EP0546309A1 - Upper ski surface with variable width - Google Patents

Abstract

Ski having the shape of an elongate beam (2) comprising a lower gliding face (3) limited laterally by two lower edges (4, 5), an upper face (6) limited laterally by two upper edges (7, 8) and two lateral faces (9, 10), and consisting of a central part (17) extended at the front (AV) by a front part (18) ending at its front extremity (13) in the tip (14) and extended to the rear (AR) by a rear part (20) ending at its rear extremity (15) in the heel (16), characterised in that the said front part (18) consists of a front portion (25) connected to the central part (17) via an intermediate front linking portion (26), whilst the said rear part (20) consists of a rear portion (22) connected to the central part (17) via an intermediate rear linking portion (24), and in that the two upper edges (7c, 8c) of the upper surface (16) are parallel in the central part (17), whilst one of the two front or rear portions (22, 25) is such that, in this zone, on the one hand the lateral faces (9, 10) are inclined in order to converge upwards and, on the other hand, the upper surface (7) is narrower than in the central part and has a constant width (1a, 1c). <IMAGE>

Description

The present invention relates to an alpine ski, a cross-country ski, a monoski or a snow south. It relates more particularly to an improvement in this type of skiing.

The skis used in particular in the practice of alpine skiing consist of an elongated beam ending at the front by a spatula, and at the rear, by a heel. The thickness of the ski is generally greater in the central part and gradually decreases towards the ends so that the ski somehow forms a beam with a particular flexion.

Current skis generally have a composite structure in which different materials are combined so that each of them intervenes optimally, taking into account the distribution of mechanical stresses when using the ski. Thus, the structure generally comprises peripheral protective elements, internal resistance elements to resist the bending and torsional stresses, and a core, as well as sliding and latching elements. These elements are assembled by gluing or by injection, the assembly generally being carried out hot in a mold having the final shape of the ski, with a front part strongly raised in tip, a rear part slightly raised in heel, a central arched part. .

Despite the manufacturers' concern to manufacture good quality skis, they have not, to date found a high performance ski satisfactory in all conditions of use.

We know that the dimensional and structural characteristics of the ski determine the skiability characteristics of the ski, its dimension line making it possible to make the ski evolve when cornering by promoting its holding in a curve, and its thickness line making it possible to obtain the good bending adjustments. The torsion is adjusted using the edge line.

The French Patent _No. 2,522,978 teaches the use of a ski whose lateral faces are inclined steadily or variable, in order to reduce the side friction when performing turns. The inclination is variable in particular to adapt to variations in width of the upper surface of the ski in the direction of a curvilinear narrowing in the surroundings of the central area. In the region of the fasteners proper, the width can, as shown in Figure 1 of this document, be constant in order to create a platform capable of receiving the fasteners. This form of ski is complicated to manufacture, due to the fact that the upper edges are curvilinear over a large part of the length of the ski. This difficulty appears in particular in modern ski structures which use pre-impregnated fibrous reinforcements, the folding at the edges being difficult and the fibers being unable to be arranged regularly at the upper edges. As a result, the edges are mechanically less resistant. In addition, the non-rectilinear edges of the upper face do not constitute simple and effective markers for the decoration of the upper face by means of sublimation, for example. The French Patent _No. 2,598,930 of the Applicant relates to a ski of which the upper platform has a constant width over the entire length of the ski and whose edges have a variable inclination to adapt to width variations of the riding surface or ski dimension line. This type of ski has a certain number of advantages compared to the skis known to date, but is not completely satisfactory for certain types of snow and certain types of skiers whose skiing practice still requires a certain number of improvements.

The present invention relates on the one hand to improvements made to these skis in order to facilitate their manufacture, and on the other hand, makes it possible to obtain the desired skiability, comfort and resistance characteristics.

Thus, the ski according to the invention has the form of an elongated beam comprising a lower sliding face limited laterally by two lower edges, an upper face limited laterally by two upper edges and two lateral faces, is made up of a central part. extended at the front by a front part terminated at its front end by the spatula and extended at the rear by a rear part terminated at its rear end by the heel, said front part consisting of a front portion connected to the part central by an intermediate front connecting portion, while said rear part is constituted by a rear portion connected to the central part by an intermediate rear connecting portion, the two upper edges of the upper surface being parallel in the central part, while one of the two front or rear portions is such that in this area, on the one hand, the fa these sides are inclined to converge upwards, and on the other hand, the upper surface is narrower than in the central part and has a constant width.

The fact that the ski has portions of constant width or whose upper edges are parallel, in particular aims to facilitate the manufacture of the ski and in particular the cutting and the establishment of an additional additional reinforcement, as well as to improve the resistance of the upper edges in these portions. The fact that at least one of the two front or rear portions has an upper surface with a width less than that of the central part allows, while retaining the aforementioned advantages, on the one hand of having a sufficient space, intended for the location of the bindings, on the other hand, of having a ski whose torsion and flexion values are more modular, depending on the position longitudinal considered, compared to those of skis already known.

According to a particular arrangement, the front portion is such that its upper surface is narrower than in the central part and is limited by the two lateral edges which are parallel.

According to another complementary arrangement, the rear portion is such that its upper surface is narrower than in the central part and is limited by the two lateral edges which are parallel.

According to a particular arrangement, the width of the upper surface of the front portion is equal to the width of the upper surface of the rear portion while in another arrangement, the width of the upper surface of the front portion is different from the width of the upper surface of the rear portion.

According to a preferred arrangement, the lateral faces are also inclined in the central part of the ski, to converge upwards symmetrically with respect to the median longitudinal axis of the ski.

According to an advantageous arrangement, the angle of inclination of the lateral faces varies continuously so that said angle of inclination decreases progressively from the center towards the ends.

The invention makes it possible to optimize the torsional stiffness without modifying the thickness of the ski or the dimension line. Indeed, by modifying the width of the top of the ski, it is possible to obtain the desired characteristics of the torsional behavior of the latter.

• Les figures 1 à 10 illustrent un premier mode de réalisation d'un ski selon l'invention.
• La figure 1 est une vue latérale du ski selon l'invention.
• La figure 2 est une vue de dessus du ski de la figure 1.
• Les figures 3, 4, 5, 6, 7, 8 et 9 sont des vues en coupe transversale selon III-III, IV-IV, V-V, VI-VI, VII-VII, VIII-VIII et IX-IX du ski de la figure 2 selon une échelle différente.
• La figure 10 est un diagramme représentant la variation d'inclinaison des faces latérales du ski.
• Les figures 11 et 12 sont des vues similaires à la figure 4 montrant deux variantes de réalisation.
• La figure 13 est une vue similaire à la figure 4 montrant une autre variante de réalisation.
• Les figures 14 et 15 représentent deux exemples, en vue de dessus, d'un ski selon la variante de la figure 13.
• La figure 16 est une vue en coupe de la structure du ski de la figure 14 selon N-N.
• La figure 17 est une vue en coupe de la figure 14 et de la figure 18 selon M-M.
• La figure 18 est une vue de dessus du ski montrant plus particulièrement en trait interrompu, la couche de renfort (42).

Other characteristics and advantages of the invention will emerge from the description which follows with reference to the appended drawings, which are given only by way of nonlimiting examples.

• Figures 1 to 10 illustrate a first embodiment of a ski according to the invention.
• Figure 1 is a side view of the ski according to the invention.
• Figure 2 is a top view of the ski of Figure 1.
• Figures 3, 4, 5, 6, 7, 8 and 9 are cross-sectional views along III-III, IV-IV, VV, VI-VI, VII-VII, VIII-VIII and IX-IX of the ski Figure 2 on a different scale.
• FIG. 10 is a diagram representing the variation in inclination of the lateral faces of the ski.
• Figures 11 and 12 are views similar to Figure 4 showing two alternative embodiments.
• Figure 13 is a view similar to Figure 4 showing another alternative embodiment.
• FIGS. 14 and 15 represent two examples, seen from above, of a ski according to the variant of FIG. 13.
• Figure 16 is a sectional view of the structure of the ski of Figure 14 along NN.
• Figure 17 is a sectional view of Figure 14 and Figure 18 according to MM.
• Figure 18 is a top view of the ski showing more particularly in broken lines, the reinforcing layer (42).

As known per se and as shown in the figures illustrating it, the ski (1) according to the invention has the form of an elongated beam (2) comprising a lower sliding surface (3) limited laterally by two lower edges (4, 5); it comprises inter alia, an upper surface (6) bounded laterally by two upper edges (7, 8), and two lateral faces (9, 10) connecting the lower edges (4, 5) to said upper edges (7, 8). The body of the ski proper extends between a front contact line (11) and a rear contact line (12) to extend forwards by a raised front part (13), forming the tip (14) and backwards, by a shorter and less raised posterior part (15) forming the heel (16).

It can be seen in FIG. 1 that the ski body (170) considered between the two front (11) and rear (12) contact lines is, in a manner known per se, slightly arched in the rest position without load and has its own thickness distribution. Thus, the thickness (e) is maximum in the central zone to decrease, for example gradually towards the front (AV) and towards the rear (AR).

The ski according to the invention comprises a central part (17) extended forwards by a front part (18) extending from the front end (19) of the central part (17) to the front contact line ( 11), and a rear part (20) extending from the rear end (21) of the central part (17) to the rear contact line (12). The central part (17) of the ski corresponds to the central area for mounting the bindings and extends for example over a length (LC) which can be between 400 and 700 millimeters, and for example be 60 centimeters.

According to one of the characteristics of the invention, the upper surface of the ski (6) in the central part (17) has a constant width (lc). Thus the upper surface (6) of the central part (7) is laterally limited by two lateral edges (7c, 8c) rectilinear and parallel, constituted by two segments respectively (AB) and (CD) rectilinear and parallel distant one of the other by a constant distance (lc).

According to an additional characteristic, the rear portion consists of two separate portions (22, 24), a first intermediate portion (24) connecting to the central portion (17), and a rear portion (22), such as in this one here, the surfa this upper of the ski (6) has on the one hand a width (Ir) less than the width (Ic) of the central part, and on the other hand, is limited laterally by two lateral edges (7r) and (8r) s 'extending in a straight line and parallel to each other. Thus, said width (Ir) is constant over the second rear portion (22) of the rear part (20) of the ski. Said second rear portion extending forwards from the vicinity of the rear contact line (12) over a more or less long distance (Lr). Thus, the length (Lr) can be between 5 and 30%, and for example be 18% for a ski of length (L) equal to 2 meters. The upper surface (6) of the second rear portion (22) is therefore limited laterally by two edges constituted by two segments (EF, GH) rectilinear and parallel, distant from each other by a constant distance (Ir) less than (lc). Since the rear portion, where the width of the upper surface is constant, extends over a more or less long distance, said rear portion is connected to the central part by a rear intermediate connection portion (24) whose surface upper is limited laterally by two lateral edges (7ir, 8ir) divergent towards the front formed by the two segments (BE) and (DG) converging towards the rear.

According to an additional characteristic, the front part (18) consists of two separate portions (25, 26): a first intermediate portion (26) connecting to the central part (17) and a second front portion (25) as in this, the upper surface of the ski has on the one hand a width (la) less than the width (Ic) of the central part (17), and is on the other hand, limited laterally by two lateral edges (7a, 8a) extending rectilinearly and parallel to one another. Thus, said width (la) is constant over the front portion (25) of the front part (18) of the ski. Said front portion (25) extending rearwardly from the vicinity of the front contact line (11) over a more or less long distance (La). Thus, the length (La) can be between 8 and 45%, and for example be 22% for a ski of length (L) equal to 2 meters. The upper surface (6) of the front portion (25) is therefore limited laterally by two edges constituted by two segments (IJ, HL) rectilinear and parallel, spaced from each other by a lower constant distance (la) to (lc). Since the front portion, where the width of the upper surface is constant, extends over a more or less long distance, said front portion is connected to the central part by an intermediate front connecting portion (26) whose surface upper is limited laterally by two lateral edges (7ir, 8ir) converging towards the front formed by the two segments (JA) and (LC) converging towards the front.

According to an additional characteristic and in order to allow the lower surface (3) to be connected to the upper surface (6), while taking account of variations in thickness (e) and in width (I) of the upper surface (6) , the lateral faces (9, 10) are inclined to converge upwards at least in the front (18) and rear (20) parts to form an acute angle (A) to adapt to variations in width (I) of the upper and also lower surface of the ski.

According to a preferred arrangement, the width (I) of the lower surface being greater than the width of the upper surface at any point considered along the length of the ski, the lateral faces (9, 10) are also inclined in the central zone and the he inclination is variable along the ski. Indeed, the value (A) of the angle of inclination varies depending on the longitudinal position of the section considered, as shown in Figures 3, 4, 5, 6, 7, 8, 9 and more particularly the figure 10. Note also that advantageously, the angle (A) is greater in the central part than in the front and rear parts. Furthermore, the variation in inclination is advantageously continuous and progressive with a decrease in the constant progressive angle (A) from the center of the ski towards the ends. In the preferred embodiment and shown in FIGS. 1 to 9, the lateral faces (9, 10) are symmetrical to one another with respect to the vertical longitudinal median plane (P) of symmetry of the ski, but of course, it could be otherwise.

In the central part (17), the angle (A) is for example between 55 and 90 while in the front and rear parts, this angle will for example be between 15 and 90 _° . The side faces (9, 10) can be flat, as shown in Figures 3 to 9, but they can have a concave or convex curvilinear profile, as shown in Figures 11 and 12. Of course, the side faces can be flat in one part of the ski and be curved in one or other of the parts, or vice versa.

FIG. 10 shows an example of a curve for varying the angle (A) of inclination as a function of the position along the ski (1). The values of the angles (A) are referenced on the ordinate, while on the abscissa, there is the position considered along the ski (1).

FIG. 13 illustrates a variant of a ski in a cross section, according to which the lateral edges of the upper surfaces (6) of the front (25) and rear (22) portions include, over at least part of their length, protrusions longitudinal (70, 80), in particular to protect the upper surface (6) which is particularly attacked in these places, for example by strokes from the edges.

In the example of Figure 14, the longitudinal projections extend over the entire length of the front portion (18) and over the entire length of the rear portion (20). In the example of FIG. 15, the projections only extend over a part only of length (LD) and (LE) of the front (25) and rear (22) portions, of respective lengths (La) and (Lr ).

In addition, the structure of the ski can be of the sandwich type or of the box type or of any other type. In Figures 16, 17 and 18, there is shown by way of example, a preferred structure comprising a first upper rigid reinforcement (30) in the form of a shell with inverted "U" section forming a top wall (31) and two walls lateral (32 and 33), covering a core (34), the assembly being closed at its lower part by a lower element (35) comprising the metal edges (36, 37), a sliding layer (38) generally made of polyethylene as well as lower reinforcement elements (39, 40). An upper surface layer (41) covering the upper reinforcement to form the decoration and ending the aesthetic appearance of the ski. Advantageously, a second upper reinforcement layer (42) is provided under the first layer. Said second layer (42) being for example constituted by a strip of constant width (l'b) extending at least in the central part (17) of length (L'c) intended to receive the fasteners.

FIG. 16 representing a section of the structure of the ski in the front part (18) of the ski shows that the second layer (42) extends beyond the central part (17) while maintaining a constant width. In this case, the width (l'b) is greater than the width (la) of the upper surface of the ski and the edges (420, 421) of the second layer (42) are slightly curved upwards inside. grooves formed by the longitudinal projections (70, 80), thus reinforcing these.

The reinforcing layers (30, 39, 40) can be of any type such as layers of composite materials such as fiberglass, carbon fiber with epoxy or polyester resin, or a metal alloy. The core (34) can be filled or unloaded foam, wood or aluminum honeycomb. The surface layer (41) providing the decoration can be made of polyamide. or other such as in thermoplastic material. It can be monolayer or made up of several layers.

According to the embodiment proposed in FIGS. 1 to 10, the width (la) of the upper surface (6) of the front portion (25) is equal to the width (Ir) of the upper surface (6) of the rear portion (22), but it could be otherwise and the two widths (la) and (Ir), while being less than the width (la), could be different from each other. Thus the width (la) of the upper surface (6) of the front portion (25) could be less than or greater than the width (Ir) of the upper surface (6) of the rear portion (22).

In the embodiment described above, the upper surface of the ski (6) has been represented in the form of a flat surface. But it goes without saying that this surface could have any other shape and in particular be curved, and in this case, either convex, or concave, or then constituted by a succession of surfaces of all kinds.

Similarly, there has been shown in the previously described modes intermediate connecting portions (24, 26) connecting the front (25) and rear (22) portions to the central portion (17) and which are materialized by two lateral edges (7 , 8) marked in such a way that these extend continuously along the ski. It may be otherwise without departing from the scope of the invention and provision may be made for the lateral edges (7, 8) to have a discontinuity at the intermediate connecting portions (24, 26).

By discontinuity, it should be understood that the anterior part of the lateral edge does not connect directly to the posterior part of the lateral edge in the intermediate connecting portion. For example, the lateral edge may fade in this region if a tangent connection radius is provided connecting the lateral faces (9, 10) to the upper face (6), or can deviate if a radius intersecting with the upper surface (6).

Of course, the invention is not limited to the embodiments described and shown by way of examples, but it also includes all the technical equivalents as well as their combinations and other variants are also possible without departing from the scope of the invention.

Claims (11)

1. Ski (1) having the shape of an elongated beam (2) comprising a lower sliding face (3) bounded laterally by two lower edges (4, 5), an upper face (6) bounded laterally by two upper edges (7, 8) and two side faces (9, 10), and consisting of a central part (17) extended at the front (AV) by a front part (18) terminated at its front end (13) by the tip (14) and extended at the rear (AR) by a rear part (20) terminated at its rear end (15) by the heel (16), characterized in that said front part (18) is constituted by a portion front (25) connected to the central part (17) by an intermediate front connection portion (26), while said rear part (20) is constituted by a rear portion (22) connected to the central part (17) by a intermediate rear connection portion (24), and in that the two upper edges (7c, 8c) of the upper surface upper (6) are parallel in the central part (17), while one of the two front or rear portions (22, 25) is such that in this zone, on the one hand the lateral faces (9, 10) are inclined to converge upwards and on the other hand, the upper surface (6) is narrower than in the central part and has a constant width (la, Ir). 2. Ski according to claim 1, characterized in that the front portion (25) is such that its upper surface (6) is narrower than in the central part (17) and is limited by the two lateral edges which are parallel ( 7a, 8a - 7r, 8r). 3. Ski according to claim 1 or 2, characterized in that the rear portion (22) is such that its upper surface (6) is narrower than in the central part (17) and is limited by the two lateral edges which are parallel (7a, 8a - 7r, 8r). 4. Ski according to claim 3, characterized in that the width (la) of the upper surface (6) of the front portion (25) is equal to the width (Ir) of the upper surface (6) of the rear portion (22). 5. Ski according to claim 3, characterized in that the width (la) of the upper surface (6) of the front portion (25) is different from the width (Ir) of the upper surface (6) of the rear portion (22). 6. Ski according to claim 5, characterized in that the width (la) of the upper surface (6) of the front portion (25) is greater than the width (Ir) of the upper surface (6) of the rear portion (22). 7. Ski according to claim 5, characterized in that the width (la) of the upper surface (6) of the front portion (25) is less than the width (Ir) of the upper surface (6) of the rear portion (22). 8. Ski according to any one of the preceding claims, characterized in that in the rear (20) and front (18) parts, the lateral faces (9, 10) are inclined to converge upwards. 9. Ski according to claim 8, characterized in that the inclination angle varies continuously so that said inclination angle (A) gradually decreases from the center towards the ends. 10. Ski according to any one of the preceding claims, characterized in that it is constituted by a core (34) disposed between two reinforcements, at least one upper reinforcement (31) and at least one lower reinforcement (40). 11. Ski according to claim 10, characterized in that the upper reinforcement has the shape of an inverted U and comprises an upper wall extended on each side downwards by a side wall extending downwards.

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