FR2781166A1 - Snow ski with overhanging platform ends - Google Patents

Abstract

The snow ski comprises a rigid height raising platform (8) for the boot fixings. The front (11) and rear ends of the platform overhang its central part. It is fitted with elastomer wedges (17) under the overhang (19) of complementary shape to the overhang which provide, as a function of the ski deformation, an additional progressive support between the ski and a part of the platform overhang.

Description

SNOW SKI COMPRISING A PLATFORM INCLUDING

  LONGITUDINAL ENDS ARE OVERFLOW

  The present invention relates to a snow ski which comprises a platform

  rigid form of elevation of the shoe bindings, this platform having its front and rear ends which are free and cantilevered from its

  central part which, however, rests on the central part of the ski.

  In addition to the foot elevation function justifying the use of a platform

  shape, an additional function is sought to suppress the pushing effect exerted by the bindings on the sole of the boot, modifying the shape of the ski. This unclamping function eliminates the parasitic effect of over-arching the ski which is normally caused by the pushing of the heel piece on the sole of the boot, because this over-arching effect generates an artificial stiffening of the ski. As a ski is very precisely adjusted to obtain an optimal pressure distribution on snow that one does not want to see modified by a parasitic effect due to the bindings of the boot, the fact of now making the bindings support by an intermediate platform advantageously makes it possible to make the behavior of the ski practically independent of the adjustment of the thrust of the

  fastenings on the sole of the shoe.

  In addition, this platform having a large length, of the order of for example 500 millimeters, and being made of a rigid material, it often has the drawback of stiffening the skate area of the ski. The fact of adopting a platform having its front and rear ends free and in cantilever with respect to its central part which, on the other hand, rests on the central part of the

  ski, greatly reduces this harmful effect of stiffening the ski.

  As a state of the art in snow skiing which comprises a rigid platform for raising the bindings of the boot, this platform having its front and rear ends which are free and cantilevered with respect to its central part which, on the other hand, rests on the central part of the ski, can be cited the documents US-A-5,474,321, EP-A-0.744.194 (figure 12) and EP-A-0.744.195 (figure 13). According to these last two documents, these are the

  side edges of the ski which support the platform.

  Figures 1 and 2 attached are respectively a cross section

  median and a side view of the central part of a ski comprising a platform

  form of this type. This is a so-called "half-shell" ski and designed according to the principle

  "DUALTEC" (Trademark registered by the Applicant).

  This ski comprises, in addition to a gliding sole 1 bordered by metal edges 2, 3, a core 4 of polyurethane obtained by injection, lower 41 and upper 42 fiber reinforcements, and an upper part composed of a plastic shell 5 which rests , like the upper reinforcement 42, on edges

reinforcement sides 6 and 7.

  In accordance with document EP-A-0.744.194, a rigid platform for receiving shoe bindings, front stop and rear heel rests, by wide lateral legs 9 and 10, on the lateral edges of

reinforcement 6 and 7.

  This platform 8 has a section in the shape of an "inverted U" in its central part 14, and its front and rear ends 11 and 12 are free, in

  the absence of side feet such as feet 9 and 10, and they are located above

  above the upper surface 13 of the ski, cantilevered with respect to this

surface 13.

  This kind of platform with overhang nevertheless has two drawbacks. One way to initiate a turn is to carry the body weight of the skier towards the front of the ski and towards the inside of the turn, which, among other things, normally creates a moment of rotation around the toe of the boot, which moment of rotation being defined by a force exerted from bottom to top at the heel of the binding and by a lever arm corresponding to the length of the sole of the shoe. This moment promotes the desired effect of bending the ski at the start and during the turn. It is obvious that now, with this kind of platform with front and rear overhang, this torque is much lower than before, because the platform no longer rests on the ski than over a short longitudinal span, so that this advantageous bending aid effect of the ski is practically no longer obtained during the

initiation of a turn.

  Furthermore, if the support exerted by the skier remains centered relative to the relatively small surface of support of the platform on the ski, it can be exerted, due to this small support surface, considerable pressure on the structure of the ski during brutal flexions of this ski. These pressures involve risks of rupture of the ski structure. In this case, this type of cantilever platform generates an effect of discomfort due to the insufficient

  the shock absorption following such brutal bending.

  The object of the invention is to overcome these drawbacks, as well as to improve the performance, especially in competition, of a ski of this type. It would in fact also be desirable, particularly during a turn where the curvature of the ski is large, to automatically modify the position of the point of application of the resultant of the force exerted by the skier as a function of the deformation of the ski and therefore the amplitude of the turn. It would also be desirable for this displacement of the point of application of the load to be accompanied by a variation in the surface

  effective support of the rigid platform on the ski.

  The invention relates for this purpose to a snow ski which comprises a rigid platform for raising the bindings of the boot, this platform having its front and rear ends free and cantilevered relative to its central part which is based on the ski, this ski and this platform being characterized in that they are equipped with additional progressive support means, in

  function of the ski deformation, between the ski and at least part of the door-to-door

platform scythe.

  The invention will be well understood, and its advantages and others

  characteristics will emerge well, during the following description of an example not

  limiting of embodiment, with reference to the appended schematic drawing in which: Figure 3 is a top view, platform removed, of a ski according to Figures 1 and 2, but equipped in accordance with the invention * Figure 4 is a section partial longitudinal, according to IV- IV of FIG. 3, of the assembly constituted by the ski and its platform * FIG. 5 shows, in partial longitudinal section, the principle of

  progressive deformations with cooperation of the ski and its platform

  shape, during a simple flexion movement of the ski * Figures 6 and 7 are, respectively in partial longitudinal section, a first practical example of embodiment of the front part of the platform, the wedge of the invention being glued to the surface of the ski, and the dimensioned drawing of this wedge in Figures 8 and 9 are, respectively in partial longitudinal section, a practical example of another embodiment of the rear part of the platform, the wedge of the invention being glued to the surface of the ski, and the dimensioned drawing of this wedge * Figure 10 is a view similar to Figure 8, and showing another practical example of embodiment * Figure 11 is a view similar to Figure 10, and illustrating a first variant * Figures 12 and 13 are respectively cross sections along XII-XII and XIII-XIII of Figure 11 * Figure 14 is another view similar to Figure 10, and illustrating a second variant * Figure 15 and 16 are respectively sections transve rsales according to XV-XV and XVI- XVI of Figure 14 * Figure 17 is a view similar to Figure 10, and illustrating another alternative embodiment

  * Figures 18 and 19 illustrate, in cross section along XVIII-

  XVIII of Figure 17, two particular embodiments.

  Referring to all of Figures 1 to 4 and 6 to 9, it is added, on the classic ski already described above and corresponding to Figures 1 and 2, four shims (or cams) of hard elastomer 15 to 18, including two lateral wedges 15, 17 under the front overhang 11 of the platform 8, and two lateral wedges 16,18 under the rear overhang 12 of this platform 8. Each of these wedges or cams has, according to Figure 4, a longitudinal section 17 which adopts a fairly similar shape to the section of an aerodynamic wing of an aircraft, and which is in fact intended to become progressively conjugate, as the ski deforms during a bending, along arrow F, of this ski to come into additional bearing contact with the lower face 19 of the corresponding overhang 11 of

platform 8.

  In this way, the range of the platform 8 on the ski gradually increases, which in particular increases the above-mentioned moment of rotation. In fact, during the turn, the skier's body being carried forward and towards the inside of the turn, the invention allows, when the characteristic wedges are located under the front overhang, on the one hand advancing the contact area with the ski and on the other hand increasing the support surface S, therefore the lever arm component of the moment of rotation, which effectively implements the general means defined above, according which is imparted, as a function of the deformation of the ski and of the position of the skier, an additional progressive support S ′, the result of which is

  it also gradually moves towards the front of the ski, getting closer to the

overhang of the platform.

  This general means, as implemented in this exemplary embodiment, is very well illustrated in FIG. 5 which shows what happens when the ski bends more and more: * In position 20, the ski does not is not flexed, and platform 8 is

  completely cantilevered, at the front 11, as at the rear 12.

  * In position 21, the bending is medium, and the overhang, before and

  rear, decreased by about half.

  * In position 22, bending is important, and the front 11 and rear 12 parts are completely supported on the above-mentioned shims, so

  that this platform 8 no longer has any door-to-door

  false. As an indication, the shims 15 to 18 are, in this embodiment, made of hard elastomer. They preferably have a hardness of between 50 shores A and 50 shores D. Of course, the invention is not limited to this exemplary embodiment. The front chocks 15 and 17 and / or rear 16 and 18, can each be combined into a single chock taking the entire width of the ski: a chock with

  the front and / or a wedge at the rear.

  There may be, as well for the elastomer wedges as for the overhangs 11 and 12, asymmetrical designs, as well in right / left asymmetry as in front / rear, these asymmetries being asymmetries of shape and / or asymmetries in the material of the wedges. The increases in

  range, in the event of bending of the ski, would then be asymmetrical.

  Instead of being made of hard elastomer, which generates a certain comfort at the expense of a little efficiency, the wedges could, which would be optimal in efficiency, be made of a rigid material, for example metallic. They could only be provided towards the front of the platform. Conversely, they could, in particular to favor the technique, known as "swallowing", of initiating turns by pressing on the rear of the ski and not on the front,

  only be provided towards the rear of the platform.

  In order not to stiffen the ski in flexion, the wedges could, as shown in FIG. 8, have lateral notches intended to give them flexibility. Finally, as illustrated in FIGS. 10 to 16, to which reference will now be made, the cleats may not be fixed to the ski, but be

  fixed under the cantilever part (s) before and / or rear of the platform.

  In Figure 10, which is the counterpart of Figure 8, we see that the wedge 18 is reported under the front overhang 12 of the platform. This wedge has, of course, an inverted shape with respect to that of FIG. 8 so as to obtain the effect of the invention. It is of course the same for the other three

holds 15 to 17.

  According to Figures 11 to 13, there is provided, under the front overhang 12 of the platform, a single axial shim 28 which has the same shape as the shim 18 of Figure 10, but which is integrated into the platform -form instead of being reported under the latter. It is for example the same at the front of the platform where a single axial wedge 27 is provided. The structure of the ski, not detailed, is designated by the reference 25

on cross sections.

  According to Figures 14 to 16, this is a variant of the embodiment according to Figures 11 to 13, for which the single and axial shim 28 is replaced by two lateral shims 36 and 38 which are also integrated in the plate -form. he

  the same applies, for example, to the front of this platform.

  Finally, like Figures 6 and 8, the wedges 17 and 18 could be an integral part of the ski structure as shown in Figures 17 to 19 o the boss 50 replaces the central wedge in Figure 18, or is arranged to leave and

  other of the ski in 51 and 52 according to Figure 19.

Claims (12)

  1- Set consisting of a snow ski and its rigid platform   (8) for raising the shoe bindings, this platform   form (8) having its front (11) and rear (12) ends free and cantilevered with respect to its central part (14) which, for its part, rests on the ski, characterized in that it is equipped additional progressive support means, depending on the deformation of the ski, between the ski and at least part of the overhang (11, 12) of the platform (8).   2- ski / platform assembly according to claim 1, characterized in that said means are means (15-18) with forms complementary to the progressive deformation in bending of the ski. 3- ski / platform assembly according to claim 2, characterized in that these means consist in providing shims (15-18), or cams, under the front (11) and rear (12) overhangs, these wedges having a profile (17) intended to become gradually conjugated, as the ski deforms during bending, of the lower surface (19) of the overhang   corresponding (11) of the platform (8).   4- ski / platform assembly according to claim 3, characterized   in that these shims or cams (15-18) are made of elastomer.   - Ski / platform assembly according to claim 4, characterized in that the hardness of these elastomer shims (15-18) is between 50 shores A and 50 shores D. 6- Ski / platform assembly according to claim 3, characterized in that these shims or cams (15-18) are made of a rigid material. 7- Ski / platform assembly according to claim 6, characterized   in that these shims or cams (15-18) are metallic.   8- ski / platform assembly according to one of claims 3 to 7,   characterized in that these shims or cams (15-18) are provided with   the front as well as the back of the platform.   9- Ski / platform assembly according to one of claims 3 to 7,   characterized in that these shims or cams (15-18) are provided   only at the front of the platform.   - Ski / platform assembly according to one of claims 3 to 7,   characterized in that these shims or cams (15-18) are provided   only at the back of the platform.   11- ski / platform assembly according to claim 8, characterized in that these wedges or cams (15-18) are provided in a   symmetrical front / rear configuration.   12- ski / platform assembly according to claim 8, characterized in that these wedges or cams (15-18) are provided in a   asymmetrical front / rear configuration.   13- Ski / platform assembly according to one of claims 3 to   12, characterized in that these shims or cams (15-18) are provided in an asymmetrical right / left configuration of the same ski.   14- Ski / platform assembly according to one of claims 3 to   13, characterized in that these shims or cams (15-18) are   positioned on the ski surface.   - Ski / platform assembly according to claim 14, characterized in that the wedges (50-52) are an integral part of the structure ski.   16- Ski / platform assembly according to one of claims 3 to   , characterized in that these shims or cams (15-18) are   positioned under the cantilevered part (11-12) of the platform   form. 17- ski / platform assembly according to claim 16, characterized in that these wedges or cams (15-18) are reported under this cantilevered part (11, 12).   18- Ski / platform assembly according to claim 16, characterized in that these wedges or cams (27, 28, 36, 38) are integrated into   this part is cantilevered (11, 12).   19- Method for producing an assembly consisting of a snow ski and its rigid platform (8) for raising the bindings of the boot, this platform (8) having its front (11) and rear (12) ends ) which are free and cantilevered with respect to its central part (14) which, on the other hand, rests on the ski, characterized in that one confers, depending on the deformation of the ski and the position of the skier, additional progressive support, the result of which also moves progressively, between the ski and at least one part   of the overhang (1,12) of the platform (8).