Protective cover for sensors relating to automotive engineering, and production method for a protective cover

Abstract

The invention relates to a protective cover for sensors relating to automotive engineering, which protective cover is designed as a moulded part having heating elements (1) injection moulded from a plastic (11), and connection points (3) for the heating elements (1) for connecting a power supply. According to the invention, a plug connector is provided, which comprises a contacting element and a connection sleeve (5), which is integrally moulded on the moulded part, wherein the contacting element is formed by a printed circuit board (6) crossed by electrical contacts (8), which are connected, on a side of the printed circuit board (6) facing the connection points (3), to the connection points (3) by means of an electrically conductive adhesive (10) and are electrically contacted, on a side of the printed circuit board (6) facing away from the connection points (3), to contact pins (4), which project from the printed circuit board (6) and are framed by the connection sleeve (5). The invention also relates to a method for producing a protective cover and to the use of the protective cover.

Description

[0001] Protective cover for vehicle technology sensors and

[0002] Manufacturing process for a protective cover

[0003] The invention relates to a protective cover for sensors in automotive technology, which is designed as a molded part with heating elements injection-molded from a plastic and connection points for the heating elements for the connection of a power supply, according to the preamble of claim 1, and to a manufacturing method for a protective cover according to claim 18.

[0004] In automotive technology, sensors such as cameras, radar, and lidar sensors are used with protective covers that can be heated using heating elements. The protective covers are designed as molded parts in which heating elements are embedded. The heating elements ensure that specific temperature ranges are maintained for proper sensor function.

[0005] Typically, heating elements are inserted into an injection mold during the production of protective covers and overmolded or back-injected with plastic. An area around the electrode connection points is kept free of material to provide soldering points for connecting a power supply. During the installation of such a heatable molded part, the connection points can be connected to the power supply cables via solder joints.

[0006] The installation of heated protective covers of the known type is therefore associated with assembly effort. Furthermore, the materials used for the electrodes and connection points are sometimes difficult to solder, such as silver-based pastes for silver tracks, also known as silver lacquer. The poor solderability of silver lacquers sometimes impairs contact or necessitates the abandonment of silver lacquers.

[0007] DE 10 2019 106 865 A1 discloses a method for producing a plastic part from a plastic film or plate, having at least one heating wire arranged in the plastic part. In order to avoid a hole in the plastic part intended for contacting the at least one heating wire, the at least one heating wire can be electrically contacted via at least one contact socket or similar electrical connecting element arranged on a flat side of the plastic part. For this purpose, the at least one heating wire arranged in the plastic part is stripped of paint or similarly exposed in a contacting area before, in a subsequent method step, the at least one heating wire is electrically contacted with the electrical connecting element in the exposed contacting area.

[0008] A disadvantage of the known solution is that first the electrical connection means must be applied to the plastic plate or film and then the at least one heating wire with its at least one exposed or still to be exposed contact area must be placed on the electrical connection means in order to be subsequently soldered.

[0009] US 2021 / 0037610A1 discloses a body component with sensors in automotive technology, which is designed as a molded part with a plurality of heating elements overmolded with a plastic and connection points for the plurality of heating elements for the connection of a power supply.

[0010] The disadvantage of the known solution is that the molded part consists of two plastic components. The first component comprises a support and contact pins as well as heating elements, and the second component comprises a connecting sleeve, with the two plastic components subsequently being joined together.

[0011] One object of the invention is to avoid at least one of the disadvantages of the prior art. In particular, the aim of the invention is to provide plastic molded parts that are easier to assemble and enable better contact.

[0012] A protective cover for sensors in automotive technology according to the invention is designed as a molded part with a plurality of heating elements injection-molded from a plastic material and connection points for the plurality of heating elements for connecting a power supply. At least one connector is provided, which comprises a contacting element and a connection sleeve molded onto the molded part. The contacting element is formed by at least one carrier element, the at least one carrier element being crossed by electrical contacts.

[0013] The plastic molded part thus has a plug connector with a contacting element and a connecting sleeve, into which a corresponding or complementarily shaped plug for connecting a power supply can be easily plugged. The production of a soldered connection can therefore be omitted when installing the plastic molded parts, which simplifies the assembly work for the protective covers according to the invention. The connecting sleeve is molded onto the plastic molded part and is manufactured at the same time as the molded part in the injection molding process. The molded part can be manufactured in the injection molding process by means of overmolding, back-injection, overmolding or other injection molding techniques or can include other processes in which the components are embedded in plastic.The electrical contacts run transversely through the at least one carrier element, so that they can be contacted on at least two sides and form an electrical connection through the at least one carrier element, for example to create a reliable electrical connection for the heating elements or for sensor data through the at least one carrier element.

[0014] The at least one carrier element is preferably cuboid-shaped and can have structured conductive surfaces on the top and bottom sides, which are separated by at least one insulating layer, for example a plastic, and form electrically conductive connections only at defined locations on the at least one carrier element by means of the electrical contacts between the top and bottom sides. For example, the top side is a side facing away from the connection points and the bottom side is a side facing the connection points. The at least one carrier element is compact and easy to process further. Furthermore, the at least one carrier element is suitable for being equipped with electrical contacts and for having dimensional stability during the production of the protective cover in an injection molding process.

[0015] In particular, the at least one carrier element is designed as a printed circuit board, so that the contacting element is formed by at least one printed circuit board, wherein the at least one printed circuit board is crossed by electrical contacts. The printed circuit board is conventionally made of FR4 or, as a flexible printed circuit board, of polyimide or PET. Alternatively, other carrier elements made of PEN, PC, PET, polyimide, or ceramic substrates are suitable.

[0016] The multiple heating elements of the molded parts are manufactured, for example, as flat heating elements that are applied to an electrically insulating carrier film, for example made of polycarbonate or polyethylene or PET, as conductive tracks, in particular metal tracks, such as silver tracks, that run, for example, in a meandering or circular pattern between two connection points. The silver tracks can be covered with an electrically insulating protective lacquer layer. A power supply can be connected to the connection points so that current flows through the silver tracks and they are thereby heated.

[0017] In particular, the silver tracks are formed as silver-based pastes, also known as silver lacquer, which are applied in viscous form to the carrier film at room temperature by screen printing in the desired arrangement and thermally cured, thus enabling cost-effective production. Since soldering of the contacting elements is omitted, the use of silver-based pastes is possible in the protective cover according to the invention.

[0018] Alternatively, the metal tracks are formed as metal-based pastes, for example, copper-based pastes, which are also referred to as metal lacquers. These pastes are applied in viscous form at room temperature to the carrier film in the desired arrangement by screen printing and then thermally cured. Alternatively, the electrically conductive tracks are formed as conductive pastes, for example, carbon-based pastes, which are also referred to as carbon lacquers. These pastes are applied in viscous form at room temperature to the carrier film in the desired arrangement by screen printing and then thermally cured.

[0019] Alternatively or additionally, resistance elements and electrodes are arranged on a carrier foil. The electrodes connect the resistance elements to connection points for a power supply, allowing current to flow through the resistance elements. The resistance elements represent an electrical resistance in which current is converted into heat, and in this application thus form the desired heat source. These resistance elements can, for example, have a PTC effect (positive, preferably non-linear temperature coefficient of ohmic resistance), whereby intrinsically stable heating elements can be created that regulate at a specific temperature.

[0020] Preferably, the electrical contacts on a side of the at least one carrier element facing the connection points are connected to the connection points via an electrically conductive material. Thus, the at least one carrier element is electrically contacted to the connection points and connected in a dimensionally stable and temperature-resistant manner.

[0021] In particular, the electrically conductive material is an electrically conductive adhesive. The contacting element is prepared before being inserted into the injection mold by bonding the at least one carrier element to the connection points of the heating elements using the electrically conductive adhesive. The type of connection between the at least one carrier element and the connection points has proven to be crucial because, during the injection molding process, high temperatures and high pressure act on the injection-molded parts for a short time. An adhesive connection has proven to be ideal because it has sufficient elasticity to compensate for thermally induced relative movements between the at least one carrier element and the connection points of the heating elements due to different expansions.

[0022] In particular, the at least one carrier element can consist of a plurality of structured metal elements, e.g. stamped parts, which are spaced apart from one another and which are individually connected to the plurality of electrical contacts by means of the electrically conductive material.

[0023] Preferably, the electrical contacts are electrically contacted by contact pins on a side of the at least one carrier element facing away from the connection points. The plastic molded part thus comprises a connector with contact pins and a connection sleeve, into which a corresponding or complementarily shaped plug for connecting a power supply can be easily inserted. The contact pins not only provide the electrical contact but also provide mechanical stability to the plug connection.

[0024] Preferably, the contact pins protrude from the at least one carrier element. The contact pins are designed as projections that protrude from the at least one carrier element. This simplifies the assembly of the protective cover, since the contact pins can be easily inserted into an opening of a complementary plug.

[0025] In particular, the contact pins are framed by the connection sleeve, so that they are at least protected from external mechanical influences, such as impacts. Furthermore, this prevents the contact pins from being bent during installation of the protective cover.

[0026] The connector preferably has at least two, in particular three, contact pins. In the case of two contact pins, the heating elements can be contacted with an external power supply, and the protective cover can be heated. In the case of at least three contact pins, at least one sensor arranged in the protective cover can be contacted, and its measurement data can be derived from the protective cover. There can also be more than three contact pins, so that several sensors arranged in the protective cover can be contacted and thus read out.

[0027] Preferably, the electrical contacts project beyond the at least one carrier element on the side facing the connection points, ensuring reliable contact between the electrical contacts and the connection points. Particularly when manufacturing the protective cover with the connector using an injection molding process, the high pressures in the injection molding tool and its dimensional tolerances can lead to displacement of the protective cover components. Such displacements therefore do not affect the contact between the electrical contacts and the connection points.

[0028] The electrical contacts are preferably surrounded by a protective layer in their peripheral regions. The protective layer preferably serves as a spacer between the at least one carrier element and the electrically conductive material or the connection points. As a result, the at least one carrier element rests on the connection points over a larger area, enabling improved production of the connector in the protective cover during injection molding. The protective layer can, for example, be made from a protective lacquer that can be printed onto the at least one carrier element.

[0029] In particular, the thickness of the protective layer corresponds to the height of the electrical contacts projecting above the at least one carrier element. This ensures that the at least one carrier element rests snugly on the connection points, enabling improved production of the connector in the protective cover during injection molding.

[0030] The electrical contacts of the at least one carrier element, for example in circuit boards, are generally made of copper and traverse the at least one carrier element, forming tracks and fields on the surfaces of the at least one carrier element that project slightly beyond the at least one carrier element on both sides. On the side of the at least one carrier element facing the connection points, the problem can arise that the comparatively sharp-edged copper contacts can sever or damage the connection points, which are printed, for example, with a silver paste, during the injection molding process. Therefore, it is preferably proposed that the electrical contacts project beyond the side of the at least one carrier element facing the connection points and be framed in their peripheral regions by a protective layer whose thickness corresponds to the height of the electrical contacts projecting beyond the at least one carrier element.

[0031] Preferably, the at least one carrier element is provided, on its side facing away from the connection points, with a layer of an adhesion promoter that promotes injection molding with the plastic. The use of an adhesion promoter is generally known in injection molding. In the present case, the adhesion promoter promotes the bond between the at least one carrier element and the injection molding compound during the injection molding process. The choice of adhesion promoter depends on the at least one carrier element and the plastic used.

[0032] Preferably, the electrically conductive material connecting the electrical contacts to the connection points has anisotropic conductivity. The anisotropy of the conductivity maximizes the current density of the conducted current in the direction relevant for contacting, namely in the direction perpendicular to the at least one support element, transverse to the at least one support element, and can either be a material-related property of the material or be achieved by structured application of the material to the side of the at least one support element facing the connection points.

[0033] In particular, the electrically conductive material connecting the electrical contacts to the connection points has an anisotropic conductivity with a maximum conductivity in the direction perpendicular to the at least one carrier element. The anisotropy of the electrically conductive material is particularly advantageous for embodiments in which the

[0034] Heating elements are arranged on a carrier foil, and their connection points on the carrier foil form adjacent contact areas. In this case, the application of the electrically conductive material to the contact areas could pose a risk of a short circuit, which is reduced or eliminated by the anisotropic conductivity with maximum conductivity in a direction perpendicular to at least one carrier element.

[0035] Preferably, the anisotropic conductivity is a material-related property of the electrically conductive material. If the anisotropy is a material-related property of the electrically conductive material, the electrically conductive material can be applied over the entire surface of the contact areas because the flow of current between two adjacent connection points, i.e., parallel to at least one carrier element, is excluded due to the material.

[0036] The anisotropic conductivity is preferably due to the structured application of the electrically conductive material to the side of the at least one carrier element facing the connection points. If the electrical conductivity of the electrically conductive material is not already anisotropic due to the material, the anisotropic conductivity can also be achieved by the structured application of the electrically conductive material to the side of the at least one carrier element facing the connection points, in that each connection point is connected via the electrically conductive material to the electrical contact of the at least one carrier element assigned to it, but not to the other connection points.

[0037] The heating elements are preferably arranged on a further, in particular flat, carrier element. For the production of a molded part according to the invention, the heating elements are arranged on a flat carrier, for example on the carrier film mentioned above.

[0038] In particular, the heating elements are applied to the additional carrier element by screen printing, making them easy to manufacture. Preferably, the at least one carrier element has openings extending perpendicular to the at least one carrier element. These openings allow the injection-molding compound to pass through the at least one carrier element during the injection-molding process, thus ensuring a better bond with the carrier film of the heating elements.

[0039] Preferably, at least one temperature sensor is present, which is arranged on the at least one carrier element. In the case of film-shaped heating elements, temperature sensors are sometimes used which are arranged on the carrier film. The temperature sensors (such as SMD components) are identified by bulges on the carrier film after the injection molding process. Within the scope of the present invention, the at least one carrier element of the contacting element can be used as a carrier for temperature sensors, so that their arrangement on the carrier film can be dispensed with. The temperature sensors can, however, also be printed onto the carrier film. These printed sensors have a significantly lower thickness (<30pm), which means that bulges can be avoided.

[0040] Preferably, at least one of the contact pins is provided for the at least one temperature sensor. In particular, the electrical signal of the at least one temperature sensor can be picked up via this contact pin. A separate contact pin can thus be provided for this temperature sensor, via which the electrical signal of the temperature sensor can be picked up. It is therefore proposed that the connector have at least three contact pins. Two contact pins are provided for the power supply of the heating element, and one contact pin, for example, for a temperature sensor.

[0041] Preferably, at least one ice sensor, in particular a capacitive detecting one, is present and is arranged on at least one of the heating elements. Within the scope of the present invention, the at least one carrier element of the contacting element can be used as a carrier for the ice sensor, so that its arrangement on the carrier film can be dispensed with. The at least one ice sensor locally detects when the temperature of the phase transitions in the molded part falls below the freezing point. If there are several ice sensors, the detection of the temperature falling below the freezing point can take place locally on the sensor cover. However, the ice sensors can also be printed on the carrier film. These printed sensors have a significantly lower thickness (<30pm), which means that bulges can be avoided.

[0042] Preferably, at least one of the contact pins is provided for the at least one ice sensor. In particular, the electrical signal of the at least one ice sensor can be picked up via this contact pin. A further contact pin can be provided for an ice sensor arranged on the heating element.

[0043] Preferably, at least one electrical component from the group of capacitive sensors, pressure sensors, a light source, or an electrochromic layer is present, and is connected to at least one of the contact pins. In this case, the connector would have four contact pins. Thus, in principle, any number of contact pins can be provided for any number of sensors. These can be, for example, capacitive sensors, pressure sensors, etc. Furthermore, other active elements, such as light sources or electrochromic layers, can also be integrated.

[0044] A manufacturing method according to the invention for producing a protective cover, in particular a protective cover as described here, comprises at least the following steps: a. arranging electrical contacts on at least one carrier element; b. fastening contact pins to the electrical contacts; c. arranging the at least one carrier element at connection points for heating elements which are arranged on a further carrier element, at least one contacting element being formed; d. injection-molding the at least one contacting element with plastic in a tool of an injection-molding process, at least one connection sleeve being co-molded which frames in particular the plurality of contact pins. The plastic molded part thus has a plug connector with a contacting element and a connection sleeve, into which a corresponding orA complementarily shaped plug for connecting a power supply can be easily inserted. The creation of a soldered connection can therefore be omitted when installing the plastic molded parts, which simplifies the assembly effort of the protective covers according to the invention. The connection sleeve is molded onto the plastic molded part and is manufactured simultaneously with the molded part in the injection molding process.

[0045] Preferably, in step a, a protective layer is applied to one side of the at least one carrier element around the electrical contacts. The protective layer preferably serves as a spacer between the at least one carrier element and the electrically conductive material or the connection points. Thus, the at least one carrier element rests on the connection points over a larger area, enabling improved production of the connector in the protective cover during injection molding.

[0046] Preferably, in step b, an adhesion promoter is applied to the side of the at least one carrier element with the contact pins. In the present case, the adhesion promoter promotes the bond between the at least one carrier element and the injection-molding compound during the injection-molding process. The choice of adhesion promoter depends on the at least one carrier element and the plastic used.

[0047] Preferably, in step c, the at least one carrier element is fastened to the connection points of the heating elements using an electrically conductive material. In particular, the at least one carrier element is glued to the connection points of the heating elements using an electrically conductive adhesive. On the side of the at least one carrier element facing away from the connection points, the contact pins are fastened to the at least one carrier element and are electrically and mechanically connected to the connection points via the electrical contacts and the electrically conductive adhesive.The at least one carrier element with the contact pins, which is glued to the connection points, is placed in the injection molding tool and injection-molded with the plastic in such a way that the heating element with the connection points and the at least one carrier element is embedded in the plastic, but the contact pins remain free of material at their free ends and protrude from the molded part. As already mentioned, the connection sleeve, which frames the exposed contact pins, is also molded. Together with the connection sleeve, reliable contact can be ensured via the contacting element.

[0048] One inventive use of the protective cover described here is to detect fogging and / or snow adhesion to the protective cover, or to protect against icing in the mobility sector and / or as an interior heater, in particular as a heater for liquid tanks. The present protective cover can also be used to heat plastic interior components in the mobility sector or to heat tanks for liquids of all kinds.

[0049] The molded part therefore has a plug connector with contact pins and a connection sleeve into which a correspondingly shaped plug for connecting a power supply can be easily plugged. The production of a soldered connection can therefore be omitted when installing the molded parts, which simplifies the assembly work for the protective covers according to the invention. The connection sleeve is molded onto the molded part and is produced at the same time as the molded part in the injection molding process. The contacting element is prepared before being inserted into the injection mold by at least one carrier element being bonded to the connection points of the heating elements using an electrically conductive material. The type of connection between the carrier element and the connection point has proven to be crucial because the injection molding process briefly exposes the injection-molded parts to high temperatures and high pressure.

[0050] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described with reference to the drawings. The list of reference symbols, as well as the technical content of the patent claims and figures, is an integral part of the disclosure. The figures are described coherently and comprehensively. Identical reference symbols denote identical components; reference symbols with different indices indicate functionally identical or similar components.

[0051] The invention is explained in more detail with reference to exemplary embodiments in the following figures. The list of reference symbols is an integral part of the disclosure.

[0052] Positional information such as "top", "bottom", "right" or "left" refers to the respective illustrations and is not to be understood as limiting.

[0053] Although the invention is illustrated and described in detail by means of the figures and the associated description, this illustration and this detailed description are to be understood as illustrative and exemplary and not as limiting the invention. It is understood that those skilled in the art can make changes and modifications without departing from the scope of the following claims. In particular, the invention also encompasses embodiments having any combination of features mentioned or shown above for various aspects and / or embodiments.

[0054] The invention also encompasses individual features in the figures, even if they are shown there in connection with other features and / or not mentioned above. Furthermore, the term "comprise" and derivatives thereof does not exclude other elements or steps. Likewise, the indefinite article "a" or "an" and derivatives thereof does not exclude a plurality. The functions of several features listed in the claims can be fulfilled by a single unit. The terms "essentially," "about," "approximately," and the like in connection with a property or value, in particular, also precisely define the property or value. All reference symbols in the claims are not to be understood as limiting the scope of the claims. The invention will be explained in more detail below using exemplary embodiments with the aid of the accompanying drawings. These show:

[0055] Fig. 1 is a perspective view of an embodiment of a molded part according to the invention,

[0056] Fig. 2 is a schematic view to explain a first manufacturing step for the contacting element, in which in particular a protective lacquer is applied to the side of the board facing the connection points,

[0057] Fig. 3 is a schematic view to explain a further manufacturing step for the contacting element, in which contact pins are attached to the side of the board facing away from the connection points and an adhesion promoter is applied to this side,

[0058] Fig. 4 is a schematic view to explain a further manufacturing step for the contacting element, in which the circuit board is glued to the connection points of the heating elements,

[0059] Fig. 5 is a schematic view to explain a final manufacturing step for the contacting element, in which the contacting element is overmolded with plastic while forming the connection sleeve, and the , and

[0060] Fig. 6 is a view of the circuit board from above.

[0061] Firstly, reference is made to Fig. 1, which shows an embodiment of a molded part according to the invention with heating elements 1 embedded therein, which are shown in dashed lines. In the exemplary embodiment shown, the heating elements 1 are arranged on a flat carrier 2 (see Figs. 4 and 5) and applied to the flat carrier 2 by screen printing. The heating elements 1 are made, for example, from a hardened, silver-based paste, which is applied in viscous form to the carrier film in web form by screen printing with the desired profile and is thermally cured. The web-shaped heating elements 1 open into connection points 3 (see Figs. 4 and 5) for the connection of a power supply, so that current can flow through the heating elements 1. The heating elements 1 represent an electrical resistance in which electricity is converted into heat and thus form the desired heat source in the present application.

[0062] For connecting a power supply, the molded part is manufactured with a plug connector which has contact pins 4 and a connection sleeve 5. A correspondingly shaped plug for connecting a power supply can be easily plugged into this plug connector, the contact pins 4 being part of a contacting element which will be described in more detail. The production of a soldered connection can therefore be omitted when installing the molded parts, which simplifies the assembly work for the molded parts according to the invention. The connection sleeve 5 is molded onto the molded part and is manufactured at the same time as the molded part in the injection molding process, as will be explained below.

[0063] The contacting element is prepared before being inserted into the injection mold, as shown in FIGS. 2 to 4. Fig. 2 shows a schematic view of a first production step of the production method for the contacting element, wherein a circuit board 6 with electrical contacts 8 can be seen first, as shown schematically in Fig. 7. The circuit board 6 is made in the conventional way from FR4 or as a flexible circuit board from polyimide or PET and is crossed by the electrical contacts 8 ("through-plated"). The electrical contacts 8 of the circuit board 6 are generally made from copper and form tracks and fields on the surfaces of the circuit board 6, which slightly project beyond the circuit board 6 on both sides. On the side of the circuit board 6 facing the later connection points 3 - in Fig.2 the lower side of the circuit board 6 - a protective layer 7 made of a protective lacquer is applied, for example printed, the thickness of which approximately corresponds to the height of the electrical contacts 8 projecting above the circuit board 6. The protective layer 7 protects the connection points 3, which are usually also printed, from damage caused by the comparatively sharp-edged copper contacts during the injection molding process. Fig. 3 shows a schematic view to explain a further manufacturing step for the contacting element, in which contact pins 4 are attached to the side of the circuit board 6 facing away from the connection points 3 and an adhesion promoter is applied to this side. The contact pins 4 are soldered to the electrical contacts 8, for example. In the exemplary embodiment shown, the plug connector has four contact pins 4.Two of these contact pins 4 are provided for the power supply of the heating element 1, another contact pin 4, for example, for a temperature sensor, and another contact pin 4, for example, for an ice sensor. The adhesion promoter promotes the bond between the circuit board 6 and the injection molding compound during the injection molding process. The choice of the adhesion promoter 9 depends on the circuit board 6 and the plastic used.

[0064] Fig. 4 shows a schematic view to explain a further manufacturing step for the contacting element, in which the circuit board 6 is glued to the connection points 3 of the heating elements 1 using an electrically conductive adhesive 10. The type of connection created between the circuit board 6 and the connection points 3 of the heating elements 1 has proven to be crucial, since high temperatures and high pressure act on the overmolded parts for a short time during the injection molding process. An adhesive connection has proven to be ideal, since it has sufficient elasticity to compensate for thermally induced relative movements between the circuit board 6 and the connection points 3 of the heating elements 1 due to different expansions.On the side of the circuit board 6 facing away from the connection points 3, the contact pins 4 are attached to the circuit board 6 and are electrically and mechanically connected to the connection points 3 via the electrical contacts 8 and the electrically conductive adhesive 10.

[0065] With regard to the adhesive 10 for the connection points 3, it is proposed that the adhesive 10 connecting the electrical contacts 8 to the connection points 3 has anisotropic conductivity with a maximum conductivity in the direction perpendicular to the circuit board 6. The anisotropy of the conductivity maximizes the current density of the conducted current in the direction relevant for contacting, namely in the direction perpendicular to the circuit board 6, crossing the circuit board 6, and can either be a material-related property of the adhesive 10 or be achieved by structured application of the adhesive 10 to the side of the circuit board 6 facing the connection points 3, as already explained.

[0066] The circuit board 6 with the contact pins 4, which is glued to the connection points 3, is then placed in the tool of the injection molding process and overmolded with plastic 11 in such a way that the heating element 1 with the connection points 3 and the circuit board 6 is embedded in the plastic 11, but the contact pins 4 remain at least partially free of material and protrude from the molded part with their free ends (see Fig. 5). As already mentioned, the connection sleeve 5, which frames the exposed contact pins 4, is also molded. Together with the connection sleeve 5, reliable contact can be ensured via the contacting element. As can be seen in Fig. 6, the circuit board 6 has openings 12 running perpendicular to the circuit board 6. These openings 12 allow the injection molding compound to pass through the circuit board 6 during the injection molding process and thus provide a better bond with the flat carrier 2 of the heating elements 1.

[0067] In the case of heating elements 1 arranged in a planar manner, temperature sensors are sometimes used which are arranged on the planar carrier 2. In the context of the present invention, the circuit board 6 of the contacting element can be used as a carrier for temperature sensors, so that their arrangement on the planar carrier 2 can be dispensed with. An advantageous placement of a temperature sensor or another SMD (surface mounted device) component is indicated in Fig. 6 by the circled area, where, through appropriate design of the electrical contacts 8, the contact areas of two electrical contacts 8 come very close, namely that for the ground, which is the left outer contact 8 in Fig. 6, and a contact pin 4 for the temperature sensor, which is assigned to the left inner contact 8 in Fig. 6. The right inner contact 8 in Fig. 6 could, for example, be provided for the contact pin 4 of an ice sensor.The right outer contact 8 shown in Fig. 6 would be intended for the positive pole of the power supply in the illustrated embodiment.

[0068] The molded part thus has a plug connector with contact pins 4 and a connection sleeve 5. A correspondingly shaped plug for connecting a power supply can be easily plugged into this plug connector. The production of a soldered connection can therefore be omitted when installing the molded parts, which simplifies the assembly effort of the molded parts according to the invention. The connection sleeve 5 is molded onto the molded part and is manufactured simultaneously with the molded part in the injection molding process. With the aid of the invention, plastic molded parts are thus provided that are easier to assemble and enable better contact.

[0069] The manufacturing method for producing the protective cover disclosed in FIGS. 2 to 5 generally comprises the following steps: a. arranging electrical contacts 8 on at least one carrier element 6; b. attaching contact pins 4 to the electrical contacts 8; c. arranging the at least one carrier element 6 at connection points 3 for heating elements 1, which are arranged on a further carrier element 2, whereby at least one contacting element is formed; d. injection-molding the at least one contacting element with plastic in a tool of an injection-molding process, whereby at least one connection sleeve 5 is co-molded, which frames the plurality of contact pins 4. List of reference symbols

[0070] 1 heating elements

[0071] 2 flat supports / additional support element

[0072] 3 connection points

[0073] 4 contact pins

[0074] 5 Connection sleeve

[0075] 6 Carrier element / circuit board

[0076] 7 Protective layer

[0077] 8 Electrical contacts

[0078] 9 Adhesion promoters

[0079] 10 Electrically conductive material / adhesive

[0080] 11 plastic

[0081] 12 breakthroughs

Claims

Patent claims:

1. Protective cover for vehicle sensors, designed as a molded part with several heating elements (1) and connection points (3) for the several heating elements (1) for connecting a power supply, injection-molded from a plastic (11), characterized in that a connector is provided which comprises a contacting element and a connection sleeve (5) molded onto the molded part, wherein the contacting element is formed by at least one carrier element (6), in particular by a circuit board, wherein the at least one carrier element (6) is crossed by electrical contacts (8).

2. Protective cover according to claim 1, characterized in that the electrical contacts (8) on a side of the at least one carrier element (6) facing the connection points (3) are connected to the connection points (3) via an electrically conductive material, in particular an adhesive (10).

3. Protective cover according to claim 1 or 2, characterized in that the electrical contacts (8) are electrically contacted with contact pins (4) on a side of the at least one carrier element (6) facing away from the connection points (3).

4. Protective cover according to claim 3, characterized in that contact pins (4) protrude from the at least one support element (6) and are in particular framed by the connecting sleeve (5).

5. Protective cover according to claim 4, characterized in that the connector has at least two, in particular three, contact pins (4).

6. Protective cover according to one of the preceding claims, characterized in that the electrical contacts (8) extend beyond the side of the at least one support element (6) facing the connection points (3). Protective cover according to one of the preceding claims, characterized in that the electrical contacts (8) are framed in their circumferential regions by a protective layer (7), the thickness of which corresponds in particular to the height of the electrical contacts (8) projecting above the at least one support element (6). Protective cover according to one of the preceding claims, characterized in that the at least one support element (6) is provided on its side facing away from the connection points (3) with a layer of an adhesion promoter (9) that promotes injection molding with the plastic (11). Protective cover according to one of the preceding claims, characterized in that the electrical contacts (8) The electrically conductive material connecting the connection points (3) has an anisotropic conductivity, with a maximum conductivity, in particular, in the direction perpendicular to the at least one support element (6). . Protective cover according to claim 9, characterized in that the anisotropic conductivity is a material-related property of the electrically conductive material. . Protective cover according to claim 9 or 10, characterized in that the anisotropic conductivity is caused by a structured application of the electrically conductive material on the side of the at least one support element (6) facing the connection points (3). . Protective cover according to any one of the preceding claims, characterized in that the heating elements (1) are arranged on a further, in particular planar, support element (2) and are applied to the further support element (2), in particular by screen printing.Protective cover according to one of the aforementioned claims, characterized in that the at least one support element (6) extends in a perpendicular direction to the at least. a support element (6) has openings (12) running through it.

14. Protective cover according to one of the preceding claims, characterized in that at least one temperature sensor is provided which is arranged on the at least one support element (6).

15. Protective cover according to claim 14, characterized in that at least one of the contact pins (4) is provided for the at least one temperature sensor, via which in particular the electrical signal of the at least one temperature sensor can be detected.

16. Protective cover according to one of the preceding claims, characterized in that at least one ice sensor is provided which is arranged on at least one of the heating elements (1).

17. Protective cover according to claim 16, characterized in that at least one of the contact pins (4) is provided for the at least one ice sensor, via which in particular the electrical signal of the at least one ice sensor can be detected.

18. Protective cover according to one of the preceding claims, characterized in that at least one electrical component from the group of capacitive sensors, pressure sensors, a light source or an electrochromic layer is present, and which is connected to at least one of the contact pins ( 4 ).

19. Manufacturing method for producing a protective cover, in particular a protective cover according to any one of claims 1 to 18, wherein the manufacturing method comprises at least the following steps: a. Arranging electrical contacts (8) on at least one carrier element (6); b. Attaching contact pins (4) to the electrical contacts (8); c. Arranging the at least one support element (6) at connection points (3) for heating elements (1) which are arranged on a further support element (2), wherein at least one contacting element is formed; d. Injection molding the at least one contacting element with plastic in a tool of an injection molding process, wherein at least one connection sleeve (5) is formed, which in particular frames the several contact pins (4).

20. Manufacturing method according to claim 19 characterized in that in step a. a protective layer (7) is applied to one side of the at least one carrier element (6) around the electrical contacts (8).

21. Manufacturing method according to claim 19 or 20 characterized in that in step b. an adhesion promoter (9) is applied to the side with the contact pins (4) of the at least one carrier element (6).

22. Manufacturing method according to one of claims 19 to 21 characterized in that in step c. the at least one support element (6) is attached to the connection points (3) of the heating elements (1) using an electrically conductive material, in particular by means of an electrically conductive adhesive (10).

23. Use of the protective cover according to any one of claims 1 to 18 as a means of detecting condensation and / or snow adhesion on the protective cover, or as protection against icing of the protective cover in the mobility sector and / or as interior heating, in particular as heating of liquid tanks.

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