EP1421978A1 - Gliding board and it's method of manufacturing - Google Patents

Abstract

The ski or snowboard has an injected plastic foam core, side reinforcing elements (13, 14) and a transverse inner reinforcing member, with outer layers (11, 23) forming a sole and upper protective surface. The edges of the inner reinforcing member rest in recesses (16) in the side reinforcing elements and have notches (3) between 15 and 60 mm long and a few millimetres wide for the passage of injected core foam between the lower and upper cavities (20, 21). In a variant of the design the side reinforcing element recesses can be in the form of grooves.

Description

Technical area

The invention relates to the field of snow sliding sports. She aims more particularly a new board structure, that is to say alpine or derivative skiing, such as Nordic skiing, as well as snowboarding. She aims more particularly a new board structure, and a method of associated manufacturing, which make it possible to produce boards with injected core whose upper side has marked relief effects, the internal structure of which has rigid reinforcements.

Previous techniques

Generally, gliding boards have a core which is made either as a pre-element, or from injection and molding operations during which chemical components are introduced into a mold, and react so as to expand to form the nucleus in situ. Specifically, this expansion takes place in the volume defined between two upper outer layers and lower respectively forming the upper protective layer of the board and the gliding sole, as well as lateral reinforcing elements, forming all or part of the songs. During injection, and the subsequent expansion, these different elements are pressed against the die and the mold cover.

In general, the mechanical properties of the injected skis are directly related to the use of internal reinforcements which generally have strong rigidity. This type of reinforcement is generally made either of metal or based on fibrous materials, and in particular by laminates which may be based glass fibers. The choice of materials, as well as the dimensions of the reinforcement and its positioning within the nucleus, are preponderant to obtain the desired mechanical characteristics.

Also because the nucleus expands, it pushes outward all elements contained in the volume it fills. All reinforcements substantially planes known to date are generally arranged either in contact with the layer forming the sole or the upper protective layer, possibly with the interposition of other specific reinforcements. To ensure proper positioning of the reinforcement during the injection operation, the latter is generally glued previously on the outer layer in contact with which it comes, which avoids the displacement of this reinforcement during the movement of the foam polyurethane.

A problem arises with gliding boards whose upper face is not not strictly flat, but on the contrary has recesses and the like bosses. Indeed, in this case, it is not possible for the rigid reinforcement to deform to conform to the external shape of the board. A solution to this problem was proposed by the Applicant in document FR 2 818 915. This solution consists in making openings within the rigid reinforcement to allow the upper protective layer to deform according to the desired volume, without excessively deforming the reinforcement itself. These openings can be complete, thus promoting the passage of polyurethane foam. These openings can also be partial so as to allow the local deformation of the reinforcement which remains stuck under the upper layer of protection.

However, these solutions have some drawbacks, since it is difficult to precisely limit the passage of the foam constituting the core. This sealing problem penalizes the precision in the reproducibility of the shapes. On the other hand, these solutions force the reinforcement to be located immediately below of the upper protective layer. However, it can be interesting to position the reinforcement at an intermediate height, and not directly in below the top protective layer or directly above the sole.

Another solution allowing the reinforcement of the layers to be removed proposed by document FR 2 312 273, consists of perforating the reinforcement rigid over its entire surface in order to let the foam pass on both sides. This solution has the disadvantage that the realization of openings in the reinforcement inevitably produces an at least local decrease in the stiffness of the reinforcement. Thus, in the case of fibrous reinforcements, the cuts made in the reinforcement break the continuity of certain fibers, and therefore decrease the overall resistance reinforcement.

A problem which the invention proposes to solve is that of being able use reinforcements whose height is optimized to give stiffness specific to the board. Another problem is that of keeping the reinforcement intrinsic properties so as to influence the stiffness of the plank of the desired way.

Statement of the invention

• un noyau injecté en mousse de polyuréthanne,
• des éléments de renforcement latéraux formant tout ou partie des chants de la planche ;
• au moins un renfort interne se présentant en forme d'une couche pleine ;
• deux couches extérieures, à savoir une couche inférieure formant la semelle et une couche supérieure formant la couche de protection de la planche.

The invention therefore relates to a gliding board which comprises, in a known manner:

• a core injected with polyurethane foam,
• lateral reinforcing elements forming all or part of the edges of the board;
• at least one internal reinforcement in the form of a solid layer;
• two outer layers, namely a lower layer forming the sole and an upper layer forming the protective layer of the board.

According to the invention, this board is characterized in that the internal reinforcement rests on recesses provided for this purpose in each of the lateral reinforcement elements. This internal reinforcement also has notches on its lateral edges, so that it is crossed at the notches by the injected core, which thus at least partially fills the volume defined between the internal reinforcement and at least one of the external layers.

In other words, the characteristic reinforcement extends over the entire width of the board, with the exception of the indented areas which connect the volumes located above and below the reinforcement, to allow circulation of the foam expanding during the formation of the core.

It is therefore possible to arrange the reinforcement at a precise height and calculated according to the mechanical characteristics desired by the board.

In addition, by allowing the polyurethane foam to spread in particular above the reinforcement by crossing it by its selvedges, it is possible to give the upper form of the board a non-planar configuration, with a great freedom in the different volumes, bosses and other recesses that we wish to achieve. The characteristic reinforcement is not deformed by the presence of these different additional volumes, and therefore retains all of its mechanical characteristics.

Thus, it is possible to arrange the reinforcement either in the upper part or in lower part of the nucleus. So when the injection point is below the reinforcement, this foam spreads over the reinforcement, and fills the volume located below the upper protective layer. Conversely, when the injection point is located above the reinforcement, the polyurethane foam spreads and expands passing under the reinforcement, and coming into contact with the sole.

Advantageously in practice, the notches made in the reinforcement can be offset longitudinally from one edge to the other of the reinforcement, so that it retains a minimum width sufficient to maintain rigidity desired. Thus over its entire length, the reinforcement is maintained either on one side or the other, which prevents its deformation upwards or downwards.

In practice, the internal reinforcement can cooperate with the elements of lateral reinforcement at different levels.

Thus, the reinforcement can rest on a recess forming a shoulder made either in the upper part or in the lower part of the reinforcing element lateral, or even in a groove-shaped recess made on the face internal side element, at an intermediate level.

In the case where the reinforcement rests in a recess on an upper part side reinforcement element, it can receive over the contact of the protective top layer.

In practice, the internal reinforcement can be of very varied natures, and in particular based on a fibrous laminated material, or even a metallic material.

As already mentioned, the invention also relates to a method of manufacture by injection or molding of a gliding board which comprises so known side reinforcing elements forming all or part of the edges of the board, outer layers forming the sole and the upper layer of protection, as well as at least one internal reinforcement. The method implements a step of in situ injection of chemically reactive components to constitute foam expanding to form the core of the board. The process according to the invention is characterized in that, when the different components of the board in the mold, we block the reinforcement internal in recesses made for this purpose in the reinforcing elements side.

This internal reinforcement has lateral notches highlighting communication the volumes defined above and below the reinforcement so to allow a circulation of the foam expanding during the formation of the core.

Brief description of the figures

La figure 1 est une vue de dessus d'un renfort interne conformément à l'invention.

La figure 2 est une vue en perspective sommaire illustrant la mise en place d'une partie des éléments constitutifs d'un ski dans le moule de fabrication.

La figure 3 est une vue en coupe transversale du ski illustré à la figure 2, juste avant l'opération d'injection.

La figure 4 est une vue en coupe transversale d'un ski réalisé selon une variante d'exécution.

The manner of carrying out the invention as well as the advantages which result therefrom will emerge clearly from the description of the embodiment which follows, in support of the appended figures in which:

Figure 1 is a top view of an internal reinforcement according to the invention.

Figure 2 is a summary perspective view illustrating the establishment of a portion of the components of a ski in the manufacturing mold.

Figure 3 is a cross-sectional view of the ski illustrated in Figure 2, just before the injection operation.

Figure 4 is a cross-sectional view of a ski produced according to an alternative embodiment.

Way of realizing the invention

As already mentioned, the invention is based on the integration within a gliding board of a characteristic reinforcement, having a geometry whose Figure 1 is an example.

Such a reinforcement has a width substantially equal to that of the board, and a length that corresponds to the length in which we want it stretches along the ski.

This reinforcement (1) has multiple notches (2, 3) distributed over each sides of the reinforcement, and separated by rectilinear portions (4, 5). In practice, these notches (2, 3) have a length L of the order of 15 to 60 mm, and a width ℓ of the order of a few millimeters, typically 2 to 6 mm wide.

In the illustrated form, the notches (2, 3) are arranged on either side reinforcement, and offset from each other so that the width reinforcement is only reduced by the width of a single notch.

The reinforcement is put in place as illustrated in Figures 2 and 3. Thus, the various elements are placed in a bottom (10) of the mold constituting the lower assembly of the board, namely the sole (11), as well as the edges (12). Different reinforcements can be placed directly above the sole, without interfering with the present invention.

Thereafter, the reinforcing elements (13, 14) are arranged above edges (12), at the edge of the mold housing (10). In the illustrated form, these reinforcing elements also have fins (15) allowing their locking in position in the mold.

Typically, these reinforcing elements have a recess made at their internal upper corner. This recess (16) forms a shoulder on which the edge (4, 5) of the reinforcement (1) can rest.

The notches (3) of the reinforcement (1) define a passage between the volume (20) located below the reinforcement (1) and the volume (21) located above.

This upper volume is limited by an upper protective layer (23). It is observed that the mold cover (18) has recesses making it possible to define the bosses (26, 27) on the board. During the injection of the different constituents reacting to form polyurethane foam, these spread by propagating in the volume (20) located below the reinforcement (1), and passing through the different notches (2, 3) in the upper volume (21), so as to push the protective layer (23) against the bottom of the cover of the mold. The reinforcement (1) is held in position because it receives the contact of the upper protective layer at the reinforcing elements (13, 14).

According to an alternative embodiment illustrated in Figure 4, the reinforcement (1) is positioned at an intermediate level of the height of the board. To do this, it is placed inside grooves (36) in which the flat portions (4, 5) can be integrated. In this case, when the injection is made either above or below the reinforcement, the passage (37) allows communication between the volumes upper and lower (30, 31), and therefore a homogeneous distribution of the foam polyurethane.

It appears from the above that the boards according to the invention have the advantage of having reinforcements which are positioned so optimized to the height necessary to give the desired rigidity. The presence of these reinforcements, however, allows the passage of polyurethane foam which allows to realize at the upper face of the board volumes and very varied shapes, without degrading the mechanical performance of the reinforcement.

Claims (11)

Snowboard including: a core injected with polyurethane foam; lateral reinforcing elements (13, 14) forming all or part of the edges of the board; at least one internal reinforcement (1) in the form of a solid layer; two outer layers forming the sole (11) for the lower layer and the protective layer (23) for the upper layer. characterized in that the internal reinforcement (1) rests on recesses (16) provided for this purpose in each of the lateral reinforcement elements (13, 14), said internal reinforcement having notches (2, 3) on its lateral edges, so that it is crossed at the level of said notches by the injected core which thus at least partially fills the volume (21) defined between the internal reinforcement (1) and at least one of the two outer layers (23). Gliding board according to claim 1, characterized in that the core at least partially fills the volume defined between the internal reinforcement and the upper protective layer. Gliding board according to claim 1, characterized in that the core at least partially fills the volume defined between the internal reinforcement and the lower layer forming the sole. Gliding board according to claim 1, characterized in that the notches (2, 3) produced in the internal reinforcement (1) are offset longitudinally from one edge to the other of said reinforcement. Gliding board according to claim 1, characterized in that the internal reinforcement rests on a recess forming a shoulder formed in the upper part of the lateral reinforcement element. Gliding board according to claim 1, characterized in that the internal reinforcement is blocked by a recess forming a shoulder formed in the lower part of the reinforcing element. Gliding board according to claim 1, characterized in that the internal reinforcement rests in a groove-shaped recess (3, 6) produced on the internal face of the lateral reinforcing element. Gliding board according to claim 5, characterized in that at the level of the lateral reinforcing elements (13, 14), the upper protective layer (23) rests at least in part on the internal reinforcement. Gliding board according to claim 1, characterized in that the internal reinforcement is based on a fibrous laminated material. Gliding board according to claim 1, characterized in that the internal reinforcement is based on a metallic material. Method of manufacturing by injection / molding a gliding board comprising lateral reinforcing elements forming all or part of the edges of the board of the outer layers and at least one internal reinforcement, said method implementing an injection step in situ of chemically reactive components to form a foam which expands in order to form the core of the board, characterized in that when the various constituent elements of the board are placed in the mold, the internal reinforcement is blocked in recesses made for this purpose in the lateral reinforcing elements, said internal reinforcement having lateral notches connecting the volumes defined above and below said reinforcement, so as to allow a circulation of the foam expanding during the formation of the core.

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