EP0102868B1 - Front jaw for a safety ski binding - Google Patents

Abstract

A toe-abutment member providing safety ski boot release in the event of a backward-fall movement combined with a twisting movement of the skier's leg comprises a fixed locking member having an inclined ramp and an abutment body pivotally mounted on a cross-pin. The jaw unit for retaining the toe end of the ski boot is movably mounted within the abutment body and carries a transverse rod which is applied against the ramp by means of a spring-loaded piston.

Description

The present invention relates to a front safety stop for skiing.

• La butée avant permet l'échappement latéral de la chaussure lorsqu'un effort de torsion excessif apparaît sur la jambe du skieur; la talonnière autorise l'échappement vertical du talon lorsque la jambe est soumise à un effort excessif de flexion vers l'avant:
• On connaît également, par exemple par DE-A-2 637 871, des butées avant permettant un échappement vertical de la pointe de la
• chaussure lorsque le skieur est soumis à une chute vers l'arrière, grâce à une articulation du corps de la butée autour d'un axe porté par une plaque de base appliquée sur le ski, cet axe étant situé à la partie avant du corps de la butée.

Modern safety bindings generally consist of two elements intended to retain the boot on the ski; the front stop which cooperates with the toe of the shoe and the heel which cooperates with the heel of the shoe:

• The front stop allows the lateral escape of the boot when an excessive torsional force appears on the skier's leg; the heel allows the vertical escape of the heel when the leg is subjected to an excessive forward bending force:
• Also known, for example from DE-A-2 637 871, front stops allowing vertical exhaust from the tip of the
• boot when the skier is subjected to a fall backwards, thanks to an articulation of the body of the stopper around an axis carried by a base plate applied to the ski, this axis being located at the front part of the body of stop.

Furthermore, front stops have been proposed in which the shoe tip retaining jaw can not only pivot to release the shoe laterally but can also move forward in the event of a longitudinal thrust exerted by the shoe. Thus, in the front stop described in FR-A-2 395 046 the jaw is slidably mounted on the body of the front stop. The system for locking the stop body in rotation on its axis comprises a piston applied elastically against a flat formed on the axis; under a high axial thrust the jaw moves forward and pushes the piston off the flat; the abutment body can then rotate freely on its axis. Thanks to this arrangement, the parasitic friction generated by the axial thrust between the shoe and the front stop is automatically compensated, the duration of the opening of the stop being maintained at a practically constant level.

The subject of the invention is a front stop which allows both tripping in rear fall and compensating for parasitic friction due to an axial thrust, while being of relatively simple and light construction, of a low cost price and reliable operation.

• - une plaque de base destinée à être fixée sur la face supérieure du ski et qui porte une pièce approximativement verticale, dite pièce de verrouillage pourvue d'une partie déstinée au verrouillage appelée moyen de verrouillage, et qu'est orientée vers la pointe du ski,
• - un corps articulé sur la plaque de base autour d'un axe transversal
• - une mâchoire de retenue de la pointe de la chaussure, qui est guidée dans un logement du corps avec possibilité de se déplacer en rotation et en translation vers l'avant
• - un piston mobile dans le corps parallelement à l'axe longitudinal du ski
• - un organe élasique logé dans le corps et agencé pour exercer sur le piston une sollicitation dirigée vers le talon du ski
• - deux éléments d'appui solidaires de la mâchoire et ayant leur face d'appui utile dirigée pour le premier vers la pointe et pour le second vers le talon du ski, le piston étant appliqué élastiquement par sa face arrière contre ledit premier élément d'appui et que le second élément d'appui étant appliqué élastiquement contre le moyen de verrouillage.

To this end, the front stop according to the invention is characterized in that it comprises:

• - A base plate intended to be fixed on the upper face of the ski and which carries an approximately vertical part, said locking part provided with a part intended for locking called locking means, and which is oriented towards the tip of the ski ,
• - a body articulated on the base plate around a transverse axis
• - a jaw retaining the tip of the shoe, which is guided in a housing of the body with the possibility of moving in rotation and in forward translation
• - a piston movable in the body parallel to the longitudinal axis of the ski
• - an elastic member housed in the body and arranged to exert on the piston a stress directed towards the heel of the ski
• - two support elements integral with the jaw and having their useful support face directed for the first towards the tip and for the second towards the ski heel, the piston being applied elastically by its rear face against said first element support and the second support element being applied elastically against the locking means.

In a simple manner, the locking of the body on the ski is resolved by means of a ramp cooperating with a rod or a transverse rotary roller.

Furthermore, the piston can cooperate with the jaw by means of flat bearing faces or by means of a vertical roller engaging in a V-shaped housing (dihedral).

• - la figure 1 est une vue de face d'un exemple de réalisation de butée avant conforme à l'invention;
• - la figure 2 est une vue de face de la même butée avant, coupée par le plan vertical II-II de la figure 3;
• - la figure 3 est une vue de dessus coupée par le plan brisé III-III de la figure 2;
• - les figures 4 et 5 sont des vues de détail respectivement en vue de face et en vue de gauche de la pièce de verrouillage portée par la plaque de base;
• - la figure 6 est une vue analogue à la figure 3 montrant un déclenchement en torsion;
• - la figure 7 est une vue partielle, analogue à la figure 3 montrant la butée avant soumise à un effort de poussée longitudinale;
• - la figure 8 est une vue analogue à la figure 2 montrant un déclenchement en chute arriére;
• - la figure 9 est une vue de dessus partielle, en section selon le plan IX-IX de la figure 8;
• - la figure 10 est une vue de dessus partielle coupée, analogue à la figure 3 d'une première variante dé la butée avant des figures 1 à 9;
• - la figure 11 est une vue analogue à la figure 10, montrant un déclenchement en torsion;
• - la figure 12 est une vue face coupée, analogue à la figure 2, d'une seconde variante de la butée avant des figures 1 à 9.

The invention will be better understood and its features and advantages highlighted thanks to the description which will now be made with reference to the accompanying drawings:

• - Figure 1 is a front view of an exemplary embodiment of the front stop according to the invention;
• - Figure 2 is a front view of the same front stop, cut by the vertical plane II-II of Figure 3;
• - Figure 3 is a top view cut by the broken plane III-III of Figure 2;
• - Figures 4 and 5 are detail views respectively in front view and in left view of the locking piece carried by the base plate;
• - Figure 6 is a view similar to Figure 3 showing a torsional release;
• - Figure 7 is a partial view, similar to Figure 3 showing the front stop subjected to a longitudinal thrust force;
• - Figure 8 is a view similar to Figure 2 showing a trigger in rear fall;
• - Figure 9 is a partial top view, in section along the plane IX-IX of Figure 8;
• - Figure 10 is a partial cut away top view, similar to Figure 3 of a first variant of the front stop of Figures 1 to 9;
• - Figure 11 is a view similar to Figure 10, showing a torsional release;
• FIG. 12 is a cutaway view, similar to FIG. 2, of a second variant of the front stop of FIGS. 1 to 9.

The front stop of FIGS. 1 to 9 comprises a base plate 1 fixed on the upper face of the ski S by screws (not shown). The tip of the ski is located on the left of the figures.

At its front part the base plate 1 is provided with a pair of side cheeks 2 extending vertically and supporting a transverse are 3 immobilized in translation by riveting its axtremities. The body 4 of the front stop is articulated around the axis 3, between the cheeks 2.

In its central area, the plate 1 carries a lock piece 5 which is approximately vertical; the part 5 can be fixed to the plate 1 by any suitable means such as welding or riveting, or form an integral part thereof. The part 5 is provided with a locking means constituted by a ramp 6 facing the front of the ski and inclined from bottom to top when moving towards the front. The lateral edges 5a, 5b of the part 5 have a cylindrical configuration. In the example shown, the ramp 6 is a flat surface; the line of intersection of this surface with the cylindrical edges of the part 5 is therefore an ellipse whose width "a" decreases from bottom to top.

The part 5 penetrates inside the body 4 through an opening 7 made in the underside thereof. The opening 7 is dimensioned so that the part 5 does not interfere with the pivoting of the body 4 around the axis 3.

The front stop comprises a jaw 8 for retaining the tip of the shoe (not shown). The jaw comprises a pair of lateral arms 9 advantageously provided with anti-friction linings 10. The jaw 8 is optionally provided with means for adjusting the height and width of the arms 9 so that the latter properly enclose the front part of the shoe (upper or sole).

These well-known adjustment means have not been shown for the sake of simplification. Furthermore, the base plate 1 is provided with a sliding plate 11 intended, as also well known, to support the underside of the front part of the sole.

In çorps4 is provided a housing 12 which has lower walls 12a and upper 12b horizontal and which opens towards the rear of the ski.

The part of the jaw 8 located in front of the arms 9 has a thickness equal to the height of the housing 12. This part is disposed inside the housing 12 and is guided there by the horizontal walls 12a, 12b; it has an approximately rectangular central opening which surrounds the attachment part 5. The opening 13 has a longitudinal dimension greater than that of part 5 and a transverse dimension equal (apart from a functional clearance) to the dismeter of the cylindrical part of the part 5. At the front part of the opening 13 is arranged a transverse rod 14 which has been secured to the jaw 8 by riveting its ends.

The jaw 8 has a flat front end face 15. In the front part of the body 4 is hollowed out a cylindrical bore 16 parallel to the longitudinal axis of the ski. At the front, this bore is closed by a threaded plug 17, while at the rear it communicates with the housing 12. A piston 18 in the form of a cylindrical sleeve is slidably mounted in the bore 16. A compression spring helical 19 bearing against the plug 17 acts against the piston to move it backwards so as to apply it by its face 20 against the front face of the jaw 8. In turn the latter is urged backwards and the transverse rod 14 is applied against the ramp 6 of the locking piece 5.

This front stop works as follows: Under normal skiing conditions, the jaw occupies the position of FIGS. 2 and 3 and keeps the toe of the boot centered on the ski.

When a torsional force acts on the skier's leg, the boot exerts against one of the arms 9 a horizontal transverse force F (H) tending to cause the jaw 8 to tilt laterally. If the force F (H) is sufficiently high , the jaw effectively tilts in its housing 12, in a horizontal plane. During this movement, illustrated in Figure 6, the rod 14 bears against one of the edges of the ramp 6, while the face 15, by one of its edges, pushes the piston 18 back inside its bore 16 by compressing spring 19.

If the force F (H) is large enough and lasts long enough to constitute a danger of injury to the leg, the jaw 8 rocks at an angle such that it lets the tip of the shoe escape laterally; otherwise the piston 18 recalls the jaw in its normal position of Figure 3, which causes the refocusing of the boot on the ski.

During skiing it frequently happens that the jaw of the front stop is subjected on the part of the tip of the boot to longitudinal thrusts directed towards the front. These thrusts appear in particular in the event of an imbalance of the skier forwards (which causes stress when the heel opens), in the event of accentuated bending of the ski (during which the boot is compressed between the heel and the stop-front) or in case of abrupt deceleration of skiing (as a result for example of the arrival of the ski in fresh ungroomed snow).

The longitudinal thrust generates parasitic friction which is located on the one hand between the tip of the shoe and the arms of the front stop, on the other hand between the underside of the sole and the sliding plate.

In the front stop according to the invention, a relatively high longitudinal thrust F (L) causes the jaw 8 to move forward. In this movement its front face 15 pushes the piston 18 back into its bore, compressing the spring 19, while the rod 14 is detached from the ramp 6 by a distance "e" (proportional to F (L). We see that 'From the position of Figure 7, which illustrates this situation, the jaw 8 is free to tilt laterally on one side or the other of the axis of the ski, until the rod 14 comes meet an edge of the ramp 6 (position in FIG. 6). Thanks to this freedom of tilting, the parasitic friction which is mentioned above is somehow compensated and the front stop has a hardness to trigger in torsion. practically constant.

Figures 8 and 9 illustrate the situation of the skier falling backwards. In this situation the edge of the sole of the front part of the shoe exerts a vertical force F (V), directed upwards, under the arms 9. If this force is high enough, the body 4 is lifted by pivoting around the axis 3. During this lifting the rod 14 runs along the ramp 6 and causes the jaw 8 to slide inside the body 4 towards the tip of the ski, compressing the spring 19. The jaw therefore describes a double movement of pivoting upwards and of translation towards the front which allows a particularly soft and safe release of the toe of the shoe. It is possible to provide a stop stop limiting the lifting of the body to prevent that, at the end of the stroke, the rod 14 does not leave the locking part 5.

Because the width "a" of the ramp 6 decreases from bottom to top, the contact line between the rod 14 and this ramp is shorter when the jaw is in the raised position (FIG. 9) than in the normal position ( figure 3). As a result, the torsional retention torque of the jaw is lower when it is raised than when it is in the normal position. Thus, in the event of a combined rear-torsion fall, a practically constant torsional tripping hardness is obtained, the parasitic friction located between the sole and the underside of the jaw arms being compensated for by the reduction in the lever arm "a". This result is also achieved in all other cases where the sole is pinched too strongly by the arms of the jaw, in particular in the event of an error in adjusting the jaw in height or in the presence of a layer of snow. under the sole.

It should be noted that even in the event of lifting of the jaw, due to one of the causes which have just been stated, it is kept perfectly centered on the ski, the cooperation between the piston 18 and the flat face 15 d on the one hand and between the rod 14 and the ramp 6 on the other hand being preserved; there is therefore no floating of the tip of the boot in the front stop, which is essential to allow good handling of the skis.

In the first variant of FIGS. 10 and 11, the piston 18 has a rear face 21 in the form of a dihedron with vertical planes and with a rounded bottom, while the jaw 8 is provided on its front face with a vertical roller 22 free to rotate. The spring 19 urges the piston 18 so as to apply the bottom of the dihedral 21 against the roller 22 and, as in the preceding reslisation, the rod 14 against the ramp 6.

In the event of the appearance of a high transverse force F (H) the jaw 8 rocks laterally as shown in FIG. 11. During this movement the rod 14 bears against one of the edges of the ramp 6 while the roller 22, which tends to come out of the dihedral 21, pushes back the piston 18 by compressing the spring 19.

Under a longitudinal thrust F (L) and under a vertical force F (V) the behavior of this variant is identical to that of the previous embodiment.

In the second variant of Figure 12 the locking piece 23 has the shape of a vertical yoke carrying a transverse roller 24 free in rotation; the latter is in abutment against an inclined ramp 25 formed or attached to the jaw 8. In the event of a rear fall (not shown) the roller 24 acts against the ramp 25 to push the jaw 8 forward and compress the spring 19. The ramp 25 preferably has a decreasing width from top to bottom so that, as in the embodiment of FIGS. 1 to 9, the natural hardness of triggering in torsion decreases as the jaw is raised. In the event of torsion and under longitudinal thrust, this variant operates in the same way as the embodiment of FIGS. 1 to 9.

Without departing from the scope of the invention, it is possible to provide various modifications to the embodiments which have just been described by way of example. Thus the transverse rod 14 could be replaced by a rotary roller so as to reduce the internal friction of the stop. Furthermore, the ramp controlling the triggering in rear fall is not necessarily flat; one could provide a curved ruled surface.

In the variant of FIGS. 10, 11 it would be possible to mount the roller 22 on the piston 18 and to produce the dihedral housing 21 on the front face of the jaw 9.

The various lever arms governing the torsional and rear falling triggers are determined in such a way that the force F (H) for torsional triggering is approximately 5 or 6 times less than the force F (V) for triggering rear fall; Track tests have shown that this hardness ratio allows you to ski in complete safety, without accidental trips. Of course, it is possible to modify these trigger hardnesses as a function of the skier's morphology by operating the adjustment cap 17.

Instead of providing ramps 6.25 whose width varies progressively in the vertical direction, it could be provided, without departing from the scope of the invention, that these ramps are simply made up of two staged sections of different width: a section of large intex enant width to determine the triggering hardness in pure torsion and a small width section, even partially null, intervening to determine the triggering hardness in torsion when the jaw is raised, whatever the value of this lifting.

Although the safety binding which has just been described has been designed to retain the toe of the shoe, one could consider using it as a heel with triggering in front fall and torsion; for that it would be enough to replace the jaw with an appropriately shaped grippetalon.

Claims (10)

1. Safety toe abutment member for a ski, comprising:

- a base plate (1) which is intended to be fixed on the top face of the ski and carries an approximately vertical member referred to as a locking member (5 ; 23) provided with a portion for performing the tocking operation (6 ; 24) which is designated as a locking means and which is directed towards the front tip of the ski,

- a body (4) mounted on the base plate for pivotal displacement about a transverse axis (3)

- a jaw unit (8) for retaining the toe end of the ski boot, which is guided within a housing (12) of the body (4) with a possibility of rotational displacement and translational displacement in the forward direction,

- a piston (18) capable of displacement within the body (4) in a direction parallel to the longitudinal axis of the ski,

- and a resilient member (19) housed within the body (4) and so arranged as to exert on the piston (18) a force which is directed towards the heel of the ski,

characterized in that it comprises two bearing elements (15,22; 14,25) rigidly fixed to the jaw unit (8), the useful bearing face being directed towards the tip of the ski in the case of the first bearing element (15, 22) and towards the heel of the ski in the case of the second bearing element (14, 25), the piston (18) being resiliently applied by means of its rear face (20, 21) against the first bearing element (15,22), the second bearing element (14, 25) being resiliently applied against the locking means (6,24).

2. Toe abutment member in accordance with claim 1, characterized in that the jaw unit (8) has a central opening (13) which surrounds the locking member (5) and has an approximately rectangular shape which permits translational displacement of the jaw unit (8) in the forward direction and lateral pivotal displacement of said unit with respect to the locking-member (5).

3. Toe abutment member in accordance with any one of the preceding claims, characterized in that the locking means is a ramp (6) which cooperates with the second bearing element (14) in the form of a transverse rod or roller.

4. Toe abutment member in accordance with claim 3, characterized in that the ramp (6) has a width "a" which decreases from the bottom upwards.

5. Toe abutment member in accordance with claim 4, characterized in that the ramp (6) is flat.

6. Toe abutment member in accordance with either of claims 1 or 2, characterized in that the locking means is a transverse roller (24) which cooperates with the second bearing element (25) in the form of a ramp.

7. Toe abutment member in accordance with claim 6, characterized in that the ramp (25) has a width which decreases from the top downwards.

8. Toe abutment member in accordance with claim 7, characterized in that the ramp (25) is flat.

9. Toe abutment member in accordance with any one of the preceding claims, characterized in that the first bearing element (15) is constituted by the flat front face of the jaw unit (8) which is so arranged as to cooperate with the rear face (20), which is also flat, of the piston (18).

10. Toe abutment member in accordance with any one of claims 1 to 8, characterized in that the first bearing element (22) is a freely rotatable roller having a vertical axis and adapted to cooperate with the rear face (21) of dihedral shape of the piston (18).

Images