EP0627947B1 - Bearing device for a ski shoe onto a ski, and associated to a safety front stop - Google Patents

Abstract

The device is comprised of a sole bearing plate (1) susceptible of moving transversally with respect to the ski (4), along a preset trajectory, for example by pivoting about an axis (Y). The front stop (3) is connected to the bearing plate (1) through a linking member (6) which is elastically deformable. The device applies to ski equipment.

Description

The present invention relates to a device for supporting the front of a boot on a ski, which is associated with a safety front stop.

The vast majority of modern safety ski bindings include a rear heel retainer, generally known as a heel piece, and a front toe retainer, generally referred to as a toe-stop.

The heel opens to release the boot from the ski in the event of excessive efforts linked to a stress on the leg in the forward fall. The front stop releases the shoe under the effect of excessive lateral forces, linked to a fall in torsion. Some front stops also allow the tip of the shoe to escape in the event of a rear fall.

To limit friction at the front of the boot, the front part of the sole does not rest directly on the ski, but on a support plate with a low coefficient of friction, this plate generally being integrated into the plate of mounting the front stop on the ski.

The backing plate has a lining in anti-friction synthetic material, generally in P.T.F.E. (Polytetrafluoroethylene) or a material with similar properties.

To further limit friction, it has also been proposed to make the support plate mobile. This is guided to move in a general transverse direction relative to the ski, so as to follow a trajectory identical to that of the sole, or close to the latter. Appropriate elastic means allow the backing plate to be returned to its normal position, centered on the ski, as soon as the lateral stress exerted by the boot has ceased.

Devices of this kind are described for example in the German patent application 2 333 166 and in the French patent application No. 89 12761 (publication No. 2 652 508).

If this kind of device is satisfactory under normal ski conditions, it can cause certain problems under circumstances particular. Thus for example, when the skier is in rear imbalance, which is the case in particular in the event of the start of a rear fall, or in conditions of skiing in fresh snow, it may happen that the underside of the sole deviates from the backing plate. This is particularly true when the front stop has a rear fall compensation system or an ability to trigger a rear fall, the jaw of the front stop can then accompany the lifting of the tip of the shoe.

If, at this moment, there also appears a torsional stress which causes the opening of the jaw of the front stop, on one side or the other, the boot will be off-center with respect to the ski while the plate support will remain in the axis of the ski. Assuming that the rear imbalance then ceases, while the lateral stress continues, the sole will come back to bear with a lateral offset on the support plate. There is then a problem when refocusing the boot on the ski, the boot then tending to offset the support plate by moving it to the other side.

In another known embodiment, the sole support plate is carried by a pedal which is integral with the front stop.

An embodiment of this type is described in particular in document FR-A-2 449 459. In such a device, the trajectory of the support plate is therefore dependent on that of the front-stop jaw. Thus, if we are dealing with a front stop with pivoting jaw, the support plate will pivot around the same axis as the jaw, that is to say about an axis located in front of the shoe. This is not satisfactory because, in the vast majority of torsional falls, the shoe rotates around an (virtual) axis located between the middle part and the heel of the shoe, for example around an axis corresponding approximately. to that of the shin.

During the torsional release, there is therefore a relative sliding of the sole relative to the support plate, which is due to the difference in their trajectory. To best limit this relative sliding, it has been proposed in the device which is the subject of the aforementioned document, to articulate the support plate on the pedal. In addition, in the mode embodiment of Figures 9 and 10, the support plate is connected to the front stop by means of an elastically deformable connecting member such as a corrugated elastic wire.

These provisions only slightly reduce the disadvantages which have just been mentioned. In addition, if the elastic member is deformed, for example following an impact, the support plate can come to occupy at rest any position, in particular being detached from the ski, which entails a risk of degradation of its sliding surface on the ski.

The German patent application published under number 34 21 499 describes a set of fasteners comprising a front fastening with pivoting body, and a rear fastening mounted on a plate articulated in rotation around a vertical pivot. The shoe rests on the plate on the front and on the back. In addition, the front end of the plate is connected to an arm connected to the body of the front attachment, so that the rotations of the front attachment and of the plate carrying the rear attachment are controlled by one another.

This construction is however complex because of the connection between the front and rear attachments. In addition, if the connection becomes blocked, for example due to the glass, the front attachment can no longer pivot to the side. Therefore, lateral release of the shoe by the front binding poses a reliability problem.

The present invention aims to solve these various problems by proposing a device for supporting a boot on a ski, which is associated with a safety front stop, and in which the sole support plate is movable and can follow a well-defined trajectory, which can be chosen to be identical or very close to that of the sole, the movement of this movable plate being nevertheless governed or controlled by the displacement of the front-stop jaw, but the movable plate nevertheless being able to move freely in an elastic manner and over a short stroke relative to an average position which is imposed on it by the trigger movement of the front stop.

This objective is achieved in accordance with the invention thanks to the fact that this device comprises guide means ensuring a movement along a predetermined trajectory, generally transverse to the ski, of a movable sole support plate, the device comprising a link which connects this movable plate to the front stop so that the opening of this latter causes or authorizes the transverse displacement of the movable plate, the connecting member being elastically deformable.

In one possible embodiment of the invention, this connecting member is a flexible tongue.

Advantageously, the movable plate can pivot laterally around an axis centered on the ski and located under the boot.

In one embodiment of the invention, the means which provide the pivoting guide for the movable plate consist of a fixed cylindrical stud which engages in a hole in the support plate.

In another embodiment, these means consist of a fixed rib, with an arcuate outline, which engages in a complementary groove made in the plate.

The device can advantageously be applied to a front stop of the type with pivoting body carrying the shoe retaining jaws; in this case, according to a preferred embodiment of the invention, this pivoting body is integral with a substantially vertical rod, centered on the ski, and fixed to the elastic connecting member.

In a particularly simple and advantageous embodiment, this rod engages in a lumen formed in one of the ends of the flexible tongue, the latter being secured by its other end to the movable plate.

This arrangement allows a good drive of the support plate by the pivoting body during its release movement, despite the divergence of the two trajectories, the rod being able to slide in the lumen of the flexible tongue. This training remains possible even if the retaining jaws are raised.

The invention is also applicable to other types of front stops.

It can thus be applied to a front stop comprising a pair of jaws articulated on a cross member which is movable transversely; in this case it is this cross which can advantageously be connected to the elastic connecting member.

Another type of front stop comprises a pair of independent bent jaws which are articulated on a fixed body and each act on a central slide resiliently stressed. In this case, it is possible to provide the support plate with a cam path cooperating with a follower member, the latter then being connected to the slide by the elastic connecting member.

The invention is defined in claim 1. Particular embodiments are given in dependent claims 2 to 9.

Other characteristics and advantages of the invention will appear from the description and the accompanying drawings which show preferred embodiments.

• la figure 1 est une vue éclatée, en perspective, d'un premier mode de réalisation de l'invention appliquée a une butée-avant a corps pivotant ;
• la figure 2 est une vue de dessous de la plaque d'appui mobile équipant ce dispositif ;
• la figure 3 est une section longitudinale de la plaque d'appui de la figure 2, le plan de section étant référencé III-III à la figure 2 ;
• les figures 4, 5 et 5A sont des vues de dessus schématiques, avec arrachement, destinées à illustrer le fonctionnement du dispositif ;
• la figure 5B est une vue de côté schématique, et à petite échelle, de la butée-avant lorsqu'elle est sollicitée en chute arrière ;
• la figure 6 est une vue de dessus très schématique montrant une variante des moyens de guidage de la plaque d'appui mobile ;
• les figures 7 et 8 sont des vues schématiques correspondant à deux autres modes de réalisation possibles de l'invention appliqués à des butées-avant de type différent ;
• la figure 8A est une vue partielle correspondant à la figure 8 qui illustre la possibilité de désaxage de la plaque d'appui par rapport à sa position moyenne.

In these drawings:

• Figure 1 is an exploded perspective view of a first embodiment of the invention applied to a front stop with pivoting body;
• Figure 2 is a bottom view of the movable support plate fitted to this device;
• Figure 3 is a longitudinal section of the support plate of Figure 2, the section plane being referenced III-III in Figure 2;
• Figures 4, 5 and 5A are schematic top views, with parts broken away, intended to illustrate the operation of the device;
• Figure 5B is a schematic side view, and on a small scale, of the front stop when it is biased in rear fall;
• Figure 6 is a very schematic top view showing a variant of the guide means of the movable support plate;
• Figures 7 and 8 are schematic views corresponding to two other possible embodiments of the invention applied to front stops of different type;
• Figure 8A is a partial view corresponding to Figure 8 which illustrates the possibility of offsetting the support plate relative to its average position.

The device represented in FIG. 1 comprises a safety front stop 3, of a type known per se, which is carried by a base, or plate, 20 fixed to a ski 4 by means of screws 21. It is a stop with pivoting body 33 carrying lateral jaws 31, preferably adjustable in width, so as to adapt to the width of the toe of the shoe. The body 33 can pivot laterally, on one side and the other, around a vertical pivot, that is to say perpendicular to the ski, the axis of which is designated 30. This body 33 contains a mechanism safety (not shown) comprising an elastic return system, of known type.

The support plate 1 is a molded plate of mechanically resistant synthetic material, which, in a well-known manner, is provided at its upper part with a strip 10 of material with a low coefficient of friction, for example PTFE At its rear part , i.e. on the side corresponding to the back of the ski (towards the heel of the shoe) the part 11 of the support plate is pierced with a central hole 13. This is intended to engage on a cylindrical stud 25, of corresponding diameter, which forms an integral part of the fixed plate 20. In before the stud 25, the plate 20 has a flat rib 22 which has an arcuate shape, centered towards the rear of the ski. On this rib is fixed, for example glued, a lining 23 with a low coefficient of friction, for example in PTFE On the underside of the support plate 1 is provided a clearance corresponding to the rib 22, allowing the underside of the plate support to bear on the anti-friction lining 23. Thicker parts 14, 15 provided under the plate 1 are positioned respectively at the rear and at the front of the rib 22. As will be seen by the these elements do not interfere with the pivoting of the support plate 1 around the stud 25.

The plate 1 is fixed to the plate 20 by means of a screw 5. The latter has a threaded part of small diameter 51 which is screwed into a tapped hole 26 provided in the stud 25. It has a head 50 of large diameter which is housed in a cylindrical counterbore 12 bordering the hole 13 of the plate 1. This arrangement allows an articulated connection of the support plate 1 on the plate 20, with the possibility of pivoting about a vertical axis Y corresponding to the pin axis 25.

Of course, the screw 5 could be replaced by a non-removable link, in particular by a rivet.

Holes 16 provided in the front part 17 of the plate 1 allow access to the screws 21 (using a screwdriver) for fixing the assembly on the ski.

In Figure 2 there is designated by the reference 100 the underside of the support plate at its clearance between the rear elements 14 and front 15 of greater thickness. It is the zone 100 which comes to bear on the anti-friction lining 23. The front projecting element 15 has the general shape of a transverse rib. The latter carries in its central zone an elastically deformable member 6. It is a tongue 62, flat and of rectangular section. It extends longitudinally under the front part 17 of the support plate. Preferably the tongue 62 forms an integral part of the support plate, and comes from molding therewith. At its free front end, the tongue 62 has an enlarged head 61 in which is formed an elongated hole 60, or lumen, arranged longitudinally.

The material constituting the tongue 62 is such that the latter can flex elastically laterally, over a limited stroke, for example over ten degrees on either side of the longitudinal axis of the plate 1.

The body 33 of the front stop is integral with a vertical rod 32. The latter is located in the axis of the ski, behind the axis of rotation 30.

The rod 32 engages in the lumen 60.

With reference to FIGS. 4, 5 and 5A, we will now explain how the device which has just been described works.

In these figures, the tip of the ski is to the right.

In the rest position, which is the position shown in FIG. 4, the abutment body 33 is immobilized by its elastic return system (not shown) in a position centered on the ski and its longitudinal axis is referenced Xo. The support plate 1 is therefore also centered on the ski by means of the rod 32 and the connecting tongue 62. It will be noted that the lumen 60 is positioned in such a way that in this rest position the rod 32 is at the rear end of the light.

The boot (not shown) being in place on the ski, the underside of the sole comes to bear, via a smooth zone, the dimensions and location of which are standardized, on the anti-friction lining 10 .

Under normal conditions of skiing, in the absence of excessive torsional stresses, the front stop remains in its centered position in FIG. 4. Nevertheless, thanks to the flexibility of the tongue 62, the support plate 1 can, if necessary, move slightly, by pivoting around the Y axis, on either side of its average position Xo. This is particularly interesting if, despite the presence of the anti-friction plate 10, the friction appearing between the shoe and the support plate is high, for example in the case where a frozen snow pad has formed under the shoe. In this hypothesis, it is very advantageous to have this freedom of elastic movements because the static friction which thwarts the start of the movement of the boot, and which opposes, on the one hand, the movement of the boot relative to the ski, and on the other hand at the beginning of the movement for triggering the front stop - that is to say at the pivoting of the body 33 - will not be added because they will be slightly offset in time. In fact, the shoe / movable plate assembly will be able to start moving before actually requesting the jaws of the binding, this in particular because of the functional clearances and the flexibility of the shoe.

In addition, the flexibility of the tongue 62 allows the device to absorb certain vibrations which are not dangerous for safety, but which are troublesome for the comfort of the skier, without requesting the front stop 3.

Figure 5 shows the device during a lateral release, which occurs during a high stress of the shoe in torsion. In this case, the front stop body 33 pivots about the axis 30, as shown by the arrow F. The lateral displacement of the rod 32 integral with the body 33 in turn causes the lateral displacement, on the same side, of the support plate 1. The latter pivots about the axis Y as shown by the arrow G. It is important to note that the distances between the rod 32 and the axis 30 on the one hand and between the end 61 of the tongue 62 and the axis Y on the other hand, are chosen so that the travel of the backing plate corresponds exactly to that of the shoe. As also the Y axis is under the shoe, for example at the level of the arch of the foot, the trajectories also coincide satisfactorily. It follows that the support plate accompanies the sole so that the relative sliding between the underside of the sole and the lining 10 are extremely limited. Because, in addition, the movable support plate rests on the fixed base 20 by means of an anti-friction lining 23, the release of the boot is done in a particularly gentle and safe manner.

In FIG. 5, the longitudinal axis of the support plate has been designated by the reference X in an intermediate position of release. As illustrated in FIG. 5A, the support plate 1 has a certain additional freedom of movement relative to the direction X , which could be described as "average direction". In fact, thanks to the flexibility of the tongue 62, the plate 1 can pivot around the Y axis, on one side or the other of the X axis, independently of the movement of the front stop. Thus, in Figure 5A there is shown an additional pivoting, in the same direction as the initial direction of movement, of the support plate whose longitudinal axis is referenced X ' . This additional pivoting, of a few degrees, is symbolized by the arrow G ' . It causes an elastic bending of the tongue 62. Of course, a similar movement could be observed in the other direction.

This ability to move the support plate further makes it possible in particular to absorb certain vibrations and improve the comfort of the skier.

It should be noted that the support plate will follow the movement of the boot even if it is not directly biased by the latter, which is the case in particular if the front of the boot is detached from the ski. The drawbacks which have been mentioned in the preamble to the present description, and which are linked to the mobile bearing plates recalled by an independent elastic system, are therefore avoided here.

As already mentioned, the presence of a light for the engagement of the control rod 32 makes it possible to compensate for the divergence of the trajectories of the front stop and of the support plate. As seen in Figure 5B, this arrangement also allows the device to operate even if we are dealing with a front stop whose jaws can be lifted during skiing. Thus, in the example shown in FIG. 5B, the jaws of the front stop can be lifted relative to the ski, in particular in the event of stress in rear fall or in the presence of an excessive layer of snow under the sole. of the shoe. This movement, symbolized by the arrow H is not troublesome, insofar as the light 60 authorizes the resulting tilting of the control rod 32.

As soon as the torsional stresses which are applied by the boot on the plate 1 and against the jaws 31 of the front stop stop, the tongue 62 regains its normal rectilinear shape while the front stop returns to its position centered on the ski , bringing the movable plate into this same position.

In the variant of Figure 6, the pivot axis of the support plate 1, referenced Z is not materialized by a cylindrical stud. The guide of the plate 1 is ensured by a part, or rib 27, having an outline in an arc of a circle integral with the mounting plate of the front stop. In the plate 1, for example in the underside of the plate, a groove of complementary shape is formed in which the rib 27 engages. The radius of curvature R is such that the axis Z is located in a zone corresponding to the average axis of rotation of the shoe in the binding, for example at the level of the tibia.

Of course, suitable means, not shown, are provided which hold the movable plate on the rib 27.

The operation of the device according to the present variant is identical to that which has just been described, the plate 1 being kinematically connected to the front stop via the elastically deformable member 6.

In the second embodiment of the invention, which is the subject of the representation of Figure 7, the movable support plate is of identical or similar design to that of Figures 1 to 5. The front stop is different type. It is a front stop of the same general type as those described for example in documents DE-A-3,539,969 and DE-A-3,905,445. It comprises a pair of parallel longitudinal rods 70 which are articulate at the front on vertical axes 71. At their end directed towards the rear, the rods 70 are articulated on a cross-member 73 by means of axes 75. On these same axes are articulated the jaws 72 serving to retain the tip of the shoe. An elastic mechanism, not shown, makes it possible, in a well known manner, to normally maintain the rods 70 parallel to the axis of the ski while keeping the two jaws 72 closed.

In the event of excessive torsional stress, tripping takes place in two stages. The rods 70, in a first phase, pivot jointly as is symbolized by the arrows I while the cross member 73 moves transversely (arrow J ). The actual triggering mechanism, which is not shown, is such that beyond a certain transverse displacement stroke, at least the outer jaw 72 is free to pivot outward, as symbolized by arrow K. The shoe can then, in a second phase, disengage from the binding.

According to the present invention, the crosspiece 73 carries a control rod 74. This is completely similar to the rod 32 fitted to the front stop of the first embodiment. The rod 74 engages in a slot 60 provided at the end of the elastic member 6. During the first phase of release (arrow J ) the movable plate is consequently driven, and pivots around the axis Y (arrow G ).

The elasticity of the connecting member 6, which gives the movable plate 1 a certain freedom of movement relative to the cross-member 73, is particularly advantageous at the end of the first release phase, when the jaw 72. At this time, in fact, although the movement of the cross-member 73 ceases, the support plate can continue its movement in the direction of release, which avoids the appearance of a hard point at the time of l shoe exhaust.

The front stop fitted to the device shown in FIGS. 8 and 8A is of the type comprising a pair of independent bent jaws (or wings) 85 which are articulated on a fixed body 80 and each act on a central slide 81 elastically biased by a spring 84 This acts against the head 82 of the slide 81 in order to move it towards the front of the ski. At its rear part, the slide carries a base 83 which is applied against the parts of the jaws 85 which are bent towards the inside of the ski. The axes of articulation of the jaws have been designated by the reference 850.

This type of attachment is described, for example, in document FR-A-2 609 900. The object thereof is a movable anti-friction plate which is integral with a cam track, and the slide which forms part of the fixing release mechanism is connected to a follower member engaging against this cam path. Thus, it is the internal elastic system at the front stop which ensures the centering and the return of the anti-friction plate on the ski. When one of the jaws of the binding is stressed by the boot and pivots towards the outside of the ski, it causes the slide to move backwards against the elastic system. This has the effect of separating the follower member from its cam path, which allows the transverse movement of the anti-friction plate. In this case, the movement of the support plate is therefore also governed by the movement of the stop-front jaw.

This same principle is found in the embodiment of Figures 8 and 8A.

The support plate 1, similar to that already described, can pivot around the Y axis. This plate 1 is integral with a cam path 19 which takes the form of an obtuse angle "V" whose point is directed towards the front of the ski. The cam surface is for example formed in the underside of the plate 1. The slide 81 extends, beyond the base 83, towards the rear of the ski by an elastic connecting member 9. It is a question of 'a flexible rod 90 whose end is bent at a right angle (vertically). This end, referenced 91 comes to bear against the cam surface 19.

Under the effect of the spring 84, the two arms 85 are normally folded inwardly of the ski and grip the toe of the boot, retaining the latter in a position centered on the ski. The curved end 91 of the member 9 is trapped in the bottom (top) of the "V" cam 19, keeping the plate 1 centered on the ski.

If the skier's leg is subjected to excessive torsional stress, his shoe pushes one of the jaws 85 laterally as is symbolized by the arrow P in FIG. 8. The jaw pivots around its axis 850, compressing by the intermediate of its bent part and of the slide 81 the spring 84. The slide moves longitudinally towards the rear of the ski, as symbolized by the arrow U. The follower member 91 therefore tends to come off the cam track 19, which allows lateral pivoting of the pivoting plate 1. If the shoe is in contact against the support plate 1, the latter effectively pivots, faithfully following the path of the shoe, as symbolized by the arrow R.

Consequently, an angular offset is created between the axis Xo of the ski and the axis X of the support plate. According to the invention, the plate 1 can still pivot slightly, in an elastic manner, relative to this "average" position X. This is possible thanks to the flexibility of the rod 90, the deformation of which is shown in FIG. 8A. The additional pivoting of the plate is symbolized by the arrow R ' .

Claims (9)

1. Front safety stop for a ski, comprising a movable element, e.g., jaws carried by a body (33), a pair of jaws (72) jointed to a cross-piece (73), a pair of independent, curved jaws (85), comprising a device for supporting the front of the boot with a movable sole-supporting plate (1), and guide means (24-13; 27, 18) independent of those of the movable element ensuring displacement of the support plate according to a predetermined path having a component traverse to the ski, the support plate being connected to the movable element by a connection piece (6, 9), characterized by the fact that the connection piece (6, 9) is elastically deformable, so that the support plate can move freely in a resilient manner on a weak course relative to a mean position which is imposed on it by the release movement of the movable element.
2. Stop according to claim 1, characterized by the fact that the connection piece (6, 9) is a flexible tongue.
3. Stop according to one of claims 1 and 2, characterized by the fact that the movable plate (1) can pivot laterally around an axis (Y, Z) centered on the ski and located beneath the boot.
4. Stop according to claim 3, characterized by the fact that the means ensuring guidance for the pivoting of the movable plate (1) consist of a stationary cylindrical stub (25) which engages in a hole (13) in the plate (1).
5. Stop according to claim 3, characterized by the fact that the means ensuring guidance for the pivoting of the movable plate (1) consist of a stationary rib (27) having a circular arc-shaped contour, which engages in a complementary groove (18) provided in said plate (1).
6. Stop according to one of claims 1 to 5, characterized by the fact that it is of the pivoting body (33) type carrying the retaining jaws (31) of the boot, and that the pivoting body (33) is solid with a substantially vertical rod (32), centered on the ski, and fastened to the connection piece (6) (Figures 1 to 6).
7. Stop according to claims 2 and 6 taken in combination, characterized by the fact that the said rod (32) engages in a slot (60) provided in one of the ends of the flexible tongue (62), the same being connected, by its other end, to the movable plate (1).
8. Stop according to one of claims 1 to 5, characterized by the fact that it is of the type comprising a pair of jaws (72) articulated on a transversely movable cross-piece (73), and that this latter is connected to the said connection piece (6) (Figure 7).
9. Stop according to one of claims 1 to 5, characterized by the fact that it is of the type comprising a pair of independent, curved jaws (85) which are articulated on a stationary body (80) and each act on a central elastically-stressed slider (81), and that the support plate (1) is solid with a cam groove (19) which cooperates with a tracking piece (91), this latter being connected to said slider (81) by the said elastically-deformable connection piece (9) (Figures 8 and 9).

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