GB2598705A

GB2598705A - Moulding system and method

Info

Publication number: GB2598705A
Application number: GB2010774.4A
Authority: GB
Inventors: Hall Richard
Original assignee: Great British Sports Cars Ltd
Current assignee: Great British Sports Cars Ltd
Priority date: 2020-07-13
Filing date: 2020-07-13
Publication date: 2022-03-16
Also published as: GB202010774D0

Abstract

A moulding system 1 comprises a moulding surface 22 formed on or in a slab 21, a chamber 31 mounted opposite the moulding surface, which is at least partially described by a deformable wall 35 and fluid supply means 4 connected to the chamber for supplying a pressurised heat transfer fluid to it. The system is configured to control the volume and pressure of pressurised heat transfer fluid supplied to the chamber in order to cause the deformable wall to heat or cool and force a mouldable material 7 against the moulding surface. The deformable wall may be sealingly secured about the periphery of a hood 30 that describes a concave depression such that the chamber is described therebetween.

Description

MOULDING SYSTEM AND METHOD

This invention relates generally to moulding systems and methods. More specifically, although not exclusively, this invention relates to moulding systems and methods for moulding composite mouldings, such as fibre reinforced plastics mouldings.

Composite mouldings are well-known and generally comprise components or products produced by impregnating a fibrous material with a bonding medium to form laminates or layers. The bonding medium is normally a thermoplastic or thermocuring resin that is io hardened or cured within and around a matrix of the fibrous material. The bonding medium may be added during the moulding process or may be impregnated within a sheet of fibrous material, commonly referred to as "prepreg".

These composite mouldings are well known and widely used in industry for producing components having a high strength to weight ratio. In use, pressure and heat are normally applied to force air out, to remove excess resin and to cure the composite. This may be carried out in an autoclave or using a press with heated dies to compress the elements of the composite and to accelerate curing. Both autoclave and heated moulding presses require equipment that is expensive and complex to purchase, operate and maintain particularly when producing large components.

EP0805746 describes a system for manufacturing a composite component involving compressing and heating a composite lay-up between a rigid moulding wall and a deformable backing wall. Each wall is movable and closes a respective pressure chamber through which fluid is circulated at substantially the same elevated temperature and pressure to compress and heat the composite lay-up. The backing wall is formed of a readily deformable membrane which deforms to follow the general shape of the composite lay-up compressed against the rigid moulding wall. Both pressure chambers are fed by the same reservoir to ensure that the same temperature and pressure is applied to each. Whilst effective and less expensive than some preceding processes sought to be replaced by the process disclosed in this document, the bespoke nature of the moulds required can be expensive and the inherent complexities of this process can also present problems.

EP2368700 describes a moulding system similar to that of EP0805746, but in which the deformable backing wall is above the rigid moulding wall and a liquid is received thereon to create a fluid pressure due to the density of the liquid. The system described in EP2368700 also includes a resin supply for wetting a fibre reinforcing material received between the backing and moulding walls.

The present invention seeks to provide an alternative system and method, preferably one that at least mitigates some of the issues with known prior art processes and/or that is more cost effective.

Accordingly, a first aspect of the invention provides a moulding system comprising a moulding surface, e.g. a non-moving moulding surface, a chamber mounted opposite the io moulding surface which is at least partially described by a deformable wall and fluid supply means connected to the chamber for supplying a pressurised heat transfer fluid thereto, wherein the system is configured to control, in use, the volume and/or pressure and/or temperature of pressurised heat transfer fluid supplied to the chamber to cause the deformable wall to heat, cool, solidify and/or force a mouldable material, e.g. a resin-impregnated fibre matrix, against the moulding surface.

The applicant has determined that good quality composite articles can be produced by introducing heat from only one side of a mouldable material, such as a resin impregnated fibre matrix. For example, the present invention enables the resin curing process to begin on the side of the mouldable material which faces the deformable, heated wall and to propagate through the matrix to cure the resin throughout.

As such, it is possible to form a non-movable moulding surface by machining (or any other suitable process) a low-cost substrate, such as a concrete or other aggregate material, rather than providing a movable moulding wall as in EP0805746. It should be appreciated, however, that the non-movable moulding surface or substrate on which it is formed could be heated, but such heating is not necessary.

The system may comprise a substrate, slab or block. The moulding surface may be formed 30 or described thereon or therein. The system may comprise a cover or hood. The cover or hood may describe at least part of the chamber.

Another aspect of the invention provides a moulding system comprising a substrate, slab or block with a moulding surface, a cover or hood mounted opposite the moulding surface 35 and describing a chamber, a deformable wall closing the chamber and fluid supply means connected to the chamber for supplying a pressurised heat transfer fluid thereto, wherein the system is configured to control, in use, the volume and/or pressure and/or temperature of pressurised heat transfer fluid supplied to the chamber to cause the deformable wall to heat, cool, solidify and/or force a mouldable material, e.g. a resin-impregnated fibre matrix, against the moulding surface.

The cover or hood may comprise a depression, e.g. a concave depression, which may have an open side that may be described by a periphery of the cover or hood. The deformable wall may be secured, e.g. sealingly secured, about the periphery of the cover or hood, for io example internal of the periphery or on the periphery. The chamber may be described between the cover or hood and the deformable wall. The cover or hood may comprise a peripheral wall or flange.

The deformable wall may be secured, e.g. sealingly secured, about and/or along the peripheral wall or flange. The periphery or wall or flange may be configured to abut the substrate, slab or block. The deformable wall may be configured to be urged or forced against the substrate, slab or block, for example by the cover, hood, periphery of the hood, wall or flange. The deformable wall may be configured to be sandwiched between the substrate, slab or block and the cover, hood, periphery of the hood, wall or flange.

The system or fluid supply means may comprise a pump, e.g. one or more pumps. The pump(s) may fluidly connect the chamber to a reservoir. The system or fluid supply means may comprise a valve means, for example a valve, which may comprise a control valve. The system or fluid supply means may comprise a heating element, e.g. for heating the fluid supplied to the chamber. The cover, hood or reservoir may comprise the heating element. The heating element may be located in or on the cover, hood or reservoir.

The pump(s) may comprise one or more feed pumps. The pump(s) may comprise one or more return pumps. The pump(s) may comprise a first or feed pump, which may fluidly 30 connect an inlet of the chamber to the reservoir. The pump(s) may comprise a second or retum pump, which may fluidly conned an outlet of the chamber to the reservoir.

The system may be configured to operate, in use, the or each pump, for example individually. The pump(s) and/or valve means may be operable or operated to control the 35 volume and/or pressure and/or temperature of pressurised heat transfer fluid supplied to and/or removed from the chamber. The system may be operable to generate a negative pressure within the chamber, for example such that at least part of the deformable wall retracts into the chamber, cover or hood.

The system may comprise a frame or platen. The substrate, slab or block may be mounted to or received in or on the frame or platen. The substrate, slab or block may be removable from the frame or platen. The chamber, cover or hood may be movable, in use, relative to the frame or platen.

io The chamber, cover or hood may comprise an open position, e.g. in which it is spaced from the moulding surface. The chamber, cover or hood may comprise a closed position, e.g. in which the periphery of the hood surrounds the moulding surface. The chamber, cover or hood may be movable from the open position to the closed position and/or from the closed position to the open position.

The deformable wall, e.g. part thereof, may be clamped between the cover, hood, periphery of the hood, peripheral wall or flange of the hood and the substrate, slab, block, frame or platen, e.g. when the chamber, cover or hood is in the closed position.

In some embodiments, the chamber is described by a resilient member, which may be hollow and/or tubular. The substrate, slab or block may comprise a hollow portion or a cavity, such as a cylindrical hollow portion or cavity. The hollow portion or cavity may comprise or describe the moulding surface. The tubular member may be receiveable, in use, in the hollow portion or cavity. The tubular member may be configured or operable to expand, in use, whilst it is received within the hollow portion or cavity, e.g. thereby to heat, cool, solidify and/or force a mouldable material against the moulding surface.

The substrate, slab or block may comprise a concrete material. Alternatively, the substrate, slab or block may comprise stone or an aggregate material other than concrete. The substrate, slab or block may be unheated, for example apart from any consequential heating by the deformable wall. The substrate, slab or block may be free of a heating means or heating element or heater. The deformable wall may comprise an elastomeric material.

The system may comprise a controller, which may be operatively connected to the fluid 35 supply means. The controller may be operatively connected to one or more sensors, e.g. for sensing a flowrate and/or pressure and/or a temperature of heat transfer fluid within the chamber and/or reservoir and/or circuit between the chamber and/or reservoir and/or pump(s). The controller may be configured to control the fluid supply means in response to a flowrate and/or pressure and/or temperature sensed by the sensor(s). The controller may be configured to control the temperature of the Another aspect of the invention provides a method of moulding a composite article, e.g. using the aforementioned system. The method may comprise placing a mouldable material, such as a resin-impregnated fibre matrix, between a moulding surface, e.g. a non-moving io moulding surface, and a deformable wall of a chamber. The chamber or deformable wall may be mounted opposite the moulding surface. The method may comprise supplying pressurised heat transfer fluid to the chamber, for example in order to cause the deformable wall to heat, cool, solidify or cure the mouldable material and/or to force the mouldable material against the moulding surface. The method may comprise allowing at least part of the mouldable material to solidify or cure.

The method may comprise retracting at least part of the deformable wall, e.g. into the cover, after at least part of and/or before all of the mouldable material is solidified or cured. The method may comprise retracting at least part of the deformable wall, e.g. into the cover, after at least part of the resin of the fibre matrix is cured and/or before the resin of the fibre matrix is completely cured. Alternatively, the method may comprise retracting at least part of the deformable wall, e.g. into the cover, after the mouldable material, e.g. the resin of the fibre matrix, is completely solidified or cured.

The method may comprise supplying pressurised heat transfer fluid from a reservoir to the chamber, e.g. at a first rate. The method may comprise discharging or evacuating heat transfer fluid from the chamber to the reservoir, e.g. at a second rate. The second rate may be lower than the first rate, e.g. to cause the deformable wall to compress and heat the mouldable material against the moulding surface. The second rate may be higher than the first rate, e.g. to retract the deforrnable wall or part thereof. The first and/or second rate may be varied, for example to vary the pressure within the chamber and/or to vary the force applied to the mouldable material. The method may comprise varying the pressure within the chamber, for example varying the pressure profile over time and/or during the moulding cycle.

The method may comprise forming a moulding surface in or on a substrate, e.g. a slab or block of material such as concrete, to provide the moulding surface. The moulding surface may be formed in or on the substrate, slab or block by machining.

Another aspect of the invention provides a mould, e.g. for use in the system or method described above. The mould may comprise a moulding surface described or defined in, on or by a substrate. The substrate may comprise a slab or block of material, e.g. a slab or block of stone, concrete or other aggregate material.

io The substrate may comprise a cavity within which at least a portion of the moulding surface is described. Additionally or alternatively, the substrate may comprise a projection on which at least a portion of the moulding surface is described. The moulding surface is preferably provided by the material of the substrate, slab or block. In some embodiments, however, the moulding surface may be provided by a different material to the substrate, slab or block.

The substrate may comprise a coating, plating, insert or jacket, which may provide at least part of the moulding surface. For example, where the substrate comprises a depression or cavity within which at least a portion of the moulding surface is described, an inner surface of the depression or cavity may comprise or receive a coating, plating or insert. Where the substrate comprises a projection on which at least a portion of the moulding surface is described, a surface of the projection may comprise or receive a coating, plating or jacket thereon.

For the avoidance of doubt, any of the features described herein apply equally to any aspect of the invention. For example, the system may comprise any one or more features described in relation to the mould or method relevant thereto and/or the method may comprise any one or more features or steps relevant to one or more features of the system or mould.

Another aspect of the invention provides a computer program element comprising and/or describing and/or defining a three-dimensional design for use with a simulation means or a three-dimensional additive or subtractive manufacturing means or device, e.g. a three-dimensional printer or CNC machine, the three-dimensional design comprising an embodiment of the mould, substrate, slab or block described above.

A further aspect of the invention provides a computer program element comprising computer readable program code means for causing a processor to execute a procedure to implement one or more steps of the aforementioned method.

A yet further aspect of the invention provides the computer program element embodied on a computer readable medium.

A yet further aspect of the invention provides a computer readable medium having a program stored thereon, where the program is arranged to make a computer execute a 10 procedure to implement one or more steps of the aforementioned method.

A yet further aspect of the invention provides a control means or control system or controller comprising the aforementioned computer program element or computer readable medium.

For purposes of this disclosure, and notwithstanding the above, it is to be understood that any controller(s), control units and/or control modules described herein may each comprise a control unit or computational device having one or more electronic processors. The controller may comprise a single control unit or electronic controller or altematively different functions of the control of the system or apparatus may be embodied in, or hosted in, different control units or controllers or control modules. As used herein, the terms "control unit" and "controller' will be understood to include both a single control unit or controller and a plurality of control units or controllers collectively operating to provide the required control functionality.

A set of instructions could be provided which, when executed, cause said controller(s) or control unit(s) or control module(s) to implement the control techniques described herein (including the method(s) described herein). The set of instructions may be embedded in one or more electronic processors, or alternatively, may be provided as software to be executed by one or more electronic processor(s). For example, a first controller may be implemented in software run on one or more electronic processors, and one or more other controllers may also be implemented in software run on or more electronic processors, optionally the same one or more processors as the first controller. It will be appreciated, however, that other arrangements are also useful, and therefore, the present invention is not intended to be limited to any particular arrangement. In any event, the set of instructions described herein may be embedded in a computer-readable storage medium (e.g., a non-transitory storage medium) that may comprise any mechanism for storing information in a form readable by a machine or electronic processors/computational device, including, without limitation: a magnetic storage medium (e.g., floppy diskette); optical storage medium (e.g.. CD-ROM); magneto optical storage medium; read only memory (ROM); random access memory (RAM); erasable programmable memory (e.g., EPROM ad EEPROM); flash memory; or electrical or other types of medium for storing such information/instructions.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and altematives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. For the avoidance of doubt, the terms "may", "and/or', "e.g.", "for example' and any similar term as used herein should be interpreted as non-limiting such that any feature so-described need not be present. Indeed, any combination of optional features is expressly envisaged without departing from the scope of the invention, whether or not these are expressly claimed. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which: Figure 1 is a schematic of a moulding system according to an embodiment of the invention; and Figure 2 is a flow diagram of a moulding process according to an embodiment of the invention.

Referring now to Figure 1, there is shown a moulding system 1 including a fixed mould section 2, a moving mould section 3, a heating fluid supply sub-system 4, a hydraulic power circuit 5 and a controller 6. In this embodiment, the fixed mould section 2 and moving mould section 3 together define a moulding press that is actuated by the hydraulic power circuit 5 under the control of the controller 6 to mould a resin-impregnated fibre matrix 7 received between the mould sections 2, 3.

The fixed mould section 2 includes a base 20, depicted as a platform in this embodiment, on which is mounted a substrate 21 having a moulding surface 22 defined on an upper surface thereof. In this embodiment, the substrate 21 is a slab of concrete from which the moulding surface 22 is machined. The machined moulding surface 22 of the slab of concrete may carry a coating, such as a release coating or a wear resistant material. In this embodiment, the moulding surface 22 includes both a projecting portion 22a and a io depression or cavity 22b. The substrate 21 is also unheated, apart from any consequential heating that occurs during the moulding process 100.

The moving mould section 3 includes a cover or hood 30 describing a concave chamber 31 with an open side described by a periphery 32 of the hood 30. The chamber 31 has an inlet 33 for receiving pressurised heating fluid from the heating fluid supply sub-system 4 and an outlet 34 for discharging heating fluid to the heating fluid supply sub-system 4.

The open side of the hood 30 is closed by a deformable wall 35, which is sealingly secured about the periphery 32 of the hood 30. More specifically, the deformable wall 35 is sandwiched between a flange 36 extending about the periphery 32 and rails 37 secured to the flange 36 by bolts (not shown) that extend through the deformable wall 35 and into threaded holes (not shown) in the flange 36.

The deformable wall 35 forms a lower wall of the chamber 31 and faces the moulding surface 22 of the fixed mould section 2. The heating fluid supply sub-system 4 is configured to supply pressurised heating fluid to the chamber 31 in order to cause the deformable wall 35 to heat and force the resin-impregnated fibre matrix 7 against the moulding surface 22. In this embodiment, the deformable wall 35 is formed of an elastomeric material.

The hood 30 is mounted to a frame 23 by a pair of hydraulic cylinders 50 of the hydraulic power circuit 5. The frame 23 is fixed to the base 20 of the fixed mould section 2, for example by columns (not shown), and the hydraulic cylinders 50 are mounted to a lower part of the frame 23. Each hydraulic cylinder 50 includes a piston rod 51 having a free end connected to the hood 30. The piston rod 51 reciprocates within the cylinder 50 in the usual way to move the hood 30.

In this embodiment, the hood 30 is movable from an open position to a closed position. In the open position, the hood 30 is spaced from the moulding surface 22. In the closed position, the rails 37 abut the substrate 21 and the periphery 32 of the hood 30 surrounds the moulding surface 22. It will be appreciated that a hydraulic pressure applied to the cylinder 50 with the hood 30 in the closed position will cause the deformable wall 35 to be compressed between the flange 36 and the substrate 21 to further improve the seal between the deformable wall 35 and the hood 30.

io The heating fluid supply sub-system 4 includes a reservoir 40 with a heating element 41, a feed pipe 42 fluidly connected to the inlet 33 of the chamber 31 of the hood 30 and a return pipe 43 fluidly connected to the outlet 34 of the chamber 31. The heating fluid supply subsystem 4 also includes a feed pump 44 (although multiple feed pumps 44 are also envisaged) connected to the feed pipe 42 between the reservoir 40 and the chamber 31 and a return pump 45 (although multiple return pumps 45 are also envisaged) connected to the return pipe 43 between the chamber 31 and the reservoir 31.

In use, the flow of heating fluid into and out of the chamber 31 of the hood 30 is effected by the pumps 44, 45. More specifically, a net flow of heating fluid into or out of the chamber 31 is effected by operating the pumps 44, 45 at different flow rates. For example, a net flow of heating fluid into the chamber 31 can be effected by causing the feed pump 44 to operate at a higher rate of flow than the return pump 45. Similarly, a net flow of heating fluid out of the chamber 31 can be effected by causing the return pump 45 to operate at a higher rate of flow than the feed pump 44.

Both pumps 44, 45 may operate at a positive flow during the moulding cycle to ensure that the heating fluid is recirculated to maintain the requisite temperature within the hood 30. Indeed, when the heating fluid within the chamber 31 of the hood 30 reaches desired volume and pressure, recirculation can be effected by running both pumps 44, 45 at the same flow rate.

The hydraulic power circuit 5 includes a reservoir 52 of hydraulic fluid, a pump 53 and a valve 54 coupled to the reservoir 52 for supplying pressurised hydraulic fluid to the cylinders 50 in order to move the hood 30 relative to the substrate 21. The pump 53 and valve 54 are both operatively connected to the controller 6, which controls their operation.

The moulding system 1 also includes a plurality of sensors 60, 61, 62, 63, 64, 65, 66 operatively connected to the controller 6 to monitor the operation thereof and a user interface 67 to enable a user (not shown) to input process parameters for controlling the moulding process 100. A hood temperature sensor 60 and a hood pressure sensor 61 are provided for measuring, respectively, the temperature and pressure of heating fluid in the chamber 31 of the hood. A reservoir temperature sensor 62 is provided for measuring the temperature of heating fluid within the reservoir 40 of the heating fluid supply sub-system 4.

A power circuit pressure sensor 63 is provided for measuring the pressure of hydraulic fluid supplied by the pump 53 to the cylinders 50 of the power circuit 5. The system 1 includes a substrate proximity sensor 64 for detecting the presence of a substrate 21 and a mould closed proximity sensor 65 for detecting whether the hood 30 is in its closed position. The system 1 also includes a mould open proximity sensor 66 for detecting whether the hood 30 is in the open position, thereby providing failsafe feedback of the position of the hood 30. Whilst illustrated schematically, the proximity sensors 64, 65,66 are preferably mounted relative to the frame 23.

Referring now to Figure 2, a process 100 of moulding a composite product using the moulding system 1 is illustrated. The process 100 involves setting 101 the desired temperature of the hood 30 via the user interface 67, which initiates 102 the heating fluid supply sub-system 4. This causes the heating element 41 to heat the heating fluid within the reservoir 40 and causes the pumps 44, 45 to operate at substantially the same flow rate to circulate heating fluid through the chamber 31 in the hood 30 until the temperature setpoint is reached. The controller 6 monitors 103 the temperature within the hood 30 via the hood temperature sensor 60 and when the measured temperature reaches the setpoint, the user interface 67 alerts the user (not shown) that the system 1 is ready for operation.

The user (not shown) then places 104 the resin-impregnated fibre matrix 7 on the moulding surface 22 and sets 105, via the user interface 67, the process time and pressure. The mould closes 106 and the hood 30 is pressurised 107. More specifically, the feed pump 44 is operated at a higher flow rate to the return pump 45 in order to fill the chamber 31 of the hood 30 with heating fluid, thereby displacing the deformable wall 35 toward the moulding surface 22.

Continued filling of the chamber 31 causes the deformable wall 35 to force the resin-impregnated fibre matrix 7 against the moulding surface 22. Heat is transmitted from the heating fluid within the hood 30 through the deformable wall 35 and into the resin-impregnated fibre matrix 7. When sufficient heat is transmitted, the resin in the fibre matrix 7 begins to cure.

It has been determined that, in some cases, once a predetermined amount of the resin in the fibre matrix 7 has begun to cure, curing will continue even if heat is no longer applied.

io As such, once at least part of the resin in the fibre matrix 7 has begun to cure, the hood 30 is depressurised 108 by operating the return pump 45 at a higher flow rate than the supply pump 44.

In this embodiment, the shape of the hood 30 is such that continued operation of the pumps 44,45 in this manner will retract the deformable wall 35 into the hood 30, as shown in Figure 1. This enables the hood 30 to be moved relative to the substrate 21 without being damaged, which might otherwise occur due to the projection 22a of the moulding surface 22. The mould is then opened 109 and the cured or at least partially cured composite can be removed 110. Where the composite is only partially cured, it may then be placed 111 on a jig (not shown) for curing to be completed.

It will be appreciated by those skilled in the art that several variations to the aforementioned embodiments are envisaged without departing from the scope of the invention. For example, the substrate 1 need not be provided by a slab of concrete or indeed a slab of material, although this is preferred. The slab is preferably a solid body of material, which may but need not be a solid cuboid. However, the term "slab" as used herein is distinguished from a rigid wall, as described in EP0805746, for example.

Furthermore, the moving mould section 3 need not comprise a hood 30 with a concave chamber 31, although this is preferred as it facilitates the accommodation of a variety of configurations of the moulding surface 22. As outlined above, the concave shape of the chamber 31 enables the deformable wall 35 to retract into the hood 30, thereby inhibiting any damage that could occur as a result of, for example, projections 22a of the moulding surface 22. In fact, it is expressly envisaged that the chamber 31 may be described mostly or even entirely by an expandable deformable wall 35, which may be in the form of a bladder or tubular vessel (not shown). This may be useful, for example, in forming tubular components (not shown), wherein the tubular vessel is received within a cavity described in the slab 21.

The heating fluid supply sub-system 4 need not include two pumps 44, 45. It may, for example, include only a feed pump 44 and may, but need not, include a control valve for controlling the pressurisation of the chamber 31. The heating fluid used may comprise an oil or any other suitable medium, although the heating fluid is preferably hydraulic. The hydraulic cylinders 50 may also be replaced with any suitable means for moving the hood 30 or any element used in place of the hood 30, as described above. Additionally or alternatively, it is also envisaged that the slab 21 may be movable relative to the hood 30, in which case such hydraulic cylinders 50 or other means may be configured to cause the slab 21 to move relative to the hood 30 instead of or in addition to the arrangement described above and shown in the drawings.

It will also be appreciated by those skilled in the art that any number of combinations of the aforementioned features and/or those shown in the appended drawings provide clear advantages over the prior art and are therefore within the scope of the invention described herein.

Claims

CLAIMS1. A moulding system comprising a slab or block with a moulding surface formed thereon or therein, a chamber mounted opposite the moulding surface, which is at least partially described by a deformable wall and fluid supply means connected to the chamber for supplying a pressurised heat transfer fluid thereto, wherein the system is configured to control, in use, the volume and/or pressure of pressurised heat transfer fluid supplied to the chamber by the supply means in order to cause the deformable wall to heat or cool and force a mouldable material against the moulding io surface.
2. Moulding system according to claim 1 comprising a hood describing a concave depression with an open side described by a periphery of the hood, wherein the deformable wall is sealingly secured about the periphery of the hood such that the chamber is described therebetween.
3. Moulding system according to claim 2, wherein the fluid supply means comprises one or more pumps fluidly connecting the chamber to a reservoir and a heating element for heating the fluid supplied to the chamber.
4. Moulding system according to claim 3, wherein the one or more pumps comprise a first pump fluidly connecting an inlet of the chamber to the reservoir and a second pump fluidly connecting an outlet of the chamber to the reservoir, the system being configured to operate, in use, the first and second pumps individually to control the volume and/or pressure of pressurised heat transfer fluid supplied to the chamber.
5. Moulding system according to claim 4, wherein the system is operable to generate a negative pressure within the chamber such that at least part of the deformable wall retracts into the hood.
6. Moulding system according to any one of claims 2 to 5 comprising a frame or platen within or on which the slab or block is removably received, wherein the hood is movable, in use, relative to the frame or platen from an open position in which it is spaced from the moulding surface to a closed position in which the periphery of the hood surrounds the moulding surface.
Moulding system according to claim 6, wherein part of the deformable wall is clamped between the periphery of the hood and the slab, block, frame or platen when the hood is in the closed position.
Moulding system according to claim 6 or claim 7, wherein the slab or block comprises a concrete material.
Moulding system according to claim 1, wherein the chamber is described by a resilient tubular member, the slab or block comprising a hollow portion describing the moulding surface within which hollow portion the tubular member is received, in use.
Moulding system according to any preceding claim, wherein the deformable wall comprises an elastomeric material.
Moulding system according to any preceding claim comprising a controller operatively connected to sensors for sensing a pressure and a temperature of heat transfer fluid within the chamber, wherein the controller is configured to control the fluid supply means in response to a pressure and/or temperature sensed by the sensor(s).
A method of moulding a composite article, the method comprising placing a mouldable material between a moulding surface on or in a slab or block and a deformable wall of a chamber mounted opposite the moulding surface, supplying pressurised heat transfer fluid to the chamber in order to cause the deformable wall to heat and force the mouldable material against the moulding surface and allowing at least part of the mouldable material to solidify or cure.
13. Method according to claim 12 comprising supplying pressurised heat transfer fluid from a reservoir to the chamber at a first rate and discharging heat transfer fluid from the chamber to the reservoir at a second rate that is lower than the first rate to cause the deformable wall to compress and heat the mouldable material against the moulding surface. 7. 8. 9. io 10. 11. 12.Method according to claim 12 or claim 13 comprising retracting at least part of the deformable wall into a cover which partly describes the chamber after at least part of the mouldable material is solidified or cured.Method according to claim 14 comprising supplying pressurised heat transfer fluid from the or a reservoir to the chamber at a first rate and discharging heat transfer fluid from the chamber to the reservoir at a second rate that is higher than the first rate to retract the deformable wall or part thereof.Method according to claim 14 or claim 15, wherein the deformable wall is retracted at least part before the mouldable material is completely solidified or cured.Method according to any one of claims 12 to 16, wherein the moulding surface is defined by an unheated slab or block of material.Method according to any one of claims 12 to 17 comprising forming a moulding surface in or on a slab or block of concrete to provide the moulding surface.Method according to claim 17 or claim 18, wherein the moulding surface is formed in or on the slab by machining. 14. 15. 16. 17. 18. 19.