial direction. The two fourth and third sealing lips 12d and 12c are preferably implemented with the same cross-section.

[0032] It is self-evident that in the preferred area of ​​use, the seal 9 directly seals a gap between a hole bearing area of ​​the opening 20 in the housing 14 and the carrier 7 itself (fluid-tight).

[0033] In other words, according to the invention, the current-carrying metal rail (busbar 2) is inserted / clipped into an insert 6 and then the sealing lips 12a to d made of elastomer material are vulcanized on.

[0034] The sealing geometry enables tolerance compensation, which is also based on the elasticity of the conductor material and the overmolded HV connection.

[0035] The insert 6 can simultaneously satisfy the insulation coordination by inserting barrier ribs if required.

[0036] The tightness of the sensitive power electronics is achieved by the double elastomer sealing lip 12a, 12b and the internal potting.

[0037] This type of connection can be used universally for the transmission of HV power current in automobiles. List of reference symbols 1 coupling unit 2 busbar 3 Longitudinal section 4 first end area 5 second end area 6 Insert 7 carriers 8 Outside 9 Seal 10 Outer surface 11 Inside 12a first sealing lip 12b second sealing lip 12c third sealing lip 12d fourth sealing lip 13 Flange 14 housings 15 Power electronics unit 16 drive machine 17 Hollow area 18 Exterior wall 19 High-voltage line 20 Opening 21 Contact area 22 through hole

Claims

[1] Electrical coupling unit (1) for use in a high-voltage system of a motor vehicle, the electrical coupling unit (1) comprising: several parallel, electrically decoupled busbars (2), an insert part (6) placed and / or clipped onto the busbars (2), in each case on a longitudinal section (3) of a respective busbar (2) between a first end region (4) and a second end region (5) of the respective busbar (2), a carrier (7) encompassing and receiving the insert part (6) and an annular seal (9) made of an elastomer material applied to an outer side (8) of the carrier (7) facing away from the insert (6), characterized by , that the insert part (6) has a conical outer surface (10) which bears against a complementarily shaped inner side (11) of the carrier (7). [2] Coupling unit (1) according to claim 1, characterized by that the insert part (6) is positively connected to the carrier (7). [3] Coupling unit (1) according to claim 1 or 2, characterized by that the seal (9) has several circumferential sealing lips (12a, 12b, 12c, 12d). [4] Coupling unit (1) according to claim 3, characterized by that the sealing lips (12a, 12b, 12c, 12d) differ in their width and / or height. [5] Coupling unit (1) according to claim 3 or 4, characterized by that the sealing lips (12a, 12b, 12c, 12d) are arranged on the conical outer side (8) of the carrier (7) and enclose different diameters of the conical outer side (8) of the carrier (7). [6] Coupling unit (1) according to one of claims 3 to 5, characterized by , that the seal (9) has at least three sealing lips (12a, 12b, 12c, 12d), a first sealing lip (12a) of the seal (9) encloses a diameter of the conical outer side (8) of the carrier (7) which is larger than those diameters of the conical outer side (8) of the carrier (7) which are enclosed by the further sealing lips (12b, 12c, 12d) of the seal (9), and the first sealing lip (12a) has the greatest width and / or height of all sealing lips (12a, 12b, 12c, 12d) of the seal (9). [7] Coupling unit (1) according to one of claims 3 to 6, characterized by , that the seal has at least three sealing lips (12a, 12b, 12c, 12d), a second sealing lip (12b) of the seal (9) encloses a diameter of the conical outer side (8) of the carrier (7) which is smaller than those diameters of the conical outer side (8) of the carrier (7) which are enclosed by the further sealing lips (12a, 12c, 12d) of the seal (9), and the second sealing lip (12b) has a greater width and / or height than at least one further sealing lip (12c, 12d) of the seal (9). [8] Electric drive machine (16) for a motor vehicle drive, with a housing (14) and a high-voltage strand (19) providing a drive power and penetrating an outer wall (18) of the housing (14), wherein a coupling unit (1) according to one of claims 1 to 7 is integrated into the high-voltage strand (19) and is inserted in a fluid-tight manner into an opening (20) in the outer wall (18).

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