Casing for automotive applications

Abstract

The invention relates to a casing for automotive applications, in particular to a motor vehicle lock casing, and preferably to a motor vehicle door lock casing. This casing is equipped with an electric connection element (3) for peripherally contacting a conductor track structure (1) which is electrically and mechanically connected to the connection element (3) and has electric components (2, 4) arranged thereon in the casing interior, and this casing is equipped with a cover (6). A connection region (3a) of the connection element (3) is exposed in respect of the cover (6), which offers protection against environmental impacts, and thus accessible for the conductor track structure (1). According to the invention, the cover (6) and / or a casing base (5) have / has a receiving trough (9a, 9b) for potting compound, which receiving trough comprises the exposed connection region (3a).

Description

[0001] Description

[0002] Housings for automotive applications

[0003] The invention relates to a housing for automotive applications, in particular a motor vehicle lock housing, with an electrical connection element for peripherally contacting a conductor track structure that is electrically and mechanically connected to the connection element and has electrical components arranged thereon in the housing interior, and with a cover, wherein a connection region of the connection element is exposed with respect to the cover for the conductor track structure that protects against environmental influences.

[0004] Housings for automotive applications must meet a wide range of requirements. This applies, for example, to temperature resistance, which must generally cover a range from -50°C to +80°C or +100°C, or even higher, depending on the installation location and application. Nevertheless, such housings are usually made of plastic, particularly a thermoplastic such as polyethylene, polypropylene, polycarbonate, or polyamide. Embedded fibers, for example, made of glass or carbon, can also provide additional stabilization. In this case, the housing in question serves to protect the conductor track structure housed within it from environmental influences such as dust or moisture. The conductor track structure, in turn, serves to accommodate electrical components.

[0005] The term "electrical components" should be interpreted broadly in this context and includes, by way of example and not limitation, an electronic control unit, switches, capacitors, resistors, but also one or more electric drive motors, etc. These capacitors can be so-called supercapacitors, i.e., capacitors with particularly high capacitance that serve as an emergency power source, for example, for emergency unlocking or opening of a vehicle lock. As an alternative to the aforementioned supercapacitors, one or more accumulators or batteries can also be placed on the circuit structure at this point.

[0006] The conductor pattern itself is usually manufactured as a lead frame, for example, from a punched-out copper foil. After the conductor pattern has been manufactured and populated into the housing, it is usually completely or partially sealed with a potting compound. For this purpose, the potting compound is generally poured into the top-opening housing in a flowable state and hardens. This generally seals the conductor pattern and the components located on it, providing permanent protection against the environmental influences described.

[0007] For this purpose, the generic prior art according to DE 203 07 111 U1, for a component carrier, particularly in the form of a lock housing for a motor vehicle door lock, proceeds in such a way that the connecting element and the conductor track structure form a prefabricated unit. This unit is then inserted into the component carrier for assembly. This has generally proven successful, but still requires improvement in that individual or all of the connecting elements' connecting conductors are fully or partially exposed in the connection area. This exposed layout of individual connecting conductors can lead to them corroding or being otherwise exposed to environmental influences. In this case, there is even a fundamental possibility that a gradual short circuit could occur between individual connecting conductors, for example due to moisture.

[0008] Another prior art, also attributable to the applicant, according to DE 20 2008 015 696 U1, concerns a component carrier for essentially electrical components. These constitute a component of motor vehicle locking systems. In this context, a base and at least one side wall are implemented. The side wall is at least partially detachably connected to the base, thus providing a receptacle for the potting compound.

[0009] In fact, the consumption of potting compound is quite critical in terms of the associated costs. This means that in practice, the required volume of potting compound per correspondingly equipped enclosure is attempted to be kept as low as possible. For this reason, a cover is used that functions, or may function, as the enclosure lid and, like the enclosure base, is typically made of plastic. By using such a cover, the consumption of potting compound can essentially be reduced, as shown in DE 10 2015 109 494 A1. However, this does not change the aforementioned problems of any still exposed connecting conductors.

[0010] The invention is based on the technical problem of further developing a housing for automotive applications of the initially described design in such a way that the protection against possible environmental influences is further increased compared to the prior art.

[0011] To solve this technical problem, the invention proposes, starting from a generic housing for automotive applications, that the cover and / or a housing base has a receiving tray for casting compound that encompasses the exposed connection area.

[0012] According to the invention, the exposed connection area of ​​the connection element is therefore addressed in particular. This means that if individual or all of the connection conductors of the connection element are or have been at least partially exposed at this point up to now and in the prior art, a receiving tray provided in the cover, in the housing base, or in both components ensures that this exposed area of ​​the connection conductors is and can be sealed according to the invention. This is because at this point the cover and / or the housing base is equipped with a receiving tray which encompasses the exposed connection area, i.e. encloses it completely. This receiving tray then serves to allow potting compound to be poured into this point, which, after curing, protects the connection conductors accordingly from environmental influences.

[0013] This also allows for particularly economical use of the potting compound, because the expansion and topological design of the receiving tray is limited to the exposed connection area of ​​the connecting element. This reduces the amount of potting compound to the absolute minimum from the outset, according to the invention, while simultaneously providing optimal protection for the previously exposed connecting conductors of the connecting element. Furthermore, this reduces the required assembly time, because the small amount of potting compound required also reduces the process of filling the potting compound into the receiving tray to a minimum. This represents the key advantages.

[0014] According to a further advantageous embodiment, the cover preferably completely covers the conductor track structure and seals the conductor track structure from the housing base. This means that the cover not only ensures that the conductor track structure is mostly completely covered, but also seals the conductor track structure from the housing base. In this context, the cover can also function as a housing lid for the housing. For example, the housing base may have a trough-shaped or U-shaped cross-section, whereas the cover usually has a flat design. This is of course only an example. To intensify the sealing effect between the cover and the housing base, the cover is preferably placed on the housing base with a seal interposed. This creates a gap between the housing base and the cover.The intermediate space advantageously accommodates the conductor track structure including the electrical or electronic components located and contacted on it.

[0015] It has proven effective to design the seal as a separate element attached to the housing base and / or the cover. This can, for example, be an applied bead. Such a bead is typically applied in production using a nozzle or bead nozzle. A foam or adhesive, or both, exits a supply line or reservoir via this nozzle and can then be applied in a controlled manner along the desired contour to the housing base, the cover, or both.

[0016] Alternatively or additionally, it is also possible for the seal to form a structural unit manufactured together with the housing base and / or the cover. The invention is based on the knowledge that, as a rule, both the housing base and the cover are designed as plastic components and, in particular, as plastic injection-molded components. When manufacturing this plastic component by injection molding, the seal can be molded on from the outset, for example in a two-component injection molding process. Accordingly, the seal, together with the housing base or the cover, is advantageously a two-component injection-molded part. By way of example, the procedure is that the housing base is first manufactured by injection molding and then the seal is injection-molded onto this housing base, taking into account the required seal path and the necessary seal contour.This usually involves working with components of varying elasticity. While in this example a rigid thermoplastic such as polyamide, polyethylene or polypropylene or combinations is used for the housing base and cover, the seal is generally an elastomeric thermoplastic such as SBR (styrene butadiene rubber), NR (natural rubber), or EPDM (ethylene propylene rubber), to name just a few. Of course, the methods mentioned for designing and attaching the seal can also be combined, for example with the seal being designed as both a foam bead and as an injection-molded component. Generally, however, either one or the other method is used.

[0017] The receiving tray is preferably a rectangular tray with an upward opening that encloses all (exposed) connecting conductors of the connecting element and is open at the top. The potting compound can then be poured through the opening at the top. Once cured, it provides the desired seal for the previously exposed connecting conductors of the connecting element.

[0018] In this context, it has proven particularly advantageous and is of particular inventive significance to have the receiving tray constructed in two parts, essentially consisting of a cover part and a housing part. This means that the receiving tray is generally composed of two parts, the cover part and the housing part. The cover part is provided on the cover, while the housing part is a component of the housing base.

[0019] In fact, in this context, the usual approach is to connect the housing part to the cover part with the interconnected conductor structure interposed, preferably with the same contour. Furthermore, the design is additionally such that the cover part and the housing part, when installed, define the receiving trough, which is closed at the sides and bottom and open at the top.

[0020] This means that the mounting tray, which generally consists of the housing part and the cover part, accommodates the assembly and the usually interposed conductor track structure. This is usually done by molding the housing part to the tray base. Once the conductor track structure, with its electrical components and the electrically and mechanically connected connection element, is placed on or inserted into the housing base, the seal can be applied or provides the desired and subsequent closure when the cover is subsequently applied.

[0021] As already explained, the housing base is equipped with the housing part of the receptacle. Once the conductor track structure with the electrical components and the connected connector element is closed at the top using the cover, the seal located between the housing base and the cover ensures the desired protection of the space between them from any environmental influences. At the same time, the cover part and the housing part are aligned one above the other at this point. This is because the cover part and the housing part generally have the same contours when installed, so that when combined and in this installed state they define the receptacle, which is closed at the sides and bottom and open at the top.

[0022] The potting compound can then be poured into this receiving tray in a flowable state, where it then hardens. The side walls of the cover part and the housing part, both components of the receiving tray, prevent the potting compound from flowing into the space between the cover and the housing base. This minimizes the consumption of potting compound and actually reduces it to the critical area, namely the connecting conductors of the connecting element, which were previously exposed in the prior art. This represents the key advantages.

[0023] The invention is explained in more detail below with reference to a drawing which merely represents an exemplary embodiment; in the drawings:

[0024] Fig. 1 A to 1 D show the housing according to the invention for automotive applications in the form of a motor vehicle lock housing and specifically a motor vehicle door lock housing in different stages of production,

[0025] Fig. 2 shows a section through the housing according to Figures 1A to 1D in the installed state in the area of ​​the connecting element and

[0026] Fig. 3A and 3B show the area of ​​the connecting element from above, once without the potting compound filled (Fig. 3A) and the other with the potting compound filled (Fig. 3B).

[0027] The figures show a housing for automotive applications. The housing in question is, not only by way of limitation, a motor vehicle door lock housing. This means that the housing generally not only accommodates a conductor track structure 1, as shown in Fig. 1B, with electrical components 2, 4 located thereon. Rather, in addition to the conductor track structure 1 including the electrical components 2, 4, the motor vehicle door lock housing also contains the required locking mechanism of the motor vehicle door lock (not shown in detail). This can be a locking mechanism consisting essentially of a rotary latch and pawl, an operating lever chain, one or more electric drive units, etc. In principle, however, the housing shown does not necessarily have to be designed as a motor vehicle door lock housing.It could just as well be a drive housing for an electric motor drive (not shown) in a motor vehicle, a housing for accommodating an emergency electrical energy source, etc.

[0028] The basic structure of the housing consists of a housing base 5 and a cover 6. Furthermore, a seal 7 is provided between the housing base 5 and the cover 6, the location and contour of which can be seen in Fig. 1A.

[0029] The electrical components 2, 4 connected to the conductor track structure 1 are, in the context of the exemplary embodiment and merely by way of example, sensors or switches, in particular microswitches 2, an additional connection element 3, and finally one or more capacitors 4 or an emergency power source formed and defined thereby. This is, of course, only by way of example, because the conductor track structure 1 usually also accommodates and contacts resistors, a control unit, etc., which are not shown in detail.

[0030] In the exemplary embodiment, the conductor track structure 1 is an electrical punched grid, i.e., a flat structure punched out of copper foil or, more generally, metal foil, consisting of electrical conductors formed thereby. This allows the described electrical or electronic components 2, 4 to be contacted with the conductor track structure 1. Furthermore, the connection element 3 is implemented as a further electrical component 3, with the aid of which the conductor track structure 1 and the other components 2, 4 located thereon and electrically connected to the conductor track structure 1 are peripherally contacted. For this purpose, the connection element 3 according to the exemplary embodiment can be designed as a connection socket into which a correspondingly designed plug is inserted in order to ensure the desired electrical peripheral connection, as can be seen from the sectional view in Fig. 2.In this context, the cover 6 ensures that the conductor track structure 1 is protected from environmental influences. These environmental influences may include moisture, dust, etc., that may penetrate the housing. In fact, the design is such that the cover protects the conductor track structure 1, including the electrical components 2, 4 located thereon, from the environmental influences in question, although a connection area 3a of the connection element 3 is exposed in this context. This connection area 3a of the connection element 3 is equipped with connecting conductors 8, which can best be understood by comparing Fig. 1B and 2.In fact, the connecting conductors 8 in the exemplary embodiment run in an L-shape, specifically starting from the conductor track structure 1, initially vertically and then horizontally, so that the connecting conductors 8 according to the exemplary embodiment end predominantly horizontally inside the connecting element 3. This enables the previously described electrical contact of a plug inserted into the connecting element 3 with the conductor track structure 1 and the other electrical components 2, 4.

[0031] According to the invention, the cover 6 and / or the housing base 5 now has a receiving trough 9a, 9b for potting compound, which encompasses the previously mentioned and exposed connection area 3a. A comparative examination of Figs. 1D and 2 reveals that the receiving trough 9a, 9b is essentially formed in two parts. In fact, the receiving trough 9a, 9b is composed of a cover part 9b and a housing part 9a. The housing part 9a is integrally formed on the housing base 5. In fact, both the housing base 5 and the cover 6 are each designed as plastic injection-molded parts. Consequently, the cover part 9b is integrally formed on the cover 6.

[0032] It can be seen from Fig. 2 that the housing part 9a adjoins the cover part 9b with the interconnected conductor structure 1 interposed, and indeed, according to the exemplary embodiment, with the same contour. This means that the respective side walls of both the housing part 9a and the cover part 9b, which can be seen at this point in the sectional view according to Fig. 2, run largely parallel to one another and adjoin one another in plan view, so that the cover part 9b and the housing part 9a, in the installed state, form the receiving tray 9a, 9b for the potting compound, which is closed at the sides and bottom and open at the top. For this purpose, the potting compound can then be poured into the receiving tray 9a, 9b in question from above, as indicated by an arrow in Fig. 2.

[0033] In addition, it can be seen from the sectional view in Fig. 2 that the cover part 9b of the receiving trough 9a, 9b as well as the housing part 9a are each equipped with a molded-on clamp 10. According to the exemplary embodiment, the clamp 10 is U-shaped or inverted U-shaped, so that the connection element 3 is additionally mechanically held and precisely positioned to the housing or the housing base 5 as well as the cover 6. The cover 6 can additionally take on the function of a cover for the housing base 5. In principle, it is of course also possible to provide an additional cover with the help of which the housing base 5 is closed at the top in addition to the cover 6.

[0034] The sectional view in Fig. 2 further shows that the conductor track structure 1 is inserted into a groove 11 in the side wall of the receiving tray 9a, 9b or its housing part 9a facing the connection element 3. This positions and aligns the conductor track structure 1 with the electrical components 2, 4 located thereon relative to the housing base 5. Furthermore, the sectional view in Fig. 2 makes it clear that the side walls of the cover part 9b, as well as of the housing part 9a, which run away from the connection element 3, accommodate the conductor track structure 1 between them without any gaps, or at least largely without any gaps. This prevents any gaps from forming when the potting compound is poured into the receiving tray 9a, 9b, as shown by the arrow in Fig.2 any casting compound in a flowable state can flow into the area beyond the side walls in question, as is also shown by corresponding arrows in the sectional view of Fig. 2. In this way, the volumetric consumption of casting compound is reduced to a minimum and is actually concentrated only on the exposed connection area 3a of the connection element 3. Nevertheless, the casting compound can reach the housing part 9a of the receiving trough 9a, 9b in question via openings 12 present in this area in the conductor track structure 1 and can be seen in particular in Fig. 3A and here ensure the sealing of the ends of the connecting conductors 8 pushed through the conductor track structure 1.

[0035] The manufacture of the housing according to the invention is explained below, particularly with reference to the sequence of the individual production steps in Figs. 1A to 1D. Fig. 1A shows the housing base 5 with the seal 7. The seal 7 can be designed as an element attached separately to the housing base 5 or, in principle, also to the cover 6, or to both. According to the exemplary embodiment, however, only the housing base 5 is equipped with the seal 7 in question. For this purpose, the seal 7 can be applied to the housing base 5, for example as a foam bead or as an adhesive bead. A two-component production of the housing base 5 including the seal 7 is also possible, as described in detail in the introduction to the description.

[0036] The conductor track structure 1 is now inserted into or placed on the housing base 5 with the seal 7, or on the housing base 5 in question and the seal 7. For this purpose, the conductor track structure 1 is first and in a preceding step equipped with the electrical components 2, 4 arranged thereon, as well as with the connection element 3. This can be seen from the illustration in Fig. 1 B. In this context, the design is further such that, during this process, the capacitor 4, in the example case, finds space in a recess 5a of the housing base 5. This can be seen by comparing Figs. 1 A and 1 B.

[0037] Subsequently, the cover 6 is attached. The cover 6 now ensures that the conductor track structure 1 is completely covered and sealed against the housing base 5. Furthermore, the cover 6 is placed on the housing base 5 with the seal 7 interposed. This leaves a gap between the cover 6 and the housing base 5, which accommodates the conductor track structure 1 including the components 2, 4, at least for the most part in the exemplary embodiment. This can be seen in Fig. 1 C.

[0038] Figure 1C further illustrates that individual electrical components 2—according to the exemplary embodiment, the sensors or switches, and specifically microswitches 2—are also electrically connected to the conductor track structure 1, but are not accommodated in the space between the cover 6 and the housing base 5, but rather are located on the surface of the cover 6. Indeed, in this case, too, respective receiving troughs 6a are formed, enclosing an exposed connection area 2a of the microswitches 2, which—like the exposed connection area 3a of the connection element 3—are filled with the potting compound and thus sealed. The procedure may be comparable to that described in the applicant's DE 20 2008 015 696 U1, already mentioned in the introduction.

[0039] Finally, a cover may be placed on top, which closes the housing base 5, including the conductor track structure 1 located inside, as well as the cover 6. This is not mandatory, however, because the cover 6 can also simultaneously assume the function of the cover. This naturally only happens when the potting compound in the area of ​​the receiving tray 9a, 9b as well as the additional receiving tray 6a has hardened. It can be seen that both the respective receiving tray 6a and the receiving tray 9a, 9b, which is particularly relevant according to the invention, are each designed as a rectangular tray open at the top according to the exemplary embodiment. Both rectangular trays 6a; 9a, 9b each enclose the connecting conductor 8 or an exposed connection area 3a, 2a and, after the potting compound has hardened, ensure a corresponding and desired seal.

[0040] List of reference symbols

[0041] Conductor track structure 1

[0042] Components 2, 4

[0043] Microswitch 2

[0044] Connection area 2a

[0045] Connection element 3

[0046] Connection area 3a

[0047] Capacitor 4

[0048] Case back 5

[0049] Recess 5a

[0050] Cover 6

[0051] Receptacles 6a

[0052] Seal 7

[0053] Connecting conductor 8

[0054] Receptacle 9a, 9b

[0055] Housing part 9a

[0056] Cover part 9b

[0057] Bracket 10

[0058] Slot 11

[0059] Openings 12

Claims

Patent claims 1. Housing for automotive applications, in particular motor vehicle lock housings, preferably motor vehicle door lock housings, with an electrical connection element (3) for peripheral contacting of a conductor track structure (1) which is electrically and mechanically connected to the connection element (3) and has electrical components (2, 4) arranged thereon in the housing interior, and with a cover (6), wherein a connection region (3a) of the connection element (3) is exposed with respect to the cover (6) for the conductor track structure (1) which protects against environmental influences, characterized in that the cover (6) and / or a housing base (5) has a receiving trough (9a, 9b) for casting compound which encompasses the exposed connection region (3a).

2. Housing according to claim 1, characterized in that the cover (6) preferably completely covers the conductor track structure (1) and is sealed off from the housing base (5).

3. Housing according to claim 1 or 2, characterized in that the cover (6) is placed on the housing base (5) with the interposition of a seal (7).

4. Housing according to one of claims 1 to 3, characterized in that an intermediate space between the cover (6) and the housing base (5) largely accommodates the conductor track structure (1) including the components (2, 4).

5. Housing according to one of claims 3 or 4, characterized in that the seal (7) is designed as an element attached separately to the housing base (5) and / or the cover (6), for example an applied bead of foam or an adhesive.

6. Housing according to one of claims 3 to 5, characterized in that the seal (7) forms a structural unit (5, 7; 6, 7) manufactured together with the housing base (5) and / or the cover (6), for example a two-component injection-molded part.

7. Housing according to one of claims 1 to 6, characterized in that the receiving tray (9a, 9b) is designed as a rectangular tray which encloses all the connecting conductors (8) of the connecting element (3) and is open at the top.

8. Housing according to one of claims 1 to 7, characterized in that the receiving trough (9a, 9b) is formed in two parts essentially from a cover part (9b) and a housing part (9a).

9. Housing according to claim 8, characterized in that the housing part (9a) adjoins the cover part (9b) with the interconnection of the conductor track structure (1), preferably with the same contour.

10. Housing according to claim 8 or 9, characterized in that the cover part (9b) and the housing part (9a) in the installed state define the receiving trough (9a, 9b) which is closed laterally and downwards and open upwards.

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