FR2808698A1 - SKI PLANNED FOR THE PRACTICE OF ALPINE SKIING - Google Patents

Abstract

The invention relates to a ski intended for alpine skiing, comprising a body, front and rear ends, a gliding sole (6) surmounted by at least one lower reinforcing layer (9), a core ( 12) and at least one top reinforcing layer (16) .It is characterized in that the core has a central core (18) of hard material which extends over part of the length and width of the ski, and a border (22) of softer material which borders the core on the sides, front and rear.

Description

SKI PLANNED FOR THE PRACTICE OF ALPINE SKIING

  The invention relates to a ski intended for alpine skiing. In a known manner, a ski is presented as an elongated beam having on its lower face a gliding sole, and receiving on its upper face provided retaining elements

  to hold the skier's shoe.

  The pressure distribution of the ski on its sliding surface is an important parameter which determines the qualities of

  skiing and cornering.

  Many solutions have been proposed to better

  control this pressure distribution.

  Among these solutions, that described in patent application EP 938 917 proposes to mount the retaining elements on two oscillating plates connected to the ski by transverse articulation axes which pass through the structure of the

  ski. The plates are linked together by a link.

  Such a construction gives good results. However, it is more suitable for skis that are relatively narrow

  at the level of the skate, that is to say the central part of the ski.

  An object of the invention is to propose a construction of

  same type which is better suited for wide skis.

  The ski according to the invention comprises an elongated body, front and rear ends, a gliding sole topped by at least one lower reinforcement layer, a core and at least one upper reinforcement layer. It is characterized by the fact that the core has a central core of hard material which extends over part of the length and width of the ski, and an edge of softer material which

  borders the soul on the sides, front and back.

  According to a secondary characteristic, the central core projects in the direction of the height with respect to the rest of the core. According to another secondary characteristic, the ski is surmounted by two oscillating plates having an upper mounting surface intended to receive retaining elements, the plates being assembled to the ski around an axis

  transverse carried by the core core.

  The invention will be better understood by referring to the

  description below and attached drawings attached to it

  attached. Figure 1 shows in perspective a bare ski according to the present invention. Figure 2 is a sectional view of the ski of Figure 1 to

level of its central area.

  Figure 3 is a sectional view of the ski of Figure 1

towards one of its ends.

Figure 4 shows the core core.

  Figure 5 shows the central area of the ski in Figure 1

fitted with plates.

  Figure 6 is a cross-sectional view of the ski at

level of one of the plates.

  The ski 1 which is represented in FIG. 1 comprises a body

  elongated 2, with two front and rear ends 3 and 4.

  The front end 3 is raised and rounded to form a spatula. In the illustrated embodiment, the rear end 4 is also raised and rounded. This however is not limiting, and one could have an end

  cut straight as for a traditional ski.

  In known manner, the ski 1 has in its lower part a sliding sole 6. The sole is bordered laterally by

two side edges 7 and 8.

  The gliding sole 6 is surmounted by a reinforcing layer 9 made of fiber-reinforced resin, itself preferably surmounted by a metallic reinforcing layer 10, made in particular of aluminum. These different layers are housed

between edges 7 and 8.

  Above this lower sub-assembly is the core 12 which will be described in detail below. Above the core is preferably a layer 14 of metallic reinforcement which is of the same nature as the layer 10. If the layer 10 is present, in principle the layer 14 is also present. Finally an upper reinforcement layer 16 made of resin reinforced with a layer of

  fibers cover the whole like a shell, that is

  say that this layer descends along the side flanks to the side edges. Preferably, as can be seen in FIGS. 3 and 4, the edges extend on each side over a small width, and the upper reinforcing layer 16 descends until contact with these parts

overflowing that it covers.

  Conventionally, a bonding film is interposed between the metal reinforcing layers if they are present and the core. These layers have not been shown in the figures. In addition, the upper reinforcing layer is covered with a decorative layer which is also not shown in the figures. This decorative layer is

of any suitable and known type.

  According to the invention, the core 12 comprises two main parts of a different nature. First, the core 12 has a central core 18 made of a relatively hard material, such as wood. The central core extends over a portion

  only the length and width of the ski.

  According to the illustrated embodiment, the central core rests in the direction of the height on the lower sub-assembly, that is to say on the metal reinforcing layer 10. And it protrudes upward from the rest of the nucleus. Thus, in Figure 1 the projecting edge 19 is formed by the central core of the core covered with the upper reinforcing layers. In the central part of the ski, the projecting ridge is relatively wide. Its width is close to that of a traditional ski, about 60

  millimeters. This value is not limitative.

  Figure 4 shows in perspective the core 18 of the core.

  It is formed for example by an elongated block of wood. The block is refined in the width direction towards each of its ends 18a and 18b. In these areas, its thickness is also reduced by machining its upper part. In its middle part 21, the core 18 has lateral edges and faces

  upper and lower substantially parallel.

  As has been said previously, the core is preferably made of wood, for example in strips of beech and

  poplar glued and it is shaped by machining.

  The rest of the core which forms the edge 22 of the core 18 laterally, on the front and the rear is made of a softer and lighter material than the core. For example, the border is made of polyurethane foam, possibly reinforced with glass fibers. This border is for example made from a foam bar cut or machined to the desired shape, with a central cut in which the core is housed. The central core and the border define two zones of very distinct altitude skiing. To take this into account, preferably, the metal reinforcing layer 14, if it is present, is formed from two parts, an edge part 14a which covers the edge of the core and which has a central cut through which the core 18 passes, and a central part 14b which covers the upper face of the central core 18 of the core in

marrying its shape.

  The section of the ski shown in FIG. 2 is produced in the central zone, where there is the core 18 and the edge 22 of the core side by side. The section of Figure 3 is made towards one or the other of the ends where the core is formed

only by border 22.

  A ski was produced according to this construction method having the following dimensions, length 1950 millimeters, maximum width in tip 120 millimeters, minimum width in the central area 86 millimeters, maximum width in heel 115 millimeters, with a core having a core of 1200 millimeters long, 60 millimeters wide, projecting 8 millimeters towards the middle and 1.5 millimeters towards the ends relative to the rest of the core, the thickness of the ski being 12 millimeters in these border areas. Naturally, these figures are given by way of example only and have no

limiting value.

  To support the retaining elements of the boot, the ski of the invention is preferably equipped with two plates 23 and 24. The plates have the same construction, with an upper mounting face 23a, 24a which is intended to be pierced and receive front and rear retaining elements of a known type. The mounting faces 23a and 24a are kept slightly raised relative to the upper surface of the ski. The plates overlap the edge 19 of the ski. They are each formed for example by an aluminum plate or the like which is folded to the width of the edge 19 so as to form two lateral wings which descend along the

sides of the ridge 19.

  Thus the plate 23 which is shown in section in FIG. 6 has two lateral wings 23b, 23c which run along the edge 19. Each of the wings is pierced with an orifice traversed by a screw which is screwed into the core. The assembly screws of a plate are screwed in alignment with each other, so as to define for the plate a transverse axis of oscillation which crosses the core of the core. Alternatively, instead of the screws, one could have a stud or the like which passes through the structure of the ski. We could also use

  inserts housed in the ski structure during its manufacture.

  To allow the passage of the screw heads at the time of assembly, preferably, the ski has in the edge border area four transverse grooves of shallow depth 26, 27, 28, 29 in alignment with the housing of the screws. The depth of the grooves is determined to allow the passage of the screw heads. In addition, against the ridge, the ski has a small recess at each of the screw housings, to allow the housing of the plate wing. The recesses 34 and 35 for the wings 23b and 23c are visible in FIG. 6. These different reliefs of the ski are shaped by cutting or machining the core, or another suitable means. Preferably, the metal reinforcing layer 14

  is shaped to match these reliefs.

  Above the edge 19, thin plates 30, 31, 32, 33 of a deformable material, for example made of elastomer, are interposed between the mounting faces of the plates and the upper surface of the edge. You can make the pads with a different hardness, in this case, preferably, the inner pads 31 and 32 are harder than the outer pads 30 and 33. The pads fill

  the space between the frames and the ski.

  When sliding, the two-part core allows better pressure spreading. Indeed, the wooden core stiffens the central part of the ski where most of the pressure forces are concentrated. It acts like a beam which spreads over its entire length the support forces of the boot which are concentrated at the connections between the plates and the ski. As a result, the pressure peaks that are usually encountered towards each connection or each retaining element are attenuated. In addition, the oscillating plates which carry the retaining elements of the boot release the ski in flexion and ensure a better winding of the ski in the curves, hence a better handling of the ski. The part of the core which is foam gives the ski lightness, and also a certain flexibility. It is possible in this way to build very wide skis, especially in the central area. These skis have a great lift, given their sliding surface. They nevertheless have great maneuverability thanks to the construction

  particular to the core and to the articulated plates.

  Naturally this description is given only

  indicative, and one could adopt other implementations of the invention without departing from the scope thereof. In particular, the core of the hard material core could occupy only part of the thickness of the core. On the other part of its thickness, the core would be formed by the same material as the border, in particular polyurethane foam. In this case, the core core would not be in direct contact with the lower sub-assembly of the ski, but would nevertheless retain its function of spreading the pressure on the

sliding surface.

  Another method of mounting the retaining elements could also be implemented. For example, the elements could be assembled directly on top of the edge 19 by taking advantage of its great width. Under these conditions, we could reduce the difference in altitude between the top of the ridge and the rest of the ski. Ultimately, the soul and the border

  could have substantially the same thickness.

Claims (9)

  1- Ski intended for alpine skiing, comprising an elongated body (2), front and rear ends (3, 4), a sliding sole (6) bordered by two lateral edges (7, 8) and surmounted by '' at least one lower reinforcing layer (9), a core (12) and at least one upper reinforcing layer (16), characterized in that the core has a central core (18) made of hard material which extends over part of the length and width of the ski, and an edge (22) of more material   soft which borders the soul on the sides, the front and the back.   2- Ski according to claim 1, characterized in that the core (18) of the core protrudes relative to the edge (22) in the height direction, so as to form   the upper surface of the ski a projecting edge (19).   3- Ski according to claim 2, characterized in that the core (18) of the core projects 1.5 to 8 millimeters relative to the border (22).   4- Ski according to claim 1, characterized in that the core (18) is made of wood and the edge (22) of the core is made of   polyurethane foam reinforced with fibers.   - Ski according to claim 1, characterized in that the edges (7, 8) project laterally, and that the upper reinforcement layer (16) descends along the lateral sides of the ski to the edges (7, 8) of which it covers the overflowing part.   6- Ski according to claim 1, characterized in that the core core extends between the reinforcing layers upper and lower.   7- Ski according to claim 1, characterized in that the core of the core extends over only part of the height of the core between the reinforcing layers upper and lower.   8- Ski according to claim 2, characterized in that it is surmounted by two plates (23, 24), each having a mounting face (23a, 24a) provided for a shoe retaining element, two lateral wings (23b, 23c) which descend along the edge, that the mounting faces of the plates are raised relative to the upper surface of the edge (19), and that the plates are mounted oscillating   around a transverse axis which crosses the core of the core.   9- Ski according to claim 8, characterized in that each of the plates is assembled to the ski by screws screwed into the core (18) of the core. - Ski according to claim 6, characterized in that plates (30, 31, 32, 33) of elastically deformable material are interposed between each plate (23, 24) and   the upper surface of the edge (19).   11- Ski according to claim 6, characterized in that it has a length of 1950 millimeters, and a minimum width of 86 millimeters in its central zone, and that the core of the core measures 1200 millimeters long and 80 millimeters wide in its central part.