Housing part

Abstract

Housing part (10) for a housing (7) of a traction battery (6) of an electrically powered motor vehicle (1), with at least one wall (32) made of plastic, wherein at least one chamber (30, 31) for receiving one or more insert parts is formed in the wall (32), characterized in that the wall (32) is produced by a fused deposition process, and that a film (12) protecting against electromagnetic radiation and / or at least one sensor (13) are inserted into the respective chamber (30, 31) as an insert part, wherein the film (12) and / or the sensor (13) can be electrically contacted by means of electrical conductors (27, 28) integrated into the wall (32).

Description

[0001] The invention relates to a housing part, in particular for a housing of a traction battery of an electrically powered motor vehicle, with a wall made of plastic, wherein at least one chamber, in particular a closed chamber, is formed in the wall for receiving one or more insert parts.

[0002] Furthermore, the invention relates to a method for manufacturing such a housing part.

[0003] With the increasing electrification of motor vehicles, the demands on electrical energy storage systems are also rising. In vehicles that can be electrically powered, such as hybrid vehicles with a combustion engine and an electric motor, or in electric vehicles that can only be powered electrically, the drive energy is drawn from an electrical energy storage system that must be integrated into the vehicle. These energy storage systems are often integrated into the vehicle's underbody structure, located beneath a rear row of seats. This integrated design reduces the overall mass of the component, which has a positive effect on the vehicle's achievable range.

[0004] Such a housing component is known, for example, from German patent application DE 10 2011 052 515 A1. This housing component is at least partially made of a thermoplastic or thermosetting plastic material, which offers cost advantages compared to conventionally manufactured aluminum housing components. A disadvantage of using plastic housing components is that they offer reduced protection against electromagnetic radiation compared to conventional battery housings. It is particularly important to minimize the electromagnetic radiation that can enter the vehicle interior and to prevent the operation of the energy storage system from being impaired by external electromagnetic radiation.Therefore, the aforementioned patent application provides for the additional inclusion of a planar element on the housing component to shield the traction battery from electromagnetic radiation. This planar element could, for example, be a metal foil or a metallic mesh. For integration into the wall, it is at least partially embedded within the wall.

[0005] From the patent application DE 10 2011 077 187 A1, a shield for a traction battery of a motor vehicle is known, which consists of two semi-finished products, each having a film made of an electrically insulating material and connected to each other.

[0006] Furthermore, a housing component with a plastic wall, comprising at least one cavity, is known from German patent application DE 10 2011 052 513 A1. A thermal insulation material is inserted into this cavity, which forms a chamber. To manufacture the housing component, fiber-reinforced mats with a thermoplastic matrix are provided. The insulation material is placed on a first mat, and then a second mat is placed on top of the first mat and the insulation material. The two mats are then heated, fused together, and plastically deformed to achieve the shape of the housing component.

[0007] Furthermore, German patent application DE 10 2015 224 777 A1 discloses a battery housing component that can be manufactured using a 3D printing process, wherein the battery housing is built up layer by layer from a molten metal or plastic material.

[0008] The invention is based on the objective of creating an improved housing component that ensures an advantageous electromagnetic shielding effect and is cost-effective and structurally simple to manufacture, even if the housing component itself is to have a complex three-dimensional shape.

[0009] The problem underlying the invention is solved by a housing part with the features of claim 1 and by a method with the features of claim 10. The housing part and the method according to the invention have the advantage that the wall is manufactured in a simple manner, and that the wall is not limited to a specific shape, but rather different wall shapes can be produced successively with the same device / tool, even in mass production, without the need for tool changes. Furthermore, the housing part offers improved electromagnetic shielding and the possibility of simple and cost-effective integration of one or more sensors into the housing part itself.

[0010] The invention provides that the wall is manufactured using a fused deposition modeling (FDM) process, and that a film protecting against electromagnetic radiation and / or at least one sensor are inserted into the respective chamber as an insert. A fused deposition modeling process is an additive manufacturing process also known as FDM.

[0011] This process is characterized by the fact that a component is manufactured by melting, extruding, and depositing plastic layer by layer using a heated and movable nozzle. In this respect, the fused deposition modeling (FDM) process corresponds to a 3D printing process in which molten plastic is used as the printing medium. The nozzle that extrudes the material is equipped with a drive, in particular a linear drive, so that it can move in three-dimensional space to give the component any desired shape. After a layer of material is deposited, the nozzle is moved upwards or a build platform supporting the material is moved downwards, and the next layer is deposited through the nozzle.This layer-by-layer deposition of the plastic allows for almost unlimited design freedom, as the shaping process is not limited by the demolding process required for die casting. Furthermore, the fused deposition modeling (FDM) process readily enables the creation of one or more chambers, which can be positioned at any desired location. During the FDM process, specifically during the printing phase, the film and / or sensor is inserted into the still-unfinished chamber. The printing process then continues to close, or at least partially close, the chamber, thus enclosing the film and / or sensor. This ensures simple, cost-effective, and advantageous integration of the film and / or sensor into a specific chamber.

[0012] According to a preferred embodiment of the invention, the film is designed as an EMC shielding film (EMC = electromagnetic compatibility). EMC shielding films are commercially available films specifically manufactured for shielding electromagnetic fields. This makes the electromagnetic shielding of the housing component cost-effective by using existing films.

[0013] Preferably, several chambers are formed in the wall of the housing part, each containing an EMC foil and / or a sensor. This allows, for example, the integration of an EMC foil for electromagnetic shielding on the one hand and one or more sensors for monitoring the traction battery on the other.

[0014] According to the invention, the film, in particular EMC film, and / or the sensor are electrically contactable from the outside via electrical conductors integrated into the wall. The fused deposition modeling process makes it possible to easily integrate electrical conductors into the wall during its manufacture. Due to the integrated design of the conductors, they are reliably protected from external influences and provide a secure electrical connection for the sensors and / or films located in the chamber. Furthermore, the advantageous printing process allows the conductors to be guided through the wall in any desired configuration, for example, to meet the connection requirements of different customers.

[0015] Preferably, at least one of the electrical conductors is designed as a conductor printed from electrically conductive paste. In this case, not only is the plastic wall produced by a 3D printing process, but the conductor is also produced by a printing process, in particular a dispersion process, using a nozzle that dispenses the printing paste. This allows for the simple production of different wall thicknesses and / or electrical conductors without requiring any modifications to the printing machine producing the component.

[0016] Preferably, at least one of the chambers has one or more retaining projections spaced apart from a chamber side edge. This means that at least one of the chambers contains at least one retaining projection which, for example, divides or partially penetrates the chamber, thereby acting as a positive-locking retaining element for a film and / or a sensor positioned in the chamber. The one or more retaining projections also make it possible, for example, to securely position a film and a sensor in the same chamber.

[0017] Furthermore, it is preferably provided that the respective retaining projection is designed as a retaining rib or as a retaining bolt. If the retaining bolt preferably has a circular cross-section, the retaining rib is characterized by a longitudinal extent that is greater than its width, whereby the retaining rib, unlike the retaining bolt, also offers the advantage of, for example, anti-rotation protection.

[0018] The film preferably has one or more recesses corresponding to the retaining projections. For example, if a retaining projection is formed in the chamber, the film associated with this chamber advantageously has a recess that corresponds to the retaining projection in such a way that the film can be inserted into the chamber such that the retaining projection penetrates the recess or at least engages with it. This ensures secure positioning and alignment of the film in the chamber by means of the retaining projection, even if the film has smaller dimensions than the interior of the chamber. The same applies to a sensor positioned in the chamber, which preferably has one or more recesses on a housing part corresponding to the retaining projections to enable secure positioning of the sensor in the chamber.

[0019] Furthermore, preferably at least one support element is integrated into the wall to increase its mechanical strength and / or to weight the film within the chamber. The support element is, for example, a metal component that is positioned between two layers during the fused deposition modeling (FDM) process, or positioned on top of a layer before a second layer is applied. The support element increases the mechanical strength of the wall in a simple manner. The support element can be, for example, a support rod, a support strip, and / or a support tray integrated into the wall.

[0020] Preferably, the housing part is designed as a battery housing cover. For this purpose, the housing part has connecting means for attaching the battery housing cover to a receiving body for the traction battery, in order to close the receiving body and enclose or protect the traction battery within it. For this purpose, the battery housing cover has, for example, an outer contour that corresponds to the outer contour of the receiving body, which is designed, in particular, as a housing tray. Furthermore, the battery housing cover preferably has one or more projections that can be inserted into corresponding recesses in the receiving body to facilitate and permanently ensure the alignment and positioning of the battery housing cover on the receiving body.Optionally, the battery housing cover also has at least one circumferential molded or attached sealing lip that interacts with the receiving body to ensure a media-tight connection between the battery housing cover and the receiving body.

[0021] The inventive method with the features of claim 10 provides that, by means of a fused deposition modeling process using a movable nozzle, in a first step a) at least one planar base layer of the wall is printed, in a subsequent step b) at least one chamber layer is printed onto the base layer, which has one or more recesses for forming a chamber, wherein in a subsequent step c) a sensor and / or a film protecting against electromagnetic radiation is inserted into at least one of the recesses, and that in a subsequent step d) a cover layer of the wall covering the one or more recesses is printed or applied onto the chamber layer. This results in the advantages already mentioned. Further advantages and preferred features and combinations of features also result from the foregoing and from the claims.

[0022] In particular, it is provided that at least one electrically conductive conductor track is printed onto the chamber layer for electrical contacting of the sensor and / or the film immediately before or immediately after step c). Specifically, an electrically conductive conductor paste is applied or printed onto the chamber layer and / or the base layer, preferably using a dispersion device, to print the conductor track. This results, as mentioned above, in an advantageous and simple electrical contact integrated into the wall. Furthermore, it is preferably provided that at least one of the sensors is inserted into the recess with a protective housing. This recess leaves a mechanical contact surface of the sensor exposed but protects the electrical contact surfaces, so that in a subsequent plastic printing process, only the mechanical contact surface is printed initially.The sensor's protective housing is then removed and electrical contact is established by printing an electrically conductive paste using the dispersion process described above.

[0023] The invention will now be explained in more detail with reference to the drawing. To this end, we show Fig. 1. A simplified sectional view of the arrangement of a traction battery in a motor vehicle, Fig. 2 a device for manufacturing a housing part, Fig. 3 the step-by-step production of the housing part using the device made of Fig. 2, Fig. 4A and Fig. 4B an advantageous embodiment of the housing part in different views and Fig. 5A and Fig. 5B shows another advantageous embodiment of the housing part in different views.

[0024] Fig. Figure 1 shows a simplified side view of the interior of a motor vehicle 1 in the area of ​​a rear seat row 2. The seat row 2 has at least one seat that is movable along a longitudinal guide 3, as indicated by a double arrow 4. A cavity 5 is created below the longitudinal guide for accommodating a traction battery 6, which is connected or connectable to an electric drive of the motor vehicle, thus enabling electric motor operation of the motor vehicle. The traction battery 6 is arranged in a protective housing 7, which has a trough-shaped receiving body 8 and a battery housing cover 9 that closes the receiving body 8 at the top. The battery housing cover 9 thus constitutes a housing part 10 for the traction battery 6 or the protective housing 7.

[0025] The housing part 10 has a base body 11 made of plastic in which, according to the present embodiment, several films 12 are arranged that protect against electromagnetic radiation, as well as a sensor 13 designed to monitor the traction battery 6. For this purpose, the sensor 13 is designed, for example, as a temperature sensor that monitors the operating temperature of the traction battery 6.

[0026] With reference to Fig. 2 and Fig. Section 3 below will explain the basic structure of the housing part 10 and its manufacture.

[0027] Fig. Figure 2 shows a simplified representation of a device 11 for manufacturing the housing part 10. The device 11 has a nozzle 14 which includes a controllable heater, and a plastic material 15 in the form of a plastic filament is fed to the nozzle. The nozzle 14 is movable in a plane parallel to a printing table 17 located below the nozzle 14 by means of a bearing device 16, as indicated by a double arrow, and is also adjustable in height, i.e., perpendicular to the printing table 17, as indicated by a further double arrow 18. Alternatively or additionally, the printing table 17 itself is movable in height.

[0028] By heating the nozzle 14, the plastic material is melted and applied in a controlled strip pattern to the printing plate 17 through the nozzle 14. This process creates a layer by applying several adjacent strips, and complexly designed or shaped components are produced using the fused deposition modeling (FDM) process by applying multiple layers. Fig. Figure 2 shows an example of such a component 19 with a printed support structure 20. Component 19 could, for example, be the housing part 10. Once a layer is printed, the nozzle 14 is moved upwards and / or the print bed 17 is moved downwards so that the next layer can be applied.

[0029] Fig. Figure 3 shows in several steps a) to e) the production of the housing part 10 using the device 11 in a simplified manner.

[0030] In the first step a), two base layers 21 are applied to the printing table 17 using the nozzle 14.

[0031] In a subsequent step b), two chamber layers 22 are applied, which differ from the base layers 21 in that they have several recesses 23, 24. The recesses 23, 24 do not necessarily have to be present in both chamber layers 22, but can, as in Fig. Figure 3, with reference to the recess 24, shows that it may also exist in only one chamber layer. For example, one recess may extend over only one chamber layer and another recess over several chamber layers, as shown in Figure 3. Fig. 3 shown. Of course, a recess 23, 24 can also extend over more than two chamber layers.

[0032] In the following step c), the sensor 13 is inserted into the recess 23, which extends over several chamber layers 22, and one of the films 12 is inserted into the other recess 24.

[0033] In the next step, electrical conductors are formed. For this purpose, the device 11 has a dispersion unit 25, which can be moved, for example, by means of the bearing 16 or by means of its own bearing above the printing table 17 in three-dimensional space. The dispersion unit 20 has a dispersion nozzle 26, by means of which electrically conductive paste can be applied to the printing table 17 and / or the plastic already applied there.

[0034] Because the dispersion nozzle 26 is also freely movable, it is possible to selectively apply the conductor tracks to the existing plastic layers and / or sensors or films, even in three dimensions. Fig. Figure 3 shows in step d) two conductive traces 27 and 28, which are applied to the uppermost chamber layer in such a way that they electrically contact the sensor 13 and the film 12. Advantageously, the conductive traces terminate externally at the housing part 10, so that simple electrical contact between the sensors 14 and / or films 12 is ensured.

[0035] Subsequently, at least one, and advantageously several, cover layers 29 are applied to the chamber layer 22 and the sensors or films inserted into the recesses 23, 24 using the nozzle 14, so that the recesses 23 and 24 are closed and formed into closed chambers 30, 31 in which a sensor and / or a film 12 are arranged.

[0036] The advantageous integration of the dispersion process into the fused deposition modeling process facilitates the electrical contacting of the electrical components in the housing part 11. The applied layers 21, 22, and 23, as well as the components integrated therein, such as sensor 13, film 12, and conductive traces 27 and 28, together form an advantageous wall 32 of the housing part 10, which in particular forms the entire battery housing cover 9. Thanks to the advantageous manufacturing process and the design of the housing part 10, even complex three-dimensional shapes of the battery housing cover 9 can be realized cost-effectively. This also allows for easy adaptation to different customer requirements.

[0037] The battery housing cover 9 is advantageously shaped such that it can subsequently be placed on the receiving body 8 and thus glued and / or screwed in place. Heat bonding and / or the provision of a seal are also possible. A plastic that is as strong and rigid as possible is preferably used to absorb the mechanical forces even in the event of an accident without damaging the protective housing 7. ABS, Nylon 6, Nylon 6.6, Nylon 12, or Nylon 12CF are preferably used as the plastic filament for the FDM process and are preferably equipped with flame retardant additives.

[0038] While sensor 13 has been described in the present case as a temperature sensor, it is also conceivable to provide a pressure sensor, humidity sensor, AFID chip for structural monitoring, or the like as an insert in one of the chambers of the wall 32. It is also conceivable to provide glass, carbon, and / or aramid fibers, particularly in the form of an organosheet or as a sheet-like semi-finished product, such as woven fabrics, non-woven fabrics, knitted fabrics, or the like, as an insert to locally increase the mechanical properties, particularly along the load-bearing phase of the battery housing cover 9, and to arrange them in one of the chambers. The inserts are preferably placed automatically into the corresponding recess during the manufacturing process of the wall 32 by a placement device, thus enabling fully automated production of the housing part.

[0039] Preferably, the respective film 12 has a roughened surface to ensure permanent adhesion to the plastic. To securely position the film 12 during the manufacturing process, in addition to a form-fitting position in the respective chamber 24, the film can also be fixed against slipping and / or twisting by means of additional retaining projections.

[0040] Fig. 4A and Fig. Figure 4B shows, in a simplified embodiment, an advantageous further development of the housing part 10. Fig. Figure 4A shows the production of the housing part 10, in which several retaining projections 33 are produced in one of the chambers 24 by dispensing plastic using the nozzle 14. The retaining projections 33 are thus formed together with the chamber layer 22 or with the chamber layers 22.

[0041] Fig. Figure 4B shows the manufacturing process in a top view of the housing part 10. It can be seen that the retaining projections 33 in the chamber 24 are arranged at intervals from the side edges 34 of the chamber 24. In this case, there are four retaining projections 33. Furthermore, this view also shows that, due to the advantageous manufacturing process, a strip-shaped structure of plastic results because the strips are applied successively.

[0042] The film to be inserted into chamber 24 expediently has recesses 35 corresponding to the retaining projections 33. In this case, the retaining projections 33 are designed as retaining ribs. Alternatively, retaining bolts with a circular cross-section could also be provided. The advantageous interaction of the film 12 with the retaining projections 33 reliably prevents the film from slipping within chamber 24 during manufacturing.

[0043] Fig. 5A and Fig. Figure 5B shows an alternative embodiment that differs from the preceding embodiment in that the retaining projections 33 are omitted, and instead a support element 36 is placed on the film 12 in the chamber 24. The support element 36 acts as a weighting element for the film 12, which is held in the chamber 24 by the support element 36. The support element also serves to increase the mechanical strength of the wall 33. Alternatively, the support element 36 is arranged in its own chamber in the wall 32, in particular spaced apart from the film 12 and / or the sensor 13 by at least one cover or base layer.

[0044] According to a further embodiment, the sensor 13 is inserted into a protective housing 7 before being placed inside, so that only one contact surface is coated with plastic. The protective housing 7 can then be removed, and the advantageous design of the housing part 10 allows for the flexible integration of a wide variety of sensors into the housing part 10 or the battery housing cover 9. This saves time and costs, particularly during the development phase of this component. However, the method is also applicable to high production volumes in mass manufacturing. By melting the plastic, the individual inserts are gently attached to or integrated into the housing part 10 with minimal pressure. The film 12 can also be electrically connected directly via a closed clamp or a bridge, which can be connected, for example, by a screw connection. Reference symbol list 1 motor vehicle 2nd row of seats 3 Longitudinal guidance 4 Double Arrow 5 Cavity 6 traction batteries 7 Protective housings 8 recording bodies 9 Battery case covers 10 Housing part 11 Base body / device 12 slides 13 Sensor 14 nozzle 15 plastic material 16 Storage facility 17 Printing table 18 Double Arrow 19 Component 20 Support structure 21 Base layer 22 chamber layer 23 recess 24 recesses 25 Dispersion unit 26 Dispersion nozzle 27 conductor track 28 conductor track 29 Top layer 30 chambers 31st Chamber 32 wall 33 Holding advantage 34 side margin 35 recess 36 support element

Claims

[1] Housing part (10) for a housing (7) of a traction battery (6) of an electrically powered motor vehicle (1), with at least one wall (32) made of plastic, wherein at least one chamber (30, 31) for receiving one or more insert parts is formed in the wall (32), characterized by , that the wall (32) is produced by a fused deposition process, and that a film (12) protecting against electromagnetic radiation and / or at least one sensor (13) is inserted into the respective chamber (30,31) as an insert, wherein the film (12) and / or the sensor (13) can be electrically contacted by means of electrical conductors (27,28) integrated into the wall (32). [2] Housing part according to claim 1, characterized by , that the film (12) is designed as an EMC protective film. [3] Housing part according to one of the preceding claims, characterized by, that several chambers (30,31) are formed in the wall (32), in each of which an EMC foil (12) and / or a sensor (13) is arranged. [4] Housing part according to one of the preceding claims, characterized by , that at least one electrical conductor (27,28) is designed as a conductor printed from electrically conductive paste. [5] Housing part according to any one of the preceding claims, characterized by , that in at least one of the chambers (30,31) one or more retaining projections (33) are formed spaced apart from a chamber side edge (34). [6] Housing part according to any one of the preceding claims, characterized by , that the respective retaining projection (33) is designed as a retaining rib or as a retaining bolt. [7] Housing part according to one of the preceding claims, characterized by that the foil (12) has one or more recesses (35) corresponding to the retaining projections (33). [8] Housing part according to one of the preceding claims, characterized by , that at least one support element (36) is integrated into the wall (32) to increase the mechanical strength of the wall (32). [9] Housing part according to any one of the preceding claims, characterized by the training as a battery casing cover (9). [10] Method for manufacturing a housing part (10), in particular according to one of claims 1 to 9, which has at least one wall (32) made of plastic, wherein at least one, in particular closed, chamber (30, 31) for receiving one or more insert parts is formed in the wall (32), comprising the following steps: a) By means of a fused deposition modeling process with a movable nozzle (14) printing at least one planar base layer (21) of the wall (32), b) Printing at least one chamber layer (22) which has one or more recesses (23, 24) to form a chamber (30, 31) c) Inserting a sensor (13) and / or a film (12) that protects against electromagnetic radiation into at least one of the chambers (30, 31), d) Printing a cover layer (29) of the wall (32) covering the recesses (23,24), wherein, prior to intermediate steps c) and d), at least one electrically conductive conductor track (27,28) is printed onto one of the chamber layers (22) for electrical contacting of the sensor (13) and / or the film (12).

Images