COMPOSITE CONSTRUCTION PART FOR VEHICLE BODIES

The invention refers to a composite construction part for vehicle bodies, in particular for vehicle roofs, according to the generic term of the patent claim 1.

Erfindungsgemäß trained composite construction parts are in principle einschlie&szlig for all surface ranges of vehicle bodies; lich the hoods, doors and flaps/covers, suitably, for which apart from a sufficient becoming baggy rigidity and firmness such as bending strength and torsional strength with small weight good warming and/or sound isolation characteristics are required. If from a vehicle roof and/or a hood the speech is following, it concerns preferential application places of the invention, however without meaning restrictive on it.

In order to achieve with a well-known roof system (GM 79 29 367 U1) in the generic term of the patent claim 1 indicated training a sufficient becoming baggy rigidity, a first separate torsionally stiff semi-finished material profile framework is to be made, which is to be fastened then to the roof membrane along their edges inseparably. The up-foamed plastic film covers also the semi-finished material profile framework connected inseparably with the roof membrane. From light alloy or from plastic if existing roof membrane is to be reinforced effectively against indenting, at least transverse to the side members of the semi-finished material profile framework an extending profile prop is to be been careful after the well-known proposal. The well-known roof system requires a substantial manufacturing and expenditure for material and supplies.

Appropriate is valid for from the GB 2,311,966 A admitted composite construction parts for vehicle bodies. Gemäß this state of the art one becomes äuß ere bowl and an internal bowl for the composite construction part by means of Spritzgieß EN from plastic manufactured and in a subsequent step by a Kunststoffschweiß procedure or with the help of adhesive along their edges firmly and closely connected. Then the developed hollow body is filled with a hardening filling from plastic. Alternatively to it also a filling material can be prefabricated, between that äuß eren and the internal bowl to insert is, if these are interconnected. For higher firmness requirements reinforcement parts made of aluminum are in the cavity between äuß to plan erer and internal bowl, whereby those äuß ere bowl with channels as the admission of the reinforcement parts is trained.

Schließ lich also roofs from composite material are admit (DE 32 02 594 C2), those from air and rainproof Auß enschicht, a middle, self-rigid honeycomb/structural layer with aluminum or sticking gene and/or semihard foam and fleece structures, a halfrigid, porous interior layer and a pad and/or a decoration layer by means of a Heiß preß procedure are manufactured.

The invention is the basis the task, in relation to the genericforming state of the art a simplified to make light however nevertheless sufficiently rigid composite construction part available for vehicle bodies whatever can be simply manufactured.

The task posed is solved by the characteristics indicated in the requirement 1. Favourable one and/or zweckmäß ige further educations come out from the Unteransprüchen 2 to 25 and are in the following likewise described.

Erfindungsgemäß is with a composite construction part for vehicle bodies, which a punched Auß enhaut and one the inside of the Auß enhaut up-foamed plastic film exhibits, which is provided with a textilen planar formation or a decorative plastic foil on their surface if necessary, the Auß provide enhaut at their edges frameless trained and with a circulating folding-up, whereby the foamed plastic film reaches up to the folding-up and in the foamed plastic film over the entire surface range of the Auß enhaut an actually not rigid reinforcing is intended, by which the modulus of elasticity of the foamed plastic film is increased.

By those erfindungsgemäß EN Maß took a composite construction part for vehicle bodies one creates, which gets along without complex additional profile elements for frameworks and props, nevertheless due to the cooperation of Auß enhaut and a becoming baggy rigidity and a total strength receives, which meet all requirements to the inherent stability of the composite construction part with all operating stresses of the vehicle to reinforced plastic film. Those erfindungsgemäß intended self-rigid reinforcing within the plastic film does not make an effective reinforcing for the plastic film possible into the boundary regions in special way of the Au&szlig trained with a circulating folding-up; enhaut inside.

As reinforcing not-self-rigid and/or bend-flabby fabrics, Gewirke, fleeces, lattice, mats come themselves u.dgl. out for example glass, plastic (e.g. polyester or Aramid) and/or carbon fibers into consideration, so far it the form of the Auß enhaut into their boundary regions inside adapt and by the up-foaming plastic in the closed foaming tool to be penetrated and coated can. Preferably become however gemäß Requirement of 2 fibrous materials for the education of reinforcing uses, which as fiber length sections in gleichmäß iger distribution, but in unordered situation of the plastic film are incorporated. Particularly good results became gemä&szlig by use of a reinforcing from glass fiber materials; Requirement 3 obtains, which are present in length sections of twisted glass fiber bundles of approximately 4800 tex between approx. 12.5 mm and approx. 100 mm of length. The modulus of elasticity of the foamed plastic, which exhibits a value of 300 N/mm2 without this reinforcing for instance, could be increased according to requirement 4 on bringing in a glass fiber reinforcing of 25 Gew,% related to the total weight of the reinforced mousse on over 1600 N/mm2.

The glass fiber materials can gemäß Requirement 5 in length sections of different length to be used, whereby by use of two different lengths with one größ eren portion of the smaller length - gemäß Requirement of 6 about two thirds of the glass fiber quantity - particularly good reinforcing results obtained are. In addition, in the context of the length paragraph region indicated in the requirement 3 to requirement 7 length sections of uniform length can be used.

For the Auß enhaut metallic materials are suitable such as Stahloder of aluminum plates. In addition, the use of a vacuum-punched Auß enhaut from a thermoplastic plastic foil, preferably a two-layered Koextrusionsfolie gemäß Requirement 8, results in a composite construction part of convincing stability. The Koextrusionsfolie consists favourably of the materials indicated in the requirement 9, i.e. PMMA for those äuß ere layer as well as a mixture from PC and ASP for the internal layer, and exhibits layer thickness conditions indicated there, according to which the thickness that äuß eren layer preferably about 15% of the total thickness of the Auß enhaut constitutes. For example the total thickness of the Koextrusionsfolie amounts to about 1.3 mm, about which about 0.2 mm on those äuß ere layer are void.

The use of a plastic foil offers also the advantage, daß gemäß Requirement 10 the plastic in the mass in the desired color through-colored to be can, so daß the composite construction part later not additionally to paint is. As au&szlig in the requirement 11 indicated the plastic foil can; erdem by use of a highly polished deep-drawing form on production of the dish-shaped Auß a shining surface enhaut or by preceding Kalandrieren a grained surface received.

If the Auß enhaut gemäß Requirement 12 formed out of a thin aluminum plate is verhältnismä&szlig, can its thickness owing to the reinforced plastic film in the interest of weight savings; industrial union small its, preferably approx. 0.6 mm. For the Auß particularly suitably the aluminum alloy AlMg 0.4 SI 1,2 indicated in the requirement 13 is enhaut.

In the case of use of an aluminum plate as material for the punched Auß enhaut the sheet metal before its hydraulic deep-drawing deformation can be provided in the desired color painted and with a protective plastic film, as in the requirement 14 indicated. During the deep-drawing deformation the film of varnish remains intact, as points oneself to taking the protective plastic film off. The structure of lacquer can be multilevel, in order to get over the deformation of the aluminum plate without tears or other damages. On a primary layer on epoxy resin basis from approximately 5 to 7 µm thickness can be laid on a finish coating on polyester basis from approximately 18 to 23 µm thickness, which again by a clear film of varnish from PVDF of 22 µm thickness can be covered. The burning temperature for a such multilevel structure of lacquer amounts to for instance 240°C. The hydraulic deep-drawing deformation of the finished painted aluminum plate can take place in several stages, for example three stages. Deep-drawing speeds of 60 mm/s proved as innocuous for the structure of lacquer.

To requirement 15 the folding-up of the Au&szlig goes; enhaut before deckle trim in one of it after auß EN bent circulating edge of flange over, whereby the reinforced plastic film at the folding-up is led along up to the edge of flange. The edge cutting of the composite construction part for example by contour milling or laser cut removes the bent circulating edge of flange and that äuß eren range of the folding-up of the Auß enhaut as well as the reinforced plastic film adhering at the ranges dropping thereby. An edge of folding-up of the Au&szlig substantial for the firmness remains after cutting; enhaut and the reinforced plastic film at the edge of folding-up receive. The edge cut is led both by the folding-up and by the reinforced plastic film, whereby a plane of section develops, which can be put on direct with training as vehicle roof on the roof frames present on the vehicle body.

The requirement 16 gives here a training variant for the circulating folding-up of the Auß enhaut on, gemäß that the folding-up in one of it after auß EN bent circulating edge of flange turns into, which with the Aufschäumen of the plastic film on the inside of the Auß enhaut a poetry over its entire width laminar fits, in order to seal between lower part and upper section of the sudsy form. With this training variant the above edge cutting is completely void after the sudsy procedure. Rather can already with the deep-drawing of the Auß enhaut or in a subsequent step after auß EN bent circulating edge of flange for the training of a defined Abschluß geometry of the Auß enhaut to be punched or fine-cut. The circulating edge of flange provides with the then following sudsy procedure under laminar plant at a poetry of the sudsy form favourably for a good and clean sealing of the sudsy form. It is in principle possible, daß the Auß enhaut before the sudsy procedure only a circulating folding-up exhibits, without one of it after auß EN bent edge of flange, which was if necessary already removed. However then the sealing of the sudsy form turns out more with difficulty, in particular can the sharp Abschluß edge the folding-up a negative Einfluß have on the service life of the poetry of the sudsy form.

After a particularly favourable arrangement of the composite construction part gemäß Requirement 17 is on the folding-up of the punched Auß enhaut a poetry attached, which exhibits two-donation leagues, essentially u-shaped cross section, whereby the internal thigh of the poetry is angeschäumt to the plastic film, during that äuß ere thighs the seals surface forms. In the result the composite construction part is after the Aufschäumen of the plastic film on the inside of the Auß enhaut in favourable way already with an integrated poetry provide, which opposite adjacent body construction units seals the composite construction part, without daß in addition further work procedures, for example the plug-on of an additional, first poetry which can be made available to the finished composite construction part necessary would be separated, which brings further cost savings with itself. This arrangement offers still the additional advantage, daß the poetry with the sudsy procedure between the lower part and the upper section of the sudsy form to seal can, as da&szlig in the requirement 18 indicated, so; here in the sudsy form no poetry to be planned muß , those by repetitive use verschleiß EN became.

The plastic film consists as indicated in the requirement 19 of a polyurethane foam, which is formed about 1 from a polyole and an isocyanate in the indicated mixing proportion, for i.e. to 2. The mixture of the two plastic components with the glass fiber reinforcing takes place in the well-known LFI procedure (Long fibre Injection).

The liquid plastic/glass fiber mass mixed in the mixture head becomes here on the punched Au&szlig inserted with their inside upward pointing into the lower part of the foaming tool; enhaut.etwa in their center beginning over a spiral way laid on, before that is brought to tool upper section in the intended thickness of the foamed plastic film appropriate position above the tool lower part. The finding foam fills the form and penetrates into the boundary regions of the Au&szlig which can be cut if necessary later; enhaut, anyhow up to the circulating folding-up of the Auß enhaut forwards.

Becomes a plastic foil as Auß enhaut used, the inside of the Au&szlig becomes; enhaut according to requirement 20 zweckmäß industrial union before laying the foamable plastic on for activation abgeflämmt, whereby an excellent connection of the Auß enhaut with the foamed plastic film one obtains.

If on the surface of the up-foamed plastic film a decorative planar formation is to be planned, this from the materials specified in the requirement 21 and becomes in the sudsy form on those the Au&szlig can be selected; if remote side of the plastic film enhaut applied, so daß it to a fixed connection between the up-foaming plastic film and the decorative planar formation comes. Zweckmäß industrial union is stretched, by this into the sudsy position is carried forward and remains here the decorative planar formation temporarily at the upper section of the foaming tool after the distance of the tool upper section on the plastic film.

In the case of use of a porous decorative planar formation is gemäß Requirement 22 intended, daß the planar formation in itself is multilevel developed, whereby the planar formation with one the plastic film course-turned barrier layer is provided, which prevents a piercing of the up-foaming plastic by the pores of the decorative planar formation in its range of vision inside.

The composite construction part can be provided in favourable way with the sudsy procedure with further functional elements. Thus turns the requirement 23 on a composite construction part for in particular a vehicle roof, its Au&szlig off; enhaut an opening exhibits, whereby on of the Auß enhaut remote side of the plastic film a guidance profile for the opening alternatively verschließ ends sliding cover is angeschäumt.

Gemäß Requirement 24 can further on of the Auß enhaut remote side of the plastic film with the sudsy procedure a sound-absorbing surface texture to be behind-foamed, whereby the sound isolation characteristics of the composite construction part for the training of e.g. hoods can be in a simple manner still improved. In place of or additionally to these macro geometry of the surface of the plastic film Ma&szlig concerned; took can schließ lich also the respective sound isolation requirements appropriate organization of micro geometry of the Auß enhaut turned away side of the composite construction part take place, as in the requirement 25 indicated, gemäß on of the Auß enhaut remote side of the plastic film are partially absorption ranges with decreased density of the foam material angeschäumt. This Anschäumen of the absorption ranges to the plastic film takes place zweckmäß industrial union in a second Schuß , i.e. after Aufschäumen of the plastic film on the inside of the Auß enhaut the absorption ranges in a subsequent step are angeschäumt to the plastic film.

In the following the invention is more near described on the basis preferential remark examples with reference to the attached design, whereby same indicators are assigned to the same and/or appropriate parts. In the design show:

Fig. 1

a broken off cut by the boundary region in a closed sudsy form vehicle fahrzeugdachs present gemäß a first remark example of the invention,

Fig. 2

a broken off cut by the boundary region finished vehicle fahrzeugdachs gemäß the first remark example,

Fig. 3

a broken off cut by the boundary region in a closed sudsy form vehicle fahrzeugdachs present before-prepared for a sun roof gemäß a second remark example of the invention,

Fig. 4

a broken off cut by the boundary region in a closed sudsy form vehicle fahrzeugdachs present gemäß a third remark example of the invention,

Fig. 5

a broken off cut by the boundary region in a closed sudsy form vehicle fahrzeugdachs present gemäß a fourth remark example of the invention,

Fig. 6

a broken off cut by the boundary region finished vehicle fahrzeugdachs gemäß the fourth remark example, which is installed at a roof frame,

Fig. 7

a schematic Perspektivansicht of one already at a passenger car body attached, erfindungsgemäß trained hood and

Fig. 8

a broken off cut of the hood according to the line A-A in Fig. 7.

Into the Fig. 1 and 2 is a punched Auß enhaut 1, one the inside of the Auß enhaut 1 up-foamed plastic film 2 and a decorative planar formation 3 present at the view side the vehicle fahrzeugdachs evidently. In Fig. 1 is upward turned the vehicle roof for the sudsy procedure with its inside, during in Fig. 2 the vehicle roof in his installed situation is represented. In Fig. 2 is schematically drawn in dash-dotted lines a roof frame 4 of a vehicle body and a lining 5 for the roof frame 4. The vehicle roof mount the roof frame 4 from above and is not connected with this in not represented well-known way.

The Auß enhaut 1 is at its edges, by which in the figures 1 and 2 representatively of the other edges only one edge is represented, with a circulating folding-up 6 provided, those with this remark example first for the production the vehicle fahrzeugdachs the one größ ere height (Fig. 1) exhibits as after the edge cutting (Fig. 2). As from Fig. 1 comes out, goes the circulating folding-up 6 into one of it to auß EN bent circulating edge of flange 7 over, which is removed here just like a substantial part of the folding-up 6 with the later edge cutting procedure, as results from a comparison of the figures 1 and 2.

In Fig. 1 represented sudsy form consists the punched Au&szlig of; enhaut 1 positively taking up lower part 8 and a complementary upper section 9, in whose boundary region an inflatable circulating poetry 10 is arranged, which provides for a delimitation the up-foaming plastic film 2 of the forming plastic. The decorative planar formation 3 is fastened in stretched form by means of a clamping frame 12 temporarily at the upper section 9 of the sudsy form used in a groove 11 of the upper section 9.

During the production the vehicle fahrzeugdachs becomes first the Auß enhaut 1 punched, in case of the use of a metal sheet metal material by multi-level hydraulic deep-drawing and in case of the use of a plastic foil by vacuum deep-drawing during appropriate setting of the edge of foil. In the latter case both sides to low-tighten of the plastic foil are warmed up by heating elements to for instance 180°C surface temperature. In such a way warmed up plastic foil is subjected to the vacuum deep-drawing procedure.

The punched preform of the Auß enhaut 1 after it with its inside pointing into the lower part 8 of the sudsy form represented in Fig.1 upward is inserted, on which the up-foamable plastic on those far way on the inside of the Au&szlig, indicated in front; enhaut 1 is applied. If it itself around a Auß enhaut from plastic foil, this acts can be activated before by Abflämmen. As foamed plastic for example a foam system of the company Elastogran is used, consisting of polyole B 237 and isocyanate E 3509, whereby these two components in the mixing proportion are used of 100 parts polyole to 210 parts isocyanate. After the order that is brought to the up-foamable plastic mass in the LFI procedure upper section 9 of the form with the planar formation 3 fastened to it in position, on which the up-foaming plastic loaded with glass fibers fills the entire free space of the sudsy form up to the top side of the edge of flange 7 and there limited by the blown up poetry 10.

For example 3.7 kg of the foamed plastic components with 1 kg of glass fibers are mixed, which corresponds to a glass portion in the foamed plastic of < 25 Gew,%.

In Fig. 3 vehicle roof in the sudsy form gemäß the second remark example is to be described in the following only regarding the characteristics differing from the first remark example.

Beside that äuß eren circulating folding-up 6 possesses with this remark example the Auß enhaut 1 also an internal circulating folding-up 13, which is bent in the same direction as the folding-up 6 and in the finished condition the vehicle fahrzeugdachs a Dachöffnung limited, which can be covered by means of a sliding cover not shown alternatively. As described reinforced plastic film 2 extends to the folding-ups 6 and 13 near, whereby the vehicle roof receives a sufficient rigidity.

Further is to be recognized, daß itself in the condition neither to the folding-up 6 nor to the folding-up, in the sudsy form, 13 after auß EN and/or inward bent edge of flange anschließ t. Here an inside takes place and äuß erer deckle trim of the Auß enhaut 1, with also after the deep-drawing procedure if necessary still existing edges of flange of the Auß enhaut 1 to be removed, before the Auß enhaut 1 into the lower part 8 of the sudsy form is inserted. Zweckmäß industrial union knows the folding-up 6 the Au&szlig inserted into the lower part 8 of the sudsy form; enhaut 1 slightly over the lower part 8 manages.

After inserting the Auß enhaut 1 into the lower part 8 of the sudsy form becomes an actually well-known, preferably from an aluminum alloy stranggepreß tes guidance profile 14, a which component of mechanics is for shifting the sliding cover, likewise inserted into the lower part 8 of the sudsy form. This concisely with the folding-up 13 abschließ end to guidance profile 14 limited in the represented closed condition of the sudsy form the cavity in the sudsy form, filling by the up-foaming plastic, whereby the guidance profile 14 with a thigh 15 between the lower part 8 is unverrückbar fixed and the upper section 9 of the sudsy form. In order to prevent, daß during the sudsy procedure the up-foaming plastic between the lower part 8 and the upper section 9 of the sudsy form, loaded with glass fibers, out and/or depresses, is out preferably EPDM existing seals 16 with suitable cross section at the ends of the folding-ups 6, 13 and at final sections 17, 18 of the guidance profile 14 in the lower part 8 and/or in the upper section 9 of the sudsy form intended. Schließ lich by suitable training of the upper section 9 of the sudsy form a groove 19 as well as a bearing surface 20 are produced as functional sections vehicle fahrzeugdachs with the sudsy procedure equal with. The groove 19 serves module-like vehicle fahrzeugdachs at the vehicle of the admission of an adhesive crawler-type vehicle when assembling, by means of which the vehicle roof is fastened to the vehicle-lateral roof frame, while the bearing surface 20 in the installed condition the vehicle fahrzeugdachs the roof frame defined rests upon.

In the finished condition the vehicle fahrzeugdachs is laminar at the plastic film 2 angeschäumt, so da&szlig the guidance profile 14; the guidance profile 14 is firmly connected with the vehicle roof, without daß further means of mounting would be necessary. Particularly to emphasize is here still, daß this for a sliding cover before-prepared vehicle roof due to its training with circulating folding-ups 6, 13 to the Auß enhaut themselves 1 and between them more extending as above described reinforced plastic film 2 completely without that while stationary the technology usual reinforcement framework gets along, which surrounds the Dachöffnung there and to conventional-proved the guidance profiles for the sliding cover is fastened.

In Fig. 4 third remark example shown differs from with reference to the Fig. 3 descriptive second remark example thereby, daß the folding-up 6 the Auß enhaut 1 in one of it after auß EN bent circulating edge of flange 21 turns into. Contrary to the first remark example gemäß Fig. 1 is so briefly trained, da&szlig the circulating edge of flange 21; it with the Aufschäumen of the reinforced plastic film 2 on the inside of the Auß enhaut 1 of the poetry 16 in the upper section 9 of the sudsy form over its entire width laminar fits. Since the edge of flange 21 rests upon thereby the lower part 8 of the sudsy form, it is pressed into the closed condition of the sudsy form into the poetry 16. In the result the sudsy form for the sudsy procedure between the lower part 8 and the upper section 9 is sealed reliably, without daß the danger exists, daß the folding-up 6 and/or the edge of flange 21 the poetry 16 damages. Also with this remark example a deckle trim of the Au&szlig takes place; enhaut 1 before this into the lower part 8 of the sudsy form is inserted. The deckle trim can at the same time with the deep-drawing of the Auß 1 enhaut or in a subsequent step in addition by stamping machines or precision cutting to be implemented.

With into the Fig. 5 and 6 represented fourth remark example is on the circulating folding-up 6 the Auß enhaut 1 a likewise rotating poetry 22 attached, the two-donation leagues, essentially u-shaped cross section exhibits. Gemäß Fig. 5 already the poetry 22 becomes with the Aufschäumen of the plastic film 2 on the Au&szlig already edge-cut; enhaut 1 also to the plastic film 2 angeschäumt, with their internal thigh 23, which extends however only over a part of the overall height of the folding-up 6, so that the reinforced plastic film can reach 2 also up to the folding-up 6. During the sudsy procedure the poetry favourably already serves 22 as sealing element between the lower part 8 and the upper section 9 of the sudsy form.

As in Fig. 6 to recognize is, forms that äuß ere thighs 24 of the poetry 22 in at the vehicle body installed the condition the vehicle fahrzeugdachs on the one hand a seals surface out, in order to seal between vehicle roof and roof frame 4. On the other hand that has äuß ere thighs 24 of the poetry 22 due to its elasticity the vehicle roof concerning the roof frame 4 centering effect. The poetry 22 consists in all other respects of a material, which can resist sufficiently in particular thermal and mechanical loads in the sudsy form and in at the vehicle installed the condition the vehicle fahrzeugdachs, e.g. foam rubber or EPDM. The Fig. 6 illustrates schließ lich still, as the vehicle roof is connected by means of an adhesive crawler-type vehicle 25 with the roof frame 4 of the vehicle body taken up in the groove 19.

It was already initially mentioned, daß vehicle roofs, but arbitrary surface ranges of vehicle bodies through as described developed composite construction parts to be trained cannot only. For it is exemplary in the Fig. 7 and 8 still another hood represented, their punched Auß enhaut 1 ' at its edges frameless trained and with a circulating folding-up 6 ' is provided, whereby on the inside of the Auß enhaut 1 ' up-foamed plastic film 2 ', in over the entire surface range of the Auß enhaut 1 ' an actually not rigid reinforcing is intended, up to which circulating folding-up 6 ' reaches.

Furthermore are in Fig. 8 Maß took represented, which still improve in particular the sound isolation characteristics of such composite construction parts. So can according to the groove 19 with reference to the Fig. 3 to 6 described remark examples, i.e. by appropriate training of the upper section of the sudsy form already with the Aufschäumen of the plastic film 2 ' on the inside of the Auß enhaut 1 ' on of the Auß enhaut 1 ' remote side of the plastic film 2 ' a sound-absorbing surface texture 26 ' to be behind-foamed, which exhibits a majority of parallel in the remark example represented here, slots 27 ' affecting the Schallreflexion. Likewise it is possible, to that side of the plastic film 2 ', which of the Auß enhaut 1 ' is remote, in a second Schuß partially absorption ranges 28 ' with decreased density of the polyurethane foam material anzuschäumen, whereby a porous and/or open-cellular microstructure of the surface can be obtained.

A composite construction part, in particular vehicle roof, is suggested, consisting of a punched Auß enhaut from Metallblech or plastic foil and one the inside of the Auß enhaut up-foamed plastic film. The plastic film possesses an internal reinforcing by it in gleichmäß iger distribution incorporated fibrous materials, preferably glass fiber materials, which the composite construction part in the cooperation with the Auß a substantial inherent stability and firmness enhaut lend. Substantially participates daß the fiber-reinforced plastic film also an edge folding-up of the Auß enhaut strengthens.