DE102008005669A1 - Lining part i.e. instrument panel, for motor vehicle, has border strips sectionally running between carriers and opening flap, where adhesion between plastic of strips and plastic of flap is smaller than cohesion of plastic of opening flap - Google Patents

Abstract

The part (1) has an opening flap (12) attached on carriers (11), and border strips (13) sectionally running between the carriers and the opening flap. The border strips are made of plastic e.g. thermoplastic elastomer. The carriers and the opening flap are made of identical plastic i.e. polypropylene, in an area of the border strips. Adhesion between the plastic of the strips and the plastic of the carriers is smaller than cohesion of the plastic of the carriers. Adhesion between the plastic of the strips and the plastic of the flap is smaller than the cohesion of the plastic of the flap. An independent claim is also included for a method for manufacturing a lining part for a motor vehicle.

Description

object The present invention is a trim part for a motor vehicle with a carrier and one on the carrier arranged opening flap, wherein between the carrier and the opening flap at least partially a border runs and the carrier and the opening flap have a plastic. Furthermore, a method for the production of such a trim part explained.

conventional be used in trim parts, especially interior trim parts, which comprise an airbag cover device, between the carrier and the opening flap weakening lines introduced around an opening of the opening flap through the to guarantee unfolding airbag. Such lines of weakness are mostly by means of perforations or material weakenings produced.

For example, the document shows EP 0 779 185 A2 an airbag covering device, in which the wall thickness of the carrier is reduced along a border to a residual wall thickness, so that an airbag pressing on the cover opens the airbag cover along the border and the airbag can escape to the outside.

An alternative solution for introducing the weakening lines is in the document WO 99/58375 shown in which the airbag cover is perforated along its border with a laser, whereby the material is weakened so much that pressed onto the airbag cover airbag pushes the cover along the introduced lines of weakness along the border or along the border. Disadvantages of the aforementioned solutions are, on the one hand, the additionally necessary step of introducing the weakening or the perforation and, on the other hand, the at least uneven surface of the trim part in the region of the border, which makes subsequent processing of the trim part more difficult.

task The invention is to provide a cowling, in which the above problems do not occur.

The Invention solves the problem, with a fairing part according to the features of claim 1 and a method for manufacturing A trim piece according to claim 7.

advantageous Further developments of the invention are in the subordinate claims disclosed.

Of the Carrier and the opening flap have a plastic on. Between the carrier and the opening flap a border runs along which the opening flap can be moved out of the plane of the carrier and thus allowing passage of the airbag. The border points a plastic, wherein the adhesion between the plastic the border and the plastic of the carrier is smaller as the cohesion of the plastic of the carrier and / or the adhesion between the plastic of the border and the plastic of the opening flap is smaller than the cohesion the plastic of the opening flap.

With the expression of a "smaller adhesion than cohesion" is meant here that acting due to an adhesion Binding forces between two different plastics or plastic mixtures are smaller or smaller than those due to Cohesion-acting bonding forces within a individual plastic or plastic mixture.

The acting cohesive forces can, for example, be measured by measuring the tensile modulus and / or tensile breaking strength ISO 527 / 1B or the modulus of elasticity and / or the bending strength after ISO 178 be determined. For an exemplary plastic of the support PP / LGF 20, reinforced with 20% glass fiber polypropylene (z. B. manufactured by Sabic ^®), total these values, measured at 23 ° C, to 4800 MPa (tensile modulus), 81 MPa ( Tensile breaking strength), 4100 MPa (modulus of elasticity) and 116 MPa (transverse rupture strength). These values are only guideline values and may differ for other materials. The values for the plastic of the carrier should preferably be greater than 1000 MPa (tensile modulus), 50 MPa (tensile breaking strength), 1000 MPa (elastic modulus) and 50 MPa (bending strength), more preferably greater than 2000 MPa (tensile modulus), 70 MPa Tensile strength), 2000 MPa (modulus of elasticity) and 70 MPa (flexural strength).

The acting adhesion forces between the plastic the support and the plastic of the border must - like already mentioned - smaller than the above Be cohesive forces.

Thereby, that the plastic of the border is made of at least the plastic the carrier or the plastic of the opening flap differs, and these at least two different plastics have only a slight adhesion to one another, when triggered, one of the opening flap below lying airbags the opening flap due to the low Bonding force between the at least two plastics pressed.

This means, in particular, that the at least two plastics of the border and of the carrier and / or the opening flap can not be closed set of adhesion promoters can enter into a firm connection with each other and the opening flap could withstand the pressure of an opening flap below the deploying airbag.

At the Triggering one below the carrier or the opening flap lying airbags, the airbag pushes the opening flap along the border. Looking at the carrier or the opening flap as a first standard cuboid and the border as a second standard cuboid, it works either a big one Force on the first or second standard cuboid, resulting in a shearing force between the first and second adjoining standard cuboid leads. The invention does not exclude that the first and the second standard cuboid, d. h., the plastic of the wearer and / or the opening flap and the plastic of the border tie together. The adhesion between the two materials just has to be chosen so that due to a triggered Airbags acting shear forces are stronger than the adhesive interaction between the at least two plastics.

advantageously, However, there is essentially no adhesion between the plastic of the border and the plastic of the wearer or the plastic of the border and the plastic of the opening flap. In this case, it is particularly advantageous that areas of the plastic the border and the areas of the plastic of the wearer and / or the opening flap along a severing line strictly are separated from each other. This will create a smooth elevation along the border allows. Due to that no adhesion between the plastic of the border and the plastic of the carrier and / or the opening flap is present, is guaranteed that the opening flap open when needed can.

Farther It is advantageous if the carrier and the opening flap at least in the area around the border around an identical plastic exhibit. Particularly preferably, the carrier and the opening flap in the area around the border around an identical plastic. This holds especially in the production the trim part advantages, as this only two plastic mixtures or plastics used for the trim part must, for one thing, for the wearer and the opening flap and the other for the border. This simplifies the production.

there It is particularly advantageous if the carrier and the opening flap at least in the area of the border of polypropylene or of a filled one or reinforced polypropylene are made and the border is made of a plastic, which in conjunction with the aforementioned polypropylene materials a weak adhesive interaction shows. These are preferably the plastics PA 6, PA 6.6, PA blend, PBT, PPO or plastics from the material group of the thermoplastic Elastomers (TPE), such as TPU. Also are combinations possible from the aforementioned plastics, as long as the Adhesion between the polypropylene materials and the plastic the border is less than the cohesion of the polypropylene material taken individually. Furthermore, it is advantageous if the Border is made of a plastic, which is made with the polypropylene materials shows no adhesive interaction, such as ABS, ASA, CA, PC, PC / ABS, PC / PBT, PC / PET, PMMA or LSR or vice versa a material from the material group of TPEs.

Farther it is advantageous if the wearer the opening flap and the border facing on an interior of a vehicle Form a flat surface.

Farther it is advantageous that on a side facing the interior the trim part a decorative layer and / or a foam layer available. In this way, one for the viewer or occupants of the vehicle pleasant feel of the trim panel be achieved.

The Method for producing a trim part for a Motor vehicle, wherein the trim part a carrier and an opening flap comprises the following steps: On the one hand, a plastic is introduced into a tool and inside the tool of the carrier and / or the opening flap produced. It may be in the plastic of the wearer and the plastic of the opening flap by two different Plastics or plastic mixtures or plastics with metal inserts act. Furthermore, a border, which is located between the Carrier and the opening flap is located with a Plastic filled, with the adhesion between the plastic of the border and the plastic of the wearer smaller than the cohesion of the plastic of the carrier and / or the adhesion between the plastic of the border and the plastic of the opening flap is smaller than the Cohesion of the plastic of the opening flap. On this way, as in the previously described subject of the trim panel, achieved when pressing one below the trim panel lying airbags the opening flap due to the lack of Binding forces between the plastics opened along the border becomes.

The method is particularly advantageous when the plastic of the carrier with the plastic or plastic mixture of the opening flap is identical and the carrier and the opening flap in a tool, preferably in one step, are produced. This simplifies the manufacturing process.

there it is particularly advantageous, although the border between the carrier and the opening flap after or at the same time in the manufacture of carrier and opening flap is introduced. This can be done within the framework of well-known multicomponent or two-component process, for example a nuclear retraction process or a displacement method. Further advantageous Further developments can the further subordinate claims and the embodiments are taken.

in the The invention is based on several embodiments be explained in more detail. Show it:

1a , b different embodiments of the trim parts;

2a , b cross-section through an embodiment of the trim part;

3 Embodiment of the trim part with foam and decorative layer.

In 1a is a cowling 1 shown which in the illustrated embodiment as an instrument panel 10 is trained. The instrument panel 10 consists of a carrier 11 on which an opening flap 12 is arranged. The carrier 11 and the opening flap 12 are made in a manufacturing process of polypropylene (PP) with glass fiber additives.

Between the carrier 11 and the opening flap 12 there is a border 13 which the opening flap 12 circumscribes on three sides. If an airbag is triggered, the opening flap opens 12 along the border 13 and stays over the axis 14 firmly with the carrier 11 connected.

The border 13 In the case illustrated here, it is made of a TPE. The TPE material and polypropylene show a low degree of adhesion, but this is the measure of the cohesion of the polypropylene of the carrier 11 or the opening flap 12 far from exceeding. In this way, a functional opening of the opening flap 12 along the border 13 guaranteed.

Instead of the TPEs, PA 6 or PA 6.6 or a PA blend as well as PPO could also be used. All the aforementioned plastics have a low adhesion to polypropylene. Also suitable would be plastics such as ABS, ASA, CA, PC, PC / ABS, PC / PBT, PC / PET, PMMA or LSR, all of which are not binding with polypropylene. Due to the use of polypropylene to make the instrument panel 10 and the use of the more expensive plastic TPE along the border 13 For example, in a multi-component injection molding process, an instrument panel carrier having a functioning opening flap 12 in one or two working steps.

It is easy to see that the outline 13 sharp from the carrier 11 the opening flap 12 is disconnected. Furthermore, the border not only runs along the three sides in the plane of the carrier, but also perpendicular thereto, ie, in dimension of the thickness of the carrier 11 , That is, that the border 13 along the entire thickness of the carrier 11 runs and is filled with PBT. Other plastic combinations, which are suitable, can be, for example, the Saechtling Plastic Pocketbook, p. 693, Hansa Verlag, 29 , Output or manufacturer information from plastics such as Krauss-Maffei, Mattenfeld or Bayer Materials.

In the 1b is an embodiment of a trim part 1' shown. Shown is a steering wheel 30 which is a carrier 31 and because of the geometry of the border 33 two opening flaps 32 . 32 ' and two axes 34 . 34 ' having. From the operation of the opening of the airbag changes from the in 1a not shown. Only because of the different geometry of the border 33 open two independently moving opening flaps 32 and 32 ' , The carrier 31 is constructed from a TPU. The border 33 consists of POM. There is no adhesive interaction between the two, so that an opening of the opening flaps 32 . 32 ' can be ensured by a triggering airbag.

In the 2a is a cross-section I through the instrument panel 10 of the 1a shown. It can be seen that the outline 13 from the carrier 11 or the opening flap 12 along the straight lines 41 respectively. 42 is disconnected. When triggering a lying below the instrument panel airbags 45 push this with a directed in the direction of arrow F force against the opening flap 12 , these along the border 13 due to the choice of material opens and so the passage of the airbag 45 allowed.

In the 2 B is another cut II through the dashboard 10 shown. This cut is transverse to in 2a shown section. Again, it can be seen that the outline 13 sharp from the carrier 11 and the opening flap 12 different. Furthermore, it can be seen that on the side facing away from the vehicle interior of the instrument panel 10 a notch 46 exists, which provides better rotation of the opening flap 12 around the axis 14 allows. The instrument panel 10 has a side facing the vehicle interior 17 on, which runs essentially without bumps. This means that with appropriate color design of the plastic of the border 13 or the polypropylene of the carrier 11 or the opening flap 12 can be dispensed with a further decorative layer. The score 46 is not mandatory for the operation of the invention.

As an embodiment, the border may have a width of 0.1 mm to 3 cm, preferably between 1 mm and 1 cm between the lines 41 and 42 exhibit.

Furthermore, the border can also have a "blurred" area, ie that the lines 41 and 42 not straight and not exactly defined. Rather, the concentration of a plastic or plastic mixture increases between the carrier and the opening flap, wherein this plastic does not or only poorly binds with the plastic or plastic mixture of the carrier and / or the opening flap. The border is formed by the concentration gradient between the different plastics. Therefore, z. B. the plastic of the border sprayed with increased pressure in the tool and displaces the plastic of the carrier or the opening flap, thus forming the border (displacement method).

To the trim part, as in 3 It can be equipped with a foam layer 15 and a decorative layer 16 be connected so as to produce a pleasant for the occupant of the vehicle feel. It changes at the egg tual opening mechanism due to the different adhesion and cohesion forces compared to those in the 1 and 2 shown embodiments nothing. On the basis of in 3 shown border 13 should be noted that the in 3 shown and in cross-section cuboid geometry of the border 13 can also be replaced by another geometry, such as a T-shaped geometry, which may have the crossbar of the "T" on the side facing the passenger compartment or the side facing away from the passenger compartment of the carrier.A T-shaped geometry can also be used with the other embodiments and applications are combined.

at the use of a trim part according to the invention It may be during the opening of the airbag flap too a particle flight of the plastic of the wearer and in particular come from the plastic of the border. For example, this particle flight can by introducing a supporting foil, a gluing the Border with a foam layer, a cross-sectionally T-shaped Outline as described above or other from the prior Technique known devices or methods can be prevented.

At This point should be noted that such a trim part can also be used outside of vehicles, For example, in external airbags for the protection of pedestrians.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• EP 0779185 A2 [0003]
• WO 99/58375 [0004]

Cited non-patent literature

• - ISO 527 / 1B [0010]
• - ISO 178 [0010]
• - Saechtling Kunststofftaschenbuch, p. 693, Hansa Verlag, 29 [0031]

Claims (10)

Cowling ( 1 . 1' ), for a motor vehicle with a carrier ( 11 ; 31 ) and an opening flap attached to the carrier ( 12 ; 32 . 32 ' ), wherein between the carrier and the opening flap at least partially a border ( 13 ; 33 ' ) and the carrier and the opening flap comprise a plastic, characterized in that the border has a plastic, wherein the adhesion between the plastic of the border and the plastic of the carrier is smaller than the cohesion of the plastic of the carrier and / or the adhesion between the plastic of the border and the plastic of the opening flap is smaller than the cohesion of the plastic of the opening flap. Cowling ( 1 . 1' ) according to claim 1, characterized in that substantially no adhesion between the plastic of the border and the plastic of the carrier is present and / or there is substantially no adhesion between the plastic of the border and the plastic of the opening flap. Covering part according to claim 1 or 2, characterized characterized in that the carrier and the opening flap at least in the area of the border an identical plastic exhibit. Covering part according to one of the preceding claims, characterized in that the carrier and the opening flap at least in the area of the border are made of polypropylene and the border is made of a plastic, which with Polypropylene or a filled or reinforced Polypropylene shows a weak adhesive interaction, preferably a thermoplastic elastomer (TPE) or the border is made of a plastic, which with polypropylene or a filled or reinforced polypropylene no adhesive interaction, preferably ABS, ASA, CA, PC, PC / ABS, PC / PBT, PC / PET, PMMA or LSR. Trim part according to one of the preceding claims, characterized in that the carrier, the opening flap and the border on a side facing an interior of a vehicle side a flat surface ( 17 ) form. Covering part according to one of the preceding claims, characterized in that on a side facing the interior a decorative layer ( 16 ) and / or a foam layer ( 15 ) is available. Method for producing a trim part for a motor vehicle, wherein the trim part a Carrier and has an opening flap, and the Procedure includes the following steps: a) introduce a plastic in a tool and manufacture of the carrier and the opening flap; b) completing a located between the carrier and the opening flap Border with a plastic, with the adhesion between the plastic of the border and the plastic of the carrier smaller is considered the cohesion of the plastic of the wearer and / or the adhesion between the plastic of the border and the plastic of the opening flap is smaller than the Cohesion of the plastic of the opening flap. Method according to Claim 6, characterized that the plastic of the carrier with the plastic of the opening flap is identical and the carrier and the opening flap in a tool, preferably in one step, at the same time getting produced. Method according to one of claims 6 or 7, characterized in that the border between the carrier and the opening flap after or at the same time in the production is introduced by the carrier and opening flap. Method according to one of claims 6 to 8, characterized in that on the covering part a foam layer and / or a decorative layer is applied.