EP0624113A1

EP0624113A1 - Device for altering pressure distribution over the sliding surface of a ski.

Info

Publication number: EP0624113A1
Application number: EP93901808A
Authority: EP
Inventors: Joel Arduin; Masson Jacques Le
Original assignee: Salomon SAS
Current assignee: Salomon SAS
Priority date: 1992-01-31
Filing date: 1992-12-02
Publication date: 1994-11-17
Anticipated expiration: 2012-12-02
Also published as: WO1993014837A1; US5556122A; FR2686798A1; DE69208895D1; EP0624113B1; FR2686798B1; ATE134894T1; JPH07506980A; DE69208895T2

Abstract

L'invention concerne un dispositif visant à modifier la répartition de pression d'un ski, tel que notamment un ski alpin sur sa surface de glisse. Le ski est équipé d'au moins un élément de fixation (3) destiné à retenir une chaussure dans la zone centrale du patin, et d'au moins un élément d'appui (25) sur lequel repose la semelle de chaussure. Le ski comprend par ailleurs une embase inférieure (4), et au-dessus de l'embase, une lame de raidissement dont les deux extrémités sont liées solidairement à l'embase en avant et en arrière de la zone du patin. Le dispositif comprend par ailleurs un organe palpeur (25) en contact avec la semelle de chaussure, mobile selon une direction verticale. Il comprend par ailleurs des moyens de liaison (35) entre l'organe palpeur et la lame de raidissement (5) pour transmettre à la lame, sous la forme d'au moins une force orientée selon la direction horizontale et longitudinale en direction de l'une et/ou l'autre de ses extrémités, une partie au moins de la poussée verticale de la chaussure vers le bas captée par l'organe palpeur (25). L'invention concerne également un ski équipé du dispositif.The invention relates to a device aimed at modifying the pressure distribution of a ski, such as in particular an alpine ski on its sliding surface. The ski is equipped with at least one binding element (3) intended to retain a shoe in the central zone of the skate, and with at least one support element (25) on which the sole of the shoe rests. The ski also comprises a lower base (4), and above the base, a stiffening blade whose two ends are integrally connected to the base in front and behind the skate area. The device also comprises a feeler member (25) in contact with the shoe sole, movable in a vertical direction. It also comprises connecting means (35) between the feeler member and the stiffening blade (5) for transmitting to the blade, in the form of at least one force oriented in the horizontal and longitudinal direction in the direction of the one and/or the other of its ends, at least part of the vertical thrust of the shoe downwards picked up by the feeler member (25). The invention also relates to a ski equipped with the device.

Description

DEVICE FOR CHANGING THE DISTRIBUTION OF A SKI ON ITS SLIDING SURFACE

The invention relates to a device for distributing the pressure of a ski, such as in particular an alpine ski, over its sliding surface.

The invention also relates to a set of front and rear alpine ski binding elements, as well as an alpine ski, equipped with such a device.

The skis which are used for the practice of alpine skiing consist of relatively long boards, on which the skier's shoes are retained by front and rear fastening elements. The boot and the binding elements are located approximately in the middle region of the ski, which is commonly called the skate. The skis have in themselves, at rest, a natural camber, by which the skate is raised naturally relative to the front end of the ski, or tip, and the rear end of the ski, or heel. In addition, the skis have flexibility, which is due to their internal structure. When skiing, I ski deforms elastically in response to the various stresses to which it is subjected on the part of the skier, but also on the part of the terrain on which it slides.

The main stress to which the ski is subjected is constituted by the weight of the skier, and by the reaction to which the sliding surface subjects the ski.

The ski is also stressed by the binding elements. It is indeed known that the fastening elements pinch the shoe in a longitudinal direction. The reaction to this pinching action is transmitted by the binding elements to the ski. This reaction, however, has a different nature depending on the method of assembling the rear binding element to the ski. Indeed, some rear binding elements are assembled directly to the ski, while others are assembled to the front binding element by an inextensible link, such as a metal blade which extends under the boot.

Skiing is also influenced by the position of the skier over his boots, depending on whether he carries his weight forward or backward.

It is known that the behavior of the ski on snow can be modified, in particular its ease of initiation when cornering, its quality of driving when cornering or in a straight line, by influencing the camber of the ski, or even by playing on the longitudinal distribution of the ski pressure on the snow. By playing on this pressure distribution, it is known that one can make the ski more or less pivoting or more or less guiding, that is to say that one can promote its ability to turn easily, and to have great driving stability. For skis which are currently on the market, the pressure distribution of the ski on the snow is mainly determined by the internal structure of the ski, and by the method of assembly of the binding elements to the ski, that is to say with or without connecting blade between the front and rear elements. The pressure distribution can also be influenced by the intensity of thrust given to the recoil springs which determines the toe-in of the shoe between its fastening elements.

There are devices with attached parts which make it possible to modify the pressure distribution of the ski on snow. Thus, European patent application No. 183,586 describes a blade of material elastic spring blade type attached above the ski, between the binding elements and the ski. This blade has, at its front and rear ends, sliders through which vertically passes part of the forces to which the ski is subjected. This device however has the disadvantage of having modest performance for a large size. It is suitable for the case where both feet of the skier are in support for the same ski, to avoid that the whole weight of the skier is concentrated in the skate area. On the other hand, it is ill-suited in the case of a pair of traditional skis.

Also known, according to European patent application No. 409,749, a device consisting of a raised plate relative to the upper surface of the ski, held between two longitudinal stops. Elastic damping means are interposed between the plate and the stops, and the preload exerted on these elastic means is adjustable. The fasteners are mounted on the plate. This device gives good results, but its drawback is that the fastening elements are integral with the added plate and not with the ski itself. Other devices of the same type are described, for example, in US Pat. No. 2,560,693, and German Patent No. 2,259,375.

For these devices, it should be noted that the influence they exert on the flexion of the ski is of the static type, that is to say that it does not take into account the position of the skier on his skis during sliding.

One of the aims of the invention is to propose a device which makes it possible to modify, dynamically, the pressure distribution of a ski on its sliding surface, that is to say which takes account, during the glide, the position of the skier on his skis, and the vertical pushing effort due to the skier on his skis.

Another object of the present invention is to provide a device which also gives the shoe a suspension effect during gliding.

Another object of the invention is to propose a device which makes it possible to compensate for momentary increases in the pressure that a part of the ski exerts on snow, by transferring this additional pressure to another part of the ski.

Another object of the invention is to provide a device which also has damping qualities at the ends of the ski for vertical vibrations.

Other objects and advantages of the invention will emerge during the description which follows, this description being however given by way of indication, and not limitation.

The device according to the invention aims to modify the pressure distribution of a ski such as in particular an alpine ski on its sliding surface. The ski is equipped with at least one fastening element intended to retain a boot bearing on the ski in its central area of the skate, and at least one bearing element on which the shoe sole rests. Said ski also comprises a lower base, the front end of which is raised to form the tip, and a stiffening blade which extends freely above the base in its central part, and the two ends of which are linked to the base in front and behind the skate area.

The device according to the invention is characterized in that it also comprises: a feeler member in contact with the shoe sole, capable of sensing the vertical stresses of at least part of the shoe sole,

- connecting means between the feeler member and the stiffening blade for transmitting to the stiffening blade, in the form of at least one force oriented in the horizontal and longitudinal direction of the blade in the direction of at least one from its ends, at least part of the vertical downward thrust of the shoe captured by the feeler member.

The invention will be better understood by referring to the description below, as well as to the accompanying drawings which form an integral part thereof.

Figure 1 is a general side view of a ski equipped with front and rear fixing elements, e of a device according to a non-limiting implementation of the invention.

FIG. 2 is a top view of the ski shown in FIG. 1.

Figure 3 shows, in side view and in partial section, the ski of Figure 1 in the skate area.

FIG. 4 represents, in side view, and in partial section, the front part of the ski of FIG. 1.

FIG. 5 is a top view, in partial section, through a horizontal plane of the device represented in FIG. 4.

Figure 6 shows in perspective the base which supports the rear fixing element.

Figure 7 is an exploded perspective view at the probe and connecting means which are located under the probe.

Figure 8 is a side view in partial section at the rear fastening element, in its rest position.

Figure 9 is a view similar to Figure 8, the probe being biased vertically downwards.

Figure 10 shows, in side view, and in partial section, the two parts of the front batten in their rest position.

Figure 11 shows these two parts in a working position.

Figure 12 is a top view of these two parts in the working position.

Figure 13 illustrates an alternative embodiment of the device shown in the previous figure.

FIG. 14 is a partial exploded perspective view at the level of the probe and of the connection means under the probe for the device represented in FIG. 13.

Figures 15 and 16 illustrate an alternative embodiment of the previous embodiment.

Figures 17 to 19 illustrate alternative embodiments of the connecting means between the probe and the stiffeners.

In Figure 1, there is shown, to illustrate the invention, a ski 1 which is equipped in particular with a front fixing element 2, and a rear fixing element 3. These two fixing elements 2 e 3 are intended to retain the front and rear ends of a boot on the ski. The ski 1 is composed of two elements, a lower base 4, and an upper stiffening blade 5 The lower base 4 has an elongated shape, and it is it which is in contact with the snow. So front end 6 is raised to form the ski tip. Its rear end 7 constitutes the talo ski. The fastening elements 2 and 3 are secured to the base in its central zone 8, which is also called the shoe.

The stiffening blade 5 also has an elongated shape, and it extends above the base 4. According to FIG. 2, the width of the stiffening blade 5 is constant and less than that of the base 4. This is not limiting, and the stiffening blade 5 could have a variable width over its length. The thickness of the stiffening blade 5 can also be variable over the length of this blade, and in the figures, the thickness of the stiffening blade 5 is reduced in the area of the shoe. This is also not limiting.

The stiffening blade is made of any suitable material capable of transmitting a compression stress over its length. Preferably, the material of the blade is chosen so that the blade also has elasticity in bending in a vertical plane. For example, it is made of composite material possibly loaded with fibers.

The stiffening blade 5 extends above the base 4, from an area which is located in the front part of the ski, that is to say between the tip 6 and the shoe 8, up to a zone located in the rear part of the ski, that is to say between the heel 7 and the shoe 8. The stiffening blade 5 extends freely above the base in its central zone, and it is secured to the base 4 at its ends.

Referring to Figure 1, the stiffening blade 5 is secured, at its front end 10 and its rear end 12, to the upper surface of the base 4, these areas being located approximately at the front quarter and the rear quarter of the ski.

The ends of the blade 5 are secured to the base 4 by any suitable means, for example by screwing, gluing or welding. They can also be secured by end caps linked to the base against which they abut. Also, a layer of material having damping characteristics can be interposed between the ends of the stiffening blade and the upper surface of the base.

The front 2 and rear 3 fastening elements are integrally connected to the base 4 of the ski.

Figures 3 to 5 show that the front fastening element 2 is mounted on a base plate 13, which has in cross section a shape of jumper. This base plate 13 overlaps the stiffening blade 5, it rests on the upper surface of the base 4 by its lateral edges. The base plate 13 has, in its lower part, a longitudinal recess 17 inside which the stiffening blade 5 can slide freely in a longitudinal direction.

According to the illustrated embodiment, screws 18 secure the front fixing element 2 and the base plate 13 to the base. Any other suitable means, however, may also be suitable.

Figures 3 and 6 also show that the rear binding element 3 is mounted on the ski by means of a base plate 14 which is secured to the base 4 by any appropriate means, and in the example illustrated, by screws 20 located on the lateral edges of the base plate. Like the front base plate, the rear base plate 14 has a longitudinal recess 21 inside which the stiffening blade 5 is engaged in a longitudinal direction, and can slide freely. In the embodiment illustrated in FIG. 6, the element 21 is closed, in its upper part, only on the rear by a transverse strip 22 which connects the two lateral edges of the base 14.

It should be emphasized that the base plates 13 and 14 provide the connection between the fastening elements 2 and 3 and the base 4 of the ski, but also their role is to vertically retain the stiffening lam 4 to avoid buckling, and therefore to keep it close to the upper surface of the base.

Also, it should be noted that the base plates 13 and 14 are integral with the base 4, and no of the blade 5. The support plates associated with the fastening elements 2 and 3, on which the shoe rests, and the The binding elements themselves which retain the boot are therefore also connected to the base of the ski. Good driving qualities of the ski are thus retained because the forces between the base and the boot pass directly without passing through the blade 5.

When skiing, the stiffening blade 5 influences the bending of the base 4 in different ways. First of all, the stiffening blade 5, by its front part and its rear part, brings back, in the area of the shoe, the bending stresses of the front end o the rear end of the base. In other words, if the ski is subjected to upward flexion in its area of the tip, the front part of the stiffening blade 5 brings back, in the area of the skate, this flexion request, which can result in the form of a longitudinal sliding of the blade relative to the low amplitude base or of a compression stress brought back by the blade. It is the same for the heel.

In parallel, the blade 5 can generate bending stresses on the front end or the rear end of the ski. For example, a longitudinal forward thrust, exerted on the front part of the blade 5, is transmitted to the base 4, in its front region, in the form of a bending moment which tends to cause it to plunge towards the snow the front end of the ski. It is the same for a longitudinal rearward thrust which would be exerted in the rear part of the stiffening blade 5 this thrust would generate a bending moment of the rear end of the ski which would tend to plunge this end towards the snow. The bending moment is exerted mainly on the ski at the ends 10 and 12 of the blade which are integral with the base 4.

In the event that the stiffening blade 5 behaves in a longitudinal direction comm as a one-piece assembly, a bending stress of the base, picked up at one end of the ski, will be transmitted to the other end in the form of a bending moment. Thus, an upward bending stress on the front part of the ski generates a downward bending moment on the rear part. Conversely, an upward bias on the rear part generates a momentary downward bending of the spatula by reaction. These different stresses take place during the glide, o either because of the relief that the ski meets on its way, or because of the position of the skier on his skis. A bending stress on one end of the ski is most often accompanied by a local increase in the pressure exerted by the ski on the snow at this end. This local increase in pressure is transferred by the blade 5 to the other end of the ski which it tends plunge into the snow. This increases the grip on the snow of the part of the ski which is not subjected to flexion, which rebalances the pressure distribution of the ski on the snow.

In the case where the stiffening blade 5 is made up of two parts which do not constitute a one-piece assembly in a longitudinal direction, the stresses picked up by each of the parts are brought back into the area of the skid; conversely, it is possible to generate, from the skate area, longitudinal thrust forces on the front or rear part of the blade, which in turn generate bending moments of the front end or the end rear of the base.

Furthermore, the front and rear parts of the stiffening blade 5 respectively have elastic flexibility in the vertical and longitudinal plane defined by the ski. They therefore also play, on the front and rear parts of the base 4, a damping role for vertical vibrations.

The device which is the subject of the present invention also has a feeler member, which is in connection with the shoe sole, and which is capable of sensing at least the vertical downward stresses exerted on it by the sole.

The device also comprises connecting means between the feeler member and the stiffening blade 5, which transform the vertical stresses of the shoe into one or two longitudinal thrust forces at the stiffening blade 5, oriented towards the front end and / or rear end thereof.

Thus, the feeler member, the connecting means and the stiffening blade 5 are capable of generating bending moments of the front end and / or the rear end of the ski from the vertical stresses that the boot exerts on the feeler organ. This is superimposed on the front-rear transmission function which has been described previously. Therefore, a bending moment can be generated at one end of the ski, or by a bending stress which occurs at the other end, or by a vertical stress on the boot.

According to the embodiment illustrated in the figures, the feeler member is constituted by the support plate 25, which is associated with the rear fastening element 3, and on which the rear end of the shoe sole rests.

In a known manner, the body of the rear fastening element 3 is slidably mounted along a slide 26, and the support plate 25, which constitutes the feeler member, extends the slide 26 which is also connected to the base plate 14, in its rear part, by a horizontal and transverse articulation axis 28. The base plate 14 in fact has two longitudinal and vertical wings 29 and 30, between which the stiffening blade 5 passes, and between which is located the base plate 14. These wings carry the axis 28 in their rear part. The slide 26, and therefore the feeler member 25, have a rotational movement around the axis 28 in the vertical and longitudinal median plane defined by the ski. On the other hand, the axis 28 does not allow a rolling movement of the probe 25.

The vertical stresses of the boot are absorbed by the vertical movement of the feeler 25 around the axis 28. The transverse roll stresses are on the other hand transmitted directly to the base 4 of the ski.

The axis 28 is not limiting, and any other means of assembling the fixing element 3 which ensures vertical movement of the feeler member 25 may be suitable. Preferably, the rotational movement of the slide 26 is limited downwards and upwards. The limiting means are represented in the figures by a horizontal and transverse pin 32, located in the front part of the slide 26. The ends of the pin 32 circulate in vertically oriented slots 33 and 34 which are carried respectively by the wings 29 and 30 of the base plate 14. The rotational movement is limited by the abutment of the ends of the pin 32 in the upper part or the lower part of the slots 33 and 34.

Optionally, a spring or a damping block can be placed between the slide 26 and the base plate 14 to bias the slide upwards and to counteract or dampen its downward movement.

The connecting means which connect the feeler member 25 to the connecting blade 5 are notably visible in FIG. 7. According to this figure, the stiffening blade 5 is in two parts, that is to say a front slat 37 and a rear batten 38 which meet at the level of the feeler member 25.

The connecting means comprise a rocker 35 which, seen from the side, has approximately an L shape with a vertical branch 35a and a horizontal branch 35b. The rocker 35 is suspended around an axis 36 which is located in the upper part of its vertical branch 35a. The axis 36 is itself carried, at its ends, by the wings 29 and 30 of the base plate 14, at the level of two oblong holes 39 and 40 which are oriented in a horizontal and longitudinal direction. Also, the pin 36 passes through the front end of the rear slat 38 which preferably has at this level a piece of end piece 42. The pin 36 thus ensures the connection between the rear slat and the connecting means.

An axis 43 is also located in the central part of the rocker 35, that is to say below the level of the axis 36, at the junction of the vertical and horizontal branches. The axis 43 provides the articulation connection between the rocker 35 and the rear end of the front batten 37.

The rocker 35 also includes, at the free end of its horizontal branch 35b, a bearing zone 45 on which the feeler member 25 comes to rest in a vertical direction by means of the slide 26. In the illustrated example, the support zone 45 is in two parts which are situated on either side of the front end 42 of the rear batten 38. The slide comes to rest, in a vertical direction, on the support zones 45 by two lateral pads 46.

The assembly which has just been described is dimensioned in such a way that the tilting of the slide 26 can occur, in a vertical and longitudinal plane around the axis 28, over an amplitude defined by the axis 32 and the lights. 33 and 34 that the ends of the axis pass through. During this movement, the lateral pads 46 of the slide 26 are in abutment on the zones 45 of the rocker 35, and cause its rotation about its axis 36 which is carried by the oblong holes 39 and 40. The rotational movement of the rocker 35, resulting from a downward movement of the feeler member 25, causes a relative distance of the front and rear slats 37 and 38 in a longitudinal direction. Conversely, the relative approximation of the slats 35 and 38 corresponds to the rotation of the rocker in the opposite direction, and to the ascent of the feeler member 25.

Preferably, at rest, that is to say in the normal ski position, the slats transmit to the rocker a compression preload which tends to keep the body member 25 in the high position. Abutment means further limit the relative approximation of the slats 37 and 38, that is to say ensure a securing of the slats for a longitudinal movement in the direction of approximation.

These means are constituted in the embodiment illustrated by the ends of the pin 32 and the slots 33 and 34 of the rear fixing element.

Indeed, when the pin 32 is in upward abutment in the slots 33 and 34, the rotational movement of the rocker 35, in the direction of a relative approximation of the slats 37 and 38, is blocked. On the other hand, the assembly of the two slats 37 and 38 and the rocker 35 can still translate in a longitudinal direction because the axis 36 of the rocker can move in the oblong holes 39 and 40. The two slats become integral one on the other for any longitudinal request for relative approximation.

This is not limiting, other means could be suitable, for example, the ends of the slats 37 and 38 could be provided to come into abutment against one another by direct contact.

The axis 36, around which the rocker 35 is suspended, is located at a sufficient height relative to the upper surface of the base 4, so that the rotation of the rocker 35 and the translational movements of the front and rear slats 37 and 38 can be done without interference with the upper surface of the base 4. In particular, the ends of the slats 35 and 38 are slightly raised relative to the base 4 at this level.

Furthermore, the assembly formed by the front batten 37, the rocker 35 and the rear batten 38 can translate in a longitudinal direction forwards or backwards. This translation is permitted since the axis 36 is carried by the wings of the base 4, at the level of oblong holes 39 and 40.

Thus, the translation of one slat in the direction of approximation of the other can cause either the rotation of the rocker 35 about its axis 36, or the longitudinal translation of the rocker 35 and the other slat, by translation of the axis 36 in the oblong holes 39 and 40, or a combination of these two movements.

Figures 8 and 9 illustrate the operation of the device which has just been described.

In FIG. 8, the rear end of the shoe does not exert vertical downward bias on the feeler 25, or rather the vertical force that the shoe exerts on the feeler 25 is less than the vertical prestress upward, to which the device subjects the probe. The axis 32 is in abutment upwards in the slots 33 and 34 of the base plate 14. The axis 36, around which the rocker 35 is suspended, is located approximately in the central part of the oblong holes 39 and 40 presented by base plate 14.

The slats 37 and 38 are integral with each other for a request for relative approximation.

In this configuration, as has been said previously, if the front end of the ski is subjected to a bending stress, the whole assembly consisting of the front batten 37, the rocker 35, and the rear batten 38 translates towards the 'back. This has the effect of generating, at the rear end of the ski, a bending moment tending to plunge this rear end towards the snow. The reverse is also true, i.e. a bending stress on the rear end of the ski tends to plunge the front end forward. During such forward or rearward translation, the rocker 35 moves in a longitudinal direction under the pads 46.

In FIG. 9, the shoe exerts, on the probe 25, an additional vertical downward force shown diagrammatically by the arrow P. This force causes the downward movement of the probe 25 and of the slide 26, the axis 32 circulates in the lights 33 and 34. The rocker 35 is rotated around the axis 36, which causes a relative distance of the front and rear slats 37 and 38, which has been translated in the figures by thrusts P1 oriented forward and P2 oriented towards the rear These thrusts P1 and P2 respectively generate bending moments of the front end and of the rear end of the ski.

In this position of the system, as before, a bending stress on the front or rear end of the ski is transmitted by the slats 37 and 38 and the rocker 35 at the other end of the ski, in the form of a moment of bending which is added to the bending moment generated by the push P.

Such stress can also cause the rocker to rotate in the direction of bringing the slats 37 and 38 together, and thereby raise the probe 25.

Thus, the increase in the pressure of one end of the ski on the snow, due to the relief or to the position of the skier, is absorbed and returned to the other end of the ski which is subjected to an additional bending moment tending to plunge this end towards the snow. In the case where the skier modifies his position of equilibrium on his skis, and in particular, moves back the poi of application of the vertical stress that the shoe exerts on his supports, the thrust increases, which generates a additional bending moment on the front end and the rear end of the ski.

When the skier returns to a normal position, that is to say that the stress P decreases, the base 4 and the slats 37 and 38 return the rocker 35 to its initial position, which pushes the probe 2 and the shoe back into their high position.

Depending on the intensity of the push P exerted by the shoe, the feeler descends and rises. This achieves an elastic suspension of the shoe in a vertical direction. Furthermore, the feeler 25 does not react to purely lateral stresses given its articulation around the axis 2. These stresses pass directly between the shoe and the base 4.

Preferably, the stiffening blade 5 has, at rest, a compression preload so as to be able to bring the probe 25 upwards when the skier is in normal support on his sk. According to a preferred embodiment, this preload can be established or else canceled depending on the presence or absence of the shoe. Such a construction is illustrated in FIG. 10 to 12. According to this construction, the front batten 37 has, in its rear part, two elements articulated in the manner of a toggle 48 and 49 which extend along a longitudinal direction of the 'base 4. The two elements 48 and 49 are respectively articulated, at their free end, at the front batten 37, at an axis 50, and at the rocker 35, at the axis 43 previously described. In addition, the two elements 48 and 49 are articulated together around a horizontal and transverse axis 51. In one of the two elements, the element 49 in the case of the figures the axis 51 is mounted in a slot 52 oriented in the longitudinal direction of the element. The axis 51 can therefore slide along this lumen, and it is returned elastically towards the end of the element by at least one spring 53.

In the absence of a shoe, the toggle formed by the elements 48 and 49 can be opened, which eliminates any pretension in the stiffening blade 5. This is illustrated in FIG. 10. It is then possible for the feeler 25 to be placed of itself in the low position if no own elastic return means keeps it in its high position.

FIGS. 11 and 12 illustrate the case where the elements 48 and 49 of the toggle joint are flattened, which displaces the axis 51 in the slot 52 against the return force of the spring 53. The return spring then generates a compression preload in the stiffening blade 5.

To prevent the spring 53 from compressing additionally during skiing, a stop is provided for coupling, in an integral manner, in a longitudinal direction, the elements 48 and 49 of the toggle joint. In the case of the figures, this stop is constituted by a micrometric screw 55, which is mounted on a cross member of the element 49, and which is brought into abutment against a longitudinal tongue 56 of the element 48. Thus, all the stresses or all the longitudinal forces will be transmitted directly from one element of the toggle joint to the other, without stressing the spring 53.

When the boot is again absent, the screw 55 is unscrewed, then the toggle can be broken to release the ski from the preload.

Figures 13 and 14 illustrate an alternative embodiment. According to this variant, the stiffening blade 5 has a front slat 67 and a rear slat 68, which are joined together at a rocker 65 similar to the previous rocker 35. The slats 67 and 68 and the rocker 65 are hinged together around a same axis 63 which is located in the central part of the rocker. Thus, the two slats 67 and 68 are integral with each other for all the longitudinal movements forwards or backwards. The rocker 65 is, for its part, connected to the base plate 14 of the rear fixing element, at the level of an axis 66, the ends of which are carried by orifices 69 and 70 of the base 14. Unlike the previous case where the rocker 35 could have a rotational movement and a translational movement; in the present case, the rocker 65 has only one possible movement of rotation about its axis 66.

In the case of this variant, the vertical downward stresses of the shoe on the feeler 25 are transmitted to the stiffening blade 5, in the form of a forward-facing thrust force, which is exerted as well on the front batten than the rear batten.

At the same time, a bending stress on the front end of the ski can be transmitted to the rear slat, as long as the feeler 25 is not in the top stop, that is to say where the pin 32 n is not in abutment in the slots 33 and 34 of the base plate 14. On the other hand, a bending stress from the rear end of the ski can be transmitted to the front batten 67, but it causes a displacement of the axis 63 and a collapse of the feeler member 25.

FIGS. 15 and 16 illustrate an alternative embodiment, according to which the two front and rear slats 67 and 68 are integrally coupled only for a translational movement towards the rear of the slat 67. For example, as is illustrated, the rear batten 68 is in simple support in a longitudinal direction towards the front, against a connecting piece 70. It is this piece of liaiso 70 which is connected to the rocker 65 and to the front slat 67, around the axis of articulation 63. FIG. 1 illustrates the operation of this variant in the case where the rocker 65 is rotated under the effect of a thrust P '. The front batten 67 is then driven in forward translation. Pa against, the rear slat 68 is free to follow or not this translational movement according to the flexural stress to which the rear end of the ski is subjected. In this case, the connecting means transfer only to the front end of the ski the stresses picked up by the feeler member 25. Pa against, when the feeler is in the high position, that is to say in the case of FIG. 15, a bending stress which is exerted on the rear end of the ski is transmitted to the front batten 67, from the moment when the rear batten 68 is in abutment against the connecting piece 70.

Figures 17 to 19 relate to alternative embodiments of the liaiso means described above.

According to Figure 17, the connecting means between the feeler member 25 and the stiffening blade 5 its constituted by a toggle device consisting of two levers 71 and 72, the free ends of which are respectively articulated at the end of each of the front and rear slats. The feeler 25 is in support at the level of the hinge pin 73 which is common to the two levers 71 and 72. It is understood that a push down of the feeler 25 on the toggle joint causes it to flatten, d 'o a relative distance from the two front and rear slats 88 and 89. Preferably, according to this variant the two front and rear slats 88 and 89 are in abutment against one another, in a longitudinal direction, when the knee lever is in its rest position which corresponds to the high position of probe 25. For example, the ends of the slats 88 and 89 can be equipped with stop pieces 90 and 91, which come into contact with one another, and which also carry the articulation axes to which the free ends of the levers 71 and 72 are connected.

FIG. 18 illustrates another alternative embodiment, according to which the toggle joint device is replaced by a strip 92 curved upwards, the ends of which are connected to each of the front and rear slats. The probe 25 is in abutment against the curved blade 92 in the central part thereof. It is understood that a vertical downward bias, exerted by the feeler on the blade 92 causes a flattening of the latter, that is to say a relative distance of the front and rear slats 8 and 89.

Figure 19 shows another alternative embodiment, in the case where the stiffening blade consists of a single piece. In this case, the stiffening blade carries a bearing 9 to which is articulated an oblique lever 95 oriented from top to bottom, from rear to front. The free end of the lever 95 is in abutment against a longitudinal stop 96 which the slide presents under the feeler 25. It is understood that a downward movement of the feeler 25 tends to pivot the lever 95 towards the ski, which forces the bearing 93 to translate towards the front of the ski.

It goes without saying that the invention is not limited to the various embodiments and to the variants which have been described. Other embodiments and variants could indeed be adopted by the skilled person, without departing from the scope of the invention. In addition, the feeler member 25 could be associated with the front fixing element, or else be independent of one or the other of the fixing elements. The feeler member could also be independent of the front and rear support plates on which the shoe rests. For example, it could be placed at the central part of the shoe between its front and rear supports.

In particular, the toggle joint which allows the blade 5 to be prestressed and the variants of the connecting means could be fitted to any of the embodiments which have been described.

Claims

1- Device aimed at modifying the pressure distribution of a ski such as in particular an alpine ski on its sliding surface, the ski being equipped with at least one fastening element (2,3) intended to retain a boot in its central zone of the shoe (8), and of at least one support element on which the shoe sole rests, said ski also comprising a lower base (4) whose front end (6) is raised to form the spatula, and a stiffening blade (5) which extends freely above the base

(4) in its central part, and the two ends (10,12) of which are linked to the base (4) in front and behind the area of the shoe (8), characterized in that it comprises elsewhere :

a feeler member (25) in connection with the shoe sole, capable of picking up a vertical thrust (P) of the shoe on the base,

- connecting means (35,36,43,65,66,63) between the feeler member (25) and the stiffening blade

(5) to transmit to the stiffening blade, in the form of at least one force oriented in the horizontal and longitudinal direction of the blade towards at least one of its ends, at least part of the vertical thrust (P) of the shoe downwards picked up by the feeler member.

2- Device according to claim 1, characterized in that the feeler member (25) is movable in a vertical direction, and that its vertical movement is limited at least upwards by a stop (32,33,34).

3- Device according to claim 1, characterized in that the stiffening blade (5) is composed of two front and rear slats (37,38) located in the extension of one another, which are also movable one relative to the other in a longitudinal direction.

4- Device according to claim 3, characterized in that the connecting means between the feeler member and the stiffening blade comprise a rocker (35) with two branches which has two axes of horizontal and transverse articulation (36,43 ) for the end of each of the slats (37, 38), and which moreover has a bearing zone (45) on which the feeler (25) exerts the vertical thrust (P) transmitted by the shoe, in such a way that a push (P) of the vertical shoe down causes rotation of the rocker in the direction of a relative distance of the two slats (37,38) of the blade (5).

5- Device according to claim 4, characterized in that the rocker (35) is suspended around a hinge pin (36) whose ends are carried by an element (14) integral with the base (4) at oblong orifices (39,40) oriented in a longitudinal direction, so that the rocker (35) can translate in a longitudinal direction.

6- Device according to claim 5, characterized in that the axis (36), to which the rocker (35) is suspended, is located in the upper part of the rocker, and that this axis (36) is also the axis articulation of the rear batten (38) to the rocker (35).

7- Device according to claim 3, characterized in that the connecting means between the feeler member and the stiffening blade comprise a toggle device oriented in a direction parallel to that of the stiffening blade, consisting of two levers ( 71, 72) articulated together around a longitudinal and transverse axis (73), the end of a lever being connected to a stop integral with one of the slats of the stiffening blade, the end of the other lever being connected to the other slat, and the feeler (25) coming to bear on the central part of the toggle joint device.

8- Device according to claim 3, characterized in that the connecting means comprise a strip (92) oriented in a longitudinal direction, the central portion is curved upward, one end of which is integrally connected to one of the slats of the blade, the other end of which is integrally connected to the other slat, and the central convex part of which receives the downward vertical forces picked up by the feeler (25).

9- Device according to claim 3, characterized in that the feeler member (25) rests in simple support on the part of the connecting means (35,71, 72,73,92) which transmits to the two slats (37, 38) the thrust (P) picked up by the feeler member (25).

10- Device according to claim 6, characterized in that in the absence of vertical thrust of the shoe on the probe (25), the two slats (37,38) of the blade are in longitudinal support one against the other at their adjacent end so as to transmit, to one of the ends of the blade (5), the stresses of the ski on bending perceived by the other end.

11- Device according to claim 1, characterized in that the stiffening blade (5) behaves in a longitudinal direction as a unitary assembly and that the connecting means (65,66,63) transform the vertical thrust of the shoe in a longitudinal force oriented towards a single end of the stiffening blade.

12- Device according to claim 11, characterized in that the connecting means between the feeler member and the stiffening blade comprise a rocker (65) with two branches, articulated around a horizontal and transverse axis, (66) carried by an element (14) integrally connected to the base (4), moreover having a hinge pin (63) with the stiffening blade (5) and a bearing zone on which the probe transmits the vertical thrust of the shoe, so that a downward vertical force exerted on the feeler is transmitted by the rocker to the stiffening blade in the form of a force oriented in the longitudinal direction of the blade oriented forward.

13- Device according to claim 11, characterized in that the connecting means between the feeler member (25) and the stiffening blade (5) comprise an inclined lever (95) which extends between a bearing (93) secured to the stiffening blade (5) and to a longitudinal stop (96) movable vertically with the feeler (25).

14- Device according to claim 1, characterized in that the stiffening blade (5) is composed of two front slats (67) and rear (68), that the connecting means (65) are connected to the front slat ( 67), and that the rear batten (68) is connected to the rest of the batten (5) by a simple support in a longitudinal direction forward.

15- Device according to any one of the preceding claims, characterized in that the stiffening blade (5) has a compression preloading device.

16- Device according to claim 15, characterized in that one of the slats (37) has two elements (48,49) hinged together in the manner of a toggle about a horizontal and transverse axis (51) in such a way that in the presence of the shoe, the kneepad is flattened, which generates an initial prestress in the two parts of the stiffening blade, and that in the absence of a shoe, the toggle breaks, which frees the stiffening blade from its prestress. -

17- Device according to claim 18, characterized in that the hinge pin (51) of the two elements (48,49) of the toggle is slidably mounted along one of the elements in the direction of distancing the other element against the elastic return force of at least one spring (53).

18- Device according to claim 17, characterized in that it has a play take-up means (55) which abuts, in a longitudinal direction, the two elements of the toggle when it is in the flattened position.

19- Device according to any one of the preceding claims for a ski equipped with a front binding element (2) intended to retain the front of the boot, and a rear binding element (3) intended to retain the rear of the shoe, characterized in that the feeler member (25) is the support plate associated with the rear fastening element (3), on which the rear end of the shoe sole rests.

20- Device according to claim 19 for a ski, the rear binding element (3) comprises, in addition to the boot support plate, a body mounted sliding along a slide (26), characterized by the fact that the support plate which constitutes the probe is integral with the slide (26), and that the slide (26) is articulated about a horizontal and transverse axis (28) relative to a base plate (14 ) integrally connected to the base (4) of the ski.

21- Device according to claim 20, characterized in that the base plate (14) of the rear fixing element (3) has a longitudinal recess (21) which passes through the stiffening blade (5).

22- Device according to claim 19, characterized in that the front fixing element (2) is mounted on a front base plate (13) integral with the base (4), which has a longitudinal recess (17) crossed by the stiffening blade (5).

23- Ski, in particular intended for alpine skiing, comprising a base (4) raised at the front to form the tip, and a stiffening blade (5) located above the base, and secured to that -ci at its two ends (10,12), characterized in that it further comprises a device for modifying the pressure distribution of the base on the snow according to any one of the preceding claims.