Heating element for heating a component of a motor vehicle, connector for use in such a heating element and radome for a motor vehicle antenna with such a heating element

Abstract

Heating element (10) for heating a component (32) of a motor vehicle, the heating element (10) comprising a carrier film (1) made of an electrically insulating material and conductor tracks (3) made of an electrically conductive material applied thereto or embedded therein, wherein a plug connector (4) with at least two electrical contacts (5) is applied to one side of the carrier film (1), the electrical contacts (5) of the plug connector are contacted with the conductor tracks (3) of the heating element (10), and the side of the carrier film (1) on which the plug connector (4) is applied is overmolded with a material (12) for producing the component (32) in such a way that the plug connector (4) is permanently fastened to the carrier film (1) by the component (32) after the material (12) has hardened, characterized in that the connector (4) has at least one opening (6) which is positioned and designed to be able to check a welded and / or soldered connection between the conductor tracks (3) and the electrical contacts (5) of the connector (4).

Description

The present invention relates to a heating element for heating a component of a motor vehicle, in particular a rear or front windshield, a radome, or a part of an illumination device of the motor vehicle, preferably a cover pane or a projection optics of a motor vehicle headlight. The heating element comprises a carrier film made of an electrically insulating material and conductor tracks made of an electrically conductive material applied thereto or embedded therein. A plug connector with at least two electrical contacts is applied to one side of the carrier film. The electrical contacts of the plug connector are contacted with the conductor tracks of the heating element and the side of the carrier film on which the plug connector is applied is over-molded with a material for producing the component in such a way that the plug connector is non-detachably fastened to the carrier film by the component after the material has cured.Finally, the invention also relates to a radome in which an antenna of a motor vehicle is arranged for protection against mechanical and / or chemical influences, wherein the radome has a heating element of the stated type.A heating element of the type mentioned at the beginning is known, for example, from DE 10 2015 218 876 A1. Furthermore, DE 11 2019 001 650 T5 discloses a heating element for use in the field of vision of camera-based safety systems in automobiles. Finally, DE 20 2018 106 646 U1 discloses an electrical connection element for use in a heating element for heating a window of a motor vehicle.In a rear or front window heating system known from the prior art, heating tracks made of electrically conductive material are printed on the window. When current flows through the tracks, heat is generated, which is used for defrosting the pane. For example, at the ends of the heater traces, copper pads are applied to the wafer and electrical contacts soldered thereon. In some cases, an electrical contact is also soldered directly onto a thickened heating track. A sealing or a protection of the connecting or soldering location is not provided, since the connecting location is generally located in the vehicle interior and therefore does not have any external influences (for example. This is subject to weathering (e.g. extreme temperatures, wind, ice), physical influences (e.g. impacts, shocks) or chemical influences (e.g. moisture, salt water).However, the solder joint is disadvantageously subjected to mechanical stress when a contact plug is plugged onto the electrical contacts and when the contact plug is pulled. When contacting the window heating (plugging the contact plug onto the electrical contacts), there is in particular no mechanical relief of the soldering location. Incidentally, the soldering is generally performed manually and is therefore susceptible to errors rather than a fully automated soldering process. However, such a device is generally not used in front or rear window heaters for producing the soldered connections between the electrical contacts and the heating tracks. A simple unlocking and thus a simple loosening of the contacts (pulling of the contact plug) is not provided, so that force is again exerted on the soldering location. Furthermore, a connector position assurance (CPA) is not present. A connector position assurance (CPA) serves to ensure a contact position of a plug housing on a corresponding plug housing. The CPA is an extra plastic part which is combined with the socket housing and can only be confirmed after complete plugging onto the counterpart (pin housing). Thus, an only partial insertion of the socket housing onto the counterpart and a fault associated therewith can be reliably prevented.A radome, also a radome, is a closed protective cover that protects antennas for measurements (e.g., radar antennas) or for data transmissions (e.g., directional radio antennas) from external mechanical and chemical influences such as wind or rain, but without influencing and / or impairing the transmitting / receiving radiation passing through the antennas. Radomes are preferably made of plastic, for example. Polyurethane manufactured. Radomes can also be made of glass fiber, quartz or chemical resins. Moisture on the radome, in particular in conjunction with low temperatures around and below the freezing point (0° C.), can influence or impair the transmission and / or reception radiation passing through the radome of the antenna arranged in the radome. It is therefore known to heat the radomes if necessary.In radomes, for example, heating wires applied to a carrier foil are welded directly onto an electrical contact. The electrical contact, the heating wires and the carrier foil form a separate assembly. The sealing of the connection point between heating wires and electrical contact is effected by means of an adhesive. The heater wires are relatively thin and preferably have a diameter of less than 150 microns. Particularly preferably, the heating wires are thinner than the human hair (<0.06 to 0.08 mm or <60 to 80 μm), so that the transmission and / or reception radiation of the antennas arranged in the radomes is not influenced or impaired, or at most to an acceptable extent.Radomes are found on permanently installed large radar systems (e.g. flight protection radar) and on ships. Smaller radomes are used in radio links, in satellite antennas (e.g. for satellite navigation or communication) on motor vehicles or small ships and also for meteorological measuring devices. The radomes take up the wind load from the antenna system (which is frequently designed to be movable for the purpose of tracking) and protect the antennas on ships and motor vehicles from the corrosive effects of sea or salt water (for example in the case of salted roadway in winter). The nose cladding of aircraft which have a navigation or weather radar in the nose of the aircraft is also called radome.Radomes keep weather influences (e.g. wind, precipitation), mechanical influences (e.g. shocks, blows) and / or chemical influences (e.g. moisture, salt water) from the antennas in particular. In aircraft and radomes arranged in the front region of motor vehicles, air resistance must be able to withstand. A common use of radomes in motor vehicles is for protecting radar antennas or other antennas in the front region of the motor vehicle (e.g. in the radiator grille), wherein the radar antennas or other antennas are used, for example. The control may be part of an adaptive cruise control (ACC).In the realization of the heating wire contacting in radomes, the electrical contacts must be positioned very accurately in the injection molding tool in order to subsequently be able to fit over the plastic housing of the radome. Since the contacts are unprotected, great care must be taken that they are not contaminated, scratched or even bent. This makes the construction of the injection molding tool very complicated. In addition, a further component, namely the plastic housing of the plug connector, must be produced and connected to the aforementioned assembly (electrical contact heating wire carrier film). The contact or soldering and / or welding point between the electrical contact and the heating wires must be filled with an auxiliary substance (for example. The adhesive) can be sealed since it is located outside. The geometry of the electrical contacts must be matched exactly to the injection molding process so that they can be held and fixed there. Furthermore, the contacts must be matched in length and dimensions to a specific plug connector. A free selection of the plug connector is thus not possible. If one wishes to change to another plug-in system for the purpose of cost or changed requirements, new contacts must be produced.It is also known from the prior art to heat a cover pane of a motor vehicle lighting device, in particular of a vehicle headlight, by means of a heating element (cf. JP 2007-242 291 A). Finally, it is also known to heat a projection lens of a light module of a motor vehicle lighting device, in particular a projection lens of a projection module of a vehicle headlight, by means of a heating element (cf. DE 10 2020 124 774).Proceeding from the described prior art, it is an object of the present invention to configure and further develop a heating element of the type mentioned at the beginning such that the contacting of the conductor tracks of the heating element with an energy supply of the motor vehicle is improved.To achieve this object, a heating element having the features of claim 1 is proposed. In particular, starting from the heating element of the type mentioned at the beginning, it is proposed that the plug connector has at least one opening which is positioned and designed to be able to check a welded and / or soldered connection between the conductor tracks and the electrical contacts of the plug connector.The component that can be heated by the heating element is, for example, a rear or front windshield, a radome or a part of an illumination device of the motor vehicle, preferably a cover pane or a projection optics of a motor vehicle headlight. According to the invention, the carrier film which carries the electrical conductor tracks of the heating element is therefore overmolded with the material for producing the heatable component. As a result, the carrier film and thus the entire heating element practically become an integral part of the heatable component. In order to improve the contacting of the heating element, a plug connector is provided which is arranged on the carrier film and the electrical contacts of which are contacted with the conductor tracks of the heating element. To a certain extent, in order to realize a strain relief, the plug connector is likewise at least partially over-molded or over-molded with the material of the component during over-molding of the carrier film, such that the plug connector is held firmly by the component after the material of the component has cured. When establishing and releasing an electrical contact via the plug connector, the connection points between the electrical contacts of the plug connector and the electrical conductor tracks of the heating element are protected from excessively high loading.The electrical conductor tracks of the heating element and the plug connectors do not have to be arranged on the same side of the carrier film. By means of a feedthrough opening in the carrier film and a welded connection of the conductor tracks to the electrical contacts of the plug connector, the invention can also be realized if the electrical conductor tracks and the plug connector are arranged on different sides of the carrier film.The non-detachable fastening can only be released by damage to the plug connector, the heatable component and / or the heating element.The plug connector has at least one opening which is positioned and designed to be able to check a welded and / or soldered connection between the conductor tracks and the electrical contacts of the plug connector. In particular, the at least one opening is positioned and configured to check the soldered connection between the contact surfaces on the carrier film and the electrical contacts of the plug connector. Preferably, a separate opening is provided for each of the electrical contacts or the contact surfaces. Particularly preferably, the at least one opening of the plug connector is formed in a radially outwardly protruding circumferential flange section of the plug connector.According to an advantageous development of the invention, it is proposed that, before the electrical contacts of the plug connector are contacted with the conductor tracks of the heating element, contact surfaces are formed from an electrically conductive material on the side of the carrier film on which the plug connector is applied and are welded to the conductor tracks, and the electrical contacts of the plug connector are contacted with the contact surfaces. The electrical contacts of the plug connector are contacted with the contact surfaces, for example, by soldering.According to a preferred embodiment, it is proposed that, before the application of the plug connector to the carrier film, at least one fastening point, in particular at least one adhesive point, is applied to the side of the carrier film on which the plug connector is applied, and the plug connector, after the application to the carrier film, is held on the carrier film by the at least one fastening point, as long as the carrier film has not yet been overmolded with the material for producing the component and / or the material for producing the component has not yet cured. The adhesive spot or spots can be produced by means of any desired adhesive. The adhesive point or points thus form a securing of the position of the plug connector during assembly and as long as the plug connector is not yet finally non-detachably fastened by means of the cured material of the heatable component.In radomes for antennas that emit electromagnetic radiation in the range of 76-77 GHz, the conductor tracks should have a diameter (in the case of heating wires) or a width (in the case of flat conductor tracks) of less than 0.3 mm (300 μm). Such thin conductor tracks are particularly well suited for heating such components through which radiation (e.g. optical radiation, radar radiation, ultrasonic radiation) passes, since the thin conductor tracks practically do not influence and / or impair a see-through or a passage of the radiation through the component, or at most to an acceptable extent. This makes the heating element particularly well suited for heating the radome, for example, by the antenna arranged in the radome during operation. Radar radiation passes through. The conductor tracks preferably have a diameter of less than 80 μm, particularly preferably of less than 60 μm.The conductor tracks are preferably designed as heating wires introduced into the electrically insulating material of the carrier film. In this case, the conductor tracks are therefore not applied to the carrier film, for example, by sputtering (for example, sputter deposition methods using ITO), by means of patterning or by vacuum vapor deposition by applying an electrically conductive material, but rather as heating wires made of an electrically conductive material, for example. Copper is introduced into the material of the carrier film. The heating wires can be introduced during or after the production of the carrier film.It is particularly preferred if the conductor tracks, in particular in the form of heating wires, are introduced into the electrically insulating material of the carrier film by means of an ultrasonic wire laying technique. The ultrasonic wire laying technique enables a rapid and precise introduction of heating wires into the carrier film. With the aid of an ultrasonic generator, electrical oscillations at approximately 70 kHz are generated, which are converted by a piezoelectric crystal into mechanical oscillations. A sonotrode can reinforce these oscillations, as a result of which molecular and boundary surface friction occurs on the carrier film. The friction between sonotrode, heating wire and carrier film or film surface leads to partial melting of the surface. This makes it possible to place the heating wire into the molten film material via a wire lead-through in the sonotrode and thus to integrate it directly into the carrier film. The sinking distance of the wire is regulated by the contact pressure of the sonotrode on the surface. Precise force control is advantageous for a stable process. Thanks to the pressure control, a robot can also actively react to uneven surfaces and adapt its path or the orientation of a wire laying head accordingly. Thus, even concave and convex contours can be processed with the 3D wire laying method.The electrical conductor tracks of the heating element are preferably welded to the electrical contacts of the plug connector. In particular, it is proposed that the conductor tracks are welded to the contact surfaces. Prior to the application of the plug connector to the carrier film, solder can be applied to the contact surfaces, and after the application of the plug connector to the carrier film, the electrical contacts of the plug connector can be soldered to the contact surfaces by means of the solder. It is particularly preferred if the electrical contacts of the plug connector are soldered to the contact surfaces by induction.According to another advantageous development of the invention, it is proposed that the plug connector has a hollow encircling collar section, in the interior of which the electrical contacts of the plug connector run. A wall of the collar section preferably runs substantially perpendicular to a surface extension of the carrier film and / or substantially parallel to a longitudinal extension of the electrical contacts. A corresponding plug connector, which is connected to an energy source of the motor vehicle, for example a vehicle battery, or a control and regulation unit of the motor vehicle, and has corresponding electrical contacts, can be accommodated by the collar section or can accommodate the collar section itself. In this case, the electrical contacts of the plug connectors come into contact with one another.The encircling collar section or another part of the plug connector preferably has a connector position securing means (so-called connector position assurance; CPA) for ensuring correct contacting of the electrical contacts of the plug connectors. On the one hand, the CPA can ensure correct contacting of the electrical contacts of the one plug connector with the corresponding electrical contacts of the other plug connector. In addition, the CPA can also have a securing or locking element in order to prevent unintentional detachment of the two plug connectors from one another.Furthermore, according to another preferred embodiment of the invention, it is proposed that the plug connector has a radially outwardly projecting circumferential flange section. After the carrier film has been over-molded, the flange section can be at least partially over-molded with the material for producing the component.Alternatively or additionally, the flange section can serve as a press edge during the overmolding of the carrier film with the material for producing the component in order to seal the plug connector with respect to an injection molding tool used for overmolding the carrier film. This has the advantage that, on the one hand, uncontrolled overmoulding of the welding or soldering points between the electrical contacts of the plug connector and the conductor tracks of the heating element is prevented and, on the other hand, the injection-molding tool can be configured relatively simply and economically.Preferably, the collar portion extends on one side of the flange portion substantially perpendicularly from the flange portion. A side of the flange portion opposite the collar portion can serve as a standing or bearing surface of the plug connector, with which the latter is placed on the carrier film. This standing or bearing surface can come into contact with the at least one fastening point formed on the carrier film, in particular with the at least one adhesive point, so that the plug connector is held on the carrier film immediately after being placed on the carrier film thanks to the fastening or adhesive points until the material of the heatable component at least partially overmolding the flange section has cured.The object underlying the present invention is also achieved by a plug connector having the features of claim 20. In particular, starting from the plug connector of the type mentioned at the beginning, it is proposed that the plug connector be designed for use in a heating element according to the invention.Finally, the object on which the present invention is based is also achieved by a radome having the features of claim 21. In particular, starting from the radome of the type mentioned at the beginning, it is proposed that the radome has a heating element according to the invention. Preferably, the side of the carrier film of the heating element on which the plug connector is applied is over-molded with a material for producing the radome, so that the plug connector is non-detachably fastened to the carrier film by the radome after the material has cured.Further features and advantages of the present invention are explained in more detail below with reference to the figures. The following are shown: FIG. 1 shows a detail of a heating element according to the invention in a plan view; FIG. 2 shows a cross section through the detail of the heating element from FIG. 1 in a first assembly step; FIG. 3 shows a cross section through the detail of the heating element from FIG. 2 in a subsequent assembly step; FIG. 4 shows a plug connector according to the invention for use in a heating element according to FIGS. 1 to 3 in a perspective view; FIG. 5 shows different views of the plug connector according to the invention from FIG. 4 (FIG. 5 a: from the front, 5 b: right, 5 c: left, 5 d: top, 5 e: bottom); and FIG. 6 shows a front region of a motor vehicle having two radomes according to the invention which are equipped with a heating element according to the invention.The present invention is based on a heating element for heating a component of a motor vehicle, in particular a rear or front windshield, a radome, or a part of a lighting device of the motor vehicle, preferably a cover pane or a projection optics of a motor vehicle headlight. The heating element comprises a transparent foil made of an electrically insulating material and conductor tracks made of an electrically conductive material applied thereto or embedded therein. Such a heating element for a projection lens of a light module of a motor vehicle headlight is known, for example, from DE 10 2020 124 774 of the same applicant as the present application. With regard to the construction and production of the heating element, reference is expressly made to DE 10 2020 124 774 and the content of this publication is expressly incorporated in the present application.FIG. 1 shows a detail of a heating element 10 according to the invention. The heating element 10 comprises a carrier film 1 made of an electrically insulating material and conductor tracks 3 made of an electrically conductive material applied thereto or embedded therein.The carrier film 1 is preferably made of a plastic. The film 1 preferably has a thickness in the range from 100 to 600 μm, preferably in the range from 200 to 500 μm, very particularly preferably in the range from about 350 μm. The carrier film 1 is preferably flexible enough that it can adapt to a curvature or slight curvature of a heatable component 32.An example will be discussed in more detail below in which the heating element 10 serves for heating a radome 32. The carrier film 1 does not necessarily have to be transparent. However, depending on the type of antenna arranged in the radome, it should be as well transmissive as possible for electromagnetic waves, for example in the ultrasonic range (about 20 kHz to 10 MHz) or in the radar range (about 20-30 GHz or 76-77 GHz). However, if the heating element 10 is used for heating a component through which optical rays fall, for example a cover pane or a projection lens of a motor vehicle headlight or a front or rear window of a motor vehicle, the carrier film should also be transparent. A transparent carrier film 1 can consist, for example, of a transparent polycarbonate (PC).The electrical conductor tracks 3 are preferably designed as heating wires. In this case, the conductor tracks 3 are therefore not applied to the electrically conductive material of the carrier film, for example, by sputtering (for example, sputter deposition methods by means of ITO), by means of patterning or by vacuum vapor deposition, but rather as separate heating wires made of an electrically conductive material, for example. Copper is formed. The separate heating wires 3 are applied or introduced onto or into the carrier film 1.The heating wires 3 preferably have a diameter in the range of 10-300 μm, preferably in the range of 30-150 μm, very particularly preferably in the range of 40-120 μm, without electrical insulation. The heating wires 3 preferably have a diameter of less than 300 μm, in particular of less than 80 μm, particularly preferably of less than 60 μm, so that the transmission and / or reception radiation of the antennas arranged in the radomes 32 is not influenced or at most is influenced or impaired to an acceptable extent.The heating wires 3 are preferably introduced into the electrically insulating material of the carrier film 1. In this case, the conductor tracks are therefore not applied to the carrier film 1, but rather introduced into the latter. The heating wires 3 can be introduced during or after the production of the carrier film 1.The heating wires 3 can be introduced into the electrically insulating material of the carrier film 1 by means of an ultrasonic wire laying technique.FIG. 1 shows in particular a contacting region of the heating element 10, in which the conductor tracks 3 are contacted with electrical contacts 5 of a plug connector 4. A correspondingly designed other plug connector (not shown) can be engaged with the plug connector 4, the electrical contacts of which are then connected to the electrical contacts 5 of the plug connector 4. The electrical contacts of the other plug connector are connected, for example, to an energy source of the motor vehicle, for example a vehicle battery, or to a control and regulation unit of the motor vehicle. Thus, the heating wires 3 of the heating element 10 are connected to electrical energy in the contacting region shown.The invention proposes that the plug connector 4 with the at least two electrical contacts 5 is applied to one side of the carrier film 1, that the electrical contacts 5 of the plug connector 4 are contacted with the conductor tracks 3 of the heating element 10 and that the side of the carrier film 1 on which the plug connector 4 is applied is overmolded with a material 12 for producing the component 32 (cf. FIG. 3 ) in such a way that the plug connector 4 is non-detachably fastened to the carrier film 1 by the component 32 after the material 12 has cured. In this way, the contacting of the heating element 10 can be significantly improved. In particular, when establishing and releasing an electrical contacting of the heating element 10 via the plug connector 4, the connection points (soldering and / or welding points) between the electrical contacts 5 of the plug connector 4 and the electrical conductor tracks 3 of the heating element 10 are protected from excessively high loading.The non-detachable fastening of the plug connector 4 to the carrier film 1 by means of the material 12 for producing the heatable component 32 can be achieved, for example, in that, when the carrier film 1 is over-molded, a part of the material 12 penetrates into openings in the plug connector 4 and cures there. It would likewise be conceivable for a part of the material 12 also to overspray and cure a part of the plug connector 4 during overmolding of the carrier film 1 (cf. FIG. 3 ).FIG. 1 shows an assembled state where the carrier film 1 has not yet been overmolded with the material 12 of the component 32 and consequently the plug connector 4 has not yet been fastened to the carrier film 1. The assembled state shown in FIG. 1 is shown in FIG. 2 in cross section.In the examples shown, the electrical conductor tracks 3 of the heating element 10 and the plug connector 4 are arranged on the same side of the carrier film 1. However, this does not necessarily have to be so. By means of a feedthrough opening in the carrier film 1 and a welded connection of the conductor tracks 3 to the electrical contacts 5 of the plug connector 4, the invention can also be realized if the electrical conductor tracks 3 and the plug connector 4 are arranged on different sides of the carrier film 1.It is proposed that, before the electrical contacts 5 of the plug connector 4 are contacted with the conductor tracks 3 of the heating element 10, contact surfaces 2 are formed from an electrically conductive material on the side of the carrier film 1 on which the plug connector 4 is applied and are contacted with the conductor tracks 3. The contact surfaces 2 are designed, for example, as copper pads. The conductor tracks 3 can be welded, for example, to the contact surfaces 2. The electrical contacts 5 of the plug connector 4 are in contact with the contact surfaces 2. This can be effected, for example, by soldering.Prior to arranging the plug connector 4 on the carrier film 1, solder can be applied (dispensed) to the contact surfaces 2. After the arrangement of the plug connector 4 on the carrier foil 1, the electrical contacts 5 of the plug connector 4 can be soldered to the contact surfaces 2 by means of the solder. It is particularly preferred if the electrical contacts 5 of the plug connector 4 are soldered to the contact surfaces 2 by induction. The electrical contacts 5 of the plug connector 4 preferably have an L-shape, wherein a leg of the L is formed on the underside of the plug connector 4 for contacting with the contact surfaces 2.Before arranging the plug connector 4 on the carrier film, at least one fastening point 14 (cf. FIGS. 2 and 3 ) can be applied to the side of the carrier film 1 on which the plug connector 4 is applied. The fastening point 14 can be formed, for example, as an adhesive point which is applied to the carrier film 1 by means of an adhesive. Preferably, several fastening points 14 are applied. After the arrangement of the plug connector 4 on the carrier film 1, the latter is held on the carrier film 1 by the at least one fastening point 14 as long as the carrier film 1 has not yet been overmolded with the material 12 for producing the component 32 (cf. FIG. 2 ) and / or the material 12 for producing the component 32 has not yet been cured (cf. FIG. 3 ).The fastening point or points 14 thus form a securing of the position of the plug connector 4 during assembly and as long as the plug connector 4 is not yet finally non-detachably fastened by means of the cured material 12 of the heatable component 32.It is proposed that the plug connector 4 has a hollow encircling collar section 16, in the interior of which the electrical contacts 5 of the plug connector 4 run. A wall of the collar portion 16 preferably runs substantially perpendicular to a surface extension of the carrier film 1 (cf. FIGS. 2 and 3 ) and / or substantially parallel to a longitudinal extension of the electrical contacts 5. The electrical contacts 5 of the plug connectors 4 thereby come into contact with one another.The encircling collar section 16 preferably has a connector position assurance (CPA) 18 for ensuring complete and correct contacting of the electrical contacts 5 of the plug connectors 4. In addition, the CPA 18 can also have or form a securing or locking element in order to prevent, on the one hand, a complete engagement of the two plug connectors 4 and / or an unintentional release of the two plug connectors 4 from one another. The CPAs 18 can also be formed on a part of the plug connector 4 other than the collar portion 16.It is further proposed that the plug connector 4 has a radially outwardly projecting circumferential flange section 20. After the carrier film 1 has been over-molded, the flange section 20 can be at least partially over-molded with the material 12 for producing the component 32.Alternatively or additionally, the flange section 20 can serve as a press edge during the overmolding of the carrier film 1 with the material 12 for producing the component 32 in order to seal the plug connector 4 with respect to an injection molding tool (not shown) used for overmolding the carrier film 1. This has the advantage that, on the one hand, uncontrolled overmoulding of the welding or soldering points between the electrical contacts 5 of the plug connector 4 and the conductor tracks 3 of the heating element 10 is prevented and, on the other hand, the injection moulding tool can be configured relatively simply and economically.The collar portion 16 preferably extends on one side of the flange portion 20 substantially perpendicularly from the flange portion 16. This standing or bearing surface can come into contact with the at least one fastening point 14 formed on the carrier film 1, in particular with the at least one adhesive point, so that the plug connector 4 is held on the film 1 immediately after being placed on the film 1 thanks to the fastening or adhesive point or points 14 until the material 12 of the heatable component 32 at least partially overmolding the flange section 20 has cured.The plug connector 4 has at least one opening 6, which is positioned and designed in such a way that a welded and / or soldered connection between the conductor tracks 3 and the electrical contacts 5 of the plug connector 4 can be checked. The at least one opening 6 of the plug connector 4 is preferably provided in order to check a soldered connection between the contact surfaces 2 and the electrical contacts 5 of the plug connector 4. Preferably, the at least one opening 6 is formed in the radially outwardly protruding circumferential flange section 20 of the plug connector 4. In the example shown, two openings 6 are shown, one for each electrical contact 5 and for each contact surface 2, respectively. Of course, only one opening 6 can also be provided, in particular if this is sufficiently large to be able to optically capture both electrical contacts 5 or both contact surfaces 2.FIG. 6 shows a front region 30 of a motor vehicle having two radomes 32 according to the invention which are equipped with a heating element 10 according to the invention. In the example shown, the front region 30 includes the front end of a hood 34 and, aligned with a vertical vehicle center plane, a grille 36 centrally. In front-mounted internal combustion engines, the grille 36 typically serves for supplying cooling air during the travel of the motor vehicle. In rear engine or electric motor vehicles, the grille 36 may be provided for design reasons alone. Arranged to the side of the grille 36 are headlights 38 with headlights 40. In addition, a bumper 42 and a front spoiler (not shown) may also be arranged in the front region 30.The radomes 32 each form a protective cover or protective cover which protects antennas for measurements (e.g. radar antennas) arranged behind them from external mechanical and chemical influences such as wind, rain, insects, but without influencing and / or impairing the transmitting / receiving radiation 44 of the antennas passing through. Radomes 32 are preferably made of plastic, for example. Polyurethane manufactured. Radomes 32 can also be manufactured from glass fiber, quartz or chemical resins. Moisture on the radome 32, in particular in conjunction with low temperatures around and below the freezing point (0° C.), can influence or impair the transmission and / or reception radiation 44 passing through the radome 32 of the antenna arranged in the radome 32. Therefore, the radomes 32 are provided with a heating element 10 according to the invention.In the example shown, the antennas associated with radomes 32 transmit, for example. Radar beams emit and are part of a distance control temperature (so-called adaptive cruise control). Of course, the antennas assigned to radomes 32 may also emit other radiation and / or be assigned to other motor vehicle functionalities. It would furthermore be conceivable for the radomes 32 to also be arranged at any other desired locations in the motor vehicle, for example on the vehicle roof, if the radomes 32 are assigned satellite antennas as part of a satellite navigation system (e.g. GPS, Galileo) or of a satellite communication system (e.g. iridium, starlink). It would likewise be conceivable to also provide only one radome 32 in the front region 30 of the vehicle.For manufacturing the heatable component 32 of a motor vehicle, the present invention proposes the following steps:providing a carrier film 1, preferably made of a plastic, in particular polycarbonate (PC),introducing heating wires 3 into the foil 1, preferably by means of an ultrasonic wire-laying technique,applying contact areas 2, in particular in the form of copper pads, to the side of the carrier film 1 on which the plug connector 4 is subsequently also arranged, preferably adhering the contact areas 2,contacting the heating wires 3 with the contact surfaces 2, in particular by welding,dispensing of solder on the contact surfaces 2,applying at least one fastening point 14, in particular in the form of at least one adhesive point, to the side of the carrier film 1 on which the plug connector 4 is subsequently also arranged,placing the plug connector 4 on the carrier film 1, so that a standing or bearing surface of the plug connector 4 is held on the carrier film 1 by the at least one fastening point 14,contacting the electrical contacts 5 of the plug connector 4 with the contact surfaces 2, in particular by soldering, very particularly by induction soldering,overmoulding of the side of the carrier film 1 on which the plug connector 4 is arranged and at least part of the plug connector 4, in particular part of a flange portion 20 of the plug connector 4, with a material 12 of the heatable component 32, andcuring the material 12 of the heatable component 32.

Claims

Heating element (10) for heating a component (32) of a motor vehicle, the heating element (10) comprising a carrier film (1) made of an electrically insulating material and conductor tracks (3) made of an electrically conductive material applied thereto or embedded therein, wherein a plug connector (4) having at least two electrical contacts (5) is applied to one side of the carrier film (1), the electrical contacts (5) of the plug connector are contacted with the conductor tracks (3) of the heating element (10), and the side of the carrier film (1) to which the plug connector (4) is applied is over-injected with a material (12) for producing the component (32) in such a way that the plug connector (4) is non-detachably fastened to the carrier film (1) by the component (32) after the material (12) has cured, characterized in that the plug connector (4) has at least one opening (6) which is positioned and formed, a welded and / or soldered connection between the conductor tracks (3) and the electrical contacts (5) of the plug connector (4) can be checked.Heating element (10) according to claim 1, wherein the heating element (10) is configured to heat a rear or front window, a radome, or a part of a lighting device of the motor vehicle.Heating element (10) according to claim 2, wherein the heating element (10) is configured to heat a cover pane or a projection optical unit of a motor vehicle headlight.Heating element (10) according to one of the preceding claims, wherein, before the electrical contacts (5) of the plug connector (4) are contacted with the conductor tracks (3) of the heating element (10), contact surfaces (2) are formed or applied from an electrically conductive material on the side of the carrier film (1) on which the plug connector (4) is applied and are contacted with the conductor tracks (3), and the electrical contacts (5) of the plug connector (4) are contacted with the contact surfaces (2).Heating element (10) according to one of the preceding claims, wherein, before the application of the plug connector (4) to the carrier film (1), at least one fastening point (14) is formed or applied on the side of the carrier film (1) on which the plug connector (4) is applied, and the plug connector (4) is held on the carrier film (1) by the at least one fastening point (14) after the application to the carrier film (1), as long as the carrier film (1) has not yet been overmolded with the material (12) for producing the component (32) and / or the material (12) for producing the component (32) has not yet been cured.The heating element (10) of claim 5, wherein the at least one attachment point (14) comprises at least one adhesion point.Heating element (10) according to one of the preceding claims, wherein the conductor tracks (3) have a diameter of less than 300 μm.Heating element (10) according to claim 7, wherein the conductor tracks (3) have a diameter of less than 80 μm.Heating element (10) according to claim 8, wherein the conductor tracks (3) have a diameter of less than 60 μm.Heating element (10) according to one of the preceding claims, wherein the conductor tracks (3) are formed as heating wires introduced into the electrically insulating material of the carrier film (1).Heating element (10) according to one of the preceding claims, wherein the conductor tracks (3) are introduced into the electrically insulating material of the carrier film (1) by means of an ultrasonic wire-laying technique.Heating element (10) according to one of the preceding claims, wherein the conductor tracks (3) are welded to the electrical contacts (5) of the plug connector (4).Heating element (10) according to Claims 4 and 12, wherein the conductor tracks (3) are welded to the contact surfaces (2).Heating element (10) according to claim 13, wherein prior to the application of the plug connector (4) to the carrier film (1), solder is applied to the contact surfaces (2), and after the application of the plug connector (4) to the carrier film (1), the electrical contacts (5) of the plug connector (4) are soldered to the contact surfaces (2) by means of the solder.Heating element (10) according to claim 14, characterised in that the electrical contacts (5) of the plug connector (4) are soldered to the contact surfaces (2) by induction.Heating element (10) according to one of the preceding claims, wherein the plug connector (4) has a hollow collar portion (16), in the interior of which the electrical contacts (5) of the plug connector (4) run, wherein a wall of the collar portion (16) runs substantially perpendicular to a surface extension of the carrier film (1) and / or substantially parallel to a longitudinal extension of the electrical contacts (5).Heating element (10) according to one of the preceding claims, wherein the plug connector (4) has a circumferential flange section (20) which projects radially outwards and which is at least partially overmoulded after overmoulding of the carrier film (1) with the material (12) for producing the component (32).Heating element (10) according to one of the preceding claims, wherein the plug connector (4) has a radially outwardly protruding circumferential flange section (20) which serves as a press edge during the overmolding of the carrier film (1) with the material (12) for producing the component (32) in order to seal the plug connector (4) with respect to an injection molding tool for overmolding the carrier film (1).Heating element (10) according to claim 17 or 18, wherein the at least one opening (6) of the plug connector (4) is formed in the radially outwardly protruding circumferential flange section (20).A connector (4) comprising at least two electrical contacts (5) for use in a heating element (10) according to any of the preceding claims.Radome (32) in which an antenna of a motor vehicle is arranged for protection against mechanical and / or chemical influences, wherein the radome (32) has a heating element (10) according to one of Claims 1 to 19, and the side of the carrier film (1) of the heating element (10) on which the plug connector (4) is applied is over-injected with a material (12) for producing the radome (32), such that the plug connector (4) is non-detachably fastened to the carrier film (1) by the radome (32) after the material (12) has cured.

Images