Electronic module, electronic component and method for protecting and embedding electronic components

Abstract

The present invention relates to an electronic module, to an electronic component comprising the electronic module, and to a method for embedding and protecting electronic components, in particular for protection against the effects of temperature. An interaction between the geometric design of an injection-moulded body in combination with the chemical composition of the injection-moulded body enables a more uniform distribution of heat within the injection-moulded body to be ensured.

Description

[0001] DTS: 40033. TUR. P110PC

[0002] ELECTRONIC COMPONENT, ELECTRONIC COMPONENT AND METHOD FOR PROTECTING AND EMBEDDING ELECTRONIC COMPONENTS

[0003] The present invention relates to an electronic assembly, an electronic component comprising the electronic assembly, and a method for embedding and protecting electronic components, in particular in the form of electronic sensors, from environmental influences, especially for protection against temperature effects.

[0004] Electronic components, for example in the form of inductive sensors, capacitive sensors, pressure sensors, gas sensors, temperature sensors, humidity sensors, ultrasonic sensors, vibration sensors or UV sensors, have been known in the state of the art for a long time.

[0005] The electronic components typically have a cylindrical hollow tube as their outer housing, which is filled with multiple electronic components. The space between the electronic components and the inner wall of the hollow tube is usually filled with a one-component or two-component potting compound to ensure adequate protection of the electronic components from environmental influences such as dirt and moisture. At the same time, the potting compound also stabilizes the electronic components against shocks and vibrations by fixing them within the housing. Common potting compounds used include polyurethane foams, polyurethane compacts, silicone, and / or epoxy resins.

[0006] The unpublished patent application with application number DE102023117285.9 describes an electronic assembly comprising a housing, a connector, an electronic circuit board, a sensor board, and a front cap. The housing accommodates the connector, the electronic circuit board, the sensor board, and the front cap sequentially from its rear to its front. The front of the housing is closed and / or sealed by means of crimped edges around the front cover, thus securing the connector, the electronic circuit board, and the sensor board inside the housing.

[0007] In one embodiment of the patent application cited above, the electronic circuit board and the sensor board can be overmolded with a thermoplastic shell. The contour of the overmolded shell can correspond to the inner contour of the housing. DTS: 40033. TUR. P110PC

[0008] Buffer zones that are not precisely defined can also be taken into account, which consider the coefficients of thermal expansion of the thermoplastic material.

[0009] To simplify the manufacturing of electronic components, it is also known to encapsulate the electronic components directly within the housing, with the outer housing serving as a mold and thus determining the shape of the encapsulated component. The encapsulated component then rests flush against the inside of the housing wall without any gaps.

[0010] German patent application DE10 2008 037 667 B4 discloses a method for embedding and protecting electronic circuits from environmental influences, as well as an electronic component manufactured according to this method. In the described method, the electronic circuit is placed in a potting mold and encased in a potting compound. The potting compound then hardens, and the hardened component can be removed from the mold. In the final step, the component is placed in a stable housing. The design of the component relative to the housing is such that raised features allow for a positive fit between the component and the housing's inner surfaces, while still providing clearance between the component and the housing to compensate for thermal expansion of the housing and / or the component.

[0011] In summary, DE10 2008 037 667 B4 describes a geometric concept for reducing the negative effects of temperature on electronic components within a housing. However, it has been found that despite the geometric design of the encapsulation body, damage to the electronic components can still occur under temperature exposure if there is an irregular heat distribution within the encapsulation body. With an irregular heat distribution, the geometrically created spaces between the housing and the encapsulation body cannot be fully utilized. This creates internal stresses within the encapsulation body, which also act on the electronic components enclosed within it and damage them.

[0012] Based on the aforementioned prior art, the object of the present invention is therefore to further develop an electronic component, particularly in the form of a sensor, in such a way that the pressure acting on the electronic components at elevated temperatures can be further reduced. This should result in, in particular, improved operational capability of the electronic assemblies at elevated temperatures. DTS: 40033. TUR. P110PC

[0013] To solve the problem, an electronic assembly, an electronic component, and a method for protecting and embedding electronic components are proposed in accordance with the attached independent claims.

[0014] The electronic assembly for manufacturing a sensor comprises an electronic circuit board and a sensor circuit board, as well as an electrically conductive connection, for example, in the form of a connector or a cable. The sensor circuit board and the electronic circuit board are electrically connected to each other. Furthermore, the electrically conductive connection, particularly in the form of a connector, and the electronic circuit board are also electrically connected to each other. The electrically conductive structure consisting of the sensor circuit board, the electronic circuit board, and the electrically conductive connection forms a composite electronic assembly.

[0015] According to the invention, the assembled electronic component is completely surrounded, at least along the circuit board, by an injection-molded body made of thermoplastic material. The injection-molded body has protrusions on its outer surface. These protrusions enable, at least in part, a force-fit connection of the injection-molded body to the inner surface of a housing as soon as the injection-molded body is inserted into the housing. At the same time, the protrusions allow for the formation of gaps (also called buffer zones) between the injection-molded body and the inner surface of the housing, which permit thermal expansion of the injection-molded body in the event of temperature exposure.

[0016] According to the invention, the injection molding body is made from a composition comprising at least one thermoplastic polymer and having a thermal conductivity of at least 0.2 W / m*K as measured according to ISO 22007-2 (2022 edition).

[0017] Through the interaction according to the invention between the geometric design of the injection mold in combination with the chemical composition of the injection mold, a more uniform heat distribution within the injection mold can be ensured, so that the buffer areas created by the geometric design of the injection mold are optimally utilized.

[0018] The electrically conductive connection between sensor board, electronics board and electrically conductive output can be created, for example, by soldering, especially by selective soldering.

[0019] The electrically conductive outlet can be in the form of a plug or a cable, preferably in the form of a plug. The plug can be manufactured as a separate element and, for example, has a plug housing in which one or more pins are provided, which ensure the plug functionality. DTS: 40033. TUR. P110PC

[0020] The connector, for example, makes contact with one end of the circuit board. The circuit board can be, for example, a planar element with electronic components mounted on it. At a second end of the circuit board, a sensor board can then be connected to the circuit board.

[0021] The raised areas on the outer surface of the injection mold preferably extend regularly over the entire outer surface of the mold. These raised areas can be designed as strip-like or linear raised areas extending transversely or longitudinally, preferably longitudinally, across the mold, or as singular raised areas. Corresponding geometric configurations are described in DE 10 2008 037 667 B4, the contents of which are hereby incorporated by reference.

[0022] In a particularly preferred embodiment of the invention, the protrusions on the cylindrical surface of the injection mold are designed as linear protrusions extending in the longitudinal direction (i.e., in the insertion direction) of the injection mold. The protrusions preferably extend over the entire length of the injection mold. Such strip-like protrusions extending along the longitudinal direction of the cylindrical surface are most easily achieved when the cross-section of the injection mold is polygonal and dimensioned such that its outer edges are in contact with the cylindrical inner circumference of a housing after insertion.

[0023] The number of polygon lines is selected depending on the desired size of the buffer zones. It is preferred that the polygon has an even number of vertices, such as 4, 6, 8, or 10. In a preferred embodiment of the invention, the cross-section of the injection mold has four vertices. The polygon lines can be straight or—if the volume of the buffer zones is to be increased—concave. A concave design of the polygon lines is preferred.

[0024] In a particularly preferred embodiment of the invention, the cross-section of the injection mold is cruciform. The cruciform cross-section of the injection mold enables good centering of the electronic component within the housing.

[0025] According to the invention, a composition is used for the production of the injection-molded part that contains at least one thermoplastic (also referred to as a thermoplastic material) processable by low-pressure injection molding. The composition has a thermal conductivity of at least 0.2 W / m*K to enable uniform heat distribution within the injection-molded part and thus ensure optimal utilization of the buffer zone created by the geometric shape of the injection-molded part. DTS: 40033. TUR. P110PC

[0026] Thermal conductivity is a property of the injection molding compound and describes the heat flow through the compound due to thermal conduction. The injection molding compound preferably has a thermal conductivity in the range of 0.2 to 1.1 W / m*K. Particularly preferably, the injection molding compound has a thermal conductivity in the range of 0.5 W / m*K to 1.1 W / m*K, and more preferably in the range of 0.8 W / m*K to 1.1 W / m*K. The thermal conductivity of the compound is determined at 24 °C using the method described in ISO 22007-2 (2022 edition).

[0027] The term thermoplastic polymer (or thermoplastic for short) as used in the present invention describes polymers that can be reversibly deformed within a specific temperature range. It is essential to the present invention that the thermoplastic polymer can be processed using low-pressure injection molding.

[0028] For the purposes of the present invention, the term "low-pressure injection molding process" refers to an injection molding process operating at low pressure, typically in the range of 0.5 to 200 bar at moderately elevated temperatures, usually in the range of 70 to 250 °C, in which the electronic components to be overmolded are placed in a mold and then overmolded. In contrast to the low-pressure injection molding process, typical injection molding requires a pressure of over 200 bar at 250 °C or higher. The low-pressure injection molding process thus offers the possibility of effectively sealing electronic components without subjecting them to external stress, which can reduce their service life. Preferably, the low-pressure injection molding process according to the present invention is carried out in a temperature range of 80 to 250 °C and a pressure range of 3 to 60 bar.

[0029] Thermoplastic materials suitable for low-pressure injection molding include polyamides, such as PA6 or PA66. Besides polyamides, various polyesters, such as poly(ethylene vinyl acetate), polyurethanes, and polyolefins, are also suitable.

[0030] Furthermore, so-called hot melt adhesives can also be used as thermoplastic polymers that can be processed by low-pressure injection molding. These are also known as low-pressure molding (LPM) hot melts. Within the scope of the present invention, LPM hot melts are particularly suitable those based on polyamides, polyesters, and polyolefins, such as polypropylene (PP) or polyethylene (PE), with those based on polyamides being especially preferred.

[0031] By using different thermoplastics, individual requirements for the injection molding body can be met with regard to flexibility, impact resistance, shock absorption, DTS: 40033. TUR. P110PC

[0032] Moisture resistance, sealing, UV protection, chemical resistance, color, transparency, and flammability are all taken into account. This ensures optimal adaptation to the specific requirements of the respective components.

[0033] To adjust the thermal conductivity of the injection mold composition, one or more fillers can be added. Inorganic or organic fillers can be used. The presence of fillers in the composition leads to improved thermal conductivity, increased dimensional stability, and heat resistance of the resulting injection mold. This results in a more uniform heat distribution within the injection mold and thus a reduction in localized pressure spraying on the electronic components. Suitable fillers include metal oxides, such as aluminum oxide, titanium oxide, boron oxide, zirconium oxide, tantalum oxide, silicon oxide, and mixtures thereof, with aluminum oxide being particularly preferred. Metal nitrides or carbides, such as aluminum nitride, boron nitride, silicon carbide, and mixtures thereof, can also be used.Graphite or so-called carbon nanotubes (CTNs) are also suitable. Mixtures of the aforementioned fillers can also be used.

[0034] The proportion of fillers in the composition is preferably 15 to 65 wt.%, for example 35 to 65 wt.%, preferably 40 to 65 wt.% based on the total weight of the composition.

[0035] Depending on the application, it can be advantageous for the injection-molded part to have a predetermined hardness. The hardness of a part can be specified as a characteristic value in the form of the Shore hardness D. It has been found that the injection-molded part has a Shore hardness D in the range of 5 to 85, preferably in the range of 15 to 65, and more preferably in the range of 25 to 50. The Shore hardness D is determined using the method described in ISO 868 / 15. By using an injection-molded part with a corresponding Shore hardness D, increased mechanical stability can be ensured, which has a beneficial effect on the assembly process. Furthermore, injection-molded parts with an increased Shore hardness D generate better counter-pressure against the press-fit tabs on the sheet metal ring of a connector, thereby achieving further stabilization during the joining process into the housing.A SHORE hardness D in the preferred range also results in a lower coefficient of thermal expansion, thereby achieving additional temperature stability during temperature cycling.

[0036] To reduce pressure loads on the electronic components, preferably injection-molded materials are used that have a coefficient of thermal expansion in the range of < DTS: 40033. TUR. P110PC in the temperature range of -40 °C to 100 °C.

[0037] exhibiting a coefficient of thermal expansion of 150 ppm / K. Preferably, the coefficient of thermal expansion is in the range of 15 to 150 ppm / K, more preferably in the range of 16 to 120 ppm / K.

[0038] Depending on the application, for example, when recesses for lighting diodes are to be provided in the injection mold, it can be advantageous for the composition to be highly viscous and / or have a high filler content. The use of a highly viscous composition has the advantage that the composition cannot penetrate small recesses, thus allowing for the targeted creation of recesses in the injection mold contour. The composition preferably has a melt viscosity greater than 5000 mPas, preferably greater than 7000 mPas at 210 °C.

[0039] According to the invention, the electronic component is completely surrounded by an injection-molded body, at least along the circuit board.

[0040] The thickness of the injection-molded coating on the circuit board can vary depending on the design of the electronic component. In particular, the coating thickness at the edges of the circuit board is at least 0.2 mm. Preferably, the coating thickness at the edges of the circuit board is in the range of 0.35 to 1.1 mm, more specifically in the range of 0.5 to 0.9 mm, and more preferably in the range of 0.6 to 0.8 mm. Using a corresponding coating thickness helps to ensure sufficient protection of the electronic components against dust, chemicals, and moisture.

[0041] In a further development of the invention, the injection mold encloses not only the electronic circuit board but also, at least in part, the sensor board. Here, the injection mold can surround the side of the sensor board facing the electronic circuit board and the edge of the sensor board. Additionally, the measuring side of the sensor board can also be enclosed by the injection mold . In an alternative embodiment, the injection mold terminates at the edge of the sensor board, so that the measuring side of the sensor board is not enclosed by the injection mold .

[0042] In particular, the layer thickness of the injection-molded material in the area of ​​the sensor board edge is at least 0.125 mm. Preferably, the layer thickness of the injection-molded material is in the range of 0.125 mm to 0.8 mm. This creates a sealing lip between the sensor board and the front cap as soon as the front cap is slid over the sensor board. This sealing lip prevents the ingress of dust, chemicals, and moisture.

[0043] According to a further development of the invention, a grounding element can be provided between the circuit board and the housing at a circuit board-side end of the connector housing (DTS: 40033. TUR. P110PC). The grounding element is preferably made of metal. However, any other electrically conductive material can also be used. The housing is preferably also made of an electrically conductive material, e.g., metal.

[0044] The grounding element can be formed by a metal ring that has at least one solder lug for contacting a ground pad on the circuit board, which in turn is connected to a capacitor on the circuit board. Additionally, the metal ring can have at least one protruding press-fit lug that establishes an electrically conductive contact with the housing. Specifically, exactly two solder lugs are provided, which hold the circuit board between them. It is advantageous if four press-fit lugs are also provided on the metal ring. The press-fit lug is, for example, a local radial widening of the ring.

[0045] The injection mold can be designed to allow the electrically conductive output, particularly in the form of a connector, to be fixed to the circuit board. Fixing the connector to the circuit board via the injection mold provides strain and pressure relief for the solder joints located between the connector and the circuit board.

[0046] According to a further development of the invention, the injection mold can additionally have one or more radially circumferential annular projections which function as sealing lips once the electronic component, as defined in the present invention, is inserted into a housing. These are preferably located in the connection area of ​​the connector and / or in the transition area of ​​the front cap to the injection mold. The radially circumferential sealing lips are preferably designed such that one or more of the sealing lips have an excess compared to the projections extending longitudinally along the injection mold. This excess enables a centering effect of the electronic component within a housing.Simultaneously, the excess of one or more of the radially circumferential sealing lips ensures that the force-fit connection occurs via the sealing lips, and consequently, no force-fit connection is formed between the preferably longitudinally extending protrusions on the injection mold and the inner surface of the housing. This further reduces the pressure on the electronic components caused by temperature fluctuations.

[0047] According to a further development of the invention, one or more sealing lips can be surrounded by an elastomeric material, such as a polyethylene (PE) or polypropylene (PP) foam film or a polyurethane flexible foam. At high temperatures, the injection-molded part expands more than the housing material, creating a back pressure that can lead to deformation of the sealing lip. This is particularly the case when the housing is a DTS: 40033. TUR. P110PC

[0048] The housing is made of metal. To counteract this, an elastomeric material is introduced in the area of ​​the sealing lips, which is easier to deform under the influence of temperature and thus compensates for the different coefficients of thermal expansion of the materials.

[0049] In an alternative embodiment of the invention, the injection mold can have one or more radially circumferential annular depressions. These radially circumferential depressions form one or more grooves. In a further development of the invention, one or more grooves can be lined with elastomeric sealing rings, thereby providing additional protection against dirt and moisture.

[0050] The electronic component described above in very general terms can be used, for example, to manufacture a proximity switch or any other electronic sensor. Other sensor types include: inductive sensor, capacitive sensor, pressure sensor, gas sensor, temperature sensor, humidity sensor, ultrasonic sensor, vibration detection sensor, and UV sensor. The aforementioned sensors constitute an electronic component, which in turn forms an electronic assembly as defined in the invention.

[0051] The present invention therefore also relates to an electronic component with a housing, in particular in the form of an electronic sensor, wherein the housing accommodates an electronic component according to the invention, characterized in that the injection mold rests forcefully against the inner wall of the housing via protrusions on its outer surface and simultaneously forms buffer areas between the injection mold and the inner wall of the housing.

[0052] The electronic component comprises a housing, the electronic assembly according to the invention, and optionally a front cap. The housing can be cylindrical and, in particular, tubular. Any other housing shape is also possible. The housing typically extends axially along a direction from a front to a rear. From the rear to the front, the housing successively accommodates the electrically conductive output, the electronic circuit board, and the sensor board in the form of the assembly according to the invention, as well as optionally the front cap.

[0053] In a preferred embodiment, the sum of all buffer zones within the housing constitutes a volume percentage of 5 to 45 vol%, particularly 15 to 40 vol%, based on the total internal volume of the housing. The term "buffer zone" as used in the present invention describes air-filled zones within the housing located between the inner wall of the housing and the outer circumference of the injection mold. DTS: 40033. TUR. P110PC

[0054] Furthermore, a method for embedding and protecting electronic components, in particular electronic sensors, from environmental influences is described. The electronic component can be one of the previously mentioned electronic components.

[0055] The process features specified below for the process may also be provided in device form in the electronic assembly and / or the electronic component.

[0056] In this process, an electrically conductive connection is first established between a sensor board and an electronic circuit board, as well as between the electronic circuit board and an electrically conductive output, particularly in the form of a connector or cable. This creates an assembled electronic component. After overmolding, this component can be inserted into the housing as a whole from the front.

[0057] In the next step, the assembled electronic component is placed in a mold and the electronic component is overmolded in a low-pressure injection molding process with a composition containing at least one thermoplastic material that can be processed by low-pressure injection molding, by placing the composition into the mold.

[0058] The injection mold is opened and the resulting injection-molded part, which surrounds the electronic component at least along the circuit board, can be removed from the injection mold.

[0059] In the final step of the process, the injection mold is inserted into the housing. The injection mold is designed in relation to the housing such that its outer surface has raised areas that allow for at least partial frictional contact between the injection mold and the inner surface of the housing, while simultaneously creating buffer zones between the injection mold and the inner surface of the housing. All of the aforementioned embodiments apply with regard to the design of the injection mold.

[0060] The process according to the invention is characterized in that a composition is used for the production of the injection mold which has a thermal conductivity of at least 0.2 W / m*K measured according to ISO 22007-2 (2022 edition). Otherwise, the above descriptions apply to the composition used in the process according to the invention.

[0061] In a further development of the inventive method, a front cap is placed over the sensor board before the electronic component surrounded by the injection mold is inserted into the housing. The front cap can also be subsequently placed over the sensor board DTS: 40033. TUR. P110PC after the electronic component surrounded by the injection mold has been inserted into the housing.

[0062] The procedure described above can be automated, and the individual steps are not performed manually.

[0063] Further advantageous embodiments are discussed with reference to the embodiment described below in conjunction with the figures.

[0064] This shows:

[0065] Fig. 1 shows an exploded view of an embodiment of an electronic component according to the invention in its assembly direction, in which the individual parts are joined together;

[0066] Fig. 2 shows a side view of a design of an injection molding body surrounding the electronic circuit board.

[0067] Fig. 3 shows an oblique view of an injection mold surrounding the electronics board and sensor board;

[0068] Fig. 4 shows a cross-sectional view of an electronic component;

[0069] Fig. 5a shows an oblique view of an embodiment of the injection molding bodies surrounding the electronic circuit board and sensor board;

[0070] Fig. 5b shows an oblique view of the embodiment of the injection body according to Figure 5a including the front cap;

[0071] Fig. 6 shows a cross-sectional view of an embodiment of an electronic component;

[0072] Fig. 7 shows an oblique exploded view of an electronic component in front of a contour-defining injection mold;

[0073] Fig. 8 Side view of a section of an embodiment of the electronic component in which a sealing lip is additionally surrounded by an elastomeric material;

[0074] Fig. 9 shows a side view of an alternative embodiment of the electronic assembly with a groove in the injection mold and an integrated sealing ring.

[0075] Fig. 1 shows an embodiment of an electronic component in its assembly direction, in which the individual parts are joined together. Fig. 1 shows a housing with reference numeral 100. In this case, it is cylindrical, namely tubular. DTS: 40033. TUR. P110PC

[0076] Housing 100 thus has an axial direction. Housing 100 has a front opening 101 on its front side.

[0077] The housing 100 also has a rear opening 102 on the back, the cross-section of which is smaller than the front opening 101. The housing 100 has a cylindrical inner circumferential surface 103.

[0078] The connector 105, the electronic circuit board 106 and the sensor board 107 can be connected to each other by soldering, for example in this case by selective soldering.

[0079] After contacting the rear ends of pins 113 of connector 105 with a first end of the electronics board 106 and contacting the contacts of the sensor board

[0080] The electronic circuit board 106, the sensor board 107, and the connector 105 form an electronic assembly 111 by connecting the sensor board 107, the electronic circuit board 106, and the connector 105 to corresponding contacts at a second end of the electronic circuit board 106. The contacting creates an electrically conductive connection between the sensor board 107, the electronic circuit board 106, and the connector 105.

[0081] The electronic circuit board 106 is surrounded by an injection-molded body 108 made of thermoplastic material. In the illustrated embodiment, the contour of the injection-molded body is formed as a rectangular polygon with concavely curved polygon lines and encases the electronic circuit board 106. In cross-section along the electronic circuit board 106, the injection-molded body 108 has a cross-shaped configuration.

[0082] The injection mold 108 is manufactured using a low-pressure injection molding process.

[0083] To manufacture an electronic component, the electronic assembly 111 is inserted into the housing 100. The protrusions 112 on the outer circumferential surface of the injection mold enable a force-fit connection between the injection mold 108 and the inner circumferential surface of the housing 103. At the same time, gaps 109 (not shown in Figure 1, see Figure 4) are created between the injection mold 108 and the inner circumferential surface of the housing 103, which act as buffer zones for thermal expansion.

[0084] The front cap 104 can be plugged over the sensor board 107 before the injection molding body

[0085] The electronic component 111, surrounded by 108, is placed into the housing 108.

[0086] Figure 2 shows a side view of the cross-shaped design of the injection mold 108 along the electronic circuit board 106. The cross-shaped injection mold is shown at a 1 / 20th of its size and illustrates how the electronic circuit board 106 is embedded within the injection mold 108. In the illustrated embodiment, the electrically conductive outlet is designed as a simple cable outlet 105a, which is electrically connected to the electronic circuit board 106. DTS: 40033. TUR. P110PC

[0087] Figure 3 shows an oblique view of an injection-molded body 108 surrounding the electronic circuit board 106 and the parts of the sensor circuit board 107 (both not shown). The electrically conductive outlet, which is preferably designed in the form of a connector 105 or a cable outlet 105a, is not shown. The injection-molded body 108 surrounds the electronic circuit board 106, the contact side of the sensor circuit board 116, and the sensor circuit board edge 115. In the illustrated embodiment, the measuring side of the sensor circuit board 117 is not surrounded by the injection-molded body 108.

[0088] The injection mold 108 has a cross-shaped design. Additionally, the injection mold 108 has two radially circumferential annular projections which function as sealing lips 118 when the electronic component is inserted into a housing. In the illustrated embodiment, the sealing lips are located in the connection area of ​​the connector and in the transition area of ​​the front cap 104 (not shown) to the injection mold 108.

[0089] Figure 4 shows a cross-sectional view of an electronic component 122 in the area and along the circuit board 106. The circuit board 106 is surrounded by a cross-shaped injection mold 108. The legs of the cross form strip-shaped protrusions 112 on the outer surface of the injection mold 108. In the illustrated embodiment, a force-fit connection between the injection mold 108 and the housing is achieved via radially circumferential sealing lips (not shown), which have an excess of thickness compared to the strip-shaped protrusions 112. There is no force-fit connection between the strip-shaped protrusions 112 and the inner wall of the housing. The cross-shaped geometry of the injection mold 108 allows for the formation of buffer areas 109 between the injection mold 108 and the inner circumferential surface of the housing 103.In an alternative embodiment, it is also possible that a force-fit connection exists between the protrusions 112 and the inner wall of the housing 103.

[0090] Figures 5a and 5b show oblique views of an embodiment of an electronic assembly 111, in which the electronic circuit board 106 (not visible) and sensor board 107 are surrounded by a cross-shaped injection-molded body 108. The injection-molded body 108 is designed to allow the connector 105 to be fixed to the electronic circuit board 106, thereby providing tensile and compressive stress relief for the solder joints (not shown) between the connector 105 and the electronic circuit board 106.

[0091] The injection mold 108 surrounds the electronic circuit board 106 as well as the contacting side of the sensor board 116 and the sensor board edge 115.

[0092] The injection mold 108 has two sealing lips 118 radially circumferential around the injection mold 108 in the connection area of ​​the connector 105 and in the transition area of ​​the front cap 104 to the injection mold 108. DTS: 40033. TUR. P110PC

[0093] Figure 5b shows the same embodiment of the electronic component as Figure 5a. Additionally, a front cap 104 is placed over the sensor board 107 (not visible). One of the sealing lips 118 is designed such that it lies in the transition area between the front cap 104 and the injection-molded body 108.

[0094] Figure 6 shows a cross-sectional view of an embodiment of an electronic component 122.

[0095] The housing 100 has an internal cylindrical circumferential surface 103. The housing 100 successively accommodates the connector 105, the electronic circuit board 106, the sensor circuit board 107, and the front cap 104 from the front opening of the housing 101. The electronic circuit board 106 and the sensor circuit board 107 are surrounded by a cross-shaped injection-molded body 108.

[0096] The injection molding body 108 has two sealing lips 118 radially circumferentially surrounding the injection molding body 108 in the connection area of ​​the connector 105 and in the transition area of ​​the front cap 104 onto the injection molding body 108. The sealing lips 118 have a slight oversize compared to the protrusions 112 on the injection molding body 108. The force-fit connection between the inner housing wall 103 and the injection molding body 108 is thus ensured in the area of ​​the sealing lips 118.

[0097] Figure 7 shows an oblique exploded view of an electronic assembly 111 in front of a contour-defining injection mold 121.

[0098] To manufacture the electronic assembly 111, a pre-assembled electronic assembly consisting of sensor board 107, electronic circuit board 106, and connector 105 is placed in a mold. The electronic assembly is then overmolded in a low-pressure injection molding process with a composition containing at least one thermoplastic material processable by low-pressure injection molding, by introducing the composition into the mold 121.

[0099] The mold can then be opened and the resulting injection-molded part, which surrounds the electronic component at least along the circuit board, can be removed from the mold 121.

[0100] Figure 8 shows a side view of a section of an embodiment of the electronic component, in which the sealing lip 118 in the connection area between the front cap 104 (not shown) and the injection mold is completely surrounded radially by an elastomeric material 123. The elastomeric material 123 can consist of a polyethylene (PE) or polypropylene (PP) foam film or a polyurethane flexible foam. DTS: 40033. TUR. P110PC

[0101] Figure 9 shows a side view of an alternative embodiment of the invention. The contour of the injection-molded shell 108 is designed such that a groove 119 is formed in the connection area of ​​the front cap 104, which receives a sealing ring 120. The sealing ring can be made of an elastomeric material.

[0102] DTS: 40033. TUR. P110PC

[0103] Reference symbol

[0104] 100 cases

[0105] 101 Front opening

[0106] 102 Back opening

[0107] 103 Inner circumferential area of ​​the housing

[0108] 104 Front cap

[0109] 105 plugs

[0110] 105a Cable outlet

[0111] 106 Electronic circuit board

[0112] 107 Sensor board

[0113] 108 injection molds

[0114] 108a Outer circumferential surface or shell surface of the spray body

[0115] 109 Buffer area or free spaces

[0116] 110 connector housings

[0117] 111 Electronic component

[0118] 112 surveys

[0119] 113 Pin

[0120] 114 Earthing element

[0121] 115 Sensor board edge

[0122] 116 Contact side of the sensor board

[0123] 117 Measuring side of the sensor board

[0124] 118 Sealing lip

[0125] 119 Nut

[0126] 120 sealing rings

[0127] 121 shaping injection mold

[0128] 122 Electronic component

[0129] 123 Elastomers Material

Claims

DTS: 40033. TUR. P110PC Patent claims 1. Electronic assembly (111) for manufacturing a sensor comprising at least one electrically conductive outlet (105), an electronic circuit board (106) and a sensor circuit board (107), wherein the electronic circuit board (106) and the sensor circuit board (107) as well as the electronic circuit board (106) and the electrically conductive outlet are each electrically conductively connected to one another, wherein the electronic assembly is completely surrounded at least along the electronic circuit board (106) by an injection-molded body (108), and wherein the injection-molded body (108) has projections (112) on its outer circumferential surface which enable at least a partially force-fit connection of the injection-molded body (108) to an inner circumferential surface of a housing (103) and simultaneously enable buffer areas (109) between the injection-molded body (108) and the inner circumferential surface of the housing (103) as soon as the electronic assembly is inserted into a housing (100), characterized in thatthat the injection molded part (108) is made from a composition comprising at least one thermoplastic material processable by low-pressure injection molding and having a thermal conductivity of at least 0.2 W / m*K as measured according to ISO 22007-2.

2. Electronic component (111) according to claim 1 , characterized in that the protrusions (112) on the outer circumferential surface of the injection body (108) are designed as strip-shaped protrusions (112) which extend in the longitudinal direction on the outer circumferential surface of the injection body (108).

3. Electronic component (111) according to claim 2, characterized in that the cross-sectional area of ​​the injection mold (108) has a polygonal shape, wherein the polygon lines are preferably concavely curved.

4. Electronic component (111) according to one of the preceding claims, characterized in that the thermoplastic material processable by low-pressure injection molding is selected from the group consisting of polyamides, polyesters, polyolefins, polyurethanes and mixtures thereof.

5. Electronic component (111) according to one of the preceding claims, characterized in that the composition for producing the injection mold (108) comprises at least one thermally conductive filler.

6. Electronic component (111) according to one of the preceding claims, characterized in that the injection molding body (108) is produced by means of a low-pressure injection molding process. DTS: 40033. TUR. P110PC is manufactured using a low-pressure injection molding process with a temperature range of 80 to 250 °C and an injection pressure of 3 to 60 bar.

7. Electronic assembly (111) according to one of the preceding claims, characterized in that the injection mold (108) also encases at least in part the sensor board (107), in particular wherein the injection mold (108) surrounds the side of the sensor board (107) facing the electronic board and the sensor board edge (115).

8. Electronic assembly (111) according to one of the preceding claims, characterized in that the injection body (108) has one or more sealing lips (118) that completely circumferentially surround the injection body radially.

9. Electronic component (111) according to claim 8, characterized in that one or more sealing lips (118) are surrounded by an elastomeric material (123).

10. Electronic component (122) with a housing (100) which has an inner housing wall (103), wherein the housing (100) accommodates an electronic component (111) according to one of claims 1 to 9, characterized in that the injection molding body (108) bears against the inner housing wall via protrusions (112) on its outer surface in a force-fit manner and buffer areas (109) are formed between the injection molding body (108) and the inner housing wall (103).

11. Electronic component (122) according to claim 10, characterized in that the sum of all buffer areas (1109) within the housing (100) occupies a volume percentage of 5 to 45 vol-% of the total volume of the housing.

12. Electronic component (122) according to one of claims 10 or 11, characterized in that the electronic component (122) is a sensor type selected from the group consisting of proximity switches, inductive sensors, capacitive sensors, pressure sensors, gas sensors, temperature sensors, humidity sensors, ultrasonic sensors, vibration detection sensors or UV sensors.

13. Method for embedding and protecting electronic components, in particular electronic sensors, from environmental influences, comprising the steps of: a. Establishing an electrically conductive connection between a sensor board (107) and an electronics board (106) and the electronics board (106) and DTS: 40033. TUR. P110PC a electrically conductive outlet (105, 105a) for the manufacture of an electronic component; b. Insertion of the electronic component into a mold (121); c. Overmolding of the electronic component (111) with a composition containing at least one thermoplastic material processable by low-pressure injection molding; d. Removal of the injection-molded component (108) from the mold (121); e.Insertion of the injection molding body (108) into a housing (100), wherein the injection molding body (108) is designed in relation to the inner circumferential surface of the housing (103) such that the injection molding body (108) has protrusions on its outer surface which enable at least a partially force-fit connection of the injection molding body (108) to the inner surface of the housing (103) and at the same time enable the formation of free spaces (109) between the injection molding body (108) and the inner surface of the housing (103), characterized in that the composition has a thermal conductivity of at least 0.2 W / m*K measured according to ISO 22007-2 (2022).

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