STRUCTURAL ELEMENT OF A SLIDING BOARD AND MANUFACTURING METHOD

Description

Technical field

[0001] The invention relates to the field of board sports and in particular snow board sports. It relates more particularly to a method for manufacturing a structural element of a board whose core and / or edges are lightened while retaining high mechanical properties. Previous techniques

[0002] Generally speaking, a sliding board is composed of a lower assembly, including the sliding sole and at least one layer of mechanical reinforcement, fibrous or metallic, and an upper assembly also including at least one layer of mechanical reinforcement, fibrous or metallic on which the members for supporting the user's foot are installed. These two lower and upper assemblies are separated vertically by a layer forming the core, separating the mechanical reinforcements of these two assemblies relative to the neutral fiber.

[0003] The side faces of the board are generally equipped with elements called edges, forming the laterally visible area of ​​the structure, whose function is in particular to protect the core from external aggression, and in particular from mechanical impacts, or from water or snow infiltration.

[0004] To achieve this, the edges are generally made from a monolithic element, made of a relatively mechanically resistant material, such as acrylonitrile butadiene styrene (ABS). This edge element is interposed between the upper assembly and the lower assembly, and rests in particular on the metal edges bordering the sliding base. Thus, these edge elements also have the function of ensuring the good transmission of the forces exerted by the user from the upper face onto the edges of the board. This is why it is useful for these edge elements to be made of a material which has good resistance to vertical compression.It has already been proposed, for example in document FR 2 663 236, to give the edge elements a particular structure, possibly by integrating areas of a viscoelastic material, so as to ensure a possible integrating areas of a viscoelastic material, so as to ensure a certain damping of the vibrations passing from the edges to the upper face of the ski and in particular in the area where the user's foot rests. Such a device nevertheless remains massive, and contributes negligibly to the overall mass of the board. In addition, the areas including the viscoelastic material are made by recesses in the monolithic element.The area of ​​the edge element closest to the core thus exhibits, in terms of compression, the intrinsic behavior of the material constituting the bulk of the edge element, so that the compression of the viscoelastic material is observed almost exclusively near the outer face of the edge. A similar device is described in document FR 2 891 751.

[0005] The core's primary function of separating the reinforcements of the upper and lower assemblies from the neutral fiber requires that the core have a certain crush resistance to maintain this distance constant. This is why cores are traditionally made from incompressible materials, whether wood or expanded foam, occupying the entire volume separating the lower and upper spaces.

[0006] Since the core therefore occupies a predominant part of the volume of the board, attempts have been made to reduce its mass, in order to reduce the overall weight of the board. The main part of these solutions consists of using a blade with a wavy profile, which comes into contact with the upper and lower assemblies. An example is given in patent DE 2 047 705, which describes a lightweight ski core, formed by a blade of a metallic material, which is folded in the form of triangles. More precisely, the strip is folded in such a way that it comprises horizontal segments coming into contact with the horizontal segments of the adjacent triangular patterns. Such a core, although it has a reduced mass, has a disadvantage in that it deforms excessively when flexed, and that, for example, when the board is flexed upwards, the triangular patterns in contact with the lower assembly tend to move away from each other.A similar solution is described in JP-S52 147129 A. Similar solutions are described in US 6,502,849, in which the patterns of the folded blade are rectangular or trapezoidal. Other solutions are described in FR 2,536,335 and AT 387,331, which combine several wavy blades by superposition, leading to relative manufacturing complexity and limited weight savings. Document AT248306 also describes a core, made from the assembly of wavy structures, the crests of which are perpendicular to the sliding surface. Document FR2648721 describes a sliding board whose core incorporates a laminated layer comprising bosses aligned in two directions. Statement of the invention

[0007] One of the objectives of the invention is to lighten certain elements of the structure of a sliding board while retaining high mechanical properties, whether it is the crushing resistance and / or the bending stiffness of the board. Another objective of the invention is to provide structural elements whose mechanical properties are adaptable to the profile of the board, depending on the location of the areas having more or less stress to withstand.

[0008] To do this, the Applicant devised a manufacturing method according to claim 1 of a sliding board element, having a particular structure.

[0009] More specifically, this structural element of a sliding board is characterized in that it includes: a continuous lower wall and an upper wall, having a median longitudinal plane perpendicular to this lower wall, a set of joining portions distributed along the length of the structural element, these portions being separated by openings extending along the width of the structural element, each joining portion coming into contact with the lower and upper walls.

[0010] In other words, the invention consists of producing the structural element of the sliding board as an essentially openwork structure, formed of two substantially flat surfaces, at the level of the upper and lower faces of the element. These surfaces are connected by bridging zones, which delimit between them transverse passages along the width of the structural element, from one lateral face to the other.

[0011] These joining portions advantageously have a constant section, along planes parallel to the median longitudinal plane, corresponding for a ski for example to the vertical plane parallel to the long direction of the ski. In other words, each of the joining portions has a section of constant shape when moving in a direction perpendicular to the median longitudinal plane. These joining portions are preferably hollow, that is to say they define a volume free of material which extends from one lateral face to the other of the structural element.

[0012] In other words, the structural element according to the invention comprises two upper and lower skins, connected by spacers forming tubular zones, the shape of each of which is the same from one lateral face to the other of the structural element.

[0013] Thanks to this particularly openwork structure, the mass of the structural element is significantly reduced compared to traditional monolithic structural elements. However, this reduction in weight does not have a negative impact on the mechanical properties of the structural element, since the choice of materials constituting the joining portions, as well as their location, make it possible to optimize the crushing resistance of the part. In addition, the continuous architecture of the upper and lower walls, and the distribution of the joining portions between these two walls also ensure very good bending resistance properties.In fact, the upper and lower walls are considered continuous in the sense that they provide the mechanical connection between two successive joining portions, both on the top and bottom of the structural element, so as to form a structure whose upper and lower faces transmit the tensile or compressive forces experienced during bending movements. These walls can be solid or perforated as required.

[0014] The geometry of this structural element, with an identical section regardless of the longitudinal plane between the two lateral faces of the element, allows the latter to be manufactured easily, for example from an extruded profile, or even by three-dimensional printing techniques.

[0015] Multiple variants can be considered, developed and combined with regard to the geometry of the junction portions.

[0016] Thus, it is possible for adjacent junction portions to come into contact with each other, or conversely to be spaced apart from each other without contact. This makes it possible in particular to modulate the mechanical properties, in particular crushing resistance or weight reduction.

[0017] Thus, when the joining portions are in contact with each other, i.e., joined, the resistance to crushing and bending is greater than that of a structure with joining portions of the same geometry, but spaced apart from each other, i.e., not joined. On the other hand, this second structure is lighter. A compromise must be found depending on the objectives sought in terms of mechanical properties and weight reduction. Obviously, it is possible to mix these two types of geometry within a structural element, for example to significantly lighten the portions least subject to mechanical stress, or on the contrary to reinforce the mechanical properties of the most stressed areas.

[0018] The geometric shape of the joining portions can also be varied. Thus, the joining portions can have a polygonal shape, in particular a triangular or even a rectangular shape. Thus, depending on the inclination of these segments forming the joining portions, it is possible to adjust the mechanical properties of the structural element. Alternatively, it is possible for the joining portions to have a curved region, or even to be completely circular in shape. Curved or even circular joining portions have the advantage of providing a certain elasticity with respect to vertical compression phenomena.

[0019] Obviously, the structural element can have a constant thickness along its entire length, and therefore parallel lower and upper walls. But it is also possible for the thickness of the structural element to be adapted to the variation in thickness of the board along the area where the structural element will be added, in which case the distance separating the lower and upper walls of the structural element is variable along the length of the latter. In the latter case, the dimensions of the joining portions can be adapted to the variation in the thickness profile. It is also possible for the upper wall to be inclined relative to the lower wall so that the thickness of the structural element is less on its external lateral face than on its internal lateral face. In this case, the dimensions of the joining portions, or even their shape, vary across the width of the structural element, from one lateral face to the other.Thus, the junction portions may have a circular section of decreasing diameter towards the outside of the structural element, and form a truncated cone, or have a circular section on the internal face of the structural element, which evolves into an elliptical section near the opposite face.

[0020] In a particular embodiment, the structural element is covered by a closing wall. This closing wall may be an upper wall, for example in the case where the structural element is a core, or a side wall in the case of an edge element. In the latter case, the wall is then substantially parallel to the median longitudinal plane, that is to say extending from the lower wall to the upper wall while covering the joining portions. In the case where the structural element is an edge element, this closing side wall may be intended to prevent the entry of snow when it is located on the visible face of the structural element, or to isolate the structural element from the core, in particular when it is made of injected material, on the opposite side face.

[0021] In practice, the structural element can be a core or an edge element. Both types of structure must have good compressive and bending resistance properties.

[0022] The invention relates to a manufacturing method for producing such a structural element and more specifically to an additive manufacturing method, also known as 3D printing. According to the invention, additive manufacturing consists of depositing material layer by layer, the layers being stacked on top of each other either in the direction of the width of the structural element or in the direction of the thickness of the structural element.

[0023] In other words, this process allows all or part of the structural element to be produced through successive deposits.

[0024] Given the specific geometry of the structural element according to the invention, and the fact that the latter has through openings between its two lateral faces, an additive manufacturing process is carried out by deposition on a plane corresponding to one of the lateral faces of the structural element. To do this, this face, which will be intended to be vertical during integration into the board, rests on a horizontal plane to allow the growth of the height of the part during the deposition of the material, up to a plane, more generally a surface, which will form the opposite lateral face.

[0025] According to an advantageous variant, the method comprises a step of depositing a continuous one-dimensional fibrous element to form successive layers superimposed in a direction perpendicular to the median longitudinal plane. In other words, the material which is deposited during the method includes a wire or a ribbon of small width without any discontinuity, preferably of a material of high tenacity such as glass, carbon or certain natural fibers. This material is deposited in the planes parallel to the future lateral face of the structural element, that is to say planes parallel to the future median longitudinal plane of the structural element.

[0026] In a particular embodiment, a one-dimensional fibrous element, impregnated with a hardenable resin, is deposited on a reference plane parallel to the median longitudinal plane of the structural element, advantageously along a path successively and / or alternately covering the junction portions and the zones of the lower and / or upper wall separating two consecutive junction portions. This deposition is repeated along the same path, until a stack of a predetermined height is obtained, measured in the direction perpendicular to the median longitudinal plane of the structural element.

[0027] In practice, the one-dimensional fibrous element can be made in different ways, in particular in the form of a textile thread, a wick, or even a narrow woven ribbon. Advantageously, the one-dimensional fibrous element is based on a material having a modulus of elasticity greater than 10, or even 50 or 80 GPa, including glass, carbon, basalt, aramids, as well as certain natural fibers such as linen.

[0028] In other words, the reference plane, which will constitute one of the lateral faces of the structural element, receives a deposit of the material integrating the fibrous reinforcement which continuously draws the profile of the junction portions. This deposit connects one junction portion to the other along a segment of an upper or lower wall. In other words, the deposition of the material is done on a trajectory which corresponds to the profile of the structural element along a plane parallel to the median longitudinal plane. This deposition of the fibrous element being continuous, it results in a part which has a mechanical continuity favorable to the mechanical properties of the structural element, both with regard to compression and bending.

[0029] In practice, the manufacturing method can be implemented by placing on the reference plane members delimiting at least in part the shape of the joining portions, to allow the deposition of the one-dimensional fibrous element around its members. In other words, these members define the shape of the joining portions, and allow the fibrous reinforcement to remain in the desired configuration as the deposition progresses, so as to obtain joining portions having a constant section over the entire width of the structural element.

[0030] For example, these reinforcements can be tubes around which the wire is wound, or axes or points perpendicular to the reference plane, and around which the fiber reinforcement forms the angles present in the geometry of the joining portions. These members are removed after the resin impregnating the fiber reinforcement has hardened.

[0031] In a particular embodiment, the deposition of the one-dimensional fibrous element can be carried out on a strip based on a material capable of adhering to the impregnation resin of the one-dimensional fibrous element. In this way, this strip will form one of the side walls of the structural element. In the case where the structural element is an edge, the strip is intended to come into contact with the core, or to form the visible face of the sliding board so as to prevent snow from entering the openings of the structural element.

[0032] In other embodiments, to prevent snow from entering the structural element, an insert may be clipped or glued to the side face of the structural element. The top of the board may also descend onto the structural element. This structural element may also be subsequently filled by injection of foam, partially or completely, during the manufacture of the board.

[0033] The invention more specifically described for a structural element can be applied to other internal structural elements of a sliding board. It can of course be the core of the board, which can adopt the above structure, as regards its geometry and its constitution.

[0034] The manufacturing process described above can be applied to the production of both a core and an edge element. Summary description of the drawings

[0035] The manner of carrying out the invention, as well as the advantages which result therefrom, will emerge clearly from the description of the embodiments which follow, supported by the appended figures in which: There figure 1 is a summary perspective view of a ski equipped with an edge made in accordance with the invention. figure 2 is an enlarged partial view of the figure 1 . There figure 3 is a partial summary perspective view of the singing element of the figure 1 , shown in isolation from the sliding board. The figures 4, 5 and 6 are cross-sectional views of the sliding board of the figure 1 , according to transverse planes respectively IV-IV', V-V', VI-VI' of the figure 2 . THE figures 7, 8, 9 and 10 are summary perspective views of variants of the edge element of the figure 3 . There figure 11is a schematic perspective view illustrating a method of carrying out the manufacturing process of the edge element of the figure 3 . There figure 12 is a summary perspective view cut away of a sliding board incorporating a core made in accordance with the invention. figures 13, 14 And 15 are cross-sectional views of the sliding board of the figure 12 , on plans XII-XIII', XIV-XIV' and XV-XV' respectively of the figure 12 . Ways of carrying out the invention

[0036] The invention is more particularly described below in a specific application of a structural element suitable for an alpine ski, but it of course covers applications to other types of sliding boards than, for example, snowboards and cross-country skis.

[0037] In the remainder of the description, unless specifically indicated, the structural element will be described as oriented such that its major dimension, parallel to that of the ski, is horizontal and its lower wall is parallel to a horizontal plane, parallel to the base of the ski. In this way, its length corresponds to its dimension measured along the major dimension of the ski, its width is measured along a horizontal direction transverse to the ski and its thickness is measured vertically. In the following examples, the structural element corresponds either to an edge element as in figures 1 to 6 , either to a core as to the figures 12 to 15 .

[0038] There figure 1 illustrates an alpine ski 1 having an upper face 2 a sole 3 and whose side faces 4 are equipped with a singing element 10 in accordance with the invention. This singing element 10extends laterally over all or part of the length of the ski, between the heel 5 and the spatula 6. In the illustrated case, this edge element has internal and external lateral faces perpendicular to the plane of the ski sole. In other embodiments not shown, these lateral faces and in particular the external face, could be inclined relative to the plane of the ski sole.

[0039] As illustrated in the figure 2 , the singing element 10 characteristic extends into an area where the thickness of the ski is sufficient, and is extended by a complementary monolithic element 9. More specifically, this element of singing 10 has a lower wall 12 is an upper wall 11 which are parallel to the sole respectively 3 and to the upper layer 2 skiing. These two upper walls 11 and lower 12are connected to each other by junction portions 15, which have a circular shape in the embodiment illustrated in Figures 2 and 3 .

[0040] More precisely, these joining portions have a cylindrical shape, the axis of revolution of the cylinders being perpendicular to the median longitudinal plane 13, which is perpendicular to the lower wall 12, and which extends along the length of the edge element. This median longitudinal plane 13 is, in the case of a ski, parallel to the median longitudinal plane of the ski itself. This plane is therefore substantially perpendicular to the plane of the sole of the ski parallel to the external lateral face of the ski and therefore of the edge element, as well as to the surface of the edge element opposite the core 8, as illustrated figure 4 .

[0041] As illustrated in the figure 6 , these junction portions 15are separated from each other by through openings 16, extending from one lateral face to the other of the edge element, for example and preferably perpendicular to the median longitudinal plane 13. In this way, the joining portions 15 are not joined, but on the contrary spaced from each other. Thus, as illustrated in the figure 6 , at the level of plan VI-VI' of the figure 2 , the singing element is formed of only the lower walls 12 and higher 11, at the level of the through opening 16. Conversely, and as illustrated in the figure 4 , at the level of plan IV-IV' of the figure 2 , corresponding to a cutting plane at the level of the maximum height of the junction portion 15, the upper wall of the edge element 11 is in contact with the upper region 17 of the joining portion. In the same way, the lower wall 12of the singing element is tangent to the bass region 18 of the junction portion 15. At the intermediate level illustrated in the Figure 5 , at the level of the VV' plan of the figure 2 , the junction portion is located at intermediate heights between the upper walls 11 and lower 12.

[0042] Remarkably, the section of each of the junction portions, circular in the case of the figures 2 to 6 is constant regardless of the cutting plane parallel to the median longitudinal plane 13. In other words, each junction portion has a continuous section across its entire width.

[0043] This particular geometry applicable to a structural element to form either an edge element or a core, results in particular from the preferred manufacturing method illustrated in figure 11 .

[0044] The characteristic structural element is produced by additive manufacturing, or 3D printing. In the case of additive manufacturing, the material deposition can be done layer by layer, the layers being stacked on top of each other either in the direction of the width of the edge element, or in the direction of the thickness of the edge element. In the preferred mode of the figure 11 , the material deposition is carried out layer by layer, the layers being stacked in the width direction by the deposition of a continuous wire from the first layer to the last layer. The edge element is manufactured from a sheet 30 forming a support, on which organs have been placed 31 delimiting the interior shape of the future junction portions.

[0045] This sheet 30 then receives the deposit of a resin-impregnated wire or ribbon type material delivered by a nozzle (not shown), which is deposited along a path32 which follows the location of the future upper wall 41, passing tangentially around the organs 31. Around each organ 31, the nozzle moves in a circular path, forming a spiral 35, intended to form the future junction portion 45. In the illustrated form, the turns are circular, but they could adopt different shapes, triangular, or more generally polygonal, or even irregular shapes, as long as they are shapes with a closed contour in which the wire passes back on itself. The trajectory of the deposit 32 continues successively following the outline of each of the organs 31, so as to form all the junction portions. In the illustrated form, this trajectory draws rectilinear fractions between each organ 31, in order to constitute the future upper wall 41.At the level of the last cylindrical organ 36, the trajectory of the deposit 32 goes back in the opposite direction, to create in a similar way the rectilinear segments which will form the future lower wall 42 of the singing element. Advantageously, in this second part of the trajectory, the nozzle can also travel in circles around the organs 31, so as to form additional turns of the future joining portions. The process is continued iteratively, so that the nozzle trajectories overlap, and form turns which stack up both at the upper walls 41 and lower 42 only junction portions 45. The number of iterations required is determined to obtain a sufficient deposit height, corresponding to the future width of the edge element.

[0046] Note that the sheet 30is arranged horizontally, at the start of manufacturing, so that the turns stack vertically. However, the vertical direction of this stacking corresponds to a horizontal and transverse direction of the edge element once finished and positioned in the ski. At the end of this manufacturing, the sheet 30 can be retained to form the wall in contact with the core, or the wall in contact with the external environment in the edge element. This sheet can also be eliminated in certain cases.

[0047] It should be noted that the continuity of the deposit 32, in particular because the deposit incorporates a continuous mechanical element in the form of a wire or a ribbon, gives the finished edge element very high mechanical integrity and high properties in terms of resistance to bending and torsion. Generally speaking, the crushing resistance of the edge element is conferred by the shape of the joining portion45, the number of joining portions as well as the intrinsic mechanical properties of the deposited material, and in particular of its core formed of at least one thread or textile ribbon based on a high tenacity material such as glass, carbon or formed from a natural fiber material such as linen, hemp or basalt.

[0048] Obviously, the trajectory described above can be modified in different ways, for example by linking the upper wall segments of the edge element after each joining portion, or by alternating between each joining portion a segment of the upper wall and a segment of the lower wall, or by first forming one of the lower or upper walls, then the joining portions and finally the other of the upper or lower walls.

[0049] The manufacture of such an edge element is carried out by a 3D printing machine. Such a printing machine comprises a nozzle which delivers a wire or a ribbon impregnated with a resin which hardens after being applied to a support surface. In a first embodiment, the machine comprises a tank containing a bath of thermosetting resin or a mixture of thermosetting and thermoplastic resins in which a fiber wire passes before exiting through the nozzle to be deposited on the support surface. The coated fiber which flows from the nozzle is then heated for example by UV light to be hardened by crosslinking phenomena. In a second embodiment, the wire coated with a thermoplastic material is used, which is heated inside the 3D printing machine to be softened and then applied to the support surface by flowing through the nozzle. The thermoplastic material hardens upon cooling.In the case of resins based on thermoplastic materials, it is necessary that these materials have a sufficiently high softening temperature so that when the ski is molded, the edge retains its shape and does not soften.

[0050] Many variations are of course possible, as illustrated in figures 7 to 10 These variations can apply to both a singing element and a core.

[0051] Thus, as illustrated by the figure 7 , the joining portions 115 are cylindrical, but joined from one portion to the other. Such a structure has greater resistance to crushing, due to the contact existing between two adjacent joining portions. It will also be noted at the figure 7 , the fact that the joining portions have diameters which differ along the length of the edge element, and which adapt to the distance separating the curved upper walls 111and lower plane 112.

[0052] In the variant illustrated in the figure 8 , the joining portions are triangular in shape, and more precisely comprise plane segments 216 217, whose upper ends come into contact with each other to form the summit 218 of the triangle. Complementarily, the lower portions of the segments 216 217 are also in contact from one triangular pattern to the other, such that two consecutive triangles are in contact with each other at the lower end 219 of the same segments.

[0053] In a variant not shown, these triangular patterns may be spaced apart from each other, and not come into contact with each other, by being spaced apart at a low peak or a high peak. Thus, two low peaks will be connected by the lower wall while two high peaks will be connected by the upper wall.

[0054] In a variant illustrated in the figure 9 , the joining portions have trapezoidal shapes. These joining portions 315 are therefore composed of inclined walls 316 317, at opposite angles, individually ensuring the junction between the upper wall 311 and the lower wall 312. These trapezoidal portions are illustrated with a gap 320 between two adjacent joining portions. Obviously, in an alternative embodiment, the trapezoids can be joined, in this case forming a triangular V-shaped pattern.

[0055] In the form illustrated in the figure 10 , the geometry of the figure 9 has been adapted to take into account the variation in thickness of the edge element, corresponding to the variable distance between the upper walls 411 and lower 412 in order to adapt to the evolving thickness curve of the sliding board.

[0056] Obviously, the invention also covers the variants not shown in which the different geometries of the patterns mentioned above are mixed within the same edge element over the length of the edge element, by playing on the shape, the density and the proximity of the joining portions according to the desired mechanical properties, in particular according to the distribution of the stresses during use of the board. Furthermore, this edge element can extend over the entire length of the edge or over only a portion of the edge of the ski.

[0057] Although described in detail above for the production of an edge element, the invention also covers the production of other portions of the structure of a board, and in particular the central core, as illustrated in figure 12 .

[0058] More specifically, this board features a core 510, resting on the lower assembly 503,covered with the top layer 502, and laterally bordered by the edge elements 504 505. The core 510 similarly comprises an upper wall 511 and a lower wall 512, separated by joining portions 515 made in a manner analogous to similar regions of the singing element described above. As illustrated in the figure 12 , these junction portions 515 take a cylindrical shape, the axis of revolution of the cylinders being perpendicular to the median longitudinal plane 513, which is perpendicular to the lower wall 512, and which extends along the length of the core. These junction portions 515 are separated from each other by through openings 516, extending from one lateral face to the other of the core, for example and preferably perpendicular to the median longitudinal plane 513. In this way, the joining portions 515are not joined, but on the contrary spaced from each other.

[0059] Furthermore, as illustrated in the figure 13 , the core 510 present at the level of the greatest thickness of the junction portions 515, its upper wall 511 and its lower wall 512 which tangent the upper and lower regions of the junction portions 515. As illustrated in the figure 14 , at an intermediate level, the junction portions 515 are found at an intermediate height between the upper walls 511 and lower 512 of the element forming the core. And between two junction portions, as illustrated in the figure 15 , the core simply comprises its upper wall 511, in contact with the upper assembly 502, and its lower wall 512, coming into contact with the lower assembly 503.

[0060] Of course, all the variations of material shape geometries described for the edge element above can be applied to the production of the core.

[0061] Furthermore, the edge element or the core can be used in manufacturing processes known for the manufacture of sliding boards. In particular, in the case of skis, the edge element and / or the core can be used in a traditional molding including fibrous composite materials associated with an impregnation resin, which forms the resin for bonding the different elements of the ski together. In this case, the edge element and / or the core can remain hollow, or be partially filled with resin.

[0062] The invention can also be used in the case of foam injection molding, for example polyurethane, which allows all the elements of the ski to be bonded together. In this case, the edge element and / or the core will be partially or completely filled with the injection foam.

[0063] It is clear from the above that the board structural elements according to the invention, in particular the edge elements or the core, have great lightness, sufficient rigidity, with the possibility of adapting to a variation in thickness of the board, of adapting to the need for crushing resistance and also of adapting to bending and / or torsion which vary along the length of the board.

Claims

1. A method of manufacturing a structural element (10, 510) of a gliding board, said element comprising: - a continuous lower wall (12, 512) and an upper wall (11, 511) having a median longitudinal plane (13, 513) perpendicular to said lower wall (12, 5 12), - a set of junction portions (15, 515) distributed over the length of the structural element (10, 510), each junction portion (15, 515) engaging with the lower (12, 512) and upper (11, 511) walls, said junction portions (15, 515) being separated by openings (16, 516) extending along the width of the structural element (10, 510), wherein the junction portions (15, 515) and the lower (12, 512) and upper (11, 511) walls are produced by additive manufacturing, that is to say by layer-by-layer deposition of material, the layers being stacked on top of each other either in the width direction of the structural element (10, 510) or in the thickness direction of the structural element (10, 510).

2. The method according to claim 1, characterised in that it comprises a step of depositing a continuous one-dimensional fibrous element forming successive superimposed layers in a direction perpendicular to the median longitudinal plane (13, 513).

3. The method according to claim 2, wherein: - a one-dimensional fibrous element, impregnated with a curable resin, is deposited on a reference plane parallel to the median longitudinal plane (13, 513) of an edge element, along a path successively and / or alternately covering the junction portions (15, 515) and the regions of the lower (12, 512) and / or upper (11, 511) wall separating two consecutive junction portions (15, 515), - the deposition is repeated on said path until a stack of a predetermined height measured along a direction perpendicular to the median longitudinal plane (13, 5133) is obtained.

4. The method according to claim 3, characterised in that members (31) at least partially delimiting the shape of the junction portions (15, 515) are placed on the reference plane, to allow said one-dimensional fibrous element to be deposited around said members (31).

5. The method according to claim 2, characterised in that said one-dimensional fibrous element is a textile yarn or a woven tape.

6. A gliding board structural element obtained according to the method of any one of claims 1 to 5.

7. The structural element according to claim 6, characterised in that each junction portion (15, 515) has a consistent cross-sectional shape by moving in a direction perpendicular to the median longitudinal plane (13, 513).

8. The structural element according to claim 6, characterised in that all or part of the junction portions (15, 515) has a hollow section.

9. The structural element according to claim 6, characterized in that at least two adjacent junction portions (115) engage with each other.

10. The structural element according to claim 6, characterised in that at least two consecutive junction portions (15, 515) are spaced apart from each other.

11. The structural element according to claim 6, characterised in that at least one junction portion (215) has a polygonal shape.

12. The structural element according to claim 6, characterised in that at least one junction portion (15, 515) has a shape including a curved region, in particular a circular shape.

13. The structural element according to claim 6, characterised in that at least two junction portions have different shapes and / or sizes (415).

14. The structural element according to claim 6, characterised in that it also comprises at least one side wall substantially parallel to the median longitudinal plane.

15. The structural element according to claim 6, characterised in that the lower (12, 512) and upper (11, 511) walls are parallel.

16. The structural element according to claim 6, characterised in that the distance separating the lower (112) and upper (111) walls is variable along the length of said element.

17. The structural element according to claim 6, characterised in that it comprises a continuous one-dimensional fibrous element (32) which forms the junction portions, and the lower and upper walls.

18. The structural element according to claim 17, characterised in that the one-dimensional fibrous element is wound along a path successively and / or alternately through the junction portions and the region of the lower and / or upper wall separating two consecutive junction portions.

19. The structural element according to claim 17, characterised in that the one-dimensional fibrous element is wound in turns and / or segments parallel to the median longitudinal plane.

20. The structural element according to claim 6, characterised in that the structural element is a core or an edge element.

21. A gliding board incorporating at least one structural element according to any one of claims 6 to 20.

22. The gliding board according to claim 21, characterised in that the structural element is covered by a closing wall.