Method for manufacturing an electrical wiring harness and electrical wiring harness

Abstract

A method for manufacturing an electrical wiring harness (2) is described, wherein an assembly device (4) is provided which has a retaining plate (6) and one or more guide pins (8) which are arranged on the retaining plate (6), wherein one or more conductors (10) are mounted according to a laying pattern and for this purpose at least a part of the conductors (10) is guided around the guide pins (8), wherein a forming tool (12) is provided, wherein the forming tool (12) and the retaining plate (6) are moved towards each other, wherein the conductors (10) are encased with a potting compound (16) which is directed onto or into the forming tool (12) and is then hardened, so that the potting compound (16) and the conductors (10) form a composite in which the conductors (10) are fixed according to the laying pattern, wherein the composite is removed from the retaining plate (6) and pulled off the guide pins (8).Furthermore, a corresponding electrical wiring harness (2), a mounting device (4) and a forming tool (12) are described.

Description

[0001] The invention relates to a method for producing an electrical wiring harness, also known as a conductor harness, and to such an electrical wiring harness, in particular for a motor vehicle.

[0002] A wiring harness is designed to connect multiple components and typically includes multiple conductors, often with a branched conductor structure. Automated production is often the preferred method for manufacturing such wiring harnesses.

[0003] In applications where a specific routing pattern for the individual conductors is required, considerable effort is often required. Especially in automotive applications, especially with large-area, branched routing patterns, such as those used in doors or as cell contact systems in batteries, manufacturing with conventional simple cables is complex. Due to the size of such cable harnesses, the use of printed circuit boards (PCBs) is often not practical from a technical and economic perspective.

[0004] DE 10 2012 205 020 A1 and WO 2020 / 161047 A1 each disclose cell contacting systems for batteries in which pin-shaped guide elements are arranged on a base plate, along which the conductors are laid according to a predetermined laying pattern.

[0005] Against this background, the invention is based on the object of providing a cost-effective and simple method of manufacturing a wiring harness specifically for a motor vehicle. Furthermore, a corresponding wiring harness is to be provided.

[0006] The object is achieved according to the invention by a method for producing an electrical cable harness, wherein an assembly device is provided which has a holding plate and one or more guide pins which are arranged on the holding plate, wherein one or more conductors are mounted according to a laying pattern and for this purpose at least some of the conductors are guided around the guide pins, wherein a molding tool is provided which is brought up to the holding plate and to the conductors, wherein the conductors are cast with a casting compound which is guided onto or into the molding tool and is then cured, so that the casting compound and the conductors form a composite in which the conductors are fixed according to the laying pattern, wherein the composite is removed from the holding plate and pulled off the guide pins.

[0007] The problem is further solved by an electrical wiring harness manufactured according to such a method. The electrical wiring harness is also referred to simply as "wiring harness" below. The wiring harness is used, for example, in a motor vehicle, for example, in a door module or cell contact system. The wiring harness is, in particular, a flat cable harness.

[0008] Advantageous embodiments, further developments, and variants are the subject of the dependent claims. The statements regarding the method also apply mutatis mutandis to the electrical wiring harness, and vice versa. If steps of the method are described implicitly or explicitly below, advantageous embodiments for the electrical wiring harness result from the fact that it is manufactured according to a method that includes one or more of these steps.

[0009] A key concept of the present invention is, in particular, a two-stage process in which the conductors are positioned using guide pins in a first stage and then potted with the potting compound in a second stage, so that the potting compound forms a composite with the conductors, which then becomes the actual cable harness. The process is therefore an additive process overall, or more precisely a casting process. In the process, a casing or bed for the conductors is formed from the potting compound. This casing or bed is initially formed from the potting compound. The potting compound is initially liquid and / or flowable and becomes solid upon curing.

[0010] The process is used to manufacture an electrical wiring harness. Such a harness is used, for example, in the electrical system of a motor vehicle. Typical dimensions for the wiring harness are a width and a length of 100 mm or several 100 mm, e.g., 300 mm x 200 mm, and a thickness (also: height) in the range of 1 mm to 10 mm, e.g., 2.5 mm. Depending on the application, other dimensions may also result. In principle, however, the wiring harness can be manufactured and used for any application requiring an electrical connection, which is then realized by the wiring harness.

[0011] In a first step of the method, an assembly device is provided. This device has a holding plate (also: mounting plate) and one or more guide pins (also: winding pins, deflection pins, assembly pins) which are arranged on the holding plate. The guide pins each extend away from the holding plate in a longitudinal direction and in particular perpendicular to the holding plate. The guide pins are in particular parallel to one another. The holding plate is preferably flat so that in combination with the guide pins it forms a pin board. The guide pins are preferably firmly attached to the holding plate, e.g. manufactured monolithically with it or inserted into it. Alternatively, the guide pins are movable relative to the holding plate, e.g. spring-mounted in the longitudinal direction.

[0012] In a second step (assembly), one or more conductors are mounted according to a predetermined routing pattern. For this purpose, at least some of the conductors are guided around the guide pins (i.e., the conductors are "routed"). In other words, the conductors are arranged along the guide pins.

[0013] In a third step, a forming tool is provided in addition to the assembly device, and the forming tool and the holding plate are moved toward each other. For example, the forming tool is moved toward the holding plate and the ladder, or vice versa. Depending on the design of the forming tool and the specific implementation of the method, the forming tool is moved entirely or partially toward the holding plate and the ladder before or after assembly. In other words, the third step is performed before or after the second step (assembly) or comprises several sub-steps, at least one of which is performed before the second step and at least one after the second step.

[0014] Finally, the conductors are arranged on or in the forming tool. The conductors are held primarily or even exclusively by the guide pins and thus, in particular, spaced from a surface of the forming tool at a certain distance, i.e., held in mid-air, so to speak. The distance is typically in the range of 0.5 to 5 times the diameter of an individual conductor.

[0015] In a particularly preferred embodiment, the forming tool has a through-opening for each of the guide pins. When the forming tool is brought closer to the retaining plate, the guide pins are each guided through one of the through-openings, i.e., the forming tool is essentially plugged onto the pin board, particularly prior to the conductors being mounted. The forming tool is either single-part or multi-part, preferably two-part. In a multi-part embodiment, a first part is plugged onto the guide pins prior to assembly, and a second part is then brought closer to the retaining plate, the guide pins, and the conductors guided around them only after assembly.

[0016] Preferably, several, in particular a large number (e.g. 10 to 100) of guide pins and / or conductors are present in order to realize a correspondingly complex laying pattern. In a suitable embodiment, the conductors are each designed as wire, enameled wire, bare wire or the like. Cables and lines can also be used as conductors in principle, but the conductors preferably have no sheath or only a thin sheath (i.e. thinner than 1 / 10 the diameter of the conductor). The conductors are in particular each arranged flat and also generally essentially in a common plane, wherein "essentially" is understood to mean that individual conductors may cross one another depending on the laying pattern and then lie above or below one another.

[0017] In a fourth step (potting), the conductors are potted with a potting compound, in particular cast around or embedded in the potting compound. For this purpose, the potting compound is directed onto or into the mold, in particular poured or injected, and then the potting compound is cured so that the potting compound and the conductors form a composite, namely an electrical wiring harness. This is essentially a 2D structure. In the composite, the conductors are fixed according to the laying pattern, i.e. the cured potting compound fixes the conductors according to the laying pattern. The conductors are preferably fully embedded in the potting compound. Alternatively, the conductors only partially protrude from the potting compound.

[0018] Preferably, the casting compound is introduced into or onto the mold in stages, i.e., in several successive steps. In other words, the casting compound is not poured all at once, but gradually. This improves the quality of the bond and prevents holes or cavities.

[0019] In a preferred embodiment, the molding tool has a first tool plate (generally a first part) and a second tool plate (generally a second part), between which the conductors are then cast with the casting compound. The first tool plate has the through-openings for the guide pins and is placed on the holding plate before the conductors are mounted. After the conductors have been mounted and before they are cast with the casting compound, the first tool plate and the second tool plate are placed on top of one another, i.e. brought together. The entire molding tool is now assembled and placed on the holding plate. The first and second tool plates now enclose a hollow space, also referred to as the mold space or mold chamber. The conductors are arranged in the hollow space. The casting compound is also poured into the hollow space. This fills the hollow space, preferably completely.For pouring the casting compound, the mold has a corresponding filling opening (also known as a sprue). The filling opening is advantageously located on the same side of the mold as the openings for the guide pins. A particularly advantageous design is one in which the filling opening is located in the first mold plate.

[0020] Without limiting generality, the following assumes a mold with a first and / or a second mold plate. However, the explanations also generally apply to a mold with a first and a second part instead of the first and second mold plates.

[0021] The two aforementioned tool plates are each in particular plate-shaped and extend parallel to one another. To form the cavity, one or both tool plates have a corresponding recess which is bordered by a step, a collar or the like. Accordingly, the tool plates are designed either as a pair of half-shells or as a combination of a half-shell and a cover. To prevent potting compound from escaping laterally during potting, the molding tool suitably has a circumferential seal, e.g. made of silicone. The seal runs around the recess and thus also the conductors and runs, for example, along the step or the collar and, for example, in a corresponding groove. Depending on the design of the molding tool and the fill level of the potting compound after potting, a seal may not be necessary under certain circumstances.

[0022] In principle, as an alternative to the design with two mold plates and one cavity, it is also possible to use only a single mold plate as the molding tool, onto which the casting compound is poured and then optionally smoothed. Accordingly, in a suitable design, the molding tool has only the first mold plate or only the second mold plate, as described.

[0023] The conductors are expediently rigid and in any case monolithic, i.e. not as stranded conductors or the like, in order to be as inflexible as possible and to slip as little as possible during potting. Each conductor is expediently fixed at the end, in particular with a clamping fork into which one end of the conductor is clamped. The clamping fork is suitably integrated into a plug which forms part of the cable harness. Preferably, several conductors are fastened to the plug. The plug is, for example, an insulation displacement plug, also referred to as IDC, or similar. In a preferred embodiment, the molding tool and / or the holding plate has at least one recess into which a corresponding plug is inserted, preferably in a form-fitting manner. At least one of the conductors is fastened to this plug before or after.Inserting the connector into the recess prevents it from becoming completely encapsulated during potting. The connector is inserted and the conductor is fastened to it during assembly, and thus before potting. The recess is either a blind hole or, like the through-openings, a through-hole. The recess is expediently arranged on the same side of the molding tool as the through-openings for the guide pins. A particularly expedient embodiment is one in which the recess is arranged in the first tool plate. The connectors each have a plug-in direction which is oriented such that it is parallel to the longitudinal direction in the finished state of the cable harness.

[0024] The molding tool as a whole or one or both tool plates are suitably made of metal, e.g., steel or aluminum. Alternatively, the molding tool as a whole or one or both tool plates are made of a plastic, preferably PE, PP, or PA. In an advantageous embodiment, the molding tool as a whole or one or both tool plates are formed as a deep-drawn part.

[0025] During casting, air escapes from the cavity, preferably past the guide pins, through the through-holes and / or, if necessary, through one or more recesses for a respective connector. Additional venting openings in the mold, particularly in the first mold plate, are also suitable.

[0026] In a fifth step (demolding), the composite is removed from the holding plate and pulled off the guide pins. In other words, the guide pins only hold the composite temporarily and therefore do not remain on the cable harness in the finished state. The mold, on the other hand, can either be completely separated from the composite or remain wholly or partially on the composite as a sacrificial part, or be destroyed during casting. Accordingly, in a suitable design, the composite is removed not only from the holding plate and the guide pins, but also from the mold during demolding. The mold is then used repeatedly to produce several similar cable harnesses. Alternatively, the mold remains wholly or partially connected to the composite when removed from the holding plate and is then designed wholly or partially as a sacrificial part.A mold or tool plate made of plastic, which is designed as a deep-drawn component, for example, is particularly suitable for this purpose.

[0027] Optionally, a release agent is applied to the mold before casting to simplify demolding.

[0028] The guide pins each advantageously have a tapered, in particular conical or truncated cone-shaped tip. The tip is the end of the guide pin furthest from the holding plate. The tapered tip facilitates demolding. The tip is expediently at least as long as the composite is thick. Away from the tip, however, the respective guide pin suitably has a constant width, in particular diameter. Each guide pin thus has a straight section and a tapered section (the tip), which adjoin one another. During assembly, the conductors are preferably guided around the straight, e.g. cylindrical, section so that slipping in the longitudinal direction is prevented. After assembly and before potting, the guide pins are then moved back so that the conductors are pushed onto the tapered sections. The conductors are then potted.During the subsequent demoulding, the guide pins are then completely retracted and the composite is removed.

[0029] In a particularly advantageous embodiment, the method uses a flip technique, i.e. the assembly device and the first tool plate (generally the molding tool or a part thereof) are turned over after the conductors have been mounted and before potting, so that the through-openings are now above the conductors. For assembly, the assembly device is oriented in a first direction, so that the guide pins extend upwards from the holding plate and the conductors and, if applicable, the first tool plate can be mounted particularly easily from above, with the holding plate underneath. An inclined orientation is also conceivable, depending on the preference of the fitter carrying out the assembly. After assembly, the assembly device with the mounted conductors is then turned over, in particular upside down, so that the conductors are now no longer above, but below the holding plate.The assembly device with the conductors and, if applicable, also with the first tool plate is moved towards the second tool plate, for example lowered. In a similar way, the second tool plate can also be moved upwards. In this case, the guide pins in particular abut against the second tool plate. The second tool plate preferably has no holes whatsoever and thus serves as a collecting surface or tray for the potting compound, which can, however, spread upwards, i.e. along the guide pins in the longitudinal direction and generally towards the holding plate. The potting compound either spreads freely upwards or is limited by the first tool plate. In the latter case, the potting compound enters the passage openings when it reaches the first tool plate, which is expediently avoided.Therefore, during the casting process, casting compound is preferably only introduced into the mold until it reaches the openings. In other words, the fill level of the casting compound in the mold is monitored, and when a certain limit is reached, the casting compound is stopped.

[0030] As already described, the guide pins each extend in a longitudinal direction. Measured in this longitudinal direction, the cavity has a height, especially when the mold is closed, in which the casting is carried out. In a preferred embodiment, the guide pins protrude further from the first tool plate than the cavity is tall, measured in the longitudinal direction. Thus, measured from the holding plate, the guide pins have a height that is greater than the sum of the height of the cavity and the height of the first tool plate (each measured in the longitudinal direction). In short, the guide pins have an excess length, which simplifies the assembly of the conductors.

[0031] The excessive length of the guide pins can be problematic in that a multi-part mold can then no longer be fully closed for potting. There are several approaches to solving this. In principle, it is conceivable for the second tool plate to have corresponding through-openings for the guide pins, similar to the first tool plate, which are then expediently sealed against the escape of potting compound. However, since this is complex, a hole-free second tool plate is preferred. In order to still be able to close the mold optimally or - with only a second tool plate without an additional first tool plate - at least to be able to bring the conductors sufficiently close to the second tool plate, the guide pins are suitably designed in such a way that they give way when they hit the second tool plate. Two suitable designs are described below.

[0032] In a first suitable embodiment, the guide pins are each compressible in the longitudinal direction and are compressed before or while the first tool plate and the second tool plate are placed on top of one another. In other words: the two tool plates are moved towards one another after assembly and before casting, and at the latest as soon as the guide pins abut the second tool plate, the guide pins are automatically compressed in the longitudinal direction, so that the second tool plate can be moved up to the first tool plate and the cavity is closed. The guide pins then extend, in principle, over the entire height of the cavity. The holding plate itself is not moved relative to the first tool plate, and the guide pins themselves are not moved, but merely compressed. The guide pins are compressible, for example, by being retractable, e.g.by a telescopic mechanism, or compressible, e.g. spring-mounted by a spring mechanism. The guide pins are in particular reversibly compressible, so that they extend back to their original length, e.g. when the second tool plate is removed or during demolding or when the composite is pulled off. In a suitable embodiment, the guide pins are spring-mounted within blind holes (e.g. blind bores) in the holding plate, i.e. they can be moved into the holding plate relative to the latter. This is particularly advantageous when the mold has only a single tool plate, onto which the holding plate is then placed directly.

[0033] In a second suitable embodiment, the holding plate is moved longitudinally away from the first tool plate before or while the first tool plate and the second tool plate are placed on top of one another. Thus, instead of compressing the guide pins as in the first embodiment, these are displaced, in particular retracted, in the longitudinal direction together with the holding plate. Relatively speaking, the first tool plate is thus displaced from the holding plate along the guide pins toward the second tool plate. The guide pins are, in particular, attached to the holding plate.

[0034] In both designs, the conductors on the guide pins are also moved longitudinally and in the direction of the tips of the guide pins if necessary.

[0035] Potting is preferably carried out as pressure-free as possible and suitably solely or predominantly by gravity. For this purpose, the potting compound is poured into or onto the molding tool, in particular from above. This minimizes any displacement of the conductors by the potting compound. In a suitable embodiment, the potting compound is poured into the molding tool at an injection pressure in the range of 0 bar to 10 bar (in particular in an RTM process, RTM = “Resin Transfer Molding”), i.e. pressure-free at 0 bar or in a range of more than 0 bar to 10 bar. However, the necessary and / or permissible injection pressure is generally determined by the flow behavior of the respective potting compound and / or by the stability of the molding tool and is expediently selected accordingly.

[0036] The potting compound is preferably a cast polyamide, hot melt, epoxy resin, silicone, PA6 or polyurethane. A cast polyamide is mixed together in a mixing machine from several individual material components before potting, i.e. outside the mold. With a polyurethane, on the other hand, two components (base and blowing agent) of the polyurethane are usually mixed during potting, particularly inside the cavity, so that a polyurethane foam is then created directly in or on the mold. A hot melt adhesive is a melt adhesive or hot melt adhesive that is typically solid at room temperature and, when heated, is in a hot state as a viscous liquid, which is then poured into or onto the mold. A hot melt adhesive is particularly cast hot (e.g. approx. 180 °C) using a low-pressure injection molding process.Silicone is also suitable for potting at low injection pressure, advantageously without heat input or release agents. The injection pressure depends particularly on the underlying conditions, such as the type of material used for the potting compound. For example, hotmelt low-pressure potting operates at approximately 5 bar to 50 bar. Silicone also cures advantageously in a cold reaction; alternatively, it can be cured using UV radiation. However, ideally, no UV radiation, microwave radiation, heat, etc., is required or used during curing.

[0037] The potting compound is suitably designed in such a way that during casting and / or curing of the potting compound, a plastic is formed virtually on site in the mold, in particular by polymerization of an introduced monomer, and accordingly the potting compound is then produced by an in-situ polymerization process. The cast polyamide mentioned above is particularly suitable for this purpose. “In-situ polymerization” is understood in particular to mean that the potting compound is introduced into the mold in the form of one or more starting components and only there does polymerization take place to form the actual plastic. The then particularly polymerized plastic is preferably a thermoplastic, specifically, for example, polyamide.For example, in the in situ polymerization of polyamide, a mixture of a monomeric lactam and a catalyst is combined with a mixture of a monomeric lactam and an activator to initiate the polymerization to form the polyamide. The respective monomeric lactam, the catalyst, and the activator then form the potting compound.

[0038] An in-situ polymerization process is advantageous in this case primarily because the casting compound used in casting, e.g., injection molding, has a significantly lower viscosity than a thermoplastic melt, which allows, for example, lower pressures to be applied. Depending on the composition and, accordingly, the plastic of which the cured casting compound is ultimately made and its desired properties, the casting compound has a viscosity comparable to water. In particular, the casting compound also has a lower viscosity than the epoxy resin or polyurethane systems commonly used today.

[0039] Accordingly, in some cases, the mold can be filled entirely without overpressure by utilizing the dead weight of the casting compound, making it typically suitable for all known casting processes, particularly gravity casting, injection molding, rotational casting, and centrifugal casting. Alternatively, the low viscosity allows for high injection speeds, although in this case, overpressure is required. Furthermore, the low viscosity of the casting compound allows for greater freedom in mold design, as the casting compound flows into even the smallest gaps and fills the smallest material recesses.

[0040] Furthermore, the potting compound expediently has a favorable wetting behavior, which is particularly advantageous if, in addition to the conductors, one or more inserts are provided and used, which are inserted into the mold before the potting compound is introduced, so that these inserts are then enveloped or coated by the potting compound.

[0041] Especially when using corresponding inserts, it is advantageous that corresponding in-situ polymerization processes operate at lower temperatures than is the case with a thermoplastic melt, since in this case, even relatively sensitive inserts can be coated or encapsulated with a suitable plastic. Overall, the mechanical and thermal stress on the conductors and, if applicable, inserts is therefore significantly lower compared to conventional injection molding of thermoplastic melts or hot melts.

[0042] Suitable casting compounds are those that form a thermoplastic. Polyamide is preferred, and the cured casting compound is then a cast polyamide element. In this case, the casting compound typically contains lactam, a catalyst, and an activator. Caprolactam from renewable raw materials, for example, is also used as the lactam.

[0043] A thermoplastic produced in this way exhibits all the typical properties that make it attractive for use in the automotive sector, particularly advantageous mechanical behavior and high thermal and / or chemical resistance. Furthermore, thermoplastics are generally suitable for plastic welding and are relatively easy to recycle. In-situ polymerization also offers the advantage that the composite can be easily removed from the mold without the use of a release agent, as is typically necessary in foaming processes.

[0044] In a suitable design, the potting compound has the lowest possible viscosity during casting. In general, the casting materials preferred here as potting compounds often flow more easily than injection-molding materials because they have a lower viscosity. The thermal stress on any inserts is also often lower than with injection molding.

[0045] Advantageously, the casting compound undergoes no or only the smallest possible change in volume during curing, e.g. less than 5%.

[0046] A design in which a heating and / or cooling device is integrated into the molding tool is also expedient, for heating and / or cooling the casting compound, particularly during casting, curing, and / or demolding. The heating and / or cooling device tempers the casting compound and thereby, in particular, controls its curing time. This advantageously optimizes the distribution of the casting compound on or within the molding tool.

[0047] In summary, the following advantages arise: a particularly low injection pressure can be used during potting, which prevents the conductors from shifting. With an appropriately selected potting compound, no foaming pressure is created in the mold. The mold does not require a high closing or clamping force. Furthermore, conductor sets of almost unlimited sizes can be realized, especially with an appropriately selected potting compound. Free potting in a housing, which remains on the conductor set after demolding, is also possible. Additional connectors can be flexibly integrated into the cable set.

[0048] The object is also achieved, in particular, by an assembly device and a molding tool as described above. The statements regarding the method and the wiring harness also apply analogously to the assembly device and the molding tool. Advantageous embodiments for these result, in particular, from the fact that they are designed to carry out the method.

[0049] In the following, exemplary embodiments of the invention are explained in more detail with reference to a drawing. In each case, the following schematically show: Fig. 1 to 5 steps of a method for producing an electrical wiring harness, Fig. 6 an electrical wiring harness, Fig. 7 another representation of the procedure, Fig. 8 an assembly device, a first tool part and several conductors, Fig. 9 the tool part Fig. 8 viewed from below, Fig. 10 an electrical wiring harness, Fig. 11 a guide pin with a tapered tip in two different positions, Fig. 12 an electrical wiring harness in a perspective view, Fig. 13 the electrical wiring harness Fig. 12 in a top view.

[0050] In the Fig. 1 to 5 illustrate steps of a method for producing an electrical wiring harness 2. A wiring harness 2 produced by this method is shown in a cross-sectional view in Fig. 6. The individual steps of the procedure are also shown in Fig. 7 is shown as a flow chart.

[0051] In a first step S1 ( Fig. 1) of the method, an assembly device 4 is provided. This device has a holding plate 6 and one or more guide pins 8, which are arranged on the holding plate 6. The guide pins 8 each extend in a longitudinal direction L and perpendicular to the holding plate 6. The guide pins 8 are parallel to one another. The holding plate 6 is flat, so that in combination with the guide pins 8 it forms a pin board. The guide pins 8 are fixedly attached to the holding plate 6 in the present case. Alternatively, the guide pins 8 are movable relative to the holding plate 6. In a second step S2 (assembly, also Fig. 1) one or more conductors 10 are mounted according to a particular predetermined laying pattern and for this purpose at least a part of the conductors 10 is guided around the guide pins 8:

[0052] In a third step S3, in addition to the assembly device 4, a forming tool 12 is provided and this and the holding plate 6 are moved towards each other ( Fig. 2). For example, the forming tool 12 is brought up to the holding plate 6 and to the conductors 10 or vice versa. Depending on the design of the forming tool 12 and the specific implementation of the method, the forming tool 12 is brought up to the holding plate 6 and to the conductors 14 entirely or partially before or after assembly. In the design shown here, the third step S3 comprises several sub-steps, one of which is carried out before the second step S2 and one after the second step S2. Ultimately, the conductors 10 are then arranged on or in the forming tool 12. The conductors 10 are held primarily or even exclusively by the guide pins 8 and are thus spaced from a surface of the forming tool 12.

[0053] In the embodiment shown here, the forming tool 12 has a through-opening 14 for each of the guide pins 8. When the forming tool 12 is brought to the holding plate 6, the guide pins 8 are each guided through one of the through-openings 14 before the conductors 10 are mounted. The forming tool 12 is in the Fig. 1 to 5 in two parts and a first part is placed on the guide pins 8 before assembly ( Fig. 1) and a second part is then only brought to the holding plate 6, the guide pins 8 and the conductors 10 guided around it after assembly ( Fig. 2).

[0054] In this case, several guide pins 8 and conductors 10 are provided to realize a correspondingly complex laying pattern. For clarification, Fig. 8 shows a perspective view of a detailed embodiment of a mounting device 2, a forming tool 12 (only partially shown) and a laying pattern for several conductors 10. In Fig. 9 is the arrangement of Fig. 8 shown from below. The guide pins 8 are in Fig. 8 is not shown, only the through-openings 14 are visible. As can be seen from Fig. As can be seen in Figure 8, the conductors 10 are arranged flat and generally essentially in a common plane. Fig. 10 shows a top view of a cable set 2, which is provided with the arrangement of the Fig. 8 and Fig. 9, with the embedded conductors 10 explicitly shown visible.

[0055] In a fourth step S4 (pouring, Fig. 4) The conductors 10 are potted with a potting compound 16, which is applied to or into the mold 12, e.g., poured or injected, and then cured, so that the potting compound 16 and the conductors 10 form a composite, namely an electrical wiring harness 2. This is essentially a 2D structure. In the composite, the conductors 10 are fixed according to the laying pattern.

[0056] In the embodiment shown here, the molding tool 12 has a first tool plate 18 (generally a first part) and a second tool plate 20 (generally a second part), between which the conductors 10 are then potted with the potting compound 16 ( Fig. 4). The first tool plate 18 has the through-openings 14 for the guide pins 8 and is placed on the holding plate 6 ( Fig. 1) before the conductors 10 are mounted. After the conductors 10 have been mounted and before they are cast with the casting compound 16, the first tool plate 18 and the second tool plate 20 are placed on top of each other ( Fig. 2). The entire mold 12 is now assembled and placed on the holding plate 6. The first and second mold plates 18, 20 now enclose a cavity 22 in which the conductors 10 are arranged and into which the potting compound 16 is poured. For pouring the potting compound 16, the mold 12 has a corresponding filling opening 24. In this case, this is arranged on the same side of the mold 12 as the through-openings 14, i.e., here in the first mold plate 18.

[0057] The two tool plates 18, 20 are each plate-shaped and extend parallel to one another. To form the cavity 22, the second tool plate 20 has a corresponding recess, which is bordered by a step 26, a collar, or the like. Accordingly, the tool plates 18, 20 are designed here as a combination of a half-shell (second tool plate 20) and a cover (first tool shell 18). To prevent lateral leakage of potting compound 16 during potting, the mold 12 has a circumferential seal 28, which here surrounds the recess and thus also the conductor 10 and runs along the step 26 in a corresponding groove (not shown).

[0058] In principle, as an alternative to the design with two tool plates 18, 20 and a cavity 22, it is also possible to use only a single tool plate 18, 20 as the molding tool 12, onto which the potting compound 16 is poured and then optionally smoothed. Accordingly, in an alternative design not shown, the molding tool 12 has only the first tool plate 18 or only the second tool plate 20 as described. Both can be designed with a recess or flat without a recess.

[0059] In the present case, each conductor 10 is fixed at its end, namely with a clamping fork, into which one end of the conductor 10 is clamped. The clamping fork is integrated into a plug 30, which is part of the cable set 2 and in Fig. 10 is shown. In the present case, several conductors 10 are fastened to a respective plug 30. The molding tool 12 has a recess 32 for each plug 30, into which the plug 30 is inserted. At least one of the conductors 10 is fastened to this plug 30 before or after. Inserting it into the recess 32 also prevents the plug 30 from being completely encapsulated during potting. The insertion of the plug 30 and the fastening of the conductor 10 thereto takes place during assembly (second step S2) and thus before potting (fourth step S4). The recess 32 is arranged on the same side of the molding tool 12 on which the through-openings 14 are arranged, i.e. in the present case in the first tool plate 18.

[0060] In a fifth step S5 (demolding), the composite is removed from the holding plate 6 and pulled off the guide pins 8. The molding tool 12, however, can either be completely separated from the composite (as shown here) or remain completely or partially attached to the composite as a sacrificial part (not shown) or be destroyed during casting (also not shown).

[0061] An embodiment of the guide pins 8 is shown in Fig. 11. The guide pin 8 shown there has a tapered, here truncated cone-shaped tip 34. The tip 34 is the end of the guide pin 8 remote from the holding plate 6. In Fig. 11, the tip 34 is at least as long as the composite is thick. However, apart from the tip 34, the guide pin 8 has a constant width. The guide pin 8 thus has a straight section 36 and a tapered section (the tip 34), which adjoin one another. During assembly, the conductors 10 are guided around the straight section 36 so that slipping in the longitudinal direction L is prevented. After assembly and before potting, the guide pins 8 are then moved back so that the conductors 10 are each pushed onto the tapered sections 34. The conductors 10 are then potted, the result is shown in Fig. 11 shown on the left. During the subsequent demoulding, the guide pins 8 are then completely retracted and thus the composite is removed, in Fig. 11 shown on the right.

[0062] In the design according to the Fig. 1 to 5, the method uses a flip technique, ie the mounting device 2 and the first tool plate 18 are turned over after mounting the conductors 10 and before casting (cf. Fig. 1 and Fig. 2), so that the through-openings 14 are now located above the ladder 10. For assembly, the mounting device 2 is oriented in a first direction ( Fig. 1), so that the guide pins 8 extend upwards from the holding plate 6 and the ladder 10 and the first tool plate 18 are to be mounted from above, the holding plate 6 is located underneath. After assembly, the

[0063] Mounting device 2 with the mounted ladders 10 is turned over in such a way that the ladders 10 are no longer above, but below the holding plate 6 ( Fig. 2). The assembly device 2 with the conductors 10 and the first tool plate 18 is brought to the second tool plate 20 ( Fig. 2). Equivalently, the second tool plate 20 can also be moved upwards. In doing so, the guide pins 8 abut against the second tool plate 20. The second tool plate 20 has no holes in the present case and thus serves as a collecting surface or tray for the potting compound 16, which can, however, spread upwards, i.e., along the guide pins 8 in the longitudinal direction L and generally towards the holding plate 6. The potting compound 16 either spreads freely upwards (not shown) or is limited by the first tool plate 20 ( Fig. 4). In the latter case, the casting compound 16 potentially enters the through-openings 14 upon reaching the first tool plate 18. Therefore, during casting, the casting compound 16 is fed into the mold 12 only until the casting compound 16 reaches the through-openings 14, as shown in Fig. 4 shown.

[0064] Measured in the longitudinal direction L, the cavity 22 has a height of 38. In the embodiment shown here, the guide pins 8 protrude further from the first tool plate 18 than the cavity 22 is high, measured in the longitudinal direction L. Thus, the guide pins 8 have a height of 40, measured from the holding plate 6, which is greater than the sum of the height of the cavity 38 and the height 42 of the first tool plate 18 (each measured in the longitudinal direction L). In short, the guide pins 8 have an excess length.

[0065] In order to optimally close the mold 12, the guide pins 8 are designed in this case such that they deflect when they hit the second tool plate 20. Two possible configurations are described below.

[0066] In a first embodiment (not shown), the guide pins 8 are each compressible in the longitudinal direction L and are compressed before or while the first tool plate 18 and the second tool plate 20 are placed on top of one another. The holding plate 6 itself is not moved relative to the first tool plate 18, nor are the guide pins 8 themselves moved, but merely compressed.

[0067] In a second embodiment ( Fig. 1 to 5), the holding plate 6 is moved away from the first tool plate 18 in the longitudinal direction L before or while the first tool plate 18 and the second tool plate 20 are placed on top of each other. This is shown in Fig. 3 and illustrated there by corresponding arrows 44. Thus, instead of compressing the guide pins 8 as in the first embodiment, they are displaced, here retracted, together with the holding plate 6 in the longitudinal direction L. Relatively speaking, the first tool plate 18 is thus displaced from the holding plate 6 along the guide pins 8 toward the second tool plate 20. The guide pins 8 are attached to the holding plate 6.

[0068] In both embodiments, the conductors 10 are also displaced on the guide pins 8 in the longitudinal direction L and in the direction of the tips 34 of the guide pins 8, if necessary.

[0069] In Fig. 12 is a picture of the wiring harness 2 from Fig. 10 is shown in perspective view, which was manufactured according to the method of the invention. In Fig. 13 is a picture of the wiring harness 2 from Fig.12 in a plan view, with the cable set 2 still in the second tool plate 20. List of reference symbols 2 electrical wiring harness 4 Mounting device 6 Holding plate 8 Guide pin 10 ladders 12 mold tool 14 Passage opening 16 Potting compound 18 first tool plate 20 second tool plate 22 Cavity 24 Filling opening 26th level 28 Seal 30 plugs 32 Deepening 34 Tip (tapered section) 36 straight section 38 Height (of the cavity) 40 height (of the guide pin) 42 height (of the first tool plate) 44 Arrow L longitudinal direction S1 first step S2 second step (assembly) S3 third step S4 fourth step (pouring) S5 fifth step (demoulding) QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2012 205 020 A1

[0004] WO 2020 / 161047 A1

[0004]

Claims

[1] Method for producing an electrical wiring harness (2), a. wherein a mounting device (4) is provided which has a holding plate (6) and one or more guide pins (8) arranged on the holding plate (6), b. wherein one or more conductors (10) are mounted according to a laying pattern and for this purpose at least a part of the conductors (10) is guided around the guide pins (8), c) wherein a molding tool (12) is provided, d. wherein the forming tool (12) and the holding plate (6) are moved towards each other, e. wherein the conductors (10) are cast with a casting compound (16) which is directed onto or into the mold (12) and then cured, so that the casting compound (16) and the conductors (10) form a composite in which the conductors (10) are fixed according to the laying pattern, f. wherein the assembly is removed from the holding plate (6) and pulled off the guide pins (8). [2] Method according to claim 1, wherein the forming tool (12) has a passage opening (14) for each of the guide pins (8), wherein the guide pins (8) are each guided through one of the passage openings (14). [3] Method according to claim 2, wherein the molding tool (12) has a first tool plate (18) and a second tool plate (20), wherein the first tool plate (18) has the through-openings (14), wherein the first tool plate (18) is placed on the holding plate (6) before the conductors (10) are mounted, wherein the first tool plate (18) and the second tool plate (20) are placed on top of each other after the conductors (10) have been mounted and before they are cast with the casting compound (16), wherein the first tool plate (18) and the second tool plate (20) enclose a cavity (22) in which the conductors (10) are arranged and into which the potting compound (16) is poured. [4] Method according to claim 3, wherein the conductors (10) are held by the guide pins (8) such that the conductors (10) are spaced apart from the two tool plates (18, 20). [5] Method according to claim 3 or 4, wherein the mounting device (4) and the first tool plate (18) are turned over after mounting the conductors (10) and before casting, so that the through-openings (14) are located above the conductors (10), wherein at most casting compound (16) is fed into the molding tool (12) until it reaches the through-openings (14). [6] Method according to one of claims 3 to 5, wherein the guide pins (8) each extend in a longitudinal direction (L), wherein the guide pins (8) protrude further from the first tool plate (18) than the cavity (22) is high measured in the longitudinal direction (L). [7] Method according to claim 6, wherein the guide pins (8) are each compressible in the longitudinal direction (L) and are compressed before or while the first tool plate (18) and the second tool plate (20) are placed on top of one another. [8] Method according to claim 6, wherein the holding plate (6) is moved away from the first tool plate (18) in the longitudinal direction (L) before or while the first tool plate (18) and the second tool plate (20) are placed on top of one another. [9] Method according to one of claims 1 to 8, wherein the composite is also removed from the mold (12). [10] Method according to one of claims 1 to 8, wherein the molding tool (12) remains wholly or partially connected to the composite when removed from the holding plate (6). [11] Method according to one of claims 1 to 10, wherein the guide pins (8) each have a tapered, in particular conical or truncated cone-shaped tip (34). [12] Method according to one of claims 1 to 11, wherein the molding tool (12) has at least one recess (32) into which a plug (30) is inserted, in particular in a form-fitting manner, wherein at least one of the conductors (10) is fastened to the plug (30). [13] Method according to one of claims 1 to 12, wherein the casting compound (16) is poured into the mold (12) with an injection pressure in the range of 0 bar to 10 bar. [14] Method according to one of claims 1 to 13, wherein the potting compound (16) is a cast polyamide, hot melt, epoxy resin, silicone or polyurethane. [15] Electrical wiring harness (2) manufactured according to a method according to one of claims 1 to 14.

Images