EP3037141B1 - Snowboard with complex sidewalls - Google Patents

Description

Technical area

The invention relates to the field of snow sliding sports, and more specifically that of alpine skiing or snowboarding, snowboard simultaneously receiving both feet of the user. It relates more particularly to a new gliding board structure, as regards the constitution of side edges. It aims in particular to confer a particular behavior with regard to the transmission of forces on the edge, when tilting the inclination of the board during the turning phases.

Background of the invention

In general, an alpine ski has a structure that includes a lower assembly, formed of the edge edged edge, generally associated with one or more mechanical reinforcement layers. The ski also comprises an upper assembly, which also includes at least one mechanical reinforcing layer, and which is separated from the lower assembly by a core which allows to move the lower and upper reinforcing layers of the neutral fiber.

In sandwich-type structures, the ski also has lateral elements forming the edges, whose role is to protect the core from external aggression, and to allow the transmission of the supports from the upper face, and in particular from the reinforcements. to the edges.

It has already been proposed to make the songs from several elements assembled parallel in the vertical direction. So, the Applicant described in the document EP 0 180 678 a ski whose edges are made by assembling several layers of materials of different types, some of which appear on the upper face, thus protecting the upper edges of the upper face. The publication EP 0850785 A1 also discloses a gliding board on snow with songs consisting of at least three elements, the songs being constituted by the extension downwardly laterally on the core of the upper assembly.

Moreover, it was described in the document AT 388 875 , a particular song, which has on its inner face a layer of a polymeric material, and in particular elastomeric in contact with the core of the ski. This structure makes it possible to give mechanical mobility to the song with respect to the nucleus. It has the disadvantage of reducing the intensity of the forces transmitted to the edge, and degrade the behavior of the ski.

Presentation of the invention

• un ensemble inférieur comprenant une semelle bordée de carres et au moins un renfort inférieur,
• un ensemble supérieur incluant au moins un renfort supérieur,
• un noyau séparant ces ensembles inférieurs et supérieurs,
• des chants rapportés sur les côtés latéraux du noyau et recouverts par l'ensemble supérieur, ces chants étant interposés verticalement entre l'ensemble supérieur et l'ensemble inférieur, ces chants étant constitués de plusieurs éléments solidarisés entre eux et positionnés sensiblement verticalement.

One of the objectives of the invention and to improve the behavior of the gliding board in turns or more generally when the board is inclined, in particular to optimize the transmission of efforts at the edges.
To do this, it is proposed a snow sliding board having an internal structure comprising:

• a lower assembly comprising a sole edged with edges and at least one lower reinforcement,
• an upper assembly including at least one upper reinforcement,
• a core separating these lower and higher sets,
• edges added to the lateral sides of the core and covered by the upper assembly, these edges being interposed vertically between the upper and lower assemblies, these edges consisting of several elements joined together and positioned substantially vertically.

According to the invention, this board is characterized in that at least one of the edges consists of three elements, namely an internal element, an intermediate element, and an external element. More specifically, the intermediate element consists of an elastomeric material, the inner element has a compressive stiffness greater than the compression stiffness of the outer element.

In other words, the invention consists in using songs that are composed by the assembly of three distinct elements, each having a specific role in the transmission of supports to the edge. Thus, the inner element of the song, which has the highest rigidity in compression makes it possible to ensure the transmission supports from the upper layer and in particular from the upper reinforcement, to the edges, and more precisely to the level of the fins and edges.

Complementarily, the intermediate element, elastomeric base acts as a buffer due to the fact that the outer member has a lower compression stiffness, allowing the faster deformation of the outer member relative to the inner member some singing. The vertical shear induced within the elastomeric intermediate member dissipates energy to create the damping effect, and thereby generate a suspension type connection between the upper reinforcement and the edge.

In practice, this suspension effect is all the more marked as the difference between the compression stiffnesses of the inner and outer elements is important. It is recalled that the compression stiffness is calculated as the product of the Young's modulus by the average thickness of the element concerned. Thus, it is considered that the Young's modulus in compression of the internal element of the edge may advantageously be greater than 15 GPa, preferably greater than 30 GPa, while the Young's modulus of the external element must be smaller than 11 GPA, preferably less than 2 GPa.

Good results are thus obtained by using, as internal element, a metallic material, typically based on aluminum, and for the external element a polymeric material, for example of the acrylo-butadiene-styrene (ABS) type. On the other hand, the intermediate element, of elastomer type, has a particularly low Young's modulus, as well as a Shore hardness of less than 80 Shore A, and preferably of between 60 and 80 Shore A. It can for example be act of rubber-like materials, natural or synthetic, or of thermoplastic elastomers of the SEBS type.

In practice, different variants can be envisaged with regard to the geometry and positioning of the characteristic edges. Thus, the layer of Elastomeric material forming the inner member may extend vertically over the entire height of the edge, between the upper reinforcement and the lower reinforcement. Similarly, this elastomeric intermediate element may be present on all or part of the total length of the edge, and in particular be present on the fraction of the edge extending in the zone of the pad to the spatula, corresponding to the zone in which the most important efforts are transmitted on the edge, and where the attachment of the ski on the snow is essential.

In practice, it may be advantageous for the internal element of the edge to ensure direct transmission of the forces between the upper reinforcement and the lower reinforcement. In this case, the base of the inner element is located above the edge of the edge while the upper part of this inner element of the edge is in contact with the layer or layers of upper reinforcements.

To increase the compression stiffness gap between the inner and outer elements of the edge, it can be expected that the external element of the song has recessed shapes, with recesses material. For aesthetic reasons, this external element can be made of a transparent material.

In practice, it is also possible to design the outer element of the song by making it into several elements juxtaposed along the length of the ski, so as to adjust the compression stiffness of each of the portions.

Still for aesthetic purposes, the outer element of the edge can incorporate a decorative layer, advantageously protected from the outside, especially if this element is transparent and the decorative pattern has been made on its inner face.

For this purpose of suspension can be added a damping effect of the flexural structure in certain configurations. Thus, it can be expected that the board has an elastomeric layer interposed between the core and the assembly higher and / or lower. In this case, this elastomeric layer forms with the intermediate elements of the songs a kind of partial or total envelope of the core.

In an alternative embodiment, the board may comprise an elastomeric layer interposed between the core and the upper and / or lower face of the lateral element of the outer edge. In other words, there is provided an elastomeric layer which laterally extends the elastomeric layer formed by the intermediate element of the edge.

Brief description of the figures

The manner of carrying out the invention, as well as the advantages derived therefrom, will emerge clearly from the description of the embodiments which follow, in support of the appended figures in which the Figures 1 to 6 are cross-section views of ski according to six embodiments.

detailed description

The figure 1 illustrates a ski structure according to the invention, in which many elements are common to the different embodiments of the other figures, and will therefore only be described in detail only once.

Thus, this ski 1, of "sandwich" structure, comprises a lower assembly 2 including a sliding week 6, bordered by edges 3. The cords 4 of the edges 3 are located in the lateral extension of the sole 6, and are extended by fins 5, which rests on the sole 6, inside the structure to increase the mechanical anchoring of the edge. The lower assembly 2 also comprises a first reinforcement 7 disposed above the soleplate, and which extends laterally to the fins 5 of the edges 3. The upper assembly also comprises a second reinforcing layer 8, which is extends to the side faces of the board. The ski also comprises an upper assembly 10 which includes an upper protective and decorative layer 11, resting on three layers of mechanical reinforcements 12, 13, 14. The upper assembly 10 is separated from the lower assembly by means of the core 9. This core may be made of a relatively light material, such as wood or polyurethane foam, for the purpose of spreading the upper and lower assemblies, and in particular the reinforcing layers with respect to the neutral fiber, for to obtain the flexural rigidity necessary for skiing. In known manner, the thickness of the core is variable along the length of the ski.

Laterally, the core is bordered by edges 20, laterally separating the core 9 from the outside, and interposed vertically between the upper assembly 10 and the lower assembly 2.

According to the invention, this edge 20 is composed of three distinct elements. A first element 21 or external element forms the visible lateral face of the ski. The inner member 23 has its inner face in contact with the core 9 and has its base 25 in contact with the lower assembly 2, and its upper end 24 in contact with the upper assembly 10. Between the outer member 21 and the internal member 23 is the intermediate member 22 typically made of an elastomeric material and in particular rubber.

As already mentioned, the internal 23 and outer 21 elements of the edge have distinct mechanical properties, in that the inner member 23 has a compression stiffness significantly greater than that of the outer member 21. More specifically, in a particular embodiment, the inner element can be made by an aluminum plate, whose Young's modulus is 70 GPa, a thickness of the order of a millimeter or less, giving a compressive rigidity greater than 70000 N / mm. The inner member 23 may also be made based on a superposition of papers impregnated with a phenolic resin, whose Young's modulus is close to 18 GPa. In the latter case, the thickness of the inner element is of the order of several millimeters, typically between 3 and 5 mm, inducing a compressive rigidity of the order of 50000 to 90000 N / mm. Other materials, adapted in thickness, can be chosen respecting the resistance value in high compression, between 50000 and 90000 N / mm.

Complementarily, the outer element of the edge has a significantly lower compression stiffness. This external element 21 may be made for example based on a superposition of papers impregnated with a melamine resin, which has a Young's mode of the order of 10 GPa, with a thickness of the order of 1 to 3 mm. The compressive rigidity is between 10,000 and 30000 N / mm. It may also be an acrylo-butadiene-styrene ABS material, whose Young's modulus is close to 2 GPa, which has a thickness of several millimeters, of the order of 2 to 5 mm, giving a rigidity of the order of 4000 and 10000 N / mm. The thickness is chosen as a function of the geometry of the board, in particular the existence or not of inclined faces at the level of the edges, and the desired value of compressive rigidity. Of course, other materials adapted in thickness can be chosen with a compressive strength of between 4000 and 30000 N / mm.

The intermediate element 22 is for its part made typically based on rubber, and has a thickness of a few tenths of millimeters and a few millimeters, typically close to 0.5 mm. The three elements are glued together before or during molding.

The external element of lower compression stiffness is thus coupled to the rubber intermediate element forming the damper. The external and intermediate element are respectively equivalent to a stiffness and a shock absorber connected in parallel. The damper only plays its role when the stiffness is low. All of these two elements form the suspension of the edge relative to the rest of the structure.

In the form illustrated in Figures 2 to 6 , side edges are not beveled, to facilitate compaction stiffness calculations. In the case of figure 2 , and the outer member 31 of the edge 30 has a planar and vertical outer face. This external element 30 is in comparison thicker than that of the figure 1 However, in practice the outer element is most often beveled, and the calculation of the stiffness is done with the average thickness. In the same vein, the inner element 33 of the edge 30, based on a superposition of papers impregnated with a phenolic resin is thicker on the figure 2 that the analogous metal element of the figure 1 .

The configuration illustrated in figure 3 comprises two additional layers 45, 46 of an elastomeric material, typically based on rubber, of a very fine thickness, of a few tenths of a millimeter, typically of 0.18 mm. In this embodiment, the layers 45 and 46 respectively extend above the core over the entire width thereof, and interrupt with it without passing either above or below the inner member 43. of singing 40.

In the variant illustrated in figure 4 , the elastomeric layers 55, 56 interposed between the core and the upper assembly 10 and the lower assembly 2 extend laterally to above and below the inner element 53 of the edge 50.

In the variant illustrated in figure 5 , the board comprises an elastomeric layer, interposed between the core 9 and the upper assembly 10. More specifically, this layer 65 extends laterally to come into contact with the intermediate element 62 of the edge 60. Complementarily, the board comprises two rubber strips 66, 76, interposed between the underside of the external element of the edge 60 and the lower assembly 2. These strips 66, 67 come into contact with the intermediate element 62 of the edge 60.

A similar structure is illustrated in figure 6 . This structure comprises a typically elastomeric layer 75, interposed between the core 9 and the lower assembly 2. This elastomeric layer extends laterally to the level of the intermediate elements 72 of the edge 70, also elastomeric. Unlike the figure 5 the board also comprises two elastomeric strips 76, 77 disposed on the upper face of the outer member 71 of the edges 70.

Of course, each of the internal or external elements can be achieved by the assembly of vertical elementary layers, respecting the ratios between the compressive stiffnesses of the two global elements, calculated as the sum of the stiffnesses of each elementary layer.

The elastomeric material of the intermediate member may exhibit viscoelastic properties in the temperature range of -20 ° C and 10 ° C to improve the damping phenomenon.

Although described in detail for a ski structure, the invention also applies to snowboarding.

It follows from the above that the gliding board according to the invention has multiple advantages, in particular that of ensuring both a good transmission of efforts from the top of the board to the edge, by the intermediate of the inner member of the singularly rigid, while adding a suspension formed by all of the outer member and the intermediate member. Therefore, it is easier for the user to control his trajectory, to increase the resistance of the board on the curve, the latter being more stable, because the suspension partly filters the vibrations induced by the geometry of the terrain. . The gliding board is thus more efficient for evolution in competition, because it thus provides a feeling of comfort in the turning phases.

Claims (15)

1. Snowboard (1) with an internal structure incorporating:

   - one bottom assembly (2) with a sole (6) that is edged with ski edges (3) and at least one bottom reinforcement (8);

   - one top assembly (10) incorporating at least one top reinforcement (14);

   - one core (9) separating the aforesaid bottom (2) and top (10) assemblies;

   - rims (20) added onto the sides of the core and covered by the top assembly, with these rims being positioned vertically between the top assembly (10) and the bottom assembly (2), and with these rims being composed of multiple parts integral with each other and positioned essentially vertically;

   characterized by the fact that at least one of the rims is composed of three parts, namely one interior part (23), one intermediate part (22) and one exterior part (21), in which the intermediate part (22) is composed of an elastomeric material and the interior part (23) has a compression rigidity exceeding the compression rigidity of the exterior part (21).
2. Snowboard in accordance with claim 1, characterized by the fact that the compression rigidity of the interior part is between 50,000 and 90,000 N/mm, and the compression rigidity of the exterior part is between 4,000 and 30,000 N/mm.
3. Snowboard in accordance with claim 1, characterized by the fact that the Young's modulus under compression of the interior part (23) of the rim is greater than 15,000 MPa, and preferably greater than 30,000 MPa.
4. Snowboard in accordance with claim 1, characterized by the fact that the Young's modulus under compression of the exterior part (21) is less than 11,000 MPa, and preferably less than 2,000 MPa.
5. Snowboard in accordance with claim 1, characterized by the fact that the interior part (23) is composed of an aluminum layer, and by the fact that the exterior part (21) is composed of a polymeric material.
6. Snowboard in accordance with claim 1, characterized by the fact that the interior part and the exterior part are formed by the assembly of multiple layers.
7. Snowboard in accordance with claim 1, characterized by the fact that the intermediate layer has a hardness of between 60 and 80 Shore A.
8. Snowboard in accordance with claim 1, characterized by the fact that the intermediate part (22) is composed of a layer made of a material chosen from the group including rubber and thermoplastic elastomers of SEBS type.
9. Snowboard in accordance with claim 1, characterized by the fact that the intermediate part (22) extends over the entire height of the rim.
10. Snowboard in accordance with claim 1, characterized by the fact that the intermediate part (22) is present on the entire length of the rim.
11. Snowboard in accordance with claim 1, characterized by the fact that the layer of elastomeric material is present on the portion of the rim extending from the area of the pad up to the cheek.
12. Snowboard in accordance with claim 1, characterized by the fact that the top part (24) of the interior part is in contact with at least one layer of upper reinforcement (14).
13. Snowboard in accordance with claim 1, characterized by the fact that the exterior part of the rim has hollow imprints.
14. Snowboard in accordance with claim 1, characterized by the fact that the exterior part of the rim is composed of a transparent material.
15. Snowboard in accordance with claim 1, characterized by the fact that it incorporates an elastomeric layer (45, 46, 55, 56, 65, 75) positioned between the core (9) and the top assembly (10) and/or bottom assembly (2).

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