WO2017221009A1

WO2017221009A1 - An apparatus for manufacturing a composite component

Info

Publication number: WO2017221009A1
Application number: PCT/GB2017/051816
Authority: WO
Inventors: Neil Stafford
Original assignee: Composite Technology And Applications Limited
Priority date: 2016-06-22
Filing date: 2017-06-21
Publication date: 2017-12-28
Also published as: GB201610865D0

Abstract

There is disclosed an apparatus (10) for manufacturing a composite component, comprising: a first tool (12) having a first support surface (22) for engaging a pre-form (100) for the composite component; a second tool (16) having a second support surface (46) for engaging the pre-form (100); a carrier (14) for the second tool (16) having an aperture (26) for withdrawal of the composite component (100) from the apparatus (10), wherein the carrier (14) is configured to receive the second tool (16) in a closed configuration in which the second tool (16) closes the aperture (26), and wherein the second tool (16) is moveable relative the carrier (14) to reveal the aperture (26); and a flexible seal (34) between the first tool (12) and the carrier (14). The first tool (12) and the carrier (14) are configured for relative movement so that, with the second tool (16) in the closed configuration, the first and second support surfaces (22, 46) can be selectively engaged and disengaged around the pre-form. A corresponding method of curing a composite component is also disclosed.

Description

AN APPARATUS FOR MANUFACTURING A COMPOSITE COMPONENT

The invention relates to an apparatus and corresponding method for manufacturing a composite component, and in particular relates to curing a composite component.

Composite components are increasingly used in advanced industries, such as the aerospace industry, owing to the ability to combine desirable material properties, such as high strength and low weight. Composite components are typically formed by laying up plies of fibre reinforcement material on a tool or mandrel to provide a pre-form for the component, and

subsequently curing the pre-form under temperature and/or pressure to produce the component. Recent developments in tool technology have allowed pre-forms to be cured in situ on a tool. This typically involves applying a vacuum bag (or film) over the pre-form on the tool and coupling a low pressure or vacuum source to the space between the tool and vacuum bag so that a pressure force is applied to the pre-form through the vacuum bag.

For simple components, vacuum bags may consist of simple planar sheets and may therefore be relatively inexpensive to use as a consumable. For more complex components, bespoke vacuum bags may be commissioned that correspond to the shape of the pre-form and component in order to avoid undesirable effects such as wrinkling of the vacuum bag during curing. However, such vacuum bags are generally not reusable and may be relatively expensive to use as a consumable.

It is therefore desirable to provide an improved apparatus and method for

manufacturing a composite component. According to a first aspect of the invention there is provided an apparatus for manufacturing a composite component, comprising: a first tool having a first support surface for engaging a pre-form for the composite component; a second tool having a second support surface for engaging the pre-form; a carrier for the second tool having an aperture for withdrawal of the composite component from the apparatus, wherein the carrier is configured to receive the second tool in a closed configuration in which the second tool closes the aperture, and wherein the second tool is moveable relative the carrier to reveal the aperture; and a flexible seal between the first tool and the carrier; wherein the first tool and the carrier are configured for relative movement so that, with the second tool in the closed configuration, the first and second support surfaces can be selectively engaged and disengaged around the pre-form.

The second tool may oppose the first tool and/or the first support surface may oppose the second support surface. The first and second tools may be configured to substantially envelop a pre-form therebetween. The first and second support surfaces may be configured to define the shape of the composite component during curing. The first and second tools may be configured to apply a compression force on a pre-form located therebetween. The first tool and/or the second tool may be provided with heating apparatus for heating the pre-form.

The first tool and the carrier may be configured to move relatively closer together from a disengaged configuration to an engaged configuration. The apparatus may further comprise a stop configured to prevent the first tool and the carrier moving relatively closer together beyond the engaged configuration.

The first tool and the carrier may be configured to move relative one another between the disengaged configuration, in which in use at least one of the first and second support surfaces is disengaged from the pre-form, and the engaged configuration, in which in use both the first and second support surfaces are engaged with the pre-form.

The apparatus may further comprise an aperture seal arranged to provide a gas-tight seal between the carrier and the second tool in the closed configuration. The aperture seal may be configured to prevent gas flow through the aperture when the second tool is in the closed configuration. The aperture seal may comprise an O-ring. The flexible seal may be configured to provide a gas-tight seal between the carrier and the first tool such that, in use with the second tool in the closed configuration, an interior space between the first tool and second tool is sealed from the external environment.

The apparatus may further comprise an extraction port for extracting gas from the apparatus. The extraction port may be located in the carrier. The extraction port may be located in the flexible seal or first tool. The extraction port may be located in any suitable element of the apparatus. There may be a plurality of extraction ports. The apparatus may further comprise a low pressure or vacuum source coupled to the extraction port.

The first tool may be static and the carrier may be configured to move with respect to the first tool. The first tool and the carrier may be configured for relative movement along a longitudinal direction. The apparatus may further comprise an alignment mechanism configured to prevent lateral relative movement between the first tool and the carrier. In other words, the alignment mechanism may be configured such that relative movement between the first tool and the carrier is limited to relative movement along the longitudinal direction only. Accordingly, the tools can be aligned to form a composite component having the desired shape.

The alignment mechanism may comprise at least one guide rail extending from one of the first tool and the carrier and arranged to engage a corresponding guide element coupled to or integral with the other of the first tool and the carrier. The guide element may comprise a hole or groove for receiving the guide rail.

The alignment mechanism may be disposed outside of an interior region of the apparatus at least partly defined by the flexible seal. Accordingly, the alignment mechanism may not be required to incorporate a gas-tight seal.

The flexible seal may comprise a plurality of discrete seal elements. The flexible seal may comprise a bellows.

The alignment mechanism may comprise an alignment member configured to cooperate with corresponding portions of the first tool and the carrier to prevent lateral relative movement between the first tool and the carrier. The alignment mechanism may comprise a plurality of alignment members, for example, a plurality of alignment members circumferentially spaced apart. The or each alignment member may be configured to cooperate with the corresponding portions of the first tool and the carrier to prevent lateral relative movement when the apparatus is in the engaged configuration. The corresponding portions of the first tool and carrier may be recesses, blind holes, or other cooperating formations configured to engage with the alignment member.

The or each alignment member may be resiliently compressible, and may be configured to be compressed as the carrier moves relatively towards the first tool. The or each alignment member may comprise a locating pin (or locating lug) for cooperating with a portion of the first tool or a portion of the carrier, and a resilient member such as a spring. Accordingly, the alignment member may be at least partly compressible. The alignment member may comprise two locating pins (or located lug) coupled by a spring.

The or each alignment member may be configured to bias the first tool and carrier to a disengaged configuration. In other words, the alignment member may be biased to separate the first tool and the carrier.

The apparatus may further comprise a carrier alignment mechanism configured so that the second tool is constrained to be received in the closed configuration in a predetermined orientation. Accordingly, accurate positioning of the second tool relative the first tool in use may be achieved to form a composite component having the desired shape. The carrier alignment mechanism may define only a single

predetermined orientation. Accordingly, the carrier alignment mechanism may ensure that the second tool is oriented correctly relative the first tool to form a composite component having the desired shape.

The carrier alignment mechanism may comprise a series of bolt holes in the second tool and the carrier configured so that the second tool can be secured to the carrier by one or more bolts in a predetermined orientation (only). Alternatively, the carrier alignment mechanism may comprise a carrier guide rail extending from the carrier and a corresponding carrier guide element coupled to or integral with the second tool. The carrier guide element may comprise a hole or groove for receiving the carrier guide rail. There may be a plurality of carrier guide rails and carrier guide elements. There may be at least two, or at least three carrier guide rails and guide elements (e.g. at least two or at least three pairs).

The carrier alignment mechanism may be disposed outside of an interior space of the apparatus at least partly defined by the aperture seal when the second tool is in the closed configuration. Accordingly, the carrier alignment mechanism may not require a gas-tight seal.

The apparatus may further comprise a heat transfer portion formed in or attached to an outer surface of one of the first tool, the second tool and the carrier. There may be a plurality of heat transfer portions. The heat transfer portion may comprise heat transfer features, such as fins, ridges, protrusions and/or recesses for encouraging local heat transfer. The heat transfer portion may have a greater surface area over its extent when compared with the surface area of a flat, continuous or minimum curvature surface having the same extent or boundary.

According to a second aspect of the invention there is provided an apparatus for manufacturing a composite fan blade in accordance with the first aspect of the invention, wherein the first support surface and the second support surface correspond to opposing surfaces of an aerofoil portion of the fan blade.

According to a third aspect of the invention there is provided a method of curing a composite component comprising: providing a pre-form for the composite component on a first support surface of a first tool; causing relative movement between a carrier and the first tool so that a second tool received on the carrier moves from a disengaged configuration to an engaged configuration in which a second support surface of the second tool engages the pre-form; causing the pre-form to cure, including fluidically coupling a sealed space in which the pre-form is disposed to a low pressure or vacuum source, wherein the sealed space is at least partly defined by a flexible seal between the first tool and the carrier; causing the second tool to move relative the carrier from a closed configuration in which an aperture of the carrier is closed to an open configuration to reveal the aperture; and removing the cured composite component from the first tool through the aperture.

Causing the pre-form to cure may include heating the pre-form. The pre-form may be heated by conduction through the first tool and/or the second tool, which may be provided with integrated or attached heating apparatus.

The method may further comprise placing or applying fibre reinforcement material on the first tool through the aperture before the second tool is received on the carrier. The pre-form may be laid up on the first support surface (for example, by hand layup or by an applicator head using ATL (Automatic Tape Laying) or AFP (Automatic Fibre Placement)). Alternatively, the pre-form may be laid up on a separate tool and transferred to the first tool for curing. The method may further comprise moving the second tool relative the carrier from an open configuration to a closed configuration so that the second tool is received on the carrier to sealingly close the aperture, before causing relative movement between the carrier and the first tool from the disengaged configuration to the engaged

configuration.

In the open configuration the aperture may be revealed. In other words, in the open configuration the aperture may be open so that a composite component can be withdrawn from the apparatus, and/or so that fibre reinforcement material can be applied onto the first tool through the aperture. The first tool and the carrier may be moved relatively closer together from the disengaged configuration to the engaged configuration. The first tool and the carrier may be moved relatively closer together until the first tool and/or the carrier engages a stop to prevent further relative movement beyond the engaged configuration. The stop may be mounted to the first tool and the carrier may be moveable towards the first tool until it engages the stop.

The flexible seal may expand and/or contract to accommodate relative movement between the first tool and carrier between the disengaged and engaged configurations, such that in use with the second tool in the closed configuration, an interior space between the first tool and second tool is sealed from the external environment. The flexible seal may comprise a bellows. The method may further comprise extracting gas from an interior space defined between the first tool and the carrier through an extraction port. The carrier may move between the disengaged and engaged configurations whilst the first tool remains substantially stationary. The relative movement between the first tool and the carrier may be along a longitudinal direction.

According to a fourth aspect of the invention there is provided a method of curing a fan blade for a gas turbine engine in accordance with the third aspect of the invention.

According to a fifth aspect of the invention there is provided a method of curing a plurality of composite components comprising conducting a method in accordance with the third or fourth aspects of the invention successive times to cure each composite component, wherein the same flexible seal between the first tool and the carrier is used for each successive composite component.

Methods in accordance with the third, fourth or fifth aspects of the invention may be conducted using an apparatus in accordance with the first or second aspects of the invention.

The invention may comprise any combination of the above-described features, except such combinations as are mutually exclusive. The invention will now be described, by way of example, with reference to the following drawings, in which:

Figure 1 schematically shows an apparatus for curing a composite component; Figure 2 schematically shows the apparatus of Figure 1 with a second tool in a closed configuration;

Figure 3 schematically shows the apparatus of Figures 1 and 2 in an engaged configuration; and Figure 4 schematically shows the apparatus of Figures 1 -3 in a disengaged

configuration with the second tool in an open configuration;

Figure 5 schematically shows a further example apparatus for curing a composite component;

Figure 6 schematically shows a partial view of the apparatus of Figure 5; and

Figure 7 schematically shows a partial view of a further example of a seal between a first tool and carrier of an apparatus for curing a composite component.

As shown in Figure 1 , an apparatus 10 for manufacturing a composite component is provided. The apparatus 10 is for manufacturing a fibre-reinforced plastic aerofoil portion of a fan for a gas turbine blade.

The apparatus 10 comprises a first tool 12, a carrier 14 and a second tool 16 which can be received on the carrier 14. In use, the carrier 14 can be moved relative the first tool such that, when the second tool 16 is received on the carrier 14 in a closed

configuration, the first and second tools 12, 16 engage a pre-form received in the apparatus during curing, thereby defining the shape of the pre-form and cured composite component.

The first tool comprises a base 18 and a die 20 defining a first support surface 22 including side support surfaces 24. The first support surface 22 is configured to correspond to a surface of the composite component. In this particular embodiment, the main portion of the first support surface 22 corresponds to the suction side of a fan blade, and the side support surfaces 24 correspond to leading edge and trailing edge portions to which leading and trailing edge metalwork can later be applied. As shown in Figure 1 , the first support surface 22 is contoured to correspond to the desired shape of the composite component (i.e. the design shape).

The carrier 14 is a generally planar member disposed generally above the first tool 12 and defining a central aperture 26 sized for withdrawing the composite component from the apparatus 10. The carrier 14 is supported above the first tool 12 on an alignment mechanism comprising a plurality of guide rails 28 (two shown) extending from the base 18 of the first tool 12. In this embodiment, the guide rails 28 are substantially cylindrical poles extending parallel to each other in a longitudinal direction which corresponds with the vertical direction as shown in Figure 1 . Corresponding guide elements are formed in the carrier 14 in the form of through-holes for receiving the guide rails 28. The guide elements 30 and guide rails 28 are positioned so that the carrier 14 can move along the longitudinal direction only (i.e. up and down in Figure 1 ), whilst lateral movement (i.e. side-to-side movement) is prevented. In embodiments, the alignment mechanism may be provided with suitable bearings for aiding relative movement, and may be provided with a damping mechanism for ensuring smooth relative movement.

The apparatus further comprises a series of stops 32 mounted on the base 18 of the first tool 12 and configured to limit movement of the carrier 14 towards the first tool 12, as will be described in detail below. The stops 32 (two shown) provide an upper stop surface configured to abut the underside surface of the carrier 14. In other

embodiments, there may be no stops. For example, the second tool may simply be pressed against the pre-form by a predetermined force or until it abuts a portion of the first tool (e.g. a portion of the die).

A flexible seal 34 in the form of a concertinaed bellows is provided around the die 20 between the first tool 12 and the carrier 14. The flexible seal 34 encircles the die 20 and is expandable and contractible along the longitudinal direction to accommodate relative movement between the carrier 14 and the first tool 12. The flexible seal 34 is configured to provide a gas-tight enclosure around the die 20 (and a pre-form received within the apparatus) between the first tool 12 and the carrier 14, and is suitably strong and hard-wearing to be used in multiple curing operations. The shape of the flexible seal 34 around the die 20 (i.e. as viewed from a plan orientation) is adaptable dependent on the component to be manufactured and the corresponding configurations of the first tool 12, carrier 14 and second tool 16. For a composite fan blade, the flexible seal 34 may extend around the die 20 along a generally rectangular profile.

In this embodiment, the seal is composed of platinum cured rubber and is secured to the carrier 14 and first tool 12 using an adhesive (such as the RTV series adhesives available from Momentive Performance Materials Inc., Waterford, N.Y., USA). In other embodiments, the seal may be secured to the carrier 14 using a mechanical fastener, such as bolts, which may be provide for ease of servicing and replacement. The carrier 14 further comprises a plurality of extraction ports 50 which extend through the carrier 14 from an upper surface of the carrier 14 to a lower surface at a position inside of the flexible seal 34, such that a low pressure or vacuum source can be coupled to the extraction ports 50 to extract gas from the interior sealed space of the apparatus 10.

The carrier 14 is also provided with a recess 36 (or ledge) for receiving the second tool 16. The recess 36 includes a planar support surface for supporting the second tool 16, and a shoulder corresponding to the shape of the second tool 16 and configured to prevent lateral movement of the second tool 16 on the carrier 14.

The second tool comprises a support flange 42 shaped to cooperate with the recess 36 of the carrier 34, and a counter-die 44 configured to oppose the die 20 of the first tool 12 and defining a second support surface 46 for engaging the pre-form. In this embodiment, the counter-die is mounted on the support flange 42 so that it can be rigidly suspended underneath it (as shown in Figure 1 ). In other embodiments, the support die may be integrally formed. In this embodiment, the second support surface 46 is contoured to correspond with the pressure side of the aerofoil portion of the composite fan blade. The apparatus further comprises a carrier alignment mechanism including a plurality of carrier guide rails 38 (two shown) extending from the recess 36 of the carrier 14, and a corresponding plurality of carrier guide elements 40 formed in the second tool 16 in the form of through-holes extending through the support flange 42. In other embodiments, the carrier guide elements 40 may be coupled to the second tool rather than integrally formed. The carrier guide rails 38 extend along the longitudinal direction (i.e. generally vertically upwardly in Figure 1 ) and parallel to one another, and the holes 40 are configured to correspond to the carrier guide rails 38. Upper portions of the carrier guide rails 38 are threaded to receive a nut to lock the second tool 16 in place against the carrier 14. In other examples, there may be no carrier guide rails, and the second tool 16 may be simply rest on the carrier 14, and may be held in place in use by a pressure force caused by applying a vacuum or low pressure to the interior of the tool. In such examples there may be cooperating formations in the carrier and second tool to align the second tool on the carrier. In yet further embodiments, the second tool 16 may be fastened to the carrier 14 by one or more mechanical fasteners, such as a series of bolts extending through the tool into threaded holes in the carrier 14 (e.g. as shown in Figure 5).

A carrier seal 48 is disposed between the carrier 14 and the second tool 16. In this particular embodiment, the carrier seal 48 is an O-ring seal disposed on the recess 36 inward of the carrier guide rails 38 and arranged to be depressed between the recess 36 and the support flange 42 of the second tool 16 when the second tool 16 is received on the carrier 14.

A method of forming a composite component using the apparatus 10 will now be described, by way of example, with reference to Figures 1 -4.

Figure 1 shows the apparatus 10 in a preparatory configuration in which the second tool 16 is in an open configuration with respect to the carrier 14, such that the aperture 26 is open, and the carrier 14 and first tool 12 are in a disengaged configuration with respect to each other. In the disengaged configuration, the carrier 14 is elevated from the first tool 12 and the stop 32 such that, if the second tool 16 were to be received on the carrier 14, the second support surface 46 would not engage a pre-form disposed on the first support surface 22. With the apparatus 10 in the preparatory configuration of Figure 1 , a pre-form 100 for the composite component is laid up on the first support surface 22 through the aperture 26. This is possible because the second tool 16 is not received on the carrier 14 and the aperture 26 is open. In this example embodiment, the pre-form 100 is laid up by Automatic Tape Laying (ATL), but in other embodiments other automated techniques may be used, such as Automatic Fibre Placement (AFP), or manual (such as hand layup) or semi-automatic methods.

The pre-form is laid up by applying a plurality of plies of fibre reinforcement material to the first support surface 22 to build up the pre-form 100. Once layup is complete, the second tool 16 is moved to be received on the carrier 14 as shown in Figure 2. The second tool 16 is aligned with the carrier 14 so that the carrier guide elements 40 (the through-holes) are aligned with the carrier guide rails 38, and the second tool 16 is moved longitudinally towards the carrier 14 over the carrier guide rails 38 until it comes to rest on the O-ring 48. The tips of the carrier guide rails 38 project through the support flange 42 of the second tool 16 and nuts (not shown) are secured onto the guide rails 38 to prevent the second tool 16 lifting off the carrier. In this position, the second tool 16 is in the closed configuration with respect to the carrier 14, and the O-ring 48 forms a gas-tight seal between the carrier 14 and the second tool 16. In other embodiments, the second tool 16 may simply be positioned on the carrier 14 without any securing means (such as the nuts), and in use the second tool 16 may be held against the carrier by virtue of the pressure force applied to it, as described below. In this configuration, the carrier 14 and second tool 16 are in a disengaged position with respect to the first tool 12 and the second support surface 46 of the second tool 16 does not engage the pre-form 100.

Since the flexible seal 34 is already disposed between the first tool 12 and the carrier 34, the apparatus 10 now defines a sealed interior space between the flexible seal 34, first tool 12, carrier 34, O-ring 48 and second tool 16 in which the die 20, counter-die 44 and pre-form 100 are disposed.

A low pressure source or vacuum source is coupled to the extraction port 50 (otherwise known as a vacuum breach valve), and the gas within the interior space of the apparatus is extracted as the carrier 14 and second tool 16 are moved downwardly relative the first tool 12 from the disengaged configuration to an engaged configuration in which the carrier 14 rests on the stop 32 and the second support surface 46 engages the upper side of the pre-form 100, as shown in Figure 3. The low pressure or vacuum within the apparatus causes the carrier 14 and second tool 16 to move downwardly and compress the pre-form between the first and second support surfaces 22, 46. In particular, the pressure difference across the second tool 16 and the carrier 14 causes the second tool 16 to be pressed against the carrier 14, and subsequently against the pre-form 100 and first tool 12. With the apparatus in the engaged configuration, the apparatus 10 is heated (either in an autoclave or by direct heating of the first and second tools 12, 16 by integral heaters (not shown)). Under elevated temperature and compression, the pre-form 100 is cured to form a composite component having the desired shape.

The alignment mechanism and carrier alignment mechanism, together with the stop 32 provide for precise positioning of the second tool 16 relative the first tool 12 so that the cured component is formed having the desired shape. After curing, the extraction port 50 is fluidically coupled to atmosphere so that ambient gas enters the interior space of the apparatus and the carrier 14 and second tool 16 are lifted from the engaged configuration to the disengaged configuration, where they may be held by a support (not shown). The second tool 16 is then removed from the carrier 14 to reveal the aperture 26 and return the apparatus to an open configuration, as shown in Figure 4.

In this open configuration of the apparatus, the cured component 100 can be removed from the first tool 12 through the aperture 26. The above-described method can be repeated for curing successive preforms/components without replacing the seals 34, 48. Accordingly, the apparatus and method prevent waste of resources and expense.

Figures 5 and 6 show a second example of an apparatus 1 10 for manufacturing a composite component, in particular, an aerofoil portion of a composite fan blade. The second example apparatus 1 10 differs from the first example apparatus 10 in the specific form and arrangement of the attachments between the first tool 1 12 and the carrier 1 14, and between the carrier and the second tool 1 16. In particular, the alignment mechanism 128 comprises a plurality of alignment members embedded in co-operating recesses 130, 132 circumferentially spaced apart in the first tool 1 12 and carrier 1 14 respectively. As shown in detail in Figure 6, in this embodiment the alignment member 128 comprises a compressible spring portion 131 configured to be received in a cylindrical-shape recess 130 in the first tool 1 12, and a head portion 133 configured to be received in the frustoconical shape recess 132 in the carrier 1 14. The spring portion 131 is configured to bias the carrier 1 14 away from the first tool 1 12, so that the apparatus 1 10 is biased to a disengaged configuration in use. The plurality of alignment mechanisms are configured to prevent lateral movement of the carrier 1 14 relative to the first tool 1 12.

The second example apparatus 1 10 also differs in that the seal 134 is disposed radially outside of the alignment mechanism 128, and in this example is in the form of a spring bellows clip secured around the radially outer edges of the first tool 1 12 and the carrier 1 14 respectively. Accordingly, since the alignment mechanism 128 is embedded in cooperating recesses within the first tool 1 12 and the carrier 1 14, and radially inside the seal 134, it is entirely within the volume sealed by the seal 134. Providing the alignment mechanism 128 radially within the seal 134 and embedded between the first tool 1 12 and carrier 1 14 may reduce the maintenance burden for the alignment mechanism 128, for example, because it may be protected from dirt ingress from the external environment. Further, the alignment mechanism 128 does not extend through the upper or outer surface of the carrier 1 14, and therefore does not present a leakage flow path.

Further, the second example apparatus 1 10 differs in that the carrier alignment mechanism comprises a series of bolts 141 which extend through a clearance hole in the second tool 1 16 and into threaded holes in the carrier 1 14 to fixedly secure the second tool 1 16 to the carrier 1 14. The bolts 141 are disposed radially outside of the carrier seal 148 between the second tool 1 16 and the carrier 1 14. As shown in Figure 5, in this embodiment heat transfer portions 152 are formed in the second tool 1 16 on its outer surface (the upper surface in Figure 5), comprising heat transfer features such as heat transfer fins or a plurality of protrusions for promoting heat transfer. In this example, the heat transfer portions 152 comprise a series of heat transfer fins machined into the upper surface of the second tool 1 16, but in other embodiments the heat transfer portions 152 may take any form arranged to increase the local surface area for heat transfer, when compared to the surrounding profile of the respective tool. Heat transfer portions 152 may, in addition or alternatively, be provided on the carrier 1 14 and/or first tool 1 12. In other embodiments, the heat transfer portions may be discrete elements attachable to one or more of the first tool 1 12, carrier 1 14 and second tool 1 16. In use, the spring portion 131 of the alignment mechanism 128 biases the carrier 1 14 to a disengaged configuration during a layup procedure conducted through the aperture defined by the carrier. A preform is laid up on the first tool 1 12 ready for curing. The second tool 1 16 is placed onto the carrier 1 14 and secured to the carrier 1 14 with bolts 141 . A vacuum or low pressure source is applied to the interior space of the tool through an extraction port 150 in the second tool 1 16, as described above with respect to the first example apparatus 10, such that a pressure force on the carrier 1 14 and second tool 1 16 causes the carrier 1 14 to move relative the first tool 1 12, thereby compressing the alignment mechanism until the carrier 1 14 abuts the first tool 1 12 (which thereby acts as a stop). Accordingly, the apparatus 1 10 reaches the engaged configuration in which the die 120 and counter-die 144 engage around the preform. A curing operation is then conducted under high pressure and temperature. The curing operation may be conducted in an autoclave or using direct heating of the apparatus. When heating in an autoclave, the heat transfer portions 152 locally increase heat transfer to the respective tool 1 12, 1 14, 1 16, owing to the locally high surface area.

Subsequently, the interior of the apparatus is once again coupled to ambient conditions to release the pressure force and allow the carrier 1 14 to be moved by the biasing force of the alignment members 128 relatively away from the first tool 1 12 to a disengaged configuration. The apparatus is therefore opened by the spring force of the alignment members 128. The bolts 141 are uncoupled and the second tool 1 16 is removed from the carrier 1 14 to expose the cured component, which is subsequently removed. The seal 134 can be used for multiple curing operations, as can the carrier seal 148.

Figure 7 shows a further example apparatus which differs from the second example apparatus shown above in the form of connection of the seal 134 to the first tool 1 12 and the carrier 1 14. As shown in Figure 7, the flexible seal 134 is in the form of a flexible bellows extending from a first end coupled to the first tool 1 12 to a second end coupled to the carrier 1 14. Each end of the seal 134 is provided with a locating projection 135, which in this example is a bead, configured to be received in a cooperating groove in the first tool 1 12 or carrier 1 14 respectively. The respective ends are secured in place by securing strips 154 corresponding to the outer profile of the first tool 1 12 and the carrier 1 14 respectively. In this example, the securing strips 154 are secured in place by bolts 156 extending through the strips 154 and into the first tool 1 12 or carrier 1 14 respectively, such that the bolts 156 do not extend directly through the material of the seal 134. This arrangement may maintain integrity of the seal 134, and may provide for simple removal and replacement of the seals 134, and servicing of the internal components of the apparatus, by removing the bolts 156, securing strips 154 and seal 134.

Placing the flexible seal away from the pre-form enables the support surfaces of the first and second tools to form the shape of the composite component during curing without the need to place a consumable flexible seal membrane (such as a vacuum bag) against the pre-form. This is because the support surfaces of the first and second tools are within the sealed environment. Whilst such an arrangement may normally prevent the insertion and removal of a pre-form and composite component from the apparatus, the provision of an aperture in the carrier and a second seal between the second tool and the carrier, which closes the aperture, enables insertion and removal of the pre-form/composite component. The carrier seal can be easily maintained and replaced. Further, the elimination of the consumable flexible seal membrane helps to improve heat transfer through the apparatus (e.g. when placed in an autoclave), as there is no need to place a seal membrane over the apparatus. Accordingly, heat transfer is enabled directly between the surrounding environment (i.e. within the autoclave) and the apparatus (e.g. through the first tool, the second tool, and/or the carrier), and such heat transfer may be improved where heat transfer portions are provided, for example, including heat transfer fins. Since the flexible seal is formed between the first tool and the carrier, rather than extending over a pre-form, the carrier and second tool can adopt a fixed position relative the first tool in use, as defined by the alignment mechanism, such that a component of the desired shape can be accurately formed.

Claims

CLAIMS:

1 . An apparatus for manufacturing a composite component, comprising:

a first tool having a first support surface for engaging a pre-form for the composite component;

a second tool having a second support surface for engaging the pre-form;

a carrier for the second tool having an aperture for withdrawal of the composite component from the apparatus, wherein the carrier is configured to receive the second tool in a closed configuration in which the second tool closes the aperture, and wherein the second tool is moveable relative the carrier to reveal the aperture; and

a flexible seal between the first tool and the carrier;

wherein the first tool and the carrier are configured for relative movement so that, with the second tool in the closed configuration, the first and second support surfaces can be selectively engaged and disengaged around the pre-form; and

wherein the flexible seal is configured to expand and/or contracts to

accommodate relative movement between the first tool and the carrier between the disengaged and engaged configurations, such that in use with the second tool in the closed configuration, an interior space between the first tool and second tool is sealed from the external environment.

2. An apparatus according to claim 1 , wherein the first tool and the carrier are configured to move relatively closer together from a disengaged configuration to an engaged configuration.

3. An apparatus according to claim 2, further comprising a stop configured to prevent the first tool and the carrier moving relatively closer together beyond the engaged configuration.

4. An apparatus according to any preceding claim, further comprising an aperture seal arranged to provide a gas-tight seal between the carrier and the second tool in the closed configuration.

5. An apparatus according to claim 4, wherein the aperture seal comprises an O- ring.

6. An apparatus according to any preceding claim, wherein the flexible seal is configured to provide a gas-tight seal between the carrier and the first tool such that, in use with the second tool in the closed configuration, an interior space between the first tool and second tool is sealed from the external environment.

7. An apparatus according to any preceding claim, further comprising an extraction port for extracting gas from the apparatus.

8. An apparatus according to claim 7, further comprising a low pressure or vacuum source coupled to the extraction port.

9. An apparatus according to any preceding claim, wherein the first tool is static and the carrier is configured to move with respect to the first tool.

10. An apparatus according to any preceding claim, wherein the first tool and the carrier are configured for relative movement along a longitudinal direction.

1 1 . An apparatus according to claim 10, further comprising an alignment mechanism configured to prevent lateral relative movement between the first tool and the carrier.

12. An apparatus according to claim 1 1 , wherein the alignment mechanism comprises an alignment member configured to cooperate with corresponding portions of the first tool and the carrier to prevent lateral relative movement between the first tool and the carrier.

13. An apparatus according to claim 12, wherein the alignment member is resiliently compressible, and is configured to be compressed as the carrier moves relatively towards the first tool.

14. An apparatus according to claim 13 when appendant to claim 2, wherein the alignment member is configured to bias the first tool and carrier to a disengaged configuration.

15. An apparatus according to any preceding claim, further comprising a carrier alignment mechanism configured so that the second tool is constrained to be received in the closed configuration in a predetermined orientation.

16. An apparatus according to claim 14 or 15 when appendant to claim 4, wherein the carrier alignment mechanism is disposed outside of an interior space of the apparatus at least partly defined by the aperture seal when the second tool is in the closed configuration.

17. An apparatus according to any preceding claim, further comprising a heat transfer portion formed in or attached to an outer surface of one of the first tool, the second tool and the carrier.

18. An apparatus for manufacturing a composite fan blade in accordance with any preceding claim, wherein the first support surface and the second support surface correspond to opposing surfaces of an aerofoil portion of the fan blade.

19. A method of curing a composite component comprising :

providing a pre-form for the composite component on a first support surface of a first tool;

causing relative movement between a carrier and the first tool so that a second tool received on the carrier moves from a disengaged configuration to an engaged configuration in which a second support surface of the second tool engages the preform;

causing the pre-form to cure, including fluidically coupling a sealed space in which the pre-form is disposed to a low pressure or vacuum source, wherein the sealed space is at least partly defined by a flexible seal between the first tool and the carrier; causing the second tool to move relative the carrier from a closed configuration in which an aperture of the carrier is closed to an open configuration to reveal the aperture; and

removing the cured composite component from the first tool through the aperture; wherein the flexible seal expands and/or contracts to accommodate relative movement between the first tool and carrier between the disengaged and engaged configurations, such that in use with the second tool in the closed configuration, an interior space between the first tool and second tool is sealed from the external environment..

20. A method according to claim 19, further comprising placing or applying fibre reinforcement material on the first tool through the aperture before the second tool is received on the carrier.

21 . A method according to claim 19 or 20, further comprising moving the second tool relative the carrier from an open configuration to a closed configuration so that the second tool is received on the carrier to sealingly close the aperture, before causing relative movement between the carrier and the first tool from the disengaged configuration to the engaged configuration.

22. A method according to any of claims 19 to 21 , further comprising extracting gas from an interior space defined between the first tool and the carrier through an extraction port.

23. A method according to any of claims 19 to 22, wherein the carrier moves between the disengaged and engaged configurations whilst the first tool remains substantially stationary.

24. A method according to any of claims 19 to 23, wherein the relative movement between the first tool and the carrier is along a longitudinal direction.

25. A method of curing a fan blade for a gas turbine engine in accordance with any of claims 19 to 24.

26. A method of curing a plurality of composite components comprising conducting a method in accordance with any of claims 19 to 25 successive times to cure each composite component, wherein the same flexible seal between the first tool and the carrier is used for each successive composite component.