DEVICE FOR MANUFACTURING A COMPOSITE PART

Abstract

A mould for moulding materials, the mould comprising at least two corresponding mould elements (14, 16, 18, 20) moveable relative to one another towards and away from each other, the towards movement exerting pressure on a moulding material positioned within a cavity formed with the mould wherein upon the mould elements being in contact the mould cavity comprises a recess (120), the recess (120) being located beyond the edge of the moulding to allow escape of gas (12) during moulding.

Claims

1. A moulding system comprising a mould cavity containing a moulding material to be moulded under pressure, a recess provided at the edge of the moulding material to allow the escape of entrapped gas from within the mould cavity during moulding of the moulding material under pressure.

2. A moulding system according to claim 1, wherein the moulding material comprises a reinforcement part and a bonding part for bonding the reinforcement part to a substrate, the recess being provided at the edge of the bonding part to prevent air entrapment within or at the surface of the reinforcement part.

3. The moulding system according to claim 2, wherein the recess is only provided beyond the edge of the bonding part.

4. The moulding system according to claim 3 wherein the reinforcement part comprises at least one layer of a fibrous reinforcement material which is impregnated with a reinforcement resin material.

5. The moulding system according to claim 4 wherein the moulding material comprises a layer for bonding the moulding material to a metal layer.

6. The A-moulding system according to claim 5 wherein the moulding material comprises a preform comprising a serration or wavy lip extending at its edge beyond the extremity of the preform to permit flow of air into the recess formed by the serration or wavy lip and the cavity during moulding.

7. The moulding system according to claim 6 wherein the moulding material is contained within a cavity formed by mould elements and a metal layer.

8. The moulding system according to claim 7 wherein the mould is capable of being heated so that it can soften a thermoplastic material or cure a thermosetting material.

9. The mould for moulding materials for use in a system according to claim 1, the mould comprising at least two corresponding mould elements moveable relative to one another towards and away from each other, the towards movement exerting pressure on a moulding material positioned within a cavity formed with the mould wherein upon the mould elements being in contact the mould cavity comprises a recess, the recess being located beyond the edge of the moulding material to allow escape of gas during moulding.

10. A moulding material for use in a mould according to claim 9, wherein the moulding material comprises a prepreg wherein the preform is shaped to provide one or more channels at its edges to provide one or more recesses to allow the escape of air beyond the extremity of the preform during moulding.

11. (canceled)

12. (canceled)

13. (canceled)

14. (canceled)

15. (canceled)

16. A mould for moulding materials, the mould comprising at least two corresponding mould elements moveable relative to one another towards and away from each other, the towards movement exerting pressure on a moulding material positioned within a cavity formed within the mould, wherein upon the mould elements being in contact the mould cavity comprises a recess, the recess being located beyond the edge of the moulding material to allow escape of gas during moulding.

Description

[0044] The invention is illustrated by reference to the accompanying drawings in which

[0045] FIG. 1 shows a diagrammatic view of a first moulding process and

[0046] FIG. 2 shows a diagrammatic view of a moulding process according to an embodiment of the present invention.

[0047] FIG. 3 shows a cured preform comprising no serrations (a) and a preform comprising serrations (b) according to embodiments of the invention.

[0048] FIG. 1 shows part of a conventional moulding system (10) comprising a mould cavity formed by mould elements (14, 16, 18, 20) containing a moulding material (carbon fiber reinforced plastic, CFRP) being moulded under pressure. Mould element (18) is a metal layer. The cavity is enclosed when the mould is closed and all elements (14, 16, 18, 20) have moved towards one another so that upon the application of pressure and heat causing the resin in the moulding material to flow and cure filling any cavities in the mould cavity with resin and gas (12) in the form of air is entrapped in the cured moulding material (FIG. 1 and FIG. 3(a)). This reduces the mechanical performance (tensile strength and interlaminar shear strength) of the cured moulding material.

[0049] FIG. 2 shows part of a moulding system (100) according to the invention which comprises a mould cavity containing a moulding material (CFRP) being moulded under pressure, a recess being provided at the edge of the moulding material (CFRP) to allow the escape of entrapped gas from within the mould cavity. In this way entrapped gas in the form can escape the closed cavity

[0050] The mould in FIG. 2 comprises corresponding mould elements (140, 160, 180, 200) moveable relative to one another towards and away from each other, the towards movement exerting pressure on a moulding material (CFRP) positioned within a cavity formed with the mould wherein upon the mould elements (140, 160, 180, 200) being in contact the mould cavity comprises a recess (120), the recess (120) being located beyond the edge of the moulding to allow escape of gas during moulding.

[0051] FIG. 3(a) shows a conventional moulding material which has a straight edge. This material is used in the moulding system as shown in FIG. 1. FIG. 3(b) shows a moulding material according to the invention. This moulding material comprises a preform of a preformed thermosetting material wherein the preform is shaped to provide one or more channels at its edges to provide one or more recesses to allow the escape of gas beyond the extremity of the preform during moulding. The channels are in the form of a serration.