Decorative element and airbag module cover

Abstract

A decorative unit (5) is described which is designed as part of an airbag module cover (60). This decorative unit comprises a first transparent or translucent part (10) with a surface comprising a front surface section (12) and a rear surface section, an illumination part (30) with at least one light-emitting element for at least indirectly emitting light onto the surface of the first transparent or translucent part (10), and a housing part (40) made of metal and having a side wall (41) surrounding at least the illumination part (30). In order to improve the visual appearance of the decorative unit (5), at least one recess (16) extends into the surface of the first transparent or translucent part (10) which is not the front surface section (12). This recess (16) has at least one radial portion and / or section.Furthermore, the housing part (40) comprises at least one front connecting section (42) which is located at least partially within the at least one recess (16) which extends into the surface of the first transparent or translucent part (10).

Description

[0001] The invention relates to a decorative element according to the preamble of claim 1 and to an airbag module cover according to claim 10.

[0002] In particular, the airbag module cover of a driver airbag module located in the steering wheel hub often comprises a main body and a decorative element attached to this main body. This decorative element often includes the vehicle manufacturer's logo.

[0003] To improve the visual effect of this decorative unit, it is known to provide this decorative unit with a lighting part (usually a printed circuit board (PCB) with several LEDs) and a first transparent or translucent part that is directly or indirectly illuminated by this lighting part. This first transparent or translucent part naturally has an outer surface that includes at least a front section (the section visible from the interior of the vehicle) and a rear section. The decorative unit must therefore include at least the aforementioned first transparent or translucent part and the aforementioned lighting part. Normally, a light guide is additionally provided between the lighting part and the first transparent or translucent part, and an end plate behind the lighting part is often also required.Of course, these elements must be “held together,” and therefore a housing part is usually provided, which can also serve to attach the entire decorative unit to the main part of the airbag module cover.

[0004] Many proposals have been made in the prior art for the design of such a decorative unit, in particular its housing, but many of them are either complicated to manufacture and assemble (in particular because they consist of too many parts) or are aesthetically unsatisfactory.

[0005] Based on this prior art, the object of the invention is to provide a decorative unit which is simple to manufacture and robust enough to remain fully attached to the main part of the airbag module cover during airbag deployment, and which is visually appealing.

[0006] This object is achieved by a decorative unit according to claim 1. An airbag module cover consisting of a main part and such a decorative unit is defined in claim 10.

[0007] According to the invention, the decorative unit has several features, the combination of which makes it possible to provide a decorative unit which has the desired properties.

[0008] According to one feature of the invention, the housing part is made of metal. The use of metal has several advantages over the use of a plastic material: Firstly, the housing part can be designed to be lightweight and thin-walled while still offering the required stability. Secondly, the use of metal often allows the housing part to be made in one piece, thereby reducing the number of assembly steps. The disadvantage of using a metal housing part is that it is often undesirable for parts of the metal housing part to be visible after final assembly of the airbag module cover. Therefore, measures must be taken to ensure the "invisibility" of the housing part. According to a further feature of the invention, at least one recess extends into the surface of the first transparent or translucent part in such a way that this recess is not visible.This means that this recess extends into a different section of the surface of the first transparent or translucent part than the front surface section. The housing part comprises at least one front connecting section that connects the first transparent or translucent part to the housing part. This front connecting section extends from a side wall of the housing part and is located at least partially within the at least one recess that extends into the surface of the first transparent or translucent part. Since the recess does not start from the front surface section of the first transparent or translucent part, the housing part does not extend to this front surface and can therefore be designed such that it is not visible after the decorative unit has been mounted on the main part of the airbag module cover.This naturally means that the housing part does not encompass the first transparent or translucent part at its front. To compensate for this, the recess has at least one radial portion and / or section, creating a force-locking connection in the axial direction between the first transparent or translucent part and the housing part, namely its front connecting section.

[0009] These measures create a decorative unit with a uniform and continuous exterior surface. This uniform and continuous exterior surface is aesthetically pleasing.

[0010] Normally, it is preferred that the at least one front connecting portion extends radially inwardly from the side wall of the housing part so that no additional space is required radially outside the side wall of the housing.

[0011] It is often preferred that the housing part holds all elements of the decorative unit together, and for this reason, it is often preferred that the housing part further comprise at least one rear connecting portion axially spaced from the at least one front connecting portion. This rear connecting portion holds the lighting part at least indirectly. Since the housing part is made of metal, it is preferred that this rear connecting portion be created by radially deforming a housing part precursor as the final assembly step.

[0012] It is possible to provide a single rear connecting section, for example in the form of a circumferential deformation of the side wall of the housing part. Alternatively, several spaced rear connecting sections, particularly in the form of tabs or eyelets, can be provided. The same applies to the front connecting section.

[0013] As is generally known, a second transparent or translucent part, in particular in the form of a light guide, can be provided between the lighting part and the first transparent or translucent part.

[0014] In one embodiment, the first transparent or translucent part is molded onto the housing part, so that the at least one recess is formed mainly by the front connecting portion during the injection molding process. This creates a very tight and secure connection between the front connecting portion and the first transparent or translucent part. This enables a robust and precise connection between the first transparent or translucent part and the housing part. In particular, it allows the other internal components to be accommodated without specific fastening to the first transparent or translucent part. Thus, the latter can be free of fastening devices (usually a protruding centering pin arranged for hot stamping) that could impair light scattering or homogeneity.

[0015] Alternatively, the first transparent part can be a prefabricated part, and the at least one front connecting section is formed into the at least one recess. This has the advantage that no sophisticated molding tool is required.

[0016] Typically, the housing part also includes mounting tabs for attaching the decorative unit to a vehicle part, in particular to a main part of an airbag module cover. These mounting tabs can be integral with the side wall of the housing part.

[0017] The invention will now be described using preferred embodiments with reference to the accompanying figures. The figures show: Fig. 1 a housing part precursor of a housing part made of metal in a side view, Fig. 2 a view from direction R1 in Fig. 1, Fig. 3 a section of the housing part pre-stage Fig. 1, Fig. 4: the housing part preamplifier from Fig. 3, after a first transparent or translucent part has been molded onto it, Fig. 5: the subassembly from Fig. 4, a light guide and a printed circuit board with LEDs, Fig. 6: the subassembly from Fig. 4, wherein the light guide and the circuit board are made of Fig. 5 are inserted between the side wall of the housing part pre-stage, Fig. 7: the elements from Fig. 6 after bending the rear connecting sections of the pre-stage of the housing part, so that the housing part pre-stage becomes the housing part and the assembly process of the decorative unit is completed, Fig. 8: the decorative unit from Fig. 7 and a section of a main part of an airbag module cover, Fig. 9 which in Fig. 8, after the decorative unit has been inserted into a recessed section of the main part of the airbag module cover made of Fig. 8 was used, Fig. 10 which in Fig. 9, after the fastening tabs of the housing part have been bent to attach the decorative unit to the main part of the airbag module cover, Fig. 11 a first transparent or translucent part and the front section of a housing part precursor of a second embodiment in a schematic cross-sectional view, Fig. 12 which in Fig. 11, after a portion of the first transparent or translucent part has been inserted into the pre-stage of the housing part, Fig. 13 which in Fig. 12 elements shown after the front connecting section has been created, Fig. 14 is a realistic plan view of the recessed portion of a main part of an airbag module cover of a second embodiment of the invention, Fig. 15 the inside of the recessed section Fig. 14, Fig. 16 the decorative unit of the second embodiment in a perspective view, Fig. 17 is a perspective view of the airbag module cover of the second embodiment of the invention after the decorative unit of Fig. 16 in the recessed portion of the main body of the airbag module cover Fig. 14 was mounted, and Fig. 18 essentially what is in Fig. 17 is shown, in a cross-sectional view.

[0018] The invention is first described using the assembly process of a schematically illustrated first embodiment with regard to the Fig. 1 to 10 are described in detail.

[0019] The Fig. 1 to 3 show a housing part precursor 40', which is transformed into a housing part 40 during the assembly process. This housing part precursor 40' comprises a side wall 41, which has the shape of a hollow cylinder, and a front connecting portion 42, which extends from a front end portion 41a of the side wall 41 in the radial direction D R extends inwards (see in particular Fig. 2 and Fig. 3). The front connecting portion 42 has the shape of a continuous ring, but in other embodiments, several separate front connecting portions could be provided, in which case, too, it is preferred that these separate front connecting portions extend inward. The housing part precursor 40' further comprises parts 44' (in the form of tabs) that extend substantially axially from the rear end 41b of the side wall 41, and fastening tabs 46 that also extend from the rear end portion 41b of the side wall 41. The parts 44' become rear connecting portions 44 during the assembly process, as will be seen later. In the illustrated embodiment, the parts 44' and the fastening tabs 46 extend not only from the rear end portion 41b of the side wall, but also from the rear end edge of the side wall 41.

[0020] In a first assembly step, a first transparent or translucent part 10 is molded onto the front end portion of the housing part precursor 40', i.e., onto the front end portion 41a of the side wall and the front connecting portion 42, such that the front connecting portion 42 projects into this first transparent or translucent part 10. The first transparent or translucent part 10 naturally has a surface comprising a rear surface portion 11, a front surface portion 12, and a side surface portion 14. Since the first transparent or translucent part 10 is molded onto the housing part precursor 40', in particular around the front connecting portion 42, a recess is formed that extends from the surface of the first transparent or translucent part and receives the front connecting portion 42.In other words: This recess is or comprises the negative form of the front connecting section 42 and thus, since the front connecting section 42 extends radially inward, the recess also extends from its surface, here from its side surface section 14, radially into the first transparent or translucent part 10. It is not necessary for this recess 16 (and the front connecting section 42) to run entirely in the radial direction, but it must have a radially extending part or a radially extending portion, so that a force-fitting connection is created between the front connecting section 42 and the first transparent or translucent part 10 not only in the radial direction, but also in the axial direction.

[0021] In the subsequent assembly step(s), a second transparent or translucent part in the form of a light guide 20 and an illumination part 30—a circuit board carrying at least one light-emitting element, typically a plurality of LEDs 32—are inserted from the rear end side of the side wall 41, such that a front surface of the light guide 20 is in contact with, or at least in close proximity to, the rear surface portion 11 of the first transparent or translucent part 10. The provision of such a second transparent or translucent part is often preferred but is not mandatory in all embodiments. In any case, an illumination part must be provided such that the light emitted by this illumination part is guided directly or indirectly into the first transparent or translucent part 10, typically into its rear surface portion 11.

[0022] In a next step, the parts 44' of the housing precursor are bent inward to form the rear connecting sections 44 of the housing part 40. The assembly process of the decorative unit 5 is now complete.

[0023] Next, this decorative unit 5 is mounted to the main part 50 of an airbag module cover, particularly for driver-side applications. This main part 50 of the airbag module cover comprises a base body 52, which is a molded plastic part, and optionally a cover 54, which is typically made of leather or synthetic leather. The main part 50 of the airbag module cover includes a recessed portion 56 for receiving the decorative unit 5. Through-holes 58 for the fastening tabs 46 of the housing part 40 and a through-hole for the electrical cable 34 extending from the lighting part 30 are provided, as is generally known in the art.

[0024] As in the Fig. 9 and Fig. As shown in Figure 10, the decorative unit 5 is inserted into the recessed portion 56 from the outside of the main body of the airbag module cover, so that portions of the fastening tabs 46 extend through the aforementioned through-holes 58. These fastening tabs 46 are then bent to fasten the decorative unit 5 to the main body 50 of the airbag module cover, thus completing the assembly of this airbag module cover 60. The fastening tabs can additionally be riveted, hot-stamped, screwed, or glued to the base body 52. ​​The recess provides a large support surface for the decorative unit 5, which is advantageous for robust and simple fastening.Such a recessed portion 56, which requires insertion of the decorative unit 5 from outside the airbag module cover, is particularly suitable for airbag module covers wrapped with a cover 54, since it allows the ends of the cover 54 to be easily accommodated and concealed.

[0025] Now a second embodiment is presented with regard to the Fig. 11 to 13. Although it is often preferred to mold the first transparent or translucent part 10 onto the housing 40 or its precursor 40', it is also possible to provide a prefabricated first transparent or translucent part 10 that already includes the at least one recess. In this case, it is possible, for example, to produce the front connecting portion 42 (or a plurality of front connecting portions) by deforming the part 42' of the housing precursor 40', for example, by crimping, as shown in FIGS. Fig. 12 and Fig. 13 shown.

[0026] The Fig. 13 to 18 show a third embodiment which is very similar to the first embodiment, but is shown in a more realistic representation. In Fig. 14 shows a central portion of a main part 50 of an airbag module cover with a recessed portion 56. One can see the through holes 58 for the fastening tabs as well as a through hole 57 for a cable that must normally be provided for the power supply of the lighting part 30 of the decorative unit 5.

[0027] As from Fig. 15, which shows a rear view of the recessed portion 56, receptacles 59 for the fastening tabs can be provided in order to further secure the decorative unit 5 to the main part of the airbag module cover.

[0028] In Fig. 16 shows a complete decorative unit 5, Fig. 17 shows the decorative unit 5, which is housed in the recessed portion 56 and attached to the main part of the airbag module cover. Fig. 18 shows the same as Fig. 17, but in a cross-sectional view.

[0029] In this embodiment, the decorative unit further comprises an end plate 35 at the rear of the lighting part 30. This end plate 35 advantageously protects the rear of the lighting part 30 and can also better support optional sealing elements. Sealing elements or devices can be provided to protect against moisture and to prevent light loss through the rear of the decorative unit 5. Another difference from the first embodiment is that the front connecting portion of the housing part extends partially into the rear surface portion of the first transparent or translucent part 10.

[0030] From the described embodiments, it is clear that the decorative unit can be easily assembled from a minimum of parts, can be designed to be very stable due to the all-metal housing, and is visually appealing, as only the first transparent or translucent part is visible from the interior of the vehicle. The first transparent or translucent part typically displays the vehicle manufacturer's emblem on its front. List of reference symbols 5 decorative unit 10 first transparent or translucent part 11 rear surface section 12 front surface section 14 lateral surface section 16 Recess in the side surface (an annular groove or several recesses) 20 second translucent or light-permeable element (light guide) 30 Lighting part (circuit board with LEDs) 32 LED 34 cables 35 End plate 40 Housing part 40' cabinet preamplifier 41 Side wall 41a front end section of the side wall 41b rear end section of the side wall 42 front connecting section 42' Part of the housing preamplifier that is crimped to the front connection section 44 rear connecting section 44' Part of the housing pre-stage, which is bent to the rear connecting section 46 Mounting tab 50 Main part of the airbag module cover 52 basic bodies 54 leather cover 56 recessed section of the airbag module cover to accommodate a decorative unit 57 Through hole for cable 58 Through hole for mounting bracket 59 Mounting bracket 60 Airbag module cover D A axial direction D Rradial direction

Claims

[1] Decorative unit (5) designed as part of an airbag module cover (60) and comprising: a first transparent or translucent part (10) with a surface, comprising a front surface portion (12) and a rear surface portion (11), wherein the front surface portion (12) is in an axial direction (D A ) defines a first end of the decorative element (5), a lighting part (30) having at least one light-emitting element for at least indirectly emitting light onto the surface of the first transparent or translucent part (10), which is not the front surface portion (12), a housing part (40) with a side wall (41) which surrounds at least the lighting part (30), characterized by , that at least one recess (16) extends into the surface (14) of the first transparent or translucent part (10) which is not the front surface section, wherein the recess has at least one radial portion and / or section, the housing part (40) is made of metal, the housing part (40) has at least one front connecting section (42), wherein the front connecting section (42) is located at least partially within the at least one recess (16) which extends into the surface (14) of the first transparent or translucent part (10). [2] Decorative unit according to claim 1, characterized by that the at least one front connecting section (42) extends inwards from the side wall (41) of the housing part (40). [3] Decorative unit according to claim 1 or 2, characterized bythat the housing part (40) further comprises at least one rear connecting portion (44) which is axially spaced from the at least one front connecting portion (42) and at least indirectly holds the lighting part (30). [4] Decorative unit according to claim 3, characterized by that the at least one rear connecting section (44) is produced by plastic deformation of at least one part (44') of a housing part precursor (40') from which the housing part (40) is produced. [5] Decorative unit according to one of claims 3 or 4, characterized by that a plurality of rear connecting sections (44) are provided, each rear connecting section (44) being an inwardly bent section of the housing. [6] Decorative unit according to one of the preceding claims, characterized bythat a second transparent or translucent part (20) is provided between the lighting part (30) and the first transparent or translucent part (10). [7] Decorative unit according to one of the preceding claims, characterized by that the first transparent or translucent part (10) is injection-molded onto the housing part (40) so that the at least one recess (16) is formed during the injection-molding process. [8] Decorative unit according to one of claims 1 to 6, characterized by that the first transparent or translucent part (10) is a prefabricated part and the at least one front connecting section (42) is deformed into the at least one recess (16). [9] Decorative unit according to one of the preceding claims, characterized by that the housing part (40) further comprises fastening tabs (46) for fastening the decorative unit (5) to a vehicle part, in particular to a main part (50) of an airbag module cover. [10] An airbag module cover (60) comprising a main body (50) and a decorative unit (5) according to claim 9, which is attached to the main body (50) by means of the fastening tabs.

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