FR2739300A1 - CROSS-COUNTRY SKIING, PARTICULARLY FOR THE PRACTICE OF SKATING - Google Patents

Abstract

The attachment consists of a rigid reinforcing member (12) which fits over the middle section of the ski. It has an upper wall (13) situated above or on the upper surface of the ski, or is set in a recess in it, and two side walls (14a, 14b) which fit against or are recessed in the sides of the ski, pressing against its lower surface covering skin. The side wall (14b) of the reinforcing member on the outside of the ski has its rear edge (16b) swept backwards, while the opposite side wall (14a) has its front edge (16a) swept forwards. The ski reinforcing member is made from a lightweight metal alloy, or from a composite material based on reinforcing fibres and resin. It can be secured to the ski by an adhesive such as a visco-elastic film, or by screws, riveting or welding.

Description

The present invention relates to cross-country skiing, in particular

for the practice of skating.

  For the practice of cross-country skiing, two progression techniques

are currently being implemented.

  In a ski, the interior and exterior terms are defined taking into account a pair of skis, the interior term being used for the part of the ski located directly opposite the other ski, while the

  external term is used to designate the part located on the opposite side.

  The oldest and most traditional technique is that of the alternative step, in which the two skis are moved alternately

  in two parallel tracks made in the track.

  The second technique, more recent, is that of the skater's step, more generally called skating. In this case, the skier progresses by successively resting on the snow on each of his two skis, and making them diverge forward. The movement carried out each time a ski is pressed on the snow and broken down into four successive phases: a first phase in which the ski is supported on the snow in an area located on the outside of the ski and at the rear of the binding , a phase of sliding flat on the snow, a phase of impulse on an area located on the interior side and in front of the binding, and a last phase during which the ski leaves the snow before

  regain support in accordance with the first phase.

  For the implementation of the skating technique, it is necessary to use shoes which, if they allow articulation on the ski at the front end of the sole, have a sufficiently rigid sole and a rod associated with a collar hugging the bottom of the tibia, to allow a good transmission of the forces for the implementation of the four phases defined above. A shoe particularly suitable for skating is described in document FR A 2 697 141 in the name of the Applicant. A cross-country ski has a front end called a tip, a rear end called a heel and a central part or skate area, the upper face of which is intended to receive a binding for a shoe. The inner side of the ski is constituted by a side wall arranged when a pair of skis is in use, opposite the corresponding side wall of the other ski, and an outer side formed by the

second side wall of the ski.

  Traditionally, a cross-country ski comprises a lower assembly composed of a sole bordered with edges, possibly a reinforcing element, and an upper assembly composed of at least one filling core, an upper wall and side walls. , and

  possibly a reinforcing element.

  It is possible, as described in document FR A 2 590 179, to equip the inside of the ski, in the central part or skid area thereof, with a profiled element whose ends are curved downwards , like shovels, which cut the plane containing the neutral fiber of the ski. This provision aims to avoid floating of the front and rear ends of the ski, and to stiffen it to ensure good transmission of the force of the skier's foot at the inside edge of the ski. The

  making this ski is complex and therefore expensive.

  The object of the invention is to provide a cross-country ski having excellent efficiency by taking account of the successive phases of support on the snow during the practice of skating, without however requiring a

  too expensive manufacturing of the entire ski.

  To this end, the ski which it concerns, of the aforementioned type, comprises, in the central part or skid zone of the ski, a rigid reinforcement element having an upper wall, either located above the upper wall of the ski, either resting on the latter, or integrated in a zone in the recess of this wall, or finally integrated into the structure by locally replacing the upper wall, and two side walls pressed against the two lateral faces of the ski or integrated in these faces and taking support on the lower assembly of the ski, or constituting themselves the lower edges in the areas where they are located, the two side walls of the reinforcing element being offset longitudinally relative to one another, that located on the outside of the ski being offset towards the rear while that located on the inside of the ski is offset towards the front with respect to the upper wall of the element

reinforcement.

  The supports of the ski on snow, during the first phase of the skating technique take place on the outside and at the rear of the binding, while, during the impulse corresponding to the third phase, these supports s '' perform on the inside and, at the front of the binding, these

  supports follow an inclined direction relative to the longitudinal axis of the ski.

  They are thus produced in areas where the rigid reinforcing element is located. This reinforcing element improves efficiency by avoiding a twist of the ski in the central zone thereof, while making it possible to retain, for the rest of the ski, a traditional structure ensuring the desired flexibility to take account of the required performance and

  also comfort for the user.

  According to a first embodiment of this ski, the upper wall of the reinforcing element has a generally rectangular shape of width substantially equal to that of the ski and of length corresponding substantially to that of the boot, and in that the walls side of the reinforcing element each extend over at least part of the length of the upper wall and comprise, for the side wall located on the outer side of the ski, an extension towards the rear and for the side wall located inside of the ski, a

forward extension.

  Advantageously, in this case, the upper wall of the reinforcing element is intended to be equipped, at its front end, with the

  shoe fixing stop, or part of this stop.

  According to another embodiment of this ski, the upper wall of the reinforcing element is in the form of a strip inclined relative to the longitudinal axis of the ski, extending from the outside of the ski, in the zone corresponding to the support of the heel of the boot, towards the inside of the ski, in the zone corresponding to

  the support of the front part of the shoe.

  In the case of this second ski, the side walls of the reinforcing element, extending from the edges of the upper wall, have extensions respectively towards the rear for the side wall located on the outside of the ski and towards the front for the side wall

  located on the inside of the ski.

  In order to modulate the rigidity of the central zone of the ski by reducing this rigidity from the middle of the ski towards the two ends of the latter, the extensions of the side walls of the reinforcing element have heights which decrease from the zone

  central of the ski towards the extremities thereof.

  The reinforcing element may consist, for example, of a plate of light metal alloy, such as an alloy known under the brand name Zicral, or be made of a composite material based on fibers and resin. Advantageously in this case, the reinforcing fibers are inclined relative to the longitudinal axis of the ski, that is to say mainly oriented at the level of the upper wall, from the rear towards the front and from the outside towards the inner side of the ski. This provides maximum resistance in the oblique direction in which the

  efforts during the different phases of skating.

  The upper wall of the reinforcement element can be placed above the upper face of the ski, in contact with this face or at a distance therefrom, or embedded in a recessed area that comprises the upper surface of the ski, or integrated in the structure of the ski,

  by locally replacing the upper wall thereof.

  The side walls of the reinforcement element can be arranged outside the side faces of the ski or integrated into the

  structure of the ski, locally replacing the lateral faces thereof.

  The side walls of the reinforcement element can be linked to the side faces of the ski, and the upper wall of the reinforcement element can be linked to the upper face of the ski, these connections being obtainable by known means such as bonding , screwing, riveting or welding, bonding being for example carried out by

  I'intermediate of a visco-elastic film.

  In any case, the invention will be well understood using the

  description which follows, with reference to the attached schematic drawing

  representing, by way of nonlimiting examples, several embodiments

of this ski.

  Figure 1 is a perspective view of a cross-country ski for the left leg; Figure 2 is a perspective view on an enlarged scale of the reinforcing element fitted to the ski of Figure 1; Figure 3 is a top view of the ski of Figure 1, equipped with a shoe binding; Figure 4 is a cross-sectional view on an enlarged scale along the line IV-IV of Figure 3; Figure 5 is a longitudinal sectional view on an enlarged scale of the central part of another ski according to the invention; Figure 6 is a cross-sectional view, identical to Figure 4, of another ski in which the upper wall of the reinforcing element is located above the upper face of the ski; Figure 7 is a longitudinal sectional view, identical to Figure 5, of the central part of a ski, in which the reinforcing element is embedded in the structure of the ski; Figure 8 is a cross-sectional view along the line VIII-VIII of Figure 7; Figure 9 is a perspective view, similar to Figure 2, of another reinforcing member; Figure 10 is a view of a cross-country ski comprising the element of

reinforcement of figure 9.

  FIG. 1 represents a cross-country ski 2 for the left leg, comprising a central part or skid zone 3, a raised front end 4, called the tip, and a thinned and slightly raised rear end 5, called the heel. This ski comprises, as shown in particular in FIG. 4, a lower assembly composed of a sole 6 bordered with edges 7, and possibly comprising a reinforcing element not shown, and an upper assembly composed of at least one filling core. 8, a reinforcement element not shown, an upper wall 9 and side walls 10a and 10b, the side wall 10a corresponding to the inner side, that is to say to the wall located directly opposite the corresponding wall of the other ski of the same pair, while the wall

  lateral 10b corresponds to the external side.

  According to the invention, the ski 2 is equipped, in its central part, with a rigid reinforcement element 12, comprising an upper wall 13, and two side walls 14a and 14b pressed against the two side walls 10a and 10b. The connection between the reinforcing element and the ski is produced by a film 11 of visco-elastic material. The lower edges of the two side walls 14a and 14b bear on the upper face of the lower edges 7 of the ski. However, in an alternative embodiment, the edges of the ski could be interrupted at this level and the lower edges of the side faces could then themselves constitute the lower edges of the ski in the areas where they are located. The upper wall 13 of the reinforcing element 12 can bear on the upper wall 9 of the ski according to FIG. 4, or be integrated into this wall, as shown in FIG. 5. In this case, the upper face 9 of the ski has a recess 9a on the side of the core 8, allowing

  the embedding of the upper wall 13 of the reinforcing element 12.

  According to another possibility shown in FIG. 6, the upper wall 13 of the reinforcing element is located above the upper face

  9 skiing, without resting on it.

  Figures 7 and 8 show another embodiment of a ski, in which the same elements are designated by the same references as above. In this ski, the upper wall 13 and the side walls 14a, 14b of the reinforcing element are integrated in

  the structure of the ski, in contact with the core 8 or reinforcements covering it

  ci, and locally replace the upper face 9 and the lateral faces 10a,

b skiing.

  In the embodiments shown in Figures 1 to 8, the upper wall 13 of the reinforcing element has a generally rectangular shape, of width substantially equal to that of the ski and of length corresponding substantially to that of the boot. The upper wall 13 of the reinforcing element is in this case, as

  shown in Figure 3, equipped with the attachment 15 of the skier's boot.

  The side walls 14a and 14b, which extend the upper wall 13, respectively have an extension 16a towards the front, for the side wall 14a located on the inside, and an extension 16b towards the rear, for the side wall 14b located at the outside of the ski. The respective heights of the two extensions 16a and

  16b decrease towards the corresponding ends of the ski, that is to say

  say towards the tip 4 for the extension 16a and the heel 5

for the extension 16b.

  Figures 9 and 10 show an alternative embodiment of this ski in which the upper wall 23 of the reinforcing element is in the form of a strip inclined at an angle a with respect to the longitudinal axis of the ski extending from the outside of the ski, in the area corresponding to the support of the heel of the boot, towards the inside of the ski, in the area corresponding to the support of the front part of the boot. From the inclined strip 23, forming the upper wall, extend two side walls 24a and 24b, provided with extensions 26a

and 26b.

  Whatever the form in which it is presented, the reinforcing element must be rigid and preferably light, and for this purpose is produced, for example, in a plate of light metal alloy, such as Zicral, or in a composite material based on reinforcing fibers and resin. In the embodiment of Figure 9, the reinforcing fibers 27 can be inclined relative to the longitudinal axis of the ski, that is to say mainly oriented in the same direction as the band 23,

  back to front and from the outside to the inside of the ski.

  As is clear from the above, the invention brings a great improvement to the existing technique by providing a cross-country ski of simple design, the structure of which is perfectly adapted to the

  practice of the skating technique.

  As it goes without saying, the invention is not limited to the sole embodiments of this ski described above by way of example, on the contrary it embraces all the variants thereof. Thus, in particular, some of the characteristics described in the context of a combination could be implemented in the context of other combinations without

  that we therefore go beyond the scope of the invention.

Claims (14)

  1. Cross-country skiing, in particular for skating, comprising a front end (4) called the tip, a rear end called the heel and a central part (3) or skate area intended to receive a binding for a shoe, one side interior consisting of a side wall (10a) arranged, in period of use, of a pair of skis, facing the corresponding side wall (10b) of the other ski, and an exterior side constituted by the second side wall of the ski, and consisting of a lower assembly composed of a sole (6) bordered by edges (7) and possibly of a reinforcing element, and of an upper assembly composed of at least one filling core ( 8), an upper wall (9) and side walls (10a, 10b) and possibly a reinforcing element, characterized in that it comprises, in the central part or skate zone of the ski, an element rigid reinforcement (12) having an upper wall (13, 23) , either located above the upper wall (9) of the ski, or resting on the latter, or integrated into a zone in recess of this wall, or finally integrated into the structure by locally replacing the upper wall, and two walls lateral (14a, 14b; 24a, 24b) pressed against the two lateral faces of the ski (10a, 10b) or integrated into these faces and bearing on the lower assembly of the ski, or themselves constituting the lower edges in the areas where they are located, the two side walls (14a, 24a, 14b, 24b) of the reinforcing element being offset longitudinally relative to one another, that (14b, 24b) located on the outside of the ski being offset towards the rear then that the one (14a, 24a) located on the inside of the ski is offset forward relative to the upper wall (13, 23) of the reinforcing element.   2. Cross-country ski according to claim 1, characterized in that the upper wall (13) of the reinforcing element (12) has a generally rectangular shape of width substantially equal to that of the ski and of length corresponding substantially to that of the boot, and in that the side walls (14a, 14b) of the reinforcing element each extend over at least part of the length of the upper wall and comprise, for the side wall (14b) located on the side outside of the ski, an extension (16b) towards the rear and for the side wall (14a) located on the inside of the ski, an extension (16a) towards the front. 3. Cross-country ski according to claim 1, characterized in that the upper wall (13) of the reinforcing element (12) is intended to be equipped, at its front end, with the fixing stop (15) of the   shoe, or part of this stopper.   4. Cross-country ski according to claim 1, characterized in that the upper wall of the reinforcing element is in the form of a strip (23) inclined relative to the longitudinal axis (30) of the ski, s extending from the outside of the ski, in the area corresponding to the support of the heel of the boot, towards the inside of the ski, in the area   corresponding to the support of the front part of the shoe.   5. Cross-country ski according to claim 4, characterized in that the side walls (24a, 24b) of the reinforcing element, extending from the edges of the upper wall, have extensions respectively (26b) towards the rear for the side wall (24b) located on the outside of the ski and (26a) forward for the side wall (24a) located on the inside of the ski.   6. Cross-country skiing according to any one of claims 2 and   5, characterized in that the extensions (16a, 16b; 26a, 26b) of the side walls of the reinforcing element have heights which   decrease from the central area of the ski towards the ends thereof.   7. Cross-country skiing according to any one of claims 1 to 6,   characterized in that the reinforcing element (12) consists of a   light metal alloy plate, such as zicral.   8. Cross-country skiing according to any one of claims 1 to 6,   characterized in that the reinforcing element (12) is made of a composite material based on reinforcing fibers and resin, the reinforcing fibers being inclined relative to the longitudinal axis of the ski, that is to say say mainly oriented at the level of the upper wall, from the rear towards   front and from outside to inside of the ski.   9. Cross-country skiing according to any one of claims 1 to 8,   characterized in that the upper wall of the reinforcing element is placed above the upper face of the ski, in contact with this face or away from it.   Cross-country ski according to any one of claims 1 to   8, characterized in that the upper wall of the reinforcing element is embedded in a recessed area which the wall has superior of skiing.   11. Cross-country skiing according to any one of claims 1 to   8, characterized in that the upper wall of the reinforcing element is integrated into the structure of the ski, locally replacing the wall superior of it.   12. Cross-country skiing according to any one of claims 1 to   11, characterized in that the side walls of the reinforcing element   are arranged outside the side faces of the ski.   13. Cross-country skiing according to any one of claims 1 to   11, characterized in that the side walls of the reinforcing element are integrated into the structure of the ski, locally replacing the faces side of it.   14. Cross-country skiing according to any one of claims 9 to   1 1, characterized in that the upper wall (13, 23) of the reinforcing element is linked to the ski, in particular by gluing, screwing, riveting or welding.   15. Cross-country skiing according to any one of claims 12   and 13, characterized in that the side walls (14a, 14b; 24a, 24b) of the reinforcing element are linked to the ski, in particular by bonding, screwing, riveting or welding.   16. Cross-country skiing according to any one of claims 14   and 15, characterized in that the reinforcing element is glued to the ski by   through a visco-elastic film.