GB2216062A

GB2216062A - Moulding

Info

Publication number: GB2216062A
Application number: GB8902794A
Authority: GB
Inventors: John Casey
Original assignee: HP Chemie Pelzer Research and Development Ltd
Current assignee: HP Chemie Pelzer Research and Development Ltd
Priority date: 1988-02-17
Filing date: 1989-02-08
Publication date: 1989-10-04
Anticipated expiration: 2009-02-08
Also published as: KR920001559B1; IE880433L; IE60537B1; KR890012777A; FR2627127B1; DE3903471B4; ES2014577A6; GB2216062B; DE3903471A1; FR2627127A1; GB8902794D0

Description

2216062 MOULDING The invention relates to a moulding, especially for

building into motor vehicles, for example as a door panel, parcel tray, engine bonnet, engine shield or the like, and a method for the manufacture of said moulding.

In the state of the art, mouldings of, for example, polyurethane foam are known, and are used as panel (cladding) elements. Such mouldings must exhibit relative dimensional stability in order to maintain the desired contours and the desired position in use. When using such mouldings the inclusion of an additional constructional element as a sound absorber is often necessary.

Based on this state of the art, the object of the invention is to create a moulding of this type which on the one hand is self-supporting and freely mouldable, and on the other hand permits of combination in a very simple manner with a sound- absorbing layer,. especially in a single operational s t e p For the solution of this problem the invention provides that the moulding consists of a self-supporting, preformed and compressed component which is joined on at least one side to a non- rigid component.

2' It is preferably provided that the self-support-ing component consists of at least one of the followinq materials: phenolic resin-impregnated non- woven fabric, hard plasticsimpregnated non-woven fabric, particularly non- woven cotton _fabric, non-woven synthetic fabric, polyurethane reinforced' with glass fibre.

In addition it is preferably provided that the non-rigid component consists of at least one of the following materials: fibrous material, non-woven fabric, polyurethane foam.

The moulding in accordance with the invention is characterized in that on the one hand it comprises a selfsupporting, preformed and compressed component, which component can be formed so that it can have a genuine supporting function. On the other hand however, this moulding additionally comprises a non-riqid component wbich can serve as a sound absorber. Of course the moulding can consist also of a number of self- supporting components and a number of non-rigid components.

The moulding in accordance with the invention can be used as a selfsupporting insulating or absorbing element. Thus, for example, complete door panels, parcel trays or the like inner fittings can be constructed as a mou.1ding in accordance with the invention. It is also possible to form body parts, for example the engine bonnet or- an eng.ine shield, in a manner in accordance with the invention.

Depending on the material used for the self-supporting component, the self-supporting component may be soundtransmitting, so that the non-rigid component may better exhibit its sound-absorbing effect. It is also preferably provided that a gas-impermeable layer is disposed between the facing surfaces of the self- supporting and the nonrigid component.

In particular it is provided that the gas-impermeable layer consists of a synthetic film, especially a polypropylene film or a polyetheylene film.

On the one hand the film constitutes a means which can advantageously be used for the production of the moulding, and on the other hand the film acts as the binding agent between the non-rigid and the self-supporting components if the film is sufficiently heated during the production process so that it can enter into fused bonds with the surrounding materials.

In addition it may be provided that the gas-impermeable layer is an acoustically effective dense layer made of at least one of the following components: thermoplastic synthetics with fillers, hard plastics, polyurethanes, casting resin, mixtures of at least two of these components.

This arrangement allows a so-called resilient mass system to be incorporated in the self-supporting moulding, so that as well as sound absorption, a soundinsulating effect can be achieved. The acoustically effective dense layer is thereby integrated with varying thickness, usinq suitable concentration of mass at acoustically determined points.

A preferred method for the production of mouldings of the above type is provided in accordance with the-inventJon in that the air-permeable, unmoulded material for forming the self- supporting component is placed onto a surface of a mould which corresponds with the contours of the moulding to be produced, this material is covered on one side by a qasand air-impermeable layer or film, also that the non-rigid, air-permeable component is placed onto this layer or film, the layered body thus formed is heated to a temperature which allows thermoplastic or hard plastics (thermosetting) deformation and the heated layered body is compressed against the contoured mould surface by the effect of air or gas excess or reduced pressure.

It is possible, for example, to first place a layer of a s-elf-supporting material as specified above onto the relief surface of the mould, to cover this layer with a synthetic film as specified above and to apply a layer of material as specified above for the non-rigid component onto this film.

The entire layered material can be heated by for example infra-red heating, so that the deformable thermoplastic or thermosetting components soften, whereupon the entire layer is pressed against the contoured surface of the mould by, for example, compressed air- As a result of the fact that the air-impermeable layer or is film prevents the penetration of the air into that component which later serves as the self-supporting compone.nt, this layer is firmly compressed according to the air pressure used, in contrast to the non- rigid component layer which forms the sound absorbing member, which layer is permeated by the compressed air without being compressed or crushed. Simultaneous cooling of the material pack is achieved by the relatively cool compressed air which is set for example at room temperature, so that after a relatively short period of application of the compressed air, t-he self-supporting component receives a permanent contour corresponding to the contoured surface of the mould- The layer forming the non-riqid component is thu-s fitted to the contour of the dimensionally stable self-supportinq moulding in a very precise manner.

Of course it is also possible to create a vacuum inside the mould, instead of using compressed air, so that that part of the layered pack which later forms the self-supporting moulded component is sucked against the correspond.i.n.q_ contoured surface of the moulding tool, which is of prime advantage in cases where a particular thickness of the layer which forms the dimensionally stable self-supportina component part is required.

A-further development of the invention provides that several layers of material for forming the self-supporting component are alternated with layers of non-riqid com ponents with interposition of air-impermeable layers or films and that the pressurizing effect of increased or reduced air or gas pressure is applied around the layers of material for forming the self-supportinq component. In order to achieve the desired form of the individual components in a multi-layered construction, it is only necessary to ensure that no air-per-meable Joint exists is between the individual layers, so that the vacuum or the excess pressure used in the individual layers is only effective where it is required for the formation of the self-supporting, preformed and compressed component. This is most simply achieved in that, for example, the compress ion or suction lines are disposed so that they open into the reauired layer, while the ends of the lines are each screened off from layers forminq the non-riqid components by air-impermeable films or the like.

As there are cases where acoustic considerations may render unsuitable the application of the air-impermeable film, provision may also be made for melting open the air impermeable film after the layer. for forminq-the se If supporting component has been moulded. Thus by the suitable application of heat the film can be in.effect completely removed by melting it open and using it as an adhesive between the neighbouring layers of material.

Depending on the consistency and thickness of the film, the heat for melting the film may be applied during the compression moulding of the self-supportinq component, or the heat maybe applied stjhsptltjpntly, after the formation of the pref nrined, coinr)re<, sed s p] f -support i n(l component.

Alternatively, or in addition it may be provided that an adhesive, especially a fusion adhesive, is introd-uced between the layers.

The gas-impermeable layer required for this technique may also be formed as an acoustically effective dense layer consisting of thermoplastic synthetics with fillers, hard or thermosetting plastics, polyurethanes, casting resins, or mixtures of two or more of these components- It is also advantageous to adjust the layer thickness of the material which is moulded and compressed by air pressure, by suitably regulating the air pressure, whether excess or reduced.

In principle it is also possible to use the method in accordance with the invention to produce a moulding which simply consists of a self-supporting, preformed and compressed component and which is not joined to a non-rigid component. Such self-supporting mouldings of the materials as described above are also useful and of advantage when fitted in motor vehicles, for example as body parts- Us i nq the multi-layered construction in accordance with the invention it is possible to produce a multi-layered moulding of suitable constitution in a single step, which results in a considerable saving in energy and time. Of course, it is also possible to incorporate panelling, metal parts or other preformed parts into the composite structure simultaneously with the process for production of the moulding. In this case adhesive, especially fusion adhesive, may additionally be applied between the outer layer and the panelling member to be joined thereto- An additional film may also be used as binding means, which film is intended to melt under suitable application of h e a t.

In the drawinqs the contruction and production process nf the mouldinq are schematically shown.

-.7 - Figure 1 shows a cross-section of a mould for poducing a moulding; Figure 2 shows a multi-layered moulding before it is compressed.

The moulding in accordance with Figure 1 for use in motor vehicles, for example as a door panel, parcel tray, engine bonnet, engine shield or the like constructional element, essentially comprises a self-supporting preformed and compressed component 1, joined on one side to a non-rigid component 2. The self-supporting component can for example be of phenolic resin-impregnated non-woven fabric, hard plastics-impregnated non-woven fabric, especially non-woven cotton fabric, non-woven synthetic fabric, or also of polyurethane reinforced with glass fibre. The non-rigid component 2 is preferably of fibrous material, non-woven fabric or polyurethane foam. For the design in accordance with the invention, and for this industrial process, it is a necessary condition that the non- rigid component 2 be air-permeable. Between the self-supporting component 1 and the non-rigid component 2 a gas-impermeable layer, especially an airimpermeable layer, is disposed which is formed by a synthetic film 3. Possible materials for this synthetic film are for example polypropylene or polyethylene.

In order to produce a moulding, as essentially shown in its final state in Figure 1, it is only necessary to sh ' ape and contour the mould half 4 of the moulding tool, which consists of mould halves 4 and 5, to correspond-with the shape of the final mouldinq. The tipper mould half 5 can be arbitrarily contoured, as this is of no import whatsoever for the shaping of the moulding. it is only of importance, that a space is created within the two mould halves 4 and 5, which in the exemplary embodiment is provided with a compressed-air supply 6. Via the compressed-air supply 6 35 compressed air, beginning in the range of, for example, 0.5 bar up to 1.5 bar, is introduced into the mould, for which the mould need not be sealed, but the compressed air can and should be allowed to escape through the mould seam between the mould halves 4 and 5, since the circulating air is simultaneously used as a cooling medium. At the beginning of the manufacturing procedure for forming a moulding of this type, the individual layers are laid into the mould as is shown, for example, in Figure 2 in a strictly schematic way.

Subsequently the mould is closed and compressed air in the given range is fed through the connections 6. Under the action of the compressed air which permeates the non-rigid component 2, the film 3 is pressed against the layer of material which later forms the component I and thus this layer of material is compressed against the contoured surface in the lower mould half 4 and is permanently shaped. Preceeding this moulding phase there is a heating phase which serves to heat the various layers of materia.ls to the temperature required for bonding the materials.

After the compressed air has acted for a sufficient period, the moulding has achieved the desired shape and can be removed from the mould after this has been opened. While the moulding is still in the mould, it is also possible, if required, to destroy, or indeed to decompose the film 3 by the application of heat, whereby the film itself can act as an adhesive between the layers 1 and 2.

Instead of the compressed air which, in the exemplar.y embodiment, acts from above, it is of course also possible to provide a connection port below the layer 1 f-or a suction-producing apparatus, so that the layer 1 is sucked against the contoured surface of the lower mould half in such a manner that the film 3 is pulled down by suction. By suitable adjustment of the reduced pressure, the thickness of the layer 1 can be adjusted. (Expressions such as "up", "down" etc refer to Figure 1 of the drawings).

9 In Figure 2 an exemplary embodiment is shown in which several layers of the material used to form the selfsupporting component are alternated with layers of nonrigid components 2, and an air-impermeable film 3 is 05 disposed between each pair of layers 1 and 2.

As either connecting ports 6 for connecting compressed air supplies or connecting ports 7 for connecting suction lines extend into the individual layers, It is possible to shape these layers as seen in and described with reference to Figure 1.

The air impermeable films 3 are the precondition for achieving the required moulding function- Of course it is also possibly to simultaneously supply increased and reduced pressure via the connection ports 6 and 7 is respectively.

The invention is not restricted to the exemplary embodiment, but may be widely varied within the scope of the disclosure.

All new features, singly or in combination disclosed in the description and or drawings are to be understood as essential features of the invention.

m h - 10

Claims

C 1 a i m s

1. A moulding, especially for building into motor vehicles, for example as a door panel, parcel tray, engine bonnet, engine shield or the like, characterized in that the moulding consists of a self-supporting, preformed and compressed component,particularly one which is joined on. at least one side to a non- rigid component.

2. A moulding according to claim 1, characterized in that the selfsupportinq component consists of at least one of the following materials: phenolic resin-impregnated non-woven fabric, hard plastics-impreqnated non-woven fabric, in particular non-woven cotton fabric, non-woven synthetic fabric, polyurethane reinforced with glass f i bres

3. A moulding according to one of claims 1 or 2, characterized in that the non-rigid component consists of at least one of the following materials: fibrous material, non woven fabric, polyurethane foam.

4. A moulding according to one of claims 1 to 3, charac- terized in that a gas-impermeable layer is disposed between the facing surfaces of the self-supporting and the non rigid component.

5. A moulding according to one of claims 1 to 4, characterized in that the gas-impermeable layer consists of a synthetic film, particularly a polypropylene film or a polyethylene film.

6. A moulding according to one of claims 1 to 5 characterized in that the gas-impermeable layer is an acoustically effective dense layer of at least one of the followinq components: thermoplastic synthetics with fillers, hard or thermosetting plastics, polyurethanes, casting resins, mixtures of at least two of these components.

7. A method for the production of mouldings according to one of claims 1 to 6, characterized in that the airpermeable, unshaped material for forming the selfsupporting component is laid onto a surface of a mould which corresponds to the contour of the moulding to be produced, that this material is covered on one side wit.h a gas- and air-impermeable layer or film, that the non-rigid, air-permeable component is applie d in particular to this layer or film, that the layered body thus formed is heated to a temperature which allows thermoplastic or thermosetting moulding and that the heated layered body is pressed against the contoured mould surface by the effect of excess or reduced pressure from air or gas.

8. A method according to claim 7, characterized in that several layers of material for forming the self-sup-portinq component are alternately layered with layers of non-rigid components with interposition of air-impermeable layers or films and that increased or reduced pressure of air or gas is applied locally at the layers of material for forming the self-supporting components.

9 h.

9. A method according to claim 7 or 8, characterized in 1 that the air-impermeable film is melted open after the layer for forming the self-supporting component has been moulded.

10. A method according to claims 7 to 9, characterized in that adhesive, especially fusion adhesive, is applied between the layers.

11. A method according to claims 7 to 10, characterized in that the thickness of the layer of material which is moulded and compressed by means of air pressure is regulated by correspondingly gauging the (increased or reduced) air pressure.

12. A method for the production of mouldings, substantially as herein described with reference to or as illus trated in the accompanying drawings.

13. A moulding whdnever produced by a method claimed in a preceding claim.

14. A moulding substantially as herein described with reference to or as illustrated in the accompanyina drawings.

Published 19a9 atThe Patent Ofnoe, State House, 88.71 High Holborn, London WClR 4TP. Further copies maybe obtaJnad from The Patent O:Moe Sales Branch, St Mary Cray, Orpington, Kent BRS 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1/87