Electrical contacting means and method for producing an electrical contacting means

Abstract

The invention relates to an electrical contacting means (1), in particular for use within a motor vehicle (2), comprising a plurality of busbars (3) which are surrounded at least in portions by a first electrically insulating plastic (4) such that handling and / or operation of the contacting means (1) is possible without the risk of electric shock, wherein a second electrically insulating plastic (5) is arranged at least in portions between the busbars (3) and the first plastic (4), the second plastic bearing against the busbars (3) on one side and against the first plastic (4) on the other side, wherein the first plastic (4) has a higher hardness than the second plastic (5).

Description

[0001] Electrical contact means and

[0002] Method for producing an electrical contacting means

[0003] The present invention relates to an electrical contacting means, in particular for use within a motor vehicle, comprising a plurality of busbars, which are at least partially encompassed by a first electrically insulating plastic material in such a way that handling and / or operation of the contacting means is possible without the risk of electric shock. The invention further relates to a method for producing an electrical contacting means.

[0004] In electric vehicles, the use of plastic-to-metal components is widespread, such as in electrical connectors such as connectors that transmit electrical signals or transmit high power. These electrical connectors often play a crucial role as connecting elements between sensitive control or power electronics and areas in the vehicle exposed to moisture or oil. To protect the sensitive electronic components from harmful media, it is therefore essential that these components are properly sealed.

[0005] Several technologies and methods have been developed to improve sealing, particularly at the contact points between plastic and metal in electrical contact devices. The solution described in patent application DE102012202004A1, for example, is based on a type of positive locking, which mechanically improves the bond between the materials.

[0006] Despite the various existing technologies and approaches, the sealing of plastic-to-metal components in such electrical contacting devices remains a challenge. A key problem is the different thermal expansion between plastic and metal. Over the course of the component's lifetime or during durability tests, in which the components are heated and cooled over multiple cycles, the metal and plastic within a contacting device can separate. This separation leads to the formation of small gaps through which harmful media can penetrate. This problem is further exacerbated by the capillary effect, which further increases the risk of media penetration and impairs the functionality and service life of the electrical contacting device and / or the electronic components in motor vehicles.

[0007] Current technologies do not always provide a reliable and lasting solution to this problem, as they are often unable to effectively manage the effects of repeated thermal cycles that may occur during the lifetime of the vehicles.

[0008] The object of the invention is therefore to provide an electrical contacting device that is highly and reliably impermeable to media penetration and can be manufactured cost-effectively. Furthermore, the object of the invention is to implement a method for producing an electrical contacting device that enables cost-effective production of an electrical contacting device with a high degree of impermeability and reliability.

[0009] This object is achieved by an electrical contacting means, in particular for use within a motor vehicle, comprising a plurality of busbars which are encompassed at least in sections by a first electrically insulating plastic in such a way that handling and / or operation of the contacting means is possible without the risk of an electric shock, wherein at least in sections between the busbars and the first plastic a second electrically insulating plastic is arranged, which on the one hand rests on the busbars and on the other hand on the first plastic, wherein the first plastic has a higher hardness than the second plastic.

[0010] This provides the advantage that the different plastics provide an improved connection technology for plastic-metal components within electrical contacting devices, which is capable of maintaining a high level of tightness, even under conditions of repeated thermal cycles and varying thermal expansion of the materials used. The electrical contacting device according to the invention, through the use of the different plastics, is capable of effectively preventing the formation of microgaps and the penetration of harmful media into or through the electrical contacting device, thus improving the reliability and service life of the electronic components and / or the contacting device.

[0011] The first plastic can preferably be designed as a housing for the electrical contacting means. The plastic housing can, in particular, be provided on the inside with structured surfaces or microstructures that can contribute to improving handling and also increasing surface roughness, in particular to improve adhesion of the second plastic to such structures. In principle, it is possible to design the housing in one piece or in multiple pieces. Furthermore, the housing can preferably also be equipped with integrated fastening elements or mechanisms such as snap, screw, or bayonet locks to enable simple, secure, and tool-free assembly and disassembly of the contacting means on an electrical component or of the housing components on or among each other.The housing may also be divided into several compartments that isolate the busbars, various electronic components and / or connections from each other in order to prevent interference or short circuits between the various parts of the contacting means.

[0012] The first plastic can preferably be selected from the group of thermoplastics, particularly also for forming an electrically insulating plastic housing for the contacting means, comprising in particular polycarbonate (PC), polyethylene (PE), polypropylene (PP) and ABS (acrylonitrile butadiene styrene) or the group of polyetherimides (PEI). It can also be preferred for the first plastic to be a fiber-reinforced plastic, which is preferably reinforced with one or more fibers selected from the group of glass fibers, carbon fibers and / or aramid fibers in order to increase the structural integrity and mechanical strength, for example of a housing molded from the first plastic. The second plastic can preferably be molded as a sealing element of the electrical contacting means.The sealing plastic can preferably have elastic and flexible properties to adapt to different surface shapes and structures, thus ensuring improved sealing. In conjunction with its geometric shape, this can also give the second plastic self-sealing properties to automatically repair minor damage or leaks during use, thus extending the service life of the contacting device. The sealing plastic can also contain special adhesion promoters or additives that improve the adhesion between the sealing element and the metal or plastic part of the contacting device to further reduce the likelihood of leaks or seal failure.

[0013] The contacting device can also preferably be designed modularly to easily adapt to different application scenarios. This modularity would enable versatile application and ensure compatibility with a wide range of electrical systems and components.

[0014] The second plastic and the first plastic can also be formed as a common component, so that, for example, the first plastic forms an electrically insulating housing for the contacting means, while the second plastic functions as a sealing element arranged on this housing. The contacting means can thus be equipped with one or more integrated sealing elements that prevent the penetration of moisture, dust, and other contaminants. This allows, in particular, simplified assembly of the contacting means, for example by inserting the busbars into the housing formed by the first plastic and subsequently closing the housing, whereby the sealing elements formed by the second plastic wrap around the busbars and thus seal them off from the environment.Preferably, this embodiment may utilize two-component injection molding technology, wherein the second plastic is applied directly to the housing as a sealing element during the manufacturing process, enabling an integrated, seamless seal that further increases the reliability of the electrical connection.

[0015] It would also be conceivable for the busbars and the second plastic to form a common component and then, for example, be inserted into a housing formed from the first plastic, which could also contribute to simplifying the assembly of the electrical contacting device. This embodiment can also preferably utilize two-component injection molding technology, with the second plastic being applied directly to the busbars as a sealing element during the manufacturing process, enabling an integrated, seamless seal that further increases the reliability of the electrical connection.

[0016] It is also possible for the first plastic to form a housing for the contacting means, while the second plastic is implemented as a separately molded sealing element. This then results in the busbars, the housing made of the first plastic, and the sealing element made of the second plastic being separate components, which are then assembled to form the contacting means. This can have the advantage that different versions of a contacting means can be manufactured particularly cost-effectively and flexibly thanks to a modular design.

[0017] For the purposes of this application, a busbar, also referred to as a busbar or electrical rail, is a solid electrical conductor for transmitting currents between different components of an electrical system. A busbar can be made of different materials such as copper, aluminum, or other conductive alloys, which can be selected for their ability to conduct high electrical currents as well as their thermal resistance and mechanical stability. A busbar can be designed in various shapes and sizes, such as flat strips, solid blocks, or tubular structures, depending on the specific requirements of the application of the electrical contacting means. According to the invention, the first plastic has a higher hardness than the second plastic. The hardness of plastics can be determined using various standardized methods.These methods are typically designed to measure the plastic material's resistance to penetration or deformation. A common method in this context is the Shore hardness test according to ISO 868 or ASTM D2240. The Shore D and Shore A scales are the most commonly used for determining the hardness of plastics. Shore D is used for harder plastics, while Shore A is used for softer plastics.

[0018] In principle, the electrical contacting device can be intended for the transmission of electrical energy and / or data. Electrical energy can be transmitted in the high-voltage (HV) or low-voltage (LV) range.

[0019] Further advantageous embodiments of the invention are specified in the dependent claims. The features listed individually in the dependent claims can be combined with one another in a technologically expedient manner and can define further embodiments of the invention. Furthermore, the features specified in the claims are further specified and explained in the description, where further preferred embodiments of the invention are presented.

[0020] According to an advantageous embodiment of the invention, the second plastic can be a thermoplastic elastomer. The use of a thermoplastic elastomer (TPE) as the second plastic material offers various technical advantages. TPEs can be processed, for example, using conventional thermoplastic processing techniques such as injection molding, extrusion, and thermoforming, resulting in cost-effectiveness and manufacturing flexibility. Furthermore, TPEs combine the elastomeric properties of rubber with the processing advantages of thermoplastics, allowing them to stretch under load and subsequently return to their original shape. A TPE can, for example, be selected from the group of styrene-based TPEs (SEBS, SBS), polyolefin-based TPEs (TPO, TPV), polyurethane-based TPEs (TPU), polyester-based TPEs (COPE, TPC), and polyamide-based TPEs (PEBA).

[0021] In this context, it is further preferred that the first plastic is not a thermoplastic elastomer.

[0022] According to a further preferred development of the invention, it can also be provided that the second plastic is completely covered by the first plastic. This allows, on the one hand, particularly good mechanical protection of the softer second plastic by the harder first plastic to be achieved. Furthermore, the prestressing of the second plastic, which is desirable for optimizing the sealing properties, can be introduced into the second plastic in a particularly evenly distributed manner by virtue of the complete coverage by the first plastic.

[0023] Furthermore, according to a likewise advantageous embodiment of the invention, it can be provided that the second plastic completely encompasses the busbars along their cross-sectional circumference, which contributes to a further improvement of the sealing properties.

[0024] According to a further particularly preferred embodiment of the invention, it can be provided that the contacting means is designed as a plug or interconnection ring.

[0025] A connector serves to establish a temporary but secure electrical connection without permanent fastening such as soldering. It allows electrical components to be easily connected and disconnected, facilitating installation, maintenance, and repair. A connector can, for example, be designed as a plug connector, in which the plug is inserted directly into a corresponding socket. The plug can also be configured as a screw connector, which is then screwed into a corresponding socket, for example. Another possibility is to design the plug as a bayonet connector. The object of the invention is further achieved by a method for producing an electrical contacting means, in particular for use within a motor vehicle, comprising the following steps:

[0026] - Provision of a plurality of busbars;

[0027] - Providing a first electrically insulating plastic;

[0028] - Providing a second electrically insulating plastic, wherein the first plastic has a higher hardness than the second plastic;

[0029] - arrangement of the second plastic at least in sections between the busbars;

[0030] - at least partially arranging the first plastic on the second plastic in such a way that the second plastic rests on the busbars on the one hand and on the first plastic on the other hand and that handling and / or operation of the contacting means is possible without the risk of electric shock.

[0031] In principle, it would be possible to first form a housing from the first plastic, in which the second plastic and the busbars would then be accommodated.

[0032] It is also possible to form a separate sealing element from the second plastic, which is then mounted between the busbars and the first plastic.

[0033] In a likewise preferred embodiment of the invention, it can also be provided that the busbars are overmolded with the second plastic. Preferably, the busbars are overmolded with the second plastic using an injection molding process. This eliminates the need for separate assembly of the second plastic to the busbars. Furthermore, the injection molding process enables precise and consistent application of the second plastic, resulting in uniform insulation and improved protection of the busbars. This increases electrical safety by minimizing the risk of short circuits or electric shocks.

[0034] It may also be advantageous to further develop the invention in such a way that the busbars and / or the second plastic are overmolded by the first plastic, which can contribute to improved tightness and mechanical stability of the electrical contacting means.

[0035] According to a further preferred embodiment of the subject matter of the invention, it can be provided that the first plastic and the second plastic are injected using a dual-injection molding process to form the electrical contacting means, so that the entire electrical contacting means can be produced in a single injection molding process. The use of the dual-injection molding process to produce the entire electrical contacting means in a single process step offers several technical advantages. One significant advantage lies in process efficiency. Since the entire contacting means is produced in a single pass, cycle times are considerably reduced. This contributes to lowering production costs. Furthermore, potential problems and inaccuracies that can arise from handling between different processing steps are minimized.

[0036] The structural integrity and quality of the final product can also be improved through the use of a dual-injection molding process. The simultaneous injection of different plastic materials achieves excellent bonding between the materials, resulting in a more uniform and durable component. This improved bond minimizes the risk of defects, weak spots, or delamination in the final product, increasing the reliability and service life of the contactor.

[0037] Finally, the invention can also be advantageously implemented such that the first plastic is applied to the second plastic in such a way that the first plastic prestresses the second plastic relative to the busbars. For example, by simultaneously or subsequently overmolding the second plastic with the first plastic, additional pressure can be built up on the first plastic, thereby creating a type of prestressing between the second plastic and the busbars. This prestressing prevents the busbars and the second plastic from separating from one another due to their different thermal expansions, which can occur, for example, due to thermal loads during operation of a motor vehicle. This further improves the tightness of the electrical contacting means, particularly in thermally fluctuating operating environments.

[0038] The invention will be explained in more detail below with reference to figures without limiting the general inventive concept.

[0039] It shows:

[0040] Figure 1 shows various manufacturing states of an electrical contacting means, each in a perspective view,

[0041] Figure 2 shows a busbar in a schematic cross-sectional view,

[0042] Figure 3 shows a motor vehicle with electrical contacting means in a schematic block diagram.

[0043] The illustrations ac of Figure 1 show, in summary, an electrical contacting means 1, in particular for use within a motor vehicle 2, as is also shown by way of example in Figure 3. In the embodiment shown, the contacting means 1 is designed as a plug 7.

[0044] The electrical contacting means 1 comprises a plurality of busbars 3, which are encompassed by a first electrically insulating plastic 4 such that handling and / or operation of the contacting means 1 is possible without the risk of electric shock, as shown, for example, in Figure 1 c. The first plastic 4 thus forms a housing for the electrical contacting means 1.

[0045] In the illustrated embodiment, a total of four busbars 3 with a rectangular conductor cross-section are provided, running essentially parallel to one another. A second electrically insulating plastic 5 is arranged between the busbars 3 and the first plastic 4, which second plastic 5 rests on the busbars 3 on the one hand and on the first plastic 4 on the other. The first plastic 4 has a higher hardness than the second plastic 5. In the embodiment shown in Figure 1, the second plastic 5 is a thermoplastic elastomer. The second plastic 5 thus forms a sealing element that seals the busbars 3 against the first plastic 4.

[0046] Some of the busbars 3 have fixing / connection sections 8 protruding from the busbars 3, which allow improved fastening of the second plastic 5 to the busbars 3, in particular optimized fixing against offset in the longitudinal direction of the busbars 3. Accordingly, the fixing / connection sections 8 protrude from the busbars 3 essentially perpendicular to the longitudinal direction of the busbars 3. The fixing / connection sections 8 can then rest against the second plastic 5 and / or extend through it.

[0047] As can be clearly seen from Figure 1 (c), the second plastic 5 is completely covered by the first plastic 4. The second plastic 5 completely encompasses the busbars 3 along their cross-sectional circumference 6, which can be clearly seen from the illustration in Figure 2.

[0048] Possible methods for producing the electrical contacting means 1 are explained in more detail below. This basically comprises the following steps: First, a plurality of busbars 3, a first electrically insulating plastic 4, and a second electrically insulating plastic 5 are provided, the first plastic 4 having a higher hardness than the second plastic 5.

[0049] Subsequently, the second plastic 5 is arranged at least in sections between the busbars 3, which can also be seen in Figure 1 (b). After this, the first plastic 4 is arranged at least in sections on the second plastic 5 in such a way that the second plastic 5 rests on the busbars 3 on the one hand and on the first plastic 4 on the other, and that handling and / or operation of the contacting means 1 is possible without the risk of electric shock. This manufacturing state is shown in Figure 1 (c).

[0050] In the exemplary embodiment shown in Figure b of Figure 1, the busbars 3 are overmolded by the second plastic 5. As can be seen in Figure c of Figure 3, the second plastic 5 is also completely overmolded by the first plastic 4. The first plastic 4 and the second plastic 5 can be injected using a bi-injection molding process to form the electrical contacting means 1.

[0051] The first plastic 4 is applied to the second plastic 5 in such a way that the first plastic 4 causes a prestress of the second plastic 5 with respect to the busbars 3.

[0052] It is also possible for the busbars 3 to be initially molded all the way around in a first injection molding process with a second plastic 5 designed as a thermoplastic elastomer. This molded-on second plastic 5 can, in addition to sealing and insulating, also perform additional functions such as, for example, positioning the busbars 3 relative to one another. In a second injection molding process, the complete geometry of the second plastic 5 is then molded with a rigid first plastic. Figure 3 shows a possible application of the contacting means 1 in a motor vehicle 2. Here, a first contacting means 1 designed as a plug 7 is used to electrically contact a controller 10 with an electrical machine 9, and a second contacting means 1 designed as a plug 7 is used to electrically contact an electrical energy source 11 with an electrical machine 9.

[0053] The invention is not limited to the embodiments illustrated in the figures. The above description is therefore not to be considered restrictive, but rather explanatory. The following claims are to be understood in such a way that a stated feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. Where the claims and the above description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing a priority.

[0054] List of reference symbols

[0055] 1 contact agent

[0056] 2 Motor vehicle 3 Busbars

[0057] 4 first plastic

[0058] 5 second plastic

[0059] 6 Cross-sectional circumference

[0060] 7 Plug 8 Fixing / connection sections

[0061] 9 electric machine

[0062] 10 Control

[0063] 11 Energy source

Claims

Claims 1 . Electrical contacting means (1), in particular for use inside a motor vehicle (2), comprising a plurality of busbars (3), which are encompassed at least in sections by a first electrically insulating plastic (4) in such a way that handling and / or operation of the contacting means (1) is possible without the risk of an electric shock, characterized in that a second electrically insulating plastic (5) is arranged at least in sections between the busbars (3) and the first plastic (4), which second electrically insulating plastic (5) rests on the one hand on the busbars (3) and on the other hand on the first plastic (4), wherein the first plastic (4) has a higher hardness than the second plastic (5).

2. Contacting means (1) according to claim 1, characterized in that the second plastic (5) is a thermoplastic elastomer.

3. Contacting means (1) according to claim 1 or 2, characterized in that the second plastic (5) is completely covered by the first plastic (4).

4. Contacting means (1) according to one of the preceding claims, characterized in that the second plastic (5) completely encompasses the busbars (3) along their cross-sectional circumference (6).

5. Contacting means (1) according to one of the preceding claims, characterized in that the contacting means (1) is designed as a plug (7) or interconnection ring.

6. A method for producing an electrical contacting means (1), in particular for use within a motor vehicle (2), comprising the following steps: - providing a plurality of busbars (3); - providing a first electrically insulating plastic (4); - providing a second electrically insulating plastic (5), wherein the first plastic (4) has a higher hardness than the second plastic (5); - at least partially arranging the second plastic (5) between the busbars (3); - at least partially arranging the first plastic (4) on the second plastic (5) in such a way that the second plastic (5) rests on the busbars (3) on the one hand and on the first plastic (4) on the other hand and that handling and / or operation of the contacting means (1) is possible without the risk of electric shock.

7. Method according to claim 6, characterized in that the busbars (3) are overmolded by the second plastic (5).

8. Method according to claim 6 or 7, characterized in that the busbars (3) and / or the second plastic (5) are overmolded by the first plastic (4).

9. Method according to one of claims 6-8, characterized in that The first plastic (4) and the second plastic (5) are injected in a bi-injection molding process to form the electrical contacting means (1).

10. The method according to any one of claims 6-9, characterized in that the first plastic (4) is applied to the second plastic (5) in such a way that the first plastic (4) prestresses the second plastic (5) relative to the busbars (3).

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