EP0031740B1 - Front jaw for a ski binding - Google Patents

Abstract

This toe-fitting for safety ski binding is of the type intended for operating in conjunction with a boot supporting device and includes a boot supporting plate movable across the ski and adapted, during its movement, to cause through a cam mechanism the translation along the ski axis of a slide controlling the release spring in order to reduce the resistance thereof to the ski boot release movement, the release threshold being thus kept to a substantially constant value notwithstanding the presence of dirt, mud or other unevennesses on the bottom surface of the boot sole.

Description

The present invention relates to a ski safety binding and more specifically the front stop of a ski safety binding.

Conventional safety bindings, by far the most widespread, consist of two parts intended to retain the boot on the ski: a stop-front which cooperates with the front part of the shoe-sole or upper - and a heel piece which cooperates with the heel of the shoe.

In the event of excessive effort urging the skier's leg in torsion, the front stop member in contact with the boot moves in a direction approximately transverse to the ski against a preset elastic device and releases the boot ; in the event of excessive vertical effort, due to a fall of the skier forwards, the heel member retaining the heel moves in an approximately vertical direction, also against a preset elastic device and releases the shoe.

To prevent significant friction from dangerously thwarting the release in torsion, by creating parasitic forces adding to the own tripping force of the front stop, these known fasteners are equipped with an anti-friction device serving as a support for the standardized and smooth front part of the sole. They are generally wafers made of a material with a low coefficient of friction such as PTFE, or else rolling elements such as rollers or rotating discs. These well known safety bindings give complete satisfaction under normal conditions of skiing and offer the skier very good security.

Some of these bindings include special arrangements or additional improvements to prevent the shoe release conditions from being disturbed by certain specific operating conditions.

Thus, the European patent applications _' EP-A-25 747 and EP-A-30 175, published after the priority date of this application, describe fasteners of the type in question, which are provided with a device capable of reduce the importance of the resistance to the release of the boot by the retaining jaw, when the skier is leaning forward and / or back. These devices are intended to act in the event of so-called "combined" falls, that is to say falls causing both a torsional force on the foot and an extension force on the leg either forwards, either backwards.

However, these devices are of no use when the operating conditions of a binding of the type in question are disturbed by poor sliding of the boot on the top of the ski.

However, when the shoe and / or the binding are dirty, the friction appearing between the shoe and the anti-friction device can reach a high and dangerous level. This difficulty is encountered in particular in summer ski resorts where skiers have to walk for a long time on ground that is not snow-covered, and often covered with mud and gravel, before reaching the snow-covered areas where they put their skis on. Excessive and irregular wear under the sole can also pose the same problem by excessively increasing its coefficient of friction.

During skiing, the improper sliding of the boot on the ski is further amplified when the skier is in the forward leaning position. Indeed, the weight of the skier tends to strongly apply the sole to the anti-friction device so that the dirt and / or the roughness of the sole in poor condition become encrusted in it and prevent lateral release of the shoe. .

Patent applications FR-A-2395763 and FR-A-2403092 describe fasteners designed to try to solve this problem. To this end, in one and the other of the front stops which are the subject of these requests, the jaw and the support plate of the front of the chase are constituted by a single piece, in one piece. Furthermore, to avoid any sliding between the shoe sole and the support plate, the arrangement is such that this jaw-support plate assembly is brought to describe a circular path centered at the heel (pivot point of the shoe in the binding). But to allow the shoe to escape, the jaw must also advance or tip outwards after a certain opening angle. This arrangement therefore requires relatively complicated and consequently expensive guiding of the jaw-support plate assembly.

In addition, as a result of brief and non-dangerous side impacts occurring "empty", that is to say when there is no pressure of the shoe on the support plate, these impacts not causing the release of the boot, the elastic system of the binding must operate the centering in the axis of the ski of the jaw-support plate assembly. However, due to the high inertia of this assembly, the time of this refocusing is relatively long and the binding therefore has poor dynamic behavior.

This is why the object of the present invention is to solve, by different means, the problem thus posed in order to produce a front stop whose trigger hardness is practically independent of the state of cleanliness or deterioration of the sole.

To this end, the front stop object of the invention comprises a shoe retaining jaw movable laterally against an elastic system with preset hardness and is associated with a device intended to support the front part of the sole, the latter comprising at least one movable member capable of being driven by the transverse displacement of the sole. According to the invention, this movable member is independent of the jaw and there is provided a connecting slide between the elastic device and the movable member, this slide being maneuvered by this movable member, by means of ramps or cams, and being able to lower the retention hardness of the shoe when the movable member is driven laterally by the latter.

In the illustrated embodiments of the invention, the connecting slide between the movable member and the elastic system is guided in translation in the base of the front stop. As for the movable member, it preferably affects the shape of a plate which can move in a direction approximately transverse to the ski and in particular along a circular arc path centered on the pivot point of the boot in the binding. ; this arrangement makes it possible to avoid any sliding of the shoe relative to its support device. In a simple manner, the transmission of movement between the movable plate and the slide is achieved by means of a cam or articulated levers.

In a particularly advantageous embodiment of the invention, the slider has an extension serving as a support member at the front of the sole so that the slider is moved and the retaining hardness of the front stop is lowered, due to the inclination of the shoe due to a forward fall.

The invention will be better understood during the description which follows, with reference to the appended drawings which represent the three embodiments which have been chosen by way of examples to make the invention understood.

• - La figure 1 est une vue de face.
• - La figure 2 est une vue de dessus coupée selon le plan II-II de la figure 3.
• - La figure 3 est une vue de face en coupe longitudinale selon le plan III-III de la figure 5.
• - La figure 4 est une section transversale selon le plan IV-IV de la figure 3.
• - La figure 5 des une vue analogue à la figure 2 montrant le fonctionnement de la butée-avant dans le cas où les frottements entre la semelle et son support sont faibles.
• - La figure 6 est une vue analogue à la figure 1 montrant une chaussure encrassée et inclinée engagée dans la butée-avant.
• - La figure 7 est une vue analogue à la figure 2 montrant le fonctionnement de la butée-avant dans Ii cas où les frottements entre la semelle et son la semelle et son supp_or

Figures 1 to 7 show a first embodiment of the front stop according to the invention, mounted on a ski and in which is engaged the front part of a ski boot.

• - Figure 1 is a front view.
• - Figure 2 is a top view cut along the plane II-II of Figure 3.
• FIG. 3 is a front view in longitudinal section along the plane III-III of FIG. 5.
• - Figure 4 is a cross section along the plane IV-IV of Figure 3.
• - Figure 5 of a view similar to Figure 2 showing the operation of the front stop in the event that the friction between the sole and its support is low.
• - Figure 6 is a view similar to Figure 1 showing a dirty and inclined shoe engaged in the front stop.
• - Figure 7 is a view similar to Figure 2 showing the operation of the front stop in Ii case the friction between the sole and its sole and its supp _or

• - La figure 8 est une vue de face en coupe longitudinale.
• - La figure 9 est une vue de dessus en coupe selon le plan IX-IX de la figure 8.
• - La figure 10 est une vue analogue à la figure 8 montrant une chute-avant.
• - La figure 11 est une vue analogue à la figure 9 montrant le fonctionnement de la butée-avant dans le cas où les frottements entre la semelle et son support sont élevés.

Figures 8 to 11 show a second embodiment of a front stop according to the invention.

• - Figure 8 is a front view in longitudinal section.
• - Figure 9 is a top view in section along the plane IX-IX of Figure 8.
• - Figure 10 is a view similar to Figure 8 showing a front drop.
• - Figure 11 is a view similar to Figure 9 showing the operation of the front stop in the event that the friction between the sole and its support is high.

• - La figure 12 est une vue de dessus partiellement coupée.
• - La figure 13 est une vue analogue à la figure 12 montrant le fonctionnement de la butée-avant dans le cas où les frottements entre la semelle et son support sont élevés.
• - La figure 14 est une vue analogue à la figure 12 montrant le fonctionnement de la butée-avant dans le cas où les frottements entre la semelle et son support sont faibles.
• - La figure 15 est une section partielle selon le plan XV-XV de la figure 12 montrant certains éléments de la butée-avant en vue de face.

Figures 12 to 15 show a third embodiment of a front stop according to the invention.

• - Figure 12 is a partially cut top view.
• - Figure 13 is a view similar to Figure 12 showing the operation of the front stop in the event that the friction between the sole and its support is high.
• - Figure 14 is a view similar to Figure 12 showing the operation of the front stop in the event that the friction between the sole and its support is low.
• - Figure 15 is a partial section along the plane XV-XV of Figure 12 showing some elements of the front stopper in front view.

Figures 1 to 7 show a first embodiment of a front stop according to the invention.

This consists of a body 1 mounted on the ski 2 by means of screws 3 and a jaw 4 articulated on the body 1 around a vertical axis 5.

The shoe 6 is supported by the front part of its upper against linings 7 clipped to the arms of the jaw 4 and whose material has good sliding characteristics. It rests by its smooth part 8, the position and the sliding coefficient of which are normalized, on a support device designated by the general reference 9. This device comprises a slide 10 fixed to the ski by screws 11 and having a T-section as well as a circular arc shape whose center approximately coincides with the pivot axis of the shoe in the binding. The slide 10 serves as a guide for a movable plate 12 provided with a groove of complementary section. A support plate 13 secured to the plate 12 supports the underside of the sole 8.

The plate 12 is provided with an appendage 14 located on the axis of the ski 2 and directed towards the front thereof. Appendix 14 carries a roller 15 which can rotate freely around a vertical axis and bears against a concave cam 16, in the shape of a very open V, formed on a piece 17. The piece 17 is fixed, by any suitable means, to the rear end of a slide 18 which can slide on a slide 20 fixed to the ski by screws 21 .

The elastic system housed in the abutment body 1 comprises a set of springs 22 which bears against a plate 23 and urges a piston 24 slidably mounted in the body 1. The piston 24 has a flat head 25 which, in known manner, acts against a flat part 26 formed on the back of the jaw 4 in order to maintain the latter elastically centered along the axis of the ski. A screw 27 is used to adjust the hardness of the springs 22.

At its front part, the slide 18 has a vertical extension 19 which, according to the invention, is interposed between the piston head 25 and the flat part 26 of the jaw 4.

Finally, note the presence of stops 29 intended to cooperate with the appendix 14 to limit the lateral movement of the plate 12 in order to prevent it from coming off the ski. The stops 29 are integral with the slide 10; elongated openings formed in the front wall of the plate 12 allowing the latter to slide despite the presence of the stops 29.

We will now describe the operation of this front stop, first assuming that the boot is clean and in good condition, and that the skier's weight is normally distributed, the boot being flat on the ski (Figure 3 ). Under these conditions the pressure exerted by the sole on the support plate 13 is relatively low and practically does not obstruct the escape of the shoe during a torsional movement. In fact, during this escape, only the jaw 4 tends to elastically retain the boot centered on the ski. If the torsional force exerted on the skier's leg is excessive, in one direction or the other, the jaw 4 turns around its axis 5 in the corresponding direction and, by an edge of its flat part 26, pushes the piston 24 against the springs 22, possibly until the shoe is completely released.

This operation is well known, as that of a traditional front stop. The presence between the jaw 4 and the piston 24 of the extension 19 of the slide 18 causes the displacement of the latter on its guide 20 during the rotation of the jaw 4. However, this fact does not in any way modify the behavior of the stop by compared to that of a conventional stop.

Indeed, the retention hardness of the shoe is exerted only by the elastic system 22, 24.

We will now assume that the underside of the boot is dirty or deteriorated and that the skier is also in a position leaning forward.

This situation is shown in Figure 6, in which we note the inclined position of the shoe (the not shown heel is raised) and the presence under it of roughness 28 showing its fouling and / or wear. The application of the weight of the skier to the support device 9 and the presence of roughness 28 under the sole generate on the support plate 13 high friction forces.

If a significant torsional force is exerted on the skier's leg, the front of the shoe begins to disengage laterally, by rotating the jaw 4, against the elastic system 22, 24. Due to friction high the support plate 13 tends to follow the movement of the shoe and the plate 12 begins to move laterally on its slide 10. During this movement, the roller 15 carried by the plate 12 cooperates with the cam 16 to push the slide 18 towards the front of the ski. The extension of the slide 19 therefore acts on the elastic system 22, 24 to compress it.

It is therefore seen that the elastic system 22, 24 is stressed simultaneously and in the same direction by the flat face 26 and by the extension 19.

By its movement, the plate 12 consequently facilitates the opening of the front stop by helping it to overcome the resistance of the elastic system 22, 24.

The profile of the cam 16 is preferably designed so that the pivoting of the shoe causes the same displacement of the piston 24 whether it be due to the rotation of the jaw 4 or due to the lateral displacement of the plate 12, assuming that 'There is no sliding of the sole on the support plate 13.

The extreme position of the plate 12 has been shown in phantom in Figure 7; this position preferably coincides with the position for releasing the shoe 6 from the jaw 4.

The operation of the front stop has been described for a release of the boot occurring to the right when looking at the tip of the ski. This operation would of course be identical for a clearance to the left because of the symmetry of this front stop.

Figures 8 to 1 show a second embodiment of a front stop according to the invention.

This comprises a body 30 which is rotatably mounted on a vertical pivot 31, in the form of a tube, integral with a base 32 fixed to the ski 2. The tube 31 has a flat countersunk part 33 forming a cam, facing forward ski. A piston 34 is slidably mounted in a cylindrical bore 35 of the body 30 and bears by its flat face 36 against the cam 33. The piston 34 is biased by a spring 37 which bears against an adjustment plug 38 screwed into the body 30.

Inside the tube 31 is mounted a lever 39 articulated around a transverse axis 40 integral with said tube. The lever 39 has a prominence 41 by which it bears against the central part of the piston 34.

The front part of the shoe 42 is applied against anti-friction linings 43 mounted on the lateral arms 44 forming integral parts of the body 30 and constituting the jaw of the front stop. The shoe 42 rests by its normalized smooth part on a support device similar to that described in the previous embodiment and constituted by a slide 46 in the form of an arc of a circle on which a plate 47 provided with a sole support plate 48. The plate 47 has an appendage 49 provided with a rotary roller 50. In the base 32 are mounted two levers 51 a, 51b articulated around vertical axes 52a, 52b, and each having a ramp 53a, 53b. These ramps are turned towards the boot, that is to say towards the rear of the ski, and are both in contact with the roller 50.

On the opposite side, facing the front of the ski, the levers 51 a, 51 b are provided with bosses 54a, 54b respectively which bear against a slide 55 mounted in the base 32 and guided to slide longitudinally therein. The front end of the slide 55 is in contact with the lower part of the lever 39 while its rear end forms a vertical extension 56 serving to support the front of the sole of the shoe.

If a high torsional force is exerted on the skier's leg, the boot 42 tends to escape transversely, causing in its movement one of the arms 44, which rotates the body 30 on the pivot 31. This triggering is produced against the elastic system constituted by the spring 37, the piston 34 and the cam 33.

If the underside of the soleplate is dirty or in poor condition, it also drives the plate 48 and the roller 50. The latter pressing against one of the ramps 53a or 53b, depending on the direction of movement, rotates the 'one of the levers 51 a, 51 b around its axis 52a, 52b, respectively.

In Figure 11 it is the lever 51 a which is driven. In turn it pushes the slide 55 by means of its boss 54a. The lever 39 is therefore biased and tends to push the piston 34 by means of the protrusion 41. This therefore facilitates triggering because the lever 39 contributes to acting against the elastic system 37, 34, 33.

FIG. 10 shows the function fulfilled by the vertical extension 56 of the slider 55. In the event of a pronounced inclination of the shoe (front drop), the front of the sole acts on the extension 56 and pushes the slider forward 55 so that the lever 39 is driven as previously to act on the piston 34.

In this second embodiment, a reduction in the retaining hardness of the front stop is therefore obtained not only in the event of the appearance of high friction between the sole and its support device but also in the event of inclination of the shoe in front drop.

It will be noted that the position of the bosses 54a, 54b on the levers 51 a, 51 b and the position of the boss 41 on the lever 39 make it possible to achieve a reduction in the force transmitted to the piston 34 from the roller 50.

Figures 12 to 15 show a third and last embodiment of a front stop according to the invention.

This consists of a body 61 fixed on the upper surface of the ski 2 and a jaw 64 cooperating with the front part of the shoe sole 62 to retain the latter centered on the ski. On the front face of the jaw 64 are formed two vertical grooves 71 which are applied elastically against the support beads 62 formed on the body 61 and which, in known manner, constitute knives for tilting the jaw 64. The elastic system acting on the jaw 64 comprises a set of springs 66, 67 mounted in series in the body 61. This set of springs bears against a shoulder 68 formed in the body 61 and acts on an adjustment plug 69 carried by a tie rod 65 which is articulated on the jaw 64 by means of a vertical axis 70.

In the base of the fixed body 61 is guided a slide 72 which can move along the axis of the ski. The slide 72 assumes the shape of an L, the vertical branch 73 of which is interposed between the springs 66 and 67.

The shoe 62 rests on a support device comprising a plate 77 provided with a support plate 78 and guided on a slide in an arc of a circle 74 in order to be able to slide transversely to the ski.

Under the plate 77 is formed a very open V-shaped concave cam 75, the apex of which faces the front of the ski, and against which a finger 76 fixed at the rear end of the slide 72 rests (Figure 15 ).

So that contact between the finger 76 and the cam 75 can be ensured whatever the precompression given to the springs 66, 67 by the adjustment plug 69, the finger 76 is mounted in an adjustable manner on the slide 72. However, this device adjustment has not been shown in the drawings, for the sake of simplification.

Figure 14 shows the operation of this front stop under normal conditions for which the friction between the shoe sole and the pad 78 is low. The jaw 64 swings over one of the knives 63 by drawing back the tie rod 65, which causes the series of springs 66, 67 to be compressed, which behave like a single spring.

Figure 13 shows the operation of this front stop when the shoe is dirty or in bad condition so that it drives the plates 78 and 77 in its movement. The cam 75 formed on the latter acts on the follower member 76 causing the slide 72 and its vertical extension 73 to recede. Or l the inclination of the ramp 75 has been defined in such a way that the displacement of the slider 72 is greater than that of the tie rod 65 whatever the path of release of the boot. As a result, the spring 67 compresses strongly, while the spring 66 relaxes. The shoe retaining hardness is therefore exerted only by the relaxed spring 66, consequently with a force less than the force preset initially.

It goes without saying that the front stop of the invention can undergo various modifications without departing from the scope of the invention. Thus one could for example provide a shoe support device constituted by a series of sole support rollers, the rotation of which would control the lowering of hardness of the elastic system. The invention could also be applied to front stops whose jaw is formed of two independent arms.

Claims (6)

1. Toe abutment for safety ski binding, comprising a jaw unit (4; 44; 64) for retaining the ski boot (6; 42; 62), said jaw unit being pivotally mounted on a pin (5; 31; 70) perpendicular to the plane of the ski (2) and in cooperating relation with a resilient device (22, 24; 37, 34; 66, 67) having pre-adjusted stiffness for acting in opposition to the pivotal displacement of the ski boot about its pivot-pin (5; 31; 70) as well as a system (9, 10, 12; 46, 47; 74, 77) for supporting the front portion of the ski boot (6; 42; 62) comprising a member (12; 47; 77) which is capable of moving both with respect to the ski (2) and with respect to the jaw unit (4; 44; 64) and can be caused to move as a result of transverse displacement of the ski boot, characterized in that this movable member (12; 47; 77) is independent of the jaw unit (4; 44; 64) and that provision is made for a connecting slide (18; 55; 72) between the resilient device (22, 24; 37, 34; 66, 67) and the movable member (12; 47; 77), this slide being actuated by this movable member by means of ramps or cams (16; 53; 75) and being capable of reducing the stiffness of retention of the ski boot (6; 42; 62) resulting from the action of the resilient device aforesaid, when the movable member is displaced laterally by this latter.

2. Toe abutment in accordance with claim 1,. characterized in that the connecting slide (18; 55; 72) is guided within the base of the abutment member along the axis of the ski, and this slide produces action on the resilient device (22, 24; 37, 34; 66, 67) when it is in turn displaced by the movable member (12, 47, 77) placed beneath the ski boot (6).

3. Toe abutment in accordance with claim 2, characterized in that a cam (16, 75) is formed on the movable member (77) or on the slide (18) and cooperates with an element which is coupled to the slide or to the movable member as the case may be, for example a roller (15) or a stud (76), in order to ensure transmission of motion between the movable member (12, 77) and the slide (18, 72).

4. Toe abutment in accordance with claim 2, characterized in that transmission of motion between the movable member (47) and the slide (55) is obtained by means of force reduction levers (51 a, 51 b) rotatably mounted on pins at right angles to the ski and provided with ramps (53a, 53b) which cooperate with the movable member in such a manner as to ensure that the displacement of this latter in sliding motion on either of the two ramps (53a, 53b) produces a pivotal displacement of the corresponding lever (51 a, 51 b) which then displaces the slide (55).

5. Toe abutment in accordance with either of claims 1 or 2, characterized in that the movable member (12; 47; 77) is a plate placed parallel to the plane of the ski and guided so as to move in an approximately transverse direction with respect to the ski and preferably in a circular arc, the centre of which corresponds to the axis of pivotal displacement of the ski boot (6; 42; 62) within the ski binding.

6. Toe abutment in accordance with claim 2, characterized in that the slide (55) carries a bearing member (56) in the form of a vertical extension for the toe end of the sole.

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