A SPORTS BOARD AND METHOD OF MANUFACTURE Field of the invention The invention relates to a novel structure for a board for sporting activities, together with its method of manufacture. The board may be especially suitable for use in watersports. The board can take the form of a surfboard, kiteboard, paddleboard or other type of board for use in a sporting or recreational activity. The invention is particularly advantageous to improve the durability and overall performance of the board.

Background to the invention

Boards or crafts are essential equipment for participation in various sports. In particular surfboards, kiteboards and paddleboards are each used within their associated watersports. Although the boards used in different sports have varying requirements (for example, in terms of shape, weight and size), the boards share common structural features and are designed to achieve high performance in use.

Equipment used in watersports such as surfing, or kiteboarding must be able to withstand considerable forces. These forces may be applied to the board in a predictable fashion (for example, by the surfer standing on the board), but may also be experienced in a less predictable way (for example, when in use and in contact with waves and currents within the water). The boards used in these sports must maintain levels of rigidity and durability to withstand the applied forces without suffering from breakage or deformation. Moreover, the overall performance of the board is determined by factors that are inherent to the structure and assembly of the board, for example, weight, buoyancy, shape and structural flexibility.

Commonly, boards are constructed with a lightweight core encased by a more durable outer shell or covering. An example of a prior art board 10 is shown in FIGURE 1A, 1 B and 1 C. The core of the board commonly comprises a solid lightweight foam 12 and the outer shell often consists of layers of resin composites 16 (such as fiberglass, Kevlar or carbon fibre) or a dense and durable foam 14. The lightweight foam core 12 is designed to provide buoyancy and the outer shell 14, 16 is intended to impart strength and to maintain the intended shape of the board. In addition, the outer shell provides a watertight seal to the core in order to prevent absorption of water by the lightweight foam. In general, the requirements to maintain good buoyancy, reduce weight, and to increase flexibility of the core must be balanced against the wish to maximise the strength of the outer shell. Maximising the volume of lightweight foam in the core improves buoyancy, whilst extra layers of composite fabrics or high-density foam in the outer shell helps increase strength (although at the expense of additional weight). Increasing buoyancy and reducing weight increases the speed and overall performance of the craft in use. However, improving the strength and rigidity of the outer shell improves the longevity of the board and maintains the optimised shape for high performance.

A problem experienced by existing boards is that the load of the rider is not evenly distributed across the board structure. For example, a user of a surfboard, when standing on the board, exerts the force of their weight on the upper surface of the outer shell beneath their feet (marked 18 at FIGURE 1 A). This may cause distortion of the upper shell, which compresses the lightweight foam (with low compression strength) beneath, as shown at FIGURE 1 C.

Bending and distortion of portions of the outer shell causes the shape of the board to be modified and the overall performance of the craft to be compromised. As a result, there is increased risk of a catastrophic failure of the board (irreparable warping, or even snapping). Furthermore, the forces applied to the board can cause small stress fractures in the outer shell and as a result, the outer shell is no longer watertight and the foam core can absorb water. This increases weight, and can also cause degradation of the foam core and delamination of the outer shell.

At present, manufacturers of such boards attempt to overcome these problems by adapting the board structure in a number of ways. In some cases, the outer shell is thickened, either by adding additional layers or by adding strengthened zones in the shell at the positions where the user will most often exert a force (the compression zone).

Alternatively, the core of the craft may be modified. In one example, the core includes a rigid internal skeleton defining the shape of the board and around which the outer shell is formed. In another example, the core is altered to comprise a compression zone formed of a block of a robust, high density foam (making up around one third of the total volume of the core). However, all of these modifications increase weight, reduce flexibility and consequently diminish overall performance. Summary of the Invention

Against this background, there is provided a board for use in sports, together with its method of manufacture. In particular, the board is for use in any type of watersports such as surfing, kitesurfing, kiteboarding and paddleboarding. The board comprises an inner core, enclosed by an outer shell. The inner core comprises reinforcement sections extending between the inner surfaces of the outer shell, with a buoyant material arranged around or between the reinforcement sections. The buoyant material may form a much greater proportion of the total volume of the core than the reinforcement sections. The reinforcement sections may comprise resin pillars or sections of a resilient material such as a resilient foam. The buoyant material may comprise a lightweight foam, being less resilient and having lower compressional strength than the reinforcing sections.

Alternatively, the buoyant material could be air or another gas contained by an

impermeable or airtight outer shell. The reinforcing sections may be concentrated in a portion of the inner core that is adjacent or beneath the regions of the outer core on which a user of the board exerts a force when the board is in use (in other words, the regions of the board at which the rider stands, known as the compression zones).

According to a first aspect of the invention there is provided a board for use in sports having an outer shell, comprising a deck and a hull defining a volume therebetween. The board further comprises a plurality of reinforcement sections arranged within the volume and extending between the deck and the hull, the remaining portions of the volume being at least partially filled with a buoyant material.

The board may be any type of board suitable for use in a sport, and in particular suitable for use in watersports. The board may have a depth that is much less than its length and width (in other words, the board take the form of a shaped panel or sheet). In the orientation in which the board or craft is commonly used, the upper surface is a deck upon which a user can ride during use. The lower surface may be a hull which in use may be in contact with or submerged under the water. Although the hull and the deck may be substantially planar, it may be shaped to improve the hydrodynamics of the hull.

A volume is defined by the outer skin in an interstice between the deck and the hull. The deck and the hull may be joined such that the volume is enclosed by the outer shell.

The outer shell or skin may be durable and preferably should provide a watertight, protective outer layer to the board. The outer layer may be stiff and relatively rigid, although not brittle or entirely inflexible. The reinforcement sections may provide a support structure within a core of the board, the core contained in the volume and enclosed by the outer shell. The

reinforcement sections may provide support to the outer shell. The reinforcement sections extend between the deck and the hull. In a first instance, the reinforcement sections may extend from the inner surface of the top portion of the outer skin, to the inner surface of the bottom portion of the outer skin. However, as an alternative, the reinforcement sections may extend from the deck, through the upper portion of the outer skin, and towards the inner surface of the bottom portion of the outer skin. Preferably (although not necessarily) the reinforcement sections will make contact with the inner surfaces of the outer skin. There may be at least two reinforcement sections, and preferably a greater number of reinforcement sections.

The remaining portions of the volume defined by the outer skin are at least partially filled with a buoyant material. The buoyant material may completely fill the portions of the volume which do not comprise the reinforcement sections, so as to be arranged between and adjacent to the reinforcing sections. Alternatively, the buoyant material may fill only some portions of the remaining volume, and some portions of the remaining volume may remain unfilled. The volume may be filled by more than one buoyant material, for example having first portions filled by a lightweight foam, and second portions filled with a gas (for example, to form air or gas pockets within the outer shell). The reinforcement sections may be separated and spaced apart within the volume such that buoyant material intervenes between each of the reinforcement sections.

Beneficially, the reinforcement sections represent only a small proportion of the volume defined by the outer shell. The remaining volume is occupied by at least one buoyant material (or may be occupied by more than one buoyant material). In a particular example, the reinforcement section may comprise less than 15% of the total volume defined by the outer shell. In an alternative example, the reinforcement sections may comprise less than 10% of the volume defined by the outer shell.

Advantageously, the buoyant material causes the board to be lightweight and buoyant, which improves the performance of the board in use. However, the reinforcing sections provide a supporting structure for the outer shell and act to distribute a load applied to the deck of the shell (for example, the weight of the rider when in use) across the outer shell. In particular, the load may be transferred through the reinforcing sections to be supported by the hull, such that the load is shared by both the deck and the hull of the outer shell. This decreases distortion of the outer shell, and reduces the likelihood of warping or damage to the board when in use. Preferably, the plurality of reinforcement sections comprises a plurality of pillars. For example, the reinforcement sections may comprise a plurality of columns, supports or posts. The pillars, columns or supports are elements that provide a structure to the board which transmits, through compression weight applied to the deck of the board to the rest of the hull. In a preferred embodiment the cross-sectional dimension of at least some of the pillars is less than the length of the pillars (the cross-sectional dimension being in an axis parallel to the plane of the board, and the length being in an axis that extends between the deck and the hull). However, some or all of the pillars may have a larger cross-sectional dimension than the length, especially at the tail end of the board where the length may be less than the width (due to the comparatively shallow depth of the board). For example, the reinforcing sections, may be cylinders, pucks or discs that have a cross-sectional diameter or dimension that is greater than its thickness or height. Preferably, the plurality of pillars will have a total volume much less than the volume occupied by the buoyant material. This allows the reinforcement structure to support the outer shell, without disproportionately increasing the overall weight of the craft. Beneficially a large number of narrow pillars may be arranged within particular regions or zones of the volume in order to provide a support structure beneath load bearing areas of the deck.

The cross-section of the reinforcing sections in the longitudinal direction of the board may have any shape. For example, the cross-section may be circular, rectangular, elliptical or hexagonal.

Preferably, at least one of the plurality of pillars has a length extending between the deck and the hull which is equal to or greater than a width in a direction orthogonal to the length. In other words, the dimension of at least one of the pillars in an axis extending from the deck to the hull is longer than the cross-sectional width or the diameter of the pillars in an axis parallel to the surface of the deck. Commonly, a number of the plurality of the pillars will have a length that is greater than its width. In some examples, at least half or in some cases a majority of the plurality of pillars demonstrate these dimensions. As such, different pillars within the plurality of pillars may have different dimensions compared to other pillars in the plurality. In a particular embodiment, pillars within a first, central portion of the board have a length greater than their width. However, in a tail portion of the board the pillars have a width than is greater than or equal to their length.

Advantageously, the volume of the pillars is small compared to the volume occupied by the buoyant material. In particular, in a region of the volume directly beneath the area of the deck at which the rider is positioned during use (a compression zone), the cumulative volume of the reinforcement sections will be equal to or less than 50% of the total volume of the compression zone. For instance, specifically in the region of the core of the craft to which a force is exerted during use, the reinforcement sections comprise half or less of the total volume of this region of the core. In general, at least in the centre portion of the board, the total volume of the reinforcement sections in the compression zones is less than the total volume of buoyant material in the compression zones. As such, additional weight from the pillars is minimised but the overall flexibility of the board is maintained.

Furthermore, the pillars provide a robust structural support for the outer shell.

Beneficially, each pillar of the plurality of pillars is spaced apart from each other pillar of the plurality of pillars. In other words, the pillars are separated within the volume, and are not directly connected to each other. The portions of the volume intervening the pillars may be filled or partially filled with buoyant material (such as a lightweight foam or a gas). The spacing between pillars is sufficient to provide adequate support to the outer shell when the board is in use, whilst keeping the number of pillars within the volume to a minimum in order to avoid unnecessary weight. For instance, in the compression zone (as defined above) the spacing between reinforcement pillars or columns may be equal to or greater than the width of the pillar or column. The spacing between pillars may be regular and consistent, or may be irregular such that some portions of the volume contain a greater concentration of pillars having smaller spacing than in other portions of the volume.

Beneficially, use of pillars that are separate and spaced apart from each other provides greater torsional flexibility in the board overall, which can have an advantageous effect on the overall board performance.

Advantageously, the buoyant material is a solid buoyant material. Preferably, the buoyant material is a solid resilient material which is lightweight and relatively low density. Use of a solid buoyant material provides some support for the outer shell, and assists to maintain the overall shape of the outer shell. Use of a lightweight solid buoyant material minimises the weight of the craft and increases buoyancy, thereby improving the performance of the board in use.

Preferably, the buoyant material is a foam. The foam may be an open cell foam or a closed cell foam, and is preferably lightweight. The foam may be compressible and allow elastic deformation but should maintain its shape in the absence of an applied force. The foam may be a polymer such as polystyrene, EPS, polyurethane, or PU. Advantageously, foam provides a lightweight and buoyant material which supports the shape of the outer shell. Alternatively, the buoyant material is a gas. For example, the buoyant material may be air or another gas which is contained within the outer shell. The outer shell may be impermeable so that the gas is trapped within the outer shell.

Preferably, the reinforcement sections are formed of a resilient material having a greater density and/or resilience than the buoyant material. Ideally, the reinforcement sections are formed of a resilient material having a greater compressive strength than the buoyant material. In other words, the reinforcement sections may exhibit less compression under a given force than the buoyant material. As such, the reinforcement sections compress less than the buoyant material alone when a user's weight is applied to the deck of the board. Beneficially, although the reinforcement sections may exhibit some elastic compression, they do not substantially deform when a force is applied to the outer skin in normal use. Therefore, the reinforcement sections support the outer skin and allow a load on the deck of the craft to be distributed across both the hull and the deck.

The reinforcement sections may be formed of a foam, a resin or a resin composite. For example, the reinforcement sections may be pillars of a dense foam, or may be pillars of a resin or resin composite. A resin composite may include composites such as a resin with glass microparticles, or Q-cell. The reinforcement sections may be secured or fixed in the buoyant material (using a fixing means such as an adhesive). A resulting inner core of the board may comprise the buoyant material having integral reinforcement sections. The reinforcement sections may be formed of a non-metallic material, and in particular may be formed from a material selected from the following group: foam rubber; vinyl foam;

polystyrene; PVC foam; resin; composite resin; polyurethane; expanded polypropylene (EPP); hardened plastics; wood; aluminium; Airex; carbon fibre; Kevlar. However, this list is not exhaustive, and other suitable materials may be used. Such materials provide reinforcement sections that are resilient but also relatively lightweight.

Ideally, the plurality of reinforcement sections extends between a rider position on the deck to the hull. For example, the rider position can be understood to be the region of the deck on which the user or rider of the board stands or applies their weight during use. The reinforcement sections may be concentrated in the regions of the volume adjacent to the rider position on the deck. The volume beneath the region of the deck on which the user applies their weight during use of the board may be defined a compression zone. In a surfboard, the compression zones may be located in a central portion of the board, as well as close to the tail of the board. The compression zone may make up to one third or one quarter of the total volume of the board. Preferably, a greater density of reinforcement sections are distributed in a compression zone compared to other regions of the volume. Advantageously, this allows the proportion of the volume containing the reinforcement sections to be minimised whilst maintaining the strength of the board and avoiding distortion. In one instance, the reinforcement sections may make up 50% or less of the total volume of the compression zone.

Optionally, the plurality of pillars comprises a plurality of hollow pillars defining a bore extending therethrough. For example, the pillars may be tubes and may be formed of a polymer or resin. Beneficially, use of hollow pillars may provide the supporting and strengthening properties of the reinforcement sections, whilst minimising the effect of additional weight introduced by the material of the reinforcement sections.

The bore of the hollow pillars may contain a resilient material. Preferably, the resilient material has a greater compressive strength than the buoyant material. For example, the reinforcement section may be a resin or polymer tube containing within its bore a section of foam having a higher density than the buoyant material. Such a configuration for the reinforcement sections may increase the compressive strength of the reinforcement section.

Alternatively, the bore of the hollow pillars may contain a section of the buoyant material. In other words, the reinforcement sections may be tubes inserted or implanted into the buoyant material. The tubes could be, for example, a solid polymer tube, or could be formed in-situ using a thermoset resin. Beneficially, this may provide a durable and resilient support structure for the outer shell, whilst minimising the overall weight of the craft. In a further example, the bore of hollow pillars may be filled with a gas such as air.

Advantageously, the outer shell is arranged to provide a watertight seal of the volume. In other words, the outer shell provides a sealed skin which encloses the volume. Beneficially, this prevents the buoyant material and/or reinforcing sections absorbing water, which would increase the weight of the craft and decrease its performance.

Preferably, the outer shell comprises a plurality of layers. Use of a plurality of layers in the outer shell allows incorporation of different materials into the outer shell. For example, the layers may be used to optimise the properties of the outer shell. In one instance, a first layer may be directed towards maximum durability and strength, with an outermost layer directed to reducing friction or water resistance.

At least one of the layers of the plurality of layers may comprise a reinforced composite resin. Preferably, the outer shell comprises at least one material selected from the following group: a high density foam; polystyrene; polyester; epoxy; fiberglass; carbon fibre; Kevlar; a para-aramid synthetic fibre composite; self-reinforcing polypropylene (srPP) fabric. However, this list is not exhaustive, and other suitable materials may be used. Beneficially, the layers are selected to provide a lightweight but strong shell or skin. In particular, materials having a high tensile strength-to-weight ratio may be advantageous.

Preferably, the board is for use in watersports. The board is suitable for use in any watersport in which a board is used for participation in the sport. In particular examples, the described structure relates to a surfboard, a paddleboard or a kiteboard. The board may relate to any type of equipment used to participate in a watersport.

According to a second aspect there is provided a method of manufacturing a board for use in sports, the method comprising forming a body of a buoyant material, forming a plurality of reinforcement sections extending through the body and forming an outer shell to enclose the body and reinforcement sections.

Preferably, the step of forming a plurality of reinforcement sections extending through the body comprises forming a plurality of pillars extending through the body. For example, the reinforcement sections may comprise a plurality of columns, supports or posts.

Advantageously, at least one of the plurality of pillars each has a length extending between the deck and the hull which is the same or greater than a width in a direction orthogonal to the length. In other words, the dimension of the pillar in an axis extending from the deck to the hull is longer than the cross-sectional dimension of the pillar in an axis parallel to the plane of the deck. Beneficially more than one of the plurality of pillars has a length that is greater than its width. In some examples, at least half or in some cases a majority of the plurality of pillars demonstrate these dimensions. This allows the pillars to comprise only a small proportion of the overall volume, whilst still providing a robust structural framework for the outer shell. In some instances, different pillars within the plurality of pillars may have different dimensions compared to each other. For example, the pillars in a portion of the volume beneath the centre or middle region of the deck may have a length that is greater than its width. However, in regions of the board having a lesser depth (for example, at the tail of the board), the length of one or more of the reinforcement pillars may be equal to or greater than the width. Ideally, in a region of the volume representing a compression zone, the cumulative volume of the reinforcement sections will be equal to or less than 50% of the total volume of the compression zone (in other words, the total volume of the reinforcement sections in the compression zones is less than the total volume of buoyant material in the compression zones).

Preferably, each pillar of the plurality of pillars is spaced apart from each other pillar of the plurality of pillars. Beneficially, the pillars are separate and not directly connected or attached to each other. The space intervening between the pillars may be filled or partially filled with the buoyant material. In a particular example, in the compression zone (as defined above) the spacing between reinforcement pillars or columns may be equal to or greater than the width of the pillar or column. Advantageously, providing the pillars to be spaced apart in the volume may minimise the proportion of the volume occupied by the pillars and so reduce weight, whilst also allowing greater torsional flexibility compared to a volume entirely comprised of the reinforcing material.

Preferably, forming a plurality of reinforcement sections comprises forming a plurality of bores through the body, and then forming a reinforcement section within each bore. For example, the body may be formed of a solid portion of the buoyant material.

Bores may be drilled or bored into or through the body of buoyant material. The bores may be an open bore or a blind bore. The reinforcement sections may be inserted or otherwise formed within the bores. For example, the reinforcement sections may form 'plugs' of material in the bores.

Optionally, forming a reinforcement section comprises filling each bore with a resin or resin composite. For example, the resin may be a thermoset material which is applied within the bore in a liquid form, and then allowed to set to become a rigid structure within the bore. As such the bore acts as a mould for the reinforcement section, and the reinforcement section can be formed to take any required shape.

Optionally, forming a reinforcement section comprises inserting a section of a resilient material into each bore. For example, columns, pillars or cylinders of a resilient material can be inserted into the bores. The resilient material may be formed to be constrained and secured within the bore, either by use of an adhesive or fixture, or by the compression of the resilient material to conform to the bore. In a particular example, a 'plug' of the resilient material is inserted into each bore to form the reinforcement sections.

Optionally, forming a reinforcement section comprises inserting a section of a resilient material into each bore and securing the resilient material to the body using a resin or resin composite. For example, a cylinder of resilient material can be inserted into the bore, the cylinder of resilient material having a cross-sectional width less than the diameter of the bore. In a void defined around the resilient material by the difference in dimensions, a resin or resin composite can be applied in liquid form. Once hardened, the resin or resin composite provides a tube surrounding the resilient material. The resilient material may be the same material as the buoyant material, or may be another material such as a high density, more resilient material. Forming a plurality of reinforcement sections may comprise punching ridged reinforcement sections through the body. In other words, the reinforcement sections may be pushed or pierced into the body from the outside. In one example, the reinforcement sections may be formed after forming of the outer shell around the body of buoyant material. In this example, the reinforcement sections may be pushed or punched directly through the deck of the outer shell and into the body. The reinforcement sections may extend through the deck and towards the hull of the outer shell (although ideally will not pierce the hull of the outer shell).

Preferably the reinforcement sections are formed of a resilient material having a greater density and/or resilience than the buoyant material. Preferably, the reinforcement sections are formed of a resilient material having a greater compressive strength than the buoyant material. Beneficially, the reinforcement sections compress less than the buoyant material when an equal compression force is applied.

Advantageously, the reinforcement sections are formed from a foam, a resin or a resin composite. The reinforcement sections may be formed of a material selected from the following group: foam rubber; vinyl foam; polystyrene; PVC foam; resin; composite resin polyurethane; expanded polypropylene (EPP); hardened plastics; wood; aluminium; Airex; carbon fibre; Kevlar. However, this list should not be considered exhaustive, and other suitable materials may be used.

Preferably, the buoyant material is formed from a foam. The foam may be an open cell or a closed cell foam which is lightweight and buoyant. This increases the overall buoyancy of the craft whilst minimising its weight.

Preferably, the outer shell comprises a deck and a hull and forms a watertight seal around the body and reinforcement sections. The outer shell may be a hard shell or skin formed around the body and reinforcement sections. The deck may be the uppermost surface of the board, with the lower portion of the outer shell forming the hull. Beneficially, the outer shell is watertight which prevents absorption of water by the buoyant material and reinforcement sections.

Advantageously, the outer shell comprises a plurality of layers. Different layers within the outer shell may be selected or optimised to provide different characteristics. For example, some layers may provide strength, whilst others may reduce friction of the craft in the water. The outer shell may comprise at least one material selected from the following group: a high density foam; polystyrene; polyester; epoxy; fiberglass; carbon fibre; Kevlar; a para-aramid synthetic fibre composite; self-reinforcing polypropylene (srPP) fabric.

However, this list is not exhaustive, and other suitable materials may be used. In a third aspect there is a surfboard, a kiteboard or a paddleboard having the structure described above or manufactured according to the method described above. Advantageously, these crafts have high strength and durability whilst maintaining relatively low mass and superior buoyancy. As such, the overall performance of the crafts may be improved.

According to a further aspect, there is provided a board blank with reinforcement sections or pillars added or incorporated according to any previously described aspect or feature. The board blank comprises the inner core only and does not have an outer shell, deck or hull. These board blanks may have the reinforcement sections (e.g. columns or any shape described in this disclosure or shown in the figures) that run the full thickness of the buoyant material (e.g. foam). Board blanks may be manufactured and supplied separately for finishing in further stages by different manufacturers. However, the board blanks may be supplied as a complete product.

Brief description of the drawings

A board and its method of manufacture in accordance with an aspect of the present disclosure is described, by way of example only, with reference to the following drawings, in which:

FIGURE 1 A is a cross-sectional view of a board according to the prior art;

FIGURE 1 B is a plan view of a board according to the prior art;

FIGURE 1 C is a schematic view of the forces applied in use to a board according to the prior art;

FIGURE 2A is a cross-sectional view of an example embodiment of the board according to the invention;

FIGURE 2B is a cross-sectional view of an example embodiment of the board according to the invention;

FIGURE 2C is a schematic view of the forces applied in use to a board according to the invention; FIGURE 3A is a cross-sectional view of a portion of an embodiment of the board;

FIGURE 3B is a plan view of a portion of an internal core of an embodiment of the board; FIGURE 3C is a schematic view of the steps for manufacture of an embodiment of the board;

FIGURE 4A is a cross-sectional view of a portion of a further embodiment of the board; FIGURE 4B is a plan view of a portion of the internal core of a further embodiment of the board;

FIGURE 4C is a schematic view of the steps for manufacture of a further embodiment of the board;

FIGURE 5A is a cross-sectional view of a portion of a still further embodiment of the board; FIGURE 5B is a plan view of a portion of the internal core of a still further embodiment of the board;

FIGURE 5C is a schematic view of the steps for manufacture of a still further embodiment of the board;

FIGURE 6 shows a schematic view of a selection of alternative cross-sectional shapes for portions of the internal core of the board;

FIGURE 7 shows a schematic and perspective view of a further alternative portion of the internal core of the board;

FIGURE 8 shows a plan view of two further example boards; and

FIGURE 9 shows a plan view of two further example boards.

Where appropriate, like reference numerals denote like elements in the figures. The figures are not to scale.

Detailed description of specific embodiments of the invention

Referring to FIGURE 2A, there is shown a cross-sectional view of the internal structure of a board 200 according to the invention. In this example, the board is a surfboard, having a depth which is small compared to the length and width of the board 200. The board 200 comprises a rigid outer skin 210. The upper surface of the outer skin is the deck 212 of the board (on which the user may stand when the board is in use). The lower portion of the outer skin 210 provides a hull 214 for the craft. In use, the outer surface of the hull 214 would be in contact with the water. The outer skin 210 is a sealed shell which defines a volume between the deck 212 and the hull 214. A number of reinforcement sections 216 are arranged within the volume. The reinforcement sections 216 are configured between the inner surfaces of the outer skin 210, so that they extend from the underside of the deck 212 to the inner surface or upper side of the hull 214. In this example, the reinforcement sections 216 make contact with the two inner surfaces of the outer skin 210.

The reinforcement sections 216 are columns or pillars having a cross-section (in a left-to-right direction in FIGURE 2A) which is narrow compared to their length extending between the two surfaces of the outer skin 210. In other words, the length of the pillars in an axis extending from the deck to the hull is greater than the width of the pillar in an axis parallel to the near planar surface of the deck.

A buoyant material 218, 220 is contained in the remaining portions of the volume. For example, a buoyant material is provided in the regions of the volume between the reinforcing sections 220, as well as in the volume at the nose and tail of the board 218. In the example of FIGURE 2A, the reinforcing sections 216 and the buoyant material 218, 220 together fill the volume defined by the outer skin 210. The reinforcement sections 216 are separated and spaced apart within the volume, such that the buoyant material 218 intervenes between each of the plurality of reinforcement sections 216 and surrounds each pillar or column of the reinforcing sections 216.

In the example of FIGURE 2A, the buoyant material 218, 220 is a lightweight foam.

The reinforcing sections 216 comprise a foam that is denser than the buoyant material 218, 220, and has much greater resilience than the buoyant material 218, 220 (in other words, the denser foam of the reinforcing sections 216 require a greater force to be compressed, compared to the lightweight foam of the buoyant material 218, 220). In this example, the reinforcing sections 216 are embedded into the buoyant material 218, 220, so that the reinforcing sections 216 have a length that is equal to the depth of the buoyant material 218, 220. In other words, the reinforcing material 216 and the buoyant material 218, 220 extend between the inner surfaces of the outer shell 210.

The reinforcing sections 216 are arranged in certain regions or zones in the volume defined by the outer skin 210. This is illustrated in FIGURE 2B which shows a cross- sectional view of the surfboard 200, looking down from above. The reinforcing sections 216 are arranged in a centre portion 220 of the board 200, and at portions 222 in the tail end or back of the board (according to the orientation of the surfboard in use). These are the areas or zones of the board on which the user or rider of the surfboard would stand or exert a force whilst in normal use (also known as a rider position). These portions 220, 222 of the board can be denoted compression zones (in other words, zones in which a compressive force is applied during normal use). In this example, the total volume of the reinforcement sections 216 in the compression zones is less than the volume of buoyant material in the compression zone.

In use, the rider stands or sits on the deck 212 of the surfboard 200 whilst the board is floating in the water. In normal use, the user will stand or sit so that they make contact with the surfboard 200 in the compression zones 220, 222. The user's weight exerts a downward pressure on the board 200. As an example, FIGURE 2C shows the board of FIGURE 2A with arrows illustrating the force applied by the weight of the user standing in the central compression zone.

The reinforcement sections 216 comprising a dense resilient foam, do not compress under the applied weight to the same extent as the buoyant material. As a result, the reinforcing sections provide a supporting structure for the upper surface of the outer skin (the deck 212). The reinforcing sections transfer the applied forces to the lower portion of the outer skin (the hull 214), which is directly in contact with the water. As a result, the upthrust or buoyancy forces of the water directly oppose the downward weight of the user, without the internal core being substantially compressed. Consequently, relatively little distortion occurs of the deck 212 or outer shell 210 of the surfboard.

Advantageously, the embodiment of the board described with reference to

FIGURES 2A, 2B and 2C allow for the majority of the volume or core of the craft to be formed from a low density material such as lightweight foam. Such a material results in a craft which demonstrates particularly good buoyancy and so better overall performance and speed when in use. Inclusion of the reinforcing sections (which represent a small proportion of the volume of the core of the craft compared to the buoyant material) maintains the structural integrity and provides structural support to the rigid outer shell of the board without adding excessive additional weight.

Although the reinforcing sections discussed above comprise a foam, the reinforcing sections may be provided in alternative forms. In each case, the reinforcing sections demonstrate a greater compressive strength and are more resilient than the buoyant material. FIGURE 3A shows a schematic representation of a portion of the cross-section of a board having reinforcing sections according to a first example. FIGURE 3B shows a plan cross-section of the same portion of the board. The dotted line in FIGURE 3A shows the axis of the cross-section illustrated at FIGURE 3B, and the dashed line in FIGURE 3B shows the axis of the cross-section illustrated at FIGURE 3A. In the example embodiment of FIGURE 3A, the outer shell 210 comprises a plurality of layers, each comprising different materials arranged to strengthen the shell. The upper, outer surface of the outer shell is the deck 212 of the craft, and the lower portion of the outer shell forms the hull 214 of the craft. A volume within the outer shell 210 contains a buoyant material 320, which in this case is lightweight foam. Reinforcement sections are formed within the buoyant material 320 by the provision of channels or columns of resin composite 322. After manufacture, the channels of resin composite 322 form rigid pillars in the buoyant material 320. In this example, the resin composite is a resin incorporating glass microspheres such as Q-cell resin filler.

The resin composite pillars 322 exhibit a much greater compressive strength than the lightweight foam used for the buoyant material 320. This means that, in use, when a compressive force is applied to the board, the resin composite pillars 322 provide a resilient structure or frame within which the lightweight, buoyant material 320 is arranged. A load applied at the deck 212 of the board is transferred through the resin composite pillars 322 to the hull 214 of the craft, thereby distributing the applied force across the outer shell 210 and the core of the board. As a result, there is significantly less distortion and greater durability of the board when in use.

FIGURE 3C illustrates the steps for manufacture of the reinforcing sections of FIGURES 3A and 3B. In a first step (a), the body 320 of the board is formed by shaping a portion of buoyant material. For example, the body 320 could be formed by carving, moulding or otherwise shaping the buoyant material into a suitable profile or shape for the board. At a step (b), bores 324 are formed in the body 320 of buoyant material. The bores or hollow cavities 324 are drilled or bored so as to extend through the body 320 of the board. In the example shown, the bores 324 extend through the full depth of the body 320.

The reinforcement sections 322 are formed in the body at step (c). The

reinforcement sections 322 comprise a resin composite, which is injected or extruded into the bores 324 formed within the body 320. The resin composite may be a thermoset material, and so be injected into the cavity as a liquid and allowed to harden to solid pillars 322 within the bores.

In a final step (d), an outer skin or outer shell 210 is applied to enclose the buoyant material 320 and reinforcement sections 322. The outer skin 210 may provide a sealed, watertight shell to the inner core of the board. In some cases, the body 320 may be further shaped prior to application of the outer skin 210.

Board "blanks" may be formed using a mould (e.g. formed from concrete). A liquid foam or other material is poured into the mould, which undergoes a reaction (e.g. with air) and expands to fill the mould. The blank is shaped using a saw (e.g. band saw) or other tool. The blank may be cut down the middle (e.g. long or short axis) so that a wooden or other stringer may be added to allow different types of flex (e.g. parabolic or linear). In other embodiments, no stringer is added and the blank is not cut down the middle.

The blanks may be cut to shape (e.g. using a CNC machine). Bores or holes are cut or drilled through the board to allow for the reinforcement sections to be added. These reinforcement sections are pushed or plugged into the bores (either by hand or machine) and are fixed by an interference fit, adhesive or mechanically. The boards may be machined to provide a smooth or level surface (i.e. the reinforcement sections are levelled with the top and/or bottom surface of the board). The blanks may be further worked to provide a complete board or sent away for further manufacturing.

In an alternative example, the reinforcing sections make take a different form. FIGURE 4A shows a schematic representation of a portion of the cross-section of a board having reinforcing sections according to a second example. FIGURE 4B shows a plan cross-section of the same portion of the board. The dotted line in FIGURE 4A shows the axis of the cross-section illustrated at FIGURE 4B, and the dashed line in FIGURE 4B shows the axis of the cross-section illustrated at FIGURE 4A.

As in the example described above, the outer shell 210 in FIGURE 4A includes a plurality of layers, for example including a fiberglass layer and a dense foam layer. The upper surface of the outer shell represents the deck 212, and the lower portion of the outer shell forms the hull 214 of the craft. The volume between the deck 212 and the hull 214 represents the core of the craft. In this example, the core comprises a buoyant material 420 which is a lightweight foam. The reinforcement sections are formed by columns or inserts of foam 422 having a much higher density and resilience than the buoyant material 420.

As shown in FIGURE 4B, the columns of resilient foam 422 in this example have a square cross section. Each column 422 is inserted or embedded into the buoyant material 420, the reinforcement sections 422 being integral within a core of the buoyant material 420. Although not shown in FIGURE 4A or 4B, the columns or inserts of resilient foam 422 may be fixed or secured to the buoyant material 420 using an adhesive or resin.

In use, the resilient foam columns 422 support the deck of the craft when a downward force is applied. The load is shared between the hull 214 and deck 212 of the outer shell, as well as the core. As the core cannot compress to the extent that would be observed in the absence of the resilient foam columns, the distortion of the outer shell is reduced. FIGURE 4C illustrates the steps for manufacture of the reinforcing sections of FIGURES 4A and 4B. In a first step (a), the body of the board 420 is formed by shaping or moulding a portion of buoyant material. At step (b) bores or cavities 424 are formed or prepared in the body 420 of buoyant material. In the example shown, the bores 424 extend through the full depth of the body 420, although the bores could be a blind bore.

At step (c), reinforcement sections are formed by insertion of a section or portion of resilient material 422 into each bore 424. In this example, a column or pillar of dense foam 422 is inserted into the bore 424. The column or pillar of foam 422 is secured in the bore 424 using an adhesive or fixing agent.

Finally, an outer skin or outer shell 210 is formed at step (d) to enclose the buoyant material 420 and reinforcement sections 422. The outer skin 210 may provide a sealed, watertight shell to the inner core of the board. In some cases, the core may be further shaped prior to application of the outer skin. FIGURES 5A and 5B illustrate a further example of the reinforcing sections.

FIGURE 5A shows a schematic representation of a portion of the cross-section of a board having reinforcing sections according to a third example. FIGURE 5B shows a plan cross- section of the same portion of the board. The dotted line in FIGURE 5A shows the axis of the cross-section illustrated at FIGURE 5B, and the dashed line in FIGURE 5B shows the axis of the cross-section illustrated at FIGURE 5A.

In this example, the outer shell 210 includes a plurality of layers. The uppermost surface of the outer shell is the deck 212 and the lower portion of the outer shell forms the hull 214. The core of the craft is formed within the volume defined by the outer shell. 210 The core comprises a buoyant material 520 such as a lightweight foam. The core further comprises reinforcing sections formed by pillars or tubes 522 of a resin. Sections of a resilient material 524 are inserted into the bore or centre of the tube, so as to be surrounded by the resin tube 522. The resilient material 524 may have a greater compressive strength than the buoyant material 520 within the core, although in an alternative form the sections of the resilient material may be the buoyant material (for example, the lightweight foam. In a still further example, the tubes are hollow and define an air filled void. Advantageously, use of tubular pillars as the reinforcing sections provides a structure or framework of rigid, resilient tubes for reducing compression of the core, whilst minimising the weight of the board.

FIGURE 5C illustrates the steps for manufacture of the reinforcing sections of FIGURES 5A and 5B. In a first step (a), the body 520 of the board is formed by shaping or moulding a portion of buoyant material. At step (b) bores or cavities 526 are formed or prepared in the body 520 of buoyant material. In the example shown, the bores 526 extend through the full depth of the body 520, although the bores could extend only part way through the body.

At step (c), reinforcement sections are formed by insertion of a section or portion of resilient material 524 into each bore 526. In this example, the resilient material 524 is a column or pillar of dense foam. The column or pillar of resilient material 524 has a cross- section that is less than the cross-section of the bore 526. As a result, once the resilient material is inserted into the bore, a void 528 is defined surrounding the resilient material 524, between the pillar of resilient material 524 and the buoyant material 520 in a radial direction. At step (d) the void 528 is filled with a resin or resin composite to form a tube or hollow pillar 522 of the resin or composite around the resilient material 524. The resin or resin composite may be a thermoset material which is applied as a liquid and allowed to harden into a solid tube 522.

At step (e), an outer skin or outer shell 210 applied to enclose or surround the buoyant material 520 and reinforcement sections 522, 524. The outer skin 210 may provide a sealed, watertight shell.

Many combinations, modifications or alterations to the features of the above embodiments will be readily apparent to the skilled person and are intended to form part of the invention.

The board described is intended for use in sports. The board may be suitable for use in any sport which uses a board as equipment to participate in the sport. In such sports (whether water or land based) the boards are required to demonstrate high performance, in particular being durable and lightweight. The board may be useful where the compression or distortion of the shape of the board would reduce performance.

Example of land based sports in which the board could be used includes kite ski boarding, kite land boarding, snowboarding, tobogganing, or other activities.

The board may be particularly suitable for use in water sports. In particular examples, the board may be a surfboard, paddleboard or kiteboard. The elements of the structure of the board described above in reference to FIGURES 2A to 5C may equally be applied to the structure of any type of board for use in watersports.

As described in a number of the above embodiments, the outer shell may comprise a plurality of layers. For example, the plurality of layers may comprise any combination of one or more layer of any type of suitable material. Examples of possible materials include (but are not restricted to) dense foam, Kevlar, fiberglass, carbon fibre, polystyrene, polyester, epoxy, a para-aramid synthetic fibre composite or self-reinforcing polypropylene (srPP) fabric, or. In other embodiments, the outer shell could be formed from a single layer, and comprise only one type of material.

Although in the description above the outer shell is described as having an upper deck and a lower hull, the skilled person would understand that this does not limit the orientation of the board. Furthermore, the outer shell may be formed as a single skin, or may be formed by joining an upper portion of the outer shell with a lower portion of the outer shell (in other words, the shell may be formed as more than one part, or as a single part). In each embodiment, the outer shell is preferably robust and watertight, and will be relatively stiff in order to maintain a predefined shape. However, the outer shell will allow for some flexibility of the board overall.

The reinforcement sections described in each embodiment above are formed of a resilient material, having greater compression strength than the surrounding buoyant material. The reinforcement sections may be formed of a resin, a resin composite (such as Q-cell, or a resin mixed with other solid particles or with fibres) or a type of polymer. The reinforcement sections may be formed of a solid foam that is open or closed cell (for example, polystyrene). Examples of possible materials for the reinforcement sections include foam rubber, vinyl foam, polystyrene, PVC foam, resin, composite resin, polyurethane, expanded polypropylene (EPP), hardened plastics, wood, aluminium, carbon fibre, Kevlar or Airex.

The reinforcement sections described herein are shown as a plurality of pillars formed within the volume and extending between the inner surfaces of the outer shell. Although the pillars illustrated have a narrow cross-section or diameter (parallel to the plane of the board) compared to their length (in the axis extending between the surfaces of the outer shell), the pillars may have any dimensions. Each pillar of the plurality of pillars does not necessarily have the same width or dimensions. For example, the pillars may each have a larger cross-section than length, and may occupy a greater proportion of the volume than shown in the accompanying figures. In most cases, the reinforcement sections will occupy a smaller proportion, and even a much smaller proportion, of the volume than the buoyant material. In a particular example, the reinforcement sections occupy less than 15% of the volume defined within the outer shell. In a further example, the reinforcement sections occupy less than 10% of the volume defined within the outer shell. However, this is not necessarily the case. Although FIGURE 2B shows the reinforcement sections in all the compression zones 220, 222 as having a length that is greater than their width, this is not necessarily the case. For example in some boards (such as a surfboard), the compression zones at the tail end may have a width that is equal to or greater than their length. This is because the overall depth of the board in this region is much less than in the centre portion of the board. In general, within the compression zones of the board the cumulative volume of the reinforcement sections will be less than the total volume of the buoyant material.

Although the reinforcement sections described herein are shown as pillars having a circular or square cross-section, any shape of cross-section for the reinforcement sections could be used. For example, an elliptical, a hexagonal, a rectangular or any shape of cross-section could be applied. In a particular example, a hexagonal cross-section is used. As described above, the reinforcement sections may comprise solid pillars, or may comprise hollow pillars having a cavity filled with another material. Where hollow pillars are used as the reinforcement sections, the cavity through the pillars may be filled with the buoyant material, with air or another gas, or with another material (such as a dense foam).

The reinforcement sections in the accompanying figures are shown as being within the buoyant material, so as to extend to be conterminous and contiguous with the upper and lower surface of the buoyant material. In other words, the reinforcement sections are integral with the buoyant material so as to form a level and unbroken surface of the core of the craft. Alternatively, the reinforcement sections could be arranged so as not to extend to the upper and lower surface, or to extend slightly beyond these surfaces. In a further example, the reinforcement sections could be embedded or enclosed within the buoyant material.

The buoyant material may be formed from any number of materials. For example, the buoyant material could be a solid material, such as an open cell or a closed cell foam. In a particular example, the foam may be a polymer such as polystyrene. Preferably, the foam is lightweight and is chosen for optimal buoyancy. The buoyant material should be more compressible, or less resilient, than the material used for the reinforcement sections. Advantageously, the buoyant material has a lower density than the material from which the reinforcement sections are formed. For example, where a foam is used for both the reinforcement sections and the buoyant material, the foam used for the reinforcement sections will have a greater density than the foam used for the buoyant material. In other embodiments, the buoyant material could comprise a gas (for example, air) which is contained within a rigid, impermeable (or hermetically sealed) outer shell. In this circumstance, the reinforcement sections are arranged within the outer shell and the gaseous buoyant material fills the remaining portions of the volume.

The buoyant material is described as at least partially filling the remaining portions of the volume defined by the outer shell (in other words, portions of the volume not occupied by the reinforcement sections). Although in most cases, the buoyant material will fill all the remaining portions of the volume, this is not necessarily the case. For example, the buoyant material may be arranged in portions of the volume between the plurality of reinforcement sections, but other portions of the volume (for instance at the nose and tail of the board) could remain unfilled. Alternatively, the areas of the volume away from the compression zones of the board could contain the buoyant material, but the regions between the reinforcement sections could remain unfilled. The volume may contain more than one type of buoyant material (for instance, the reinforcement section, a first buoyant material such as a lightweight foam, and at least one other buoyant material such as air, or another gas).

In the embodiment described in FIGURE 2B, the reinforcement sections are shown as being arranged within regions or specific areas of the volume (the compression zones, where the user most commonly exerts their weight whilst the board is in use). However, the reinforcement sections could also be evenly distributed throughout the whole volume (in other words, across the area of the deck). Alternatively, the reinforcement sections could be concentrated at regions other than those shown in FIGURE 2B, or may be arranged in any other configuration. In the most beneficial arrangement, the reinforcement sections will be arranged beneath the deck of the craft in the regions of the board which will undertake the most force whilst the board is in use. Furthermore, the reinforcement sections may be spaced apart for each other within the buoyant material. For example, the reinforcement sections may be arranged so as to be spaced from each other by a distance much greater than the width of each reinforcement pillar.

The method of manufacture for the embodiments of the board described above may differ from those detailed. For example, although the method describes shaping the buoyant material and forming the reinforcement sections therein, the shaping of the core could take place at any time (for instance, after formation of the reinforcement sections). In some cases, the reinforcement sections could be formed first, with the buoyant material formed after. For example, the reinforcement sections could be arranged within a mould, and the buoyant material formed or injected around the reinforcement sections to form the core of the craft. Furthermore, although the method describes forming the outer shell as a final step in manufacture, the outer shell may be formed as an earlier step in manufacture. In one example, the core of buoyant material may be defined within the outer shell. The reinforcement sections may then be inserted into the core through the deck of the outer shell (in other words, the reinforcement sections may be pierced or punched through the outer deck). Using this method of manufacture, the reinforcement sections will extend through the core of buoyant material towards the hull of the outer shell, but should not penetrate the hull of the outer shell.

The reinforcement sections may take any form. Figure 6 shows a set of nine example cross-sectional shapes for the reinforcements sections. The reinforcement sections may have a constant cross-section or a variable cross-section (low to high, high to lower, greater in the middle, greater at the ends, etc.) Figure 7 illustrates a further alternative reinforcement section (frusto-conical or flared plugs). The larger area may be at the deck or hull-side of the board, for example.

Figure 8 shows further example reinforcement sections. Sections 810 are linear

(rectangular or bar-shaped cross-sections of the same or difference sizes). Sections 820 show circular, ring or toroidal cross-sections (rings within larger rings). Any number of rings, groups of rings (within each other) and separations between rings may be used. Boards may have the same reinforcement sections or more than one type (e.g. different on either side of the long centre-line according to any combination). For example, the boards may only have the rings or sections 820 or only the linear sections 810. The reinforcement sections may be place on either or both sides. This may provide custom flex options or for riding (and reinforcing) on one side only.

Figure 9 shows two further examples in which linear or rectangular reinforcement sections are arranged as chevrons or stripes at an angle. The chevrons on either side of the centre line of the board have opposing angles so that they face each other or form a series of "V" shapes (meeting each other or separated). The "V" may face the direction of travel or oppose the direction of travel, for example.

The boards may also be used for knee-boarding, wind-surfing and/or paddle boarding.

The buoyant material may be air. For example, the board may be formed from an inflatable material shell and the reinforcement sections may be placed within an air-filled cavity or series of cavities within the shell.

In one example implementation (used with any described board, blank or other feature), the reinforcement sections are fixed to or in direct contact with the deck and hull (or top and bottom skins) of the board but may be separated or not bonded to the buoyant material. There may also be a space around some or each of the reinforcement sections or columns. This allows a force on the deck or top to be more easily transmitted to the opposing deck or side. This can adjust the flex in the board or allow for other tuning. The water surface may affect the rocker or hull of a board. For example, as a rider pushes on the board, the force may be applied through the reinforcement sections or board column structures to the hull and through to the water surface. The water surface may then apply a force pushing back on the hull surface of the board.

In a further example implementation (used with any described board, blank or other feature), the reinforcement sections may be or incorporate resilient members or springs that provide a level of cushion, damping or spring-back.