WO2014082115A1

WO2014082115A1 - Edge arrangement for a composite wheel

Info

Publication number: WO2014082115A1
Application number: PCT/AU2013/000647
Authority: WO
Inventors: Matthew Edward DINGLE; Ashley James Denmead; Michael Silcock; Aaron Brighton; Haydn Law
Original assignee: Carbon Revolution Pty Ltd
Priority date: 2012-11-30
Filing date: 2013-06-17
Publication date: 2014-06-05

Abstract

A rim component (102) of a composite wheel (100) comprising a rim body (118) formed around a central axis (X-X), the rim body (118) axially extending between two annular edges (120), the rim body (118) comprising: a plurality of layers (126) of reinforcement fibres, at least one of the layers (126) having an end (128) which extends to at least one of the annular edges (129); and at least one substantially continuous capping layer (132) comprised of reinforcement fibres wrapped over and around the respective ends of the layers (126) of at least one of the annular edges (129) of the rim body (118).

Description

EDGE ARRANGEMENT FOR A COMPOSITE WHEEL TECHNICAL FIELD

[0001 ] The present invention generally relates to a rim component of a composite wheel and an edge arrangement thereof. The invention is particularly applicable to composite carbon fibre wheels for vehicles and/or aeroplanes and it will be convenient to hereinafter disclose the invention in relation to that exemplary application. However, it is to be appreciated that the invention is not limited to that application and could be incorporated into the rim configuration of a large variety of wheels.

BACKGROUND OF THE INVENTION

[0002] The following discussion of the background to the invention is intended to facilitate an understanding of the invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was published, known or part of the common general knowledge as at the priority date of the application.

[0003] The Applicant has produced a one-piece composite wheel, which is described, for example, in International Patent Publication WO2010/024495A1 .

[0004] The Applicant's composite wheel generally includes two main sections, a rim portion and a face portion. The rim portion comprises an annulus structure configured to receive and seat a tyre. The face portion includes a hub which is used to fix the wheel to the vehicle, and a connection structure such as series of spokes or a disc which extends between and interconnects the hub and the rim. Lateral, vertical and torsional loads are transmitted through the tyre to the rim portion of the wheel which then produce bending and torsional stresses in the connection structure.

[0005] The creation of a one-piece composite wheel generally necessitates use of a separate rim portion mold and associated reinforcement and face portion mold and associated reinforcement. The separate rim and face mold portions are then interconnected in a final molding process which allows the overall composite wheel to be integrally formed.

[0006] The rim portion of a composite wheel typically comprises a generally cylindrically shaped rim body having two flanged annular edges, each flange having an outside surface including an annular bead located at the edge. The reinforcement of the rim portion is conventionally laid up as stacked layers of reinforcement fabric in the rim body, the flanged edges and the annular bead. The layered structure typically terminates with the ends of the layers extending from a section of the flanged edges. The stacked structure of the layer ends at the flanged edges can therefore have a rough and uneven finish. Consequently, it has been standard practice to machine the composite rim structure at the edge of the inner bead after removing the part from the mold tool to provide a more even finish.

[0007] However, machining a composite structure cuts the reinforcement fibres and exposes the cut fibre ends at an external surface of the part. Minor areas of delamination between reinforcement layers may also be produced by the machining process. These cut fibres and any minor delamination at the cut edge can create small crack initiation sites in the composite body. During severe vehicle usage, for example when driving on rough roads or impact with depressions or obstructions, these cracks may grow and can ultimately result in the failure of the composite wheel.

[0008] It would therefore be desirable to provide an improved or alternate edge arrangement for the rim portion of a composite wheel.

SUMMARY OF THE INVENTION

[0009] The present invention provides in a first aspect, a rim component of a composite wheel comprising a rim body formed around a central axis, the rim body axially extending between two annular edges, the rim body comprising: a plurality of layers of reinforcement fibres, at least one of the layers having an end which extends to at least one of the annular edges; and at least one substantially continuous capping layer comprised of reinforcement fibres wrapped over and around the respective ends of the layers of at least one of the annular edges of the rim body.

[0010] The present invention therefore provides a rim component of a composite wheel where the annular edges including the exposed ends of the layers of reinforcement fibres are covered by a layer of reinforcement. This arrangement results in that edge being molded to the final shape of that annular edge after a matrix material, such as resin is impregnated/ introduced into the component. No subsequent machining of the reinforcement is therefore necessary to provide an acceptable finish.

[001 1 ] It is important that the capping layer provides a substantially continuous cover over the respective annular edge and the exposed ends of all internal fibre reinforcement layers, so that no fibre ends are exposed. The continuous cover also ensures a molded surface is produced once the matrix material is introduced, so that subsequent machining processing is not required. It is noted that any advantages provided by the present invention would be negated if subsequent machining processing is used on that annular edge, as this would involve cutting fibres at this location thus exposing cut fibres or creating delamination between fibre layers in the rim.

[0012] The rim component of the present invention could comprise a rim portion of a integrally formed composite wheel, a wheel-rim preform or precursor, or a separate a rim component which can be interconnected with a separate wheel disc and hub component (metal spokes or similar), for example as described in United States Patent No. 7,918,513 B2.

[0013] It should be understood that the term composite herein denotes any type of composite material comprising fibres, cured or uncured, irrespective of the structure being layered or not. Furthermore, pre-forms and pre-consolidated pre-forms cured or uncured are important subgroups of composite materials and bodies. [0014] The rim body preferably comprises a generally cylindrically shaped body. In some embodiments, the rim body includes at least one flange at or proximate the annular edge thereof, preferably forming two flanged annular edges. The rim body typically has an outside annular surface and an inside annular surface extending between the annular edges. In some embodiments, the capping layer extends over at least a portion of the inside annular surface and the outside surface of the rim body.

[0015] In some embodiments, the rim body, and/or in applicable embodiments, the flanged annular edges, can include at least one first annular bead located at or proximate at least one annular edge. The capping layer preferably extends over the first annular bead. In some embodiments, the rim body includes at least one second annular bead axially spaced apart from the first annular bead, the capping layer extending at least to the second annular bead. The first and second annular beads are preferably located on the outside annular surface of the rim body.

[0016] The rim portion is laid out with a layered structure. The number of layers may vary considerably depending on the design and size of the various sections of the rim component. In some embodiments, only a few layers, for example 2, 3, 4, 6 or 10 are used. In other embodiments, a higher number of layers, for example 20, 30, 50, 100 or more are needed to obtain the desired quality and/or properties of the rim component. The layer structure preferably comprises a plurality of stacked layers. Within each layer of the layer structure preferably comprises a substantially coplanar arrangement of reinforcement fibres.

[0017] A wide variety of fibres may be used in the present invention, including but not limited to fibres selected from the group consisting of carbon fibres, glass fibres, aramid fibres, synthetic fibres such as acrylic, polyester, PAN, PET, PE, PP or PBO-fibres, or the like, bio fibres such as hemp, jute, cellulose fibres, or the like, mineral fibres for example Rockwool or the like, metal fibres for example steel, aluminium, brass, copper, or the like, boron fibres or any combination of these. In a preferred embodiment, the reinforcing fibres of the rim body and/or capping layer comprise carbon fibres. [0018] The reinforcement fibres may be provided in any desirable orientation in the rim body and capping layer, including but not limited to unidirectional, biaxial or random. Each reinforcement layer in the body portion preferably comprises oriented reinforcement fibres, preferably unidirectional fibres or biaxial reinforcement fibres. The capping layer also preferably comprises oriented reinforcement fibres, preferably unidirectional fibres or biaxial reinforcement fibres. It should be noted that the orientation of the reinforcement fibres in the capping layer may be the same, or different to the orientation of the reinforcement fibres in the body portion.

[0019] In some embodiments, the reinforcement fibres are preferably oriented to reduce the stress with the rim component and/or reduce the stress between the rim component and any connected component (such as the disc portion of a composite wheel) as well as to strengthen areas of the final structure which will be exposed to a higher stress during service. The orientation of reinforcement fibres may or may not be the same in all the layers of the body portion. For example, one or more layers of reinforcement fibres may be oriented in another manner than other layers, if a stress analysis suggests a multi-axial fibre orientation. However, in other embodiments the reinforcement fibres may be oriented substantially the same way in all the layers of the body portion of the rim component.

[0020] The reinforcement fibres may be provided in any suitable form including in prepregs, semi-pregs, woven or non-woven fabrics, mats, pre-forms, pre- consolidated pre-forms, individual or groups of fibres, tows, tow-pregs, or the like. During lay-up (preparing up to the point before consolidation and/or curing of the matrix material) of the rim component, the matrix material, such as resin, need not be comprised in the layers comprising reinforcement fibres (e.g. a prepreg or semi-preg) or between the layers comprising reinforcement fibres. However, the matrix material should form a continuous matrix after the curing.

[0021 ] The matrix material need not be comprised in or between two adjacent layers com- prising reinforcement fibres. In a preferred embodiment an adhesive may in this case be provided between at least some of such pairs of layers to at least temporarily and at least partially fix the adjacent layers comprising reinforcement fibres.

[0022] It is to be understood that prepreg refers to a substantially or fully impregnated collection of fibres, fibre tows, woven or non-woven fabric or the like. Similarly, it is to be understood that semi-preg refers to a partially impregnated collection of fibres or fibre tows. The partial impregnation provides for enhanced removal of gas through or along the dry fibres during consolidation and/or curing. An example of a semi-preg is a partially impregnated layer of fibres.

[0023] It is to be understood that woven and non-woven fabrics are collections of individual fibres or fibre tows which are substantially dry, i.e. not impregnated by a matrix material, for example resin. It should also be understood that fibre tows are bundles of a large number of individual fibres, for example 1000's, 10000's or 100000's of fibres. Tow-pregs are at least partially impregnated fibre tows.

[0024] Sections of the rim component may be prepared as a pre-form. In such an embodiment, one or more of the sections of the rim component are formed into a tailored fibre preform having a desired shape and fibre orientation. It is to be understood that a pre-form is a composite material comprising reinforcement fibres, and typically, an uncured resin. The reinforcement fibres are preferably provided in layers of oriented fibres, for example individual or groups of fibres, fibre tows, fibre tow-pregs, prepregs, semi-pregs, woven or non-woven fabrics or mats. In preferred embodiments, the reinforcement fibres of the rim body and/or the capping layer are provided as at least one fabric sheet or ply, and more preferably as at least one multi-axial fabric sheet or ply. Where applicable, the first and/or second annular beads may include a preform such as at least one fibre tow, fibre tow-preg, uni-tow or similar.

[0025] The fibres of the rim component are preferably injected and/or impregnated with a matrix material which is allowed to set/cure. In some embodiments, the matrix material comprises a resin. In this embodiment, the fibres of the rim component are preferably injected and/or impregnated with resin and then cured. The rim component therefore preferably further comprises a resin enveloping the reinforcement fibres. Any suitable resin can be used. The resin is preferably based on unsaturated polyester, polyurethane, polyvinyl ester, epoxy, thermoplastics, similar chemical compounds or combinations thereof. In a preferred embodiment, the resin is epoxy-based. In other embodiments, the matrix material comprises a metal or composite metal material. In these embodiments, the fibres of the rim component are preferably injected and/or impregnated with a metal or metals, forming a composite metal matrix with the fibres when set. The metal matrix material is preferably selected from aluminium, magnesium, titanium, iron and combinations, alloys and mixtures thereof.

[0026] A second aspect of the present invention provides a method of forming a rim component of a composite wheel, the rim component comprising a rim body formed around a central axis, the rim body axially extending between two annular edges, the method comprising the steps of:

providing a plurality of layers of reinforcement fibres to form the rim body of the rim component, at least one of the layers having an end which extends to at least one of the annular edges;

providing at least one substantially continuous capping layer comprised of reinforcement fibres wrapped over and around the respective ends of the layers of at least one of the annular edges of the rim body.

[0027] The method of forming a rim component of a composite wheel according to the second aspect preferably forms a rim component according to the first aspect of the present invention.

[0028] In some embodiments, the rim body has an outside annular surface and an inside annular surface extending between the annular edges, and wherein each capping layer comprises a layer of fabric reinforcement which is wrapped around the respective annular edge from the outside annular surface to overlap onto the inside surface of the rim body; or wrapped around the respective annular edge from the inside annular surface to overlap onto the outside annular surface of the rim body.

[0029] In some embodiments, the method of the second aspect may further include the steps of:

providing a matrix material, preferably resin in contact with each of the layers of the rim component; and

curing the rim component.

[0030] It should be appreciated that curing encompasses setting, drying, curing processes relevant to the specific matrix material used.

[0031 ] Where the matrix material is a resin, a variety of resin delivery systems can be used with the method of the second aspect. In some embodiments, at least a part of the resin is provided by Resin Infusion and/or Resin Transfer Molding and/or Vacuum Assisted Resin Transfer Molding.

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The present invention will now be described with reference to the figures of the accompanying drawings, which illustrate particular preferred embodiments of the present invention, wherein:

[0033] Figure 1 is a front perspective view of a composite wheel including a rim component having an edge arrangement according to one embodiment of the present invention.

[0034] Figure 2 is a rear perspective view of the composite wheel shown in Figure 1 illustrating one beaded annular edge of a rim component thereof including an edge arrangement according to one embodiment of the present invention.

[0035] Figures 3A and 3B provide schematic representations of one embodiment of the structural reinforcement components of the edge of the rim portion of the composite wheel shown in Figures 1 and 2. DETAILED DESCRIPTION

[0036] Referring firstly to Figure 1 , there is shown a perspective view of a composite wheel 100 which includes a rim component or portion 102 according to the present invention. The illustrated composite wheel 100 has been developed by the Applicant as being formed as a one-piece body. The general process of manufacture of the composite wheel 100 is described in International Patent Publication WO2010/024495A1 , the contents of which are to be understood to be incorporated into this specification by this reference.

[0037] The illustrated composite wheel 100 includes two main sections:

A) . a rim portion 102 comprises an substantially cylindrically shaped structure onto which a tyre (not illustrated) is mounted; and

B) . a face portion 104 comprising a circular hub 106 and a series of spokes 108.

[0038] The hub 106 includes five fastening apertures 107 configured to received fastening bolts (not illustrated) used fix the wheel to a wheel mount of a vehicle (not illustrated). The spokes 108 comprise elongate arms connected to the hub 106 at one end and the rim portion 102 at another end.

[0039] As described in International Patent Publication WO2010/024495A1 , the creation of such a one-piece composite wheel 100 necessitates use of a separate rim portion mold (not illustrated) and face portion mold (not illustrated). In use, the rim portion 102 is formed by laying up a first set of fibres, typically embodied in a reinforcement fabric seated in the rim portion mold. The face portion 104 is formed by separately laying up a second set of fibres, typically embodied in a reinforcement fabric seated in the face portion mold. The reinforcement fabric from the rim portion mold and face portion mold are then assembled together in a combined mold, with the separate portions being interconnected at a connection point 1 10. A final molding process is then undertaken in which a matrix material, in this case a resin, can be injected and/or infused into the reinforcement of the overall wheel form to produce a molded single piece wheel 100.

[0040] Figure 2 provides a better view of the configuration of the rim portion 102 of the composite wheel 100. The rim portion 102 generally comprises a generally cylindrically shaped rim body 1 18 having two flanged annular edges 120. The rim portion 102 has an outside annular surface 124, against which a tyre is mounted, and an inside annular surface 125 defining an opening through which the axle of a vehicle is received. Each flange 120 includes a first annular bead 122 located at each edge 129 and extending from the outside surface 124 of the rim portion 102.

[0041 ] A more detailed cross-sectional view of the flange 120 section of the rim portion 102 of the composite wheel 100 is shown in Figures 3A and 3B. The cross-section illustrates that the flange 120 comprises a stacked layered structure of reinforcement fibres layers 126 set within a matrix material, in this case a resin. It should be appreciated that the reinforcement fibres of the rim portion 102 are laid up as a stacked layers of reinforcement fabric through the rim body 1 18 and flange area 120. The rim portion 102 is laid out with a layered structure. The layer structure, and in particular the internal layer structure shown in Figure 3 is illustrative only. It should be appreciated that any number of different layer structure and configurations could be used for the internal layers of the rim portion 102 without departing from the scope of the present invention. In this respect, the number of layers 126 may vary considerably depending on the design and the size of the rim portion 102 and section thereof. For illustrative purposes, only four layers 126 are shown in the layup of the illustrated portion of the rim portion 102 in Figure 3A and 3B. It should be appreciated that any number of layers 126 of reinforcing fibre, for example 2, 3, 4, 6, 7, 10, 20, 30, 50, 100 or more layers could be used needed to obtain the desired quality and/or properties of the rim portion 102.

[0042] As best shown in Figure 3B, the layers 126 of the layered structure in the first annular bead 122 terminates with the ends 128 of the layers 126 terminating at the edge 129 of the first annular bead 122. [0043] As best shown in Figure 3B, a capping layer 132 comprising a structural reinforcement layer is wrapped around the edge 129 of the first annular bead 122 from the inside surface 124 of the rim body 1 18 to the outside surface 125 of the rim body 1 18. The capping layer 132 covers the ends 128 of all internal layers that terminate at the edge 129 of the first annular bead 122. The annular edges 129 of the rim portion 102, including the exposed ends 128 of the layers 126 of reinforcement fibres are covered by at least one capping layer 132 of reinforcement.

[0044] This capping layer 132 assists in molding the final shape of that annular edge 129. No subsequent machining of the reinforcement is therefore necessary to provide an acceptable finish. The capping layer 132 provides a substantially continuous cover over the respective annular edge 129 and the exposed ends 128 of all internal fibre reinforcement layers 126, so that no fibre ends are exposed.

[0045] As shown in Figure 3A and 3B, the rim body 1 18 includes a second annular bead 130 axially spaced apart from the first annular bead 122. The illustrated capping layer 132 extends over and around the first annular bead 122 and extends over the outside surface 124 to and partially over the second annular bead 132. In some embodiments, the capping layer 132 extends over the second annular bead 132.

[0046] It should be understood that each of the first annular bead 122 and the second annular bead 132 can be formed through shaped stacked layers, or can include and/or be formed through the use of a preform, tow (uni tow), tow-preg or similar.

[0047] A wide variety of fibres may be used in the present invention. In the illustrated embodiment, the reinforcing fibres of the various layers 126 and the capping layer 132 comprise carbon fibres.

[0048] The reinforcement fibres may be provided in any suitable form including in prepregs, semi-pregs, woven or non-woven fabrics, mats, pre-forms, pre- consolidated pre-forms, individual or groups of fibres, tows, tow-pregs, or the like. In the illustrated embodiment, the reinforcement fibres of the layers 126 and the capping layer(s) 132 are provided in the form of fabric sheets, for example a multi-axial fabric sheet or ply. The fabric sheet may comprise a woven or nonwoven fabric.

[0049] Each layer in the rim body 1 18 and capping layer 132 comprises oriented reinforcement fibres, preferably unidirectional fibres, or biaxial reinforcement fibres. In the illustrated embodiment, the orientation of the reinforcement fibres in the capping layer 132 is the same to the orientation of the reinforcement fibres in the rim body 1 18. However, it should be appreciated that this may differ in other embodiments.

[0050] In practice, the rim portion 102 is formed by firstly providing a plurality of layers 126 of reinforcement fibres to form the rim body 1 18 of the rim portion 102 of a composite wheel 100. In this layup, a number of the layers 126 will include an end 129 which extends to at least one of the annular edges 129 of the rim portion 102, for example as shown in Figure 3A and 3B. After this layup is completed, at least one substantially continuous capping layer 132 is wrapped over and around the respective ends 129 of the layers 126 of at least one of the annular edges 129 of the rim body 1 18.

[0051 ] The capping layer 132 can be applied over the annular edges 129 of the rim portion 102 in various ways:

[0052] In some embodiments, as shown in Figure 3A and 3B, each capping layer 132 could be wrapped around the respective annular edge 129 from the inside annular surface 125 to overlap onto the outside annular surface 124 of the rim body 1 18.

[0053] Alternatively, in some embodiments (not illustrated) each capping layer 132 could be wrapped around the respective annular edge 129 from the outside surface 124 to overlap onto the inside surface 125 of the rim body 1 18.

[0054] As discussed above, once the rim portion 102 is laid up, the mold (not shown) containing the component is sealed and a matrix material, such as a metal or resin is provided in contact with each of the layers of the rim portion 102 to inject and/or impregnate those layers with that matrix material.

[0055] In the illustrated wheel, a resin is used. Any suitable resin can be used. In the illustrated embodiment, the resin used is epoxy-based. After resin has full penetrated the reinforcing layers and filled the mold, the resin is allowed to cure. A variety of resin delivery systems can be used such as Resin Infusion and/or Resin Transfer Molding and/or Vacuum Assisted Resin Transfer Molding.

[0056] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is understood that the invention includes all such variations and modifications which fall within the spirit and scope of the present invention.

[0057] Where the terms "comprise", "comprises", "comprised" or "comprising" are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other feature, integer, step, component or group thereof.

Claims

CLAIMS:

1 . A rim component of a composite wheel comprising a rim body formed around a central axis, the rim body axially extending between two annular edges, the rim body comprising:

a plurality of layers of reinforcement fibres, at least one of the layers having an end which extends to at least one of the annular edges; and

at least one substantially continuous capping layer comprised of reinforcement fibres wrapped over and around the respective ends of the layers of at least one of the annular edges of the rim body.

2. A rim component according to claim 1 , wherein the rim body has an outside annular surface and an inside annular surface extending between the annular edges, and wherein the capping layer extends over at least a portion of the inside annular surface and the outside surface of the rim body.

3. A rim component of a composite wheel according to claim 1 or 2, wherein rim body includes at least one first annular bead located at or proximate at least one annular edge, the capping layer extending over the first annular bead.

4. A rim component of a composite wheel claim 3, wherein rim body includes at least one second annular bead axially spaced apart from the first annular bead, the capping layer extending at least to the second annular bead.

5. A rim component of a composite wheel according to claim 4 when dependent on claim 2, wherein the first and second annular beads are located on the outside annular surface of the rim body.

6. A rim component of a composite wheel according to any preceding claim, wherein the rim body includes at least one flange at or proximate the annular edge thereof.

7. A rim component of a composite wheel according to any preceding claim, wherein each layer in the rim component comprises oriented reinforcement fibres, preferably unidirectional fibres or biaxial reinforcement fibres.

8. A rim component of a composite wheel according to any preceding claim, wherein the capping layer comprises oriented reinforcement fibres, preferably unidirectional fibres or biaxial reinforcement fibres.

9. A rim component of a composite wheel according to any preceding claim, wherein the orientation of the reinforcement fibres in the capping layer is at least one of the same, or different to the orientation of the reinforcement fibres in the body portion.

10. A rim component of a composite wheel according to any preceding claim, wherein the reinforcement fibres comprise carbon fibres.

1 1 . A rim component of a composite wheel according to any preceding claim, wherein the reinforcement fibres of the rim body and capping layer are provided as at least one of prepregs, semi-pregs, woven or non-woven fabrics, mats, preforms, pre-consolidated pre-forms, individual or groups of fibres, tows, or tow-pregs.

12. A rim component of a composite wheel according to any preceding claim, wherein the reinforcement fibres of the capping layer are provided as at least one fabric sheet.

13. A rim component of a composite wheel according to any preceding claim, wherein the layers of reinforcement fibres of the rim body comprise at least one fabric sheet.

14. A rim component of a composite wheel claim 12 or 13, wherein the reinforcement fibres comprise at least one multi-axial fabric.

15. A rim component of a composite wheel according to any preceding claim, wherein rim component further comprises a matrix material, preferably a resin, enveloping the reinforcement fibres.

16. A rim component of a composite wheel according to claim 15, wherein the resin are based on unsaturated polyester, polyurethane, polyvinyl ester, epoxy, thermoplastics, similar chemical compounds or combinations thereof.

17. A wheel-rim preform including a rim component according to any one of claims 1 to 16.

18. A composite wheel including a rim component according to any one of claims 1 to 16.

19. A method of forming a rim component of a composite wheel, the rim component comprising a rim body formed around a central axis, the rim body axially extending between two annular edges, the method comprising the steps of:

20. A method of forming a rim component of a composite wheel according to claim 19, using a rim component according to any one of claims 1 to 18.

21 . A method of forming a rim component of a composite wheel according to claim 19 or 20, in which the rim body has an outside annular surface and an inside annular surface extending between the annular edges, and wherein each capping layer comprises a layer of fabric reinforcement which is wrapped around the respective annular edge from the outside annular surface to overlap onto the inside surface of the rim body; or wrapped around the respective annular edge from the inside annular surface to overlap onto the outside annular surface of the rim body.

22. A method of forming a rim component of a composite wheel according to claim 19, 20 or 21 , further including the steps of:

providing a matrix material in contact with each of the layers of the rim component; and

curing the rim component.

23. A method of forming a rim component of a composite wheel according to any one of claims 19 to 22, wherein the fibres for at least one of the layers are provided as one or more prepregs, semi-pregs, woven or non-woven fabrics, mats, pre-forms, pre-consolidated pre-forms, individual or groups of fibres, tows, tow-pregs or a combination thereof.