EP0677308A1 - Binding element for holding a boot in position on a sliding board - Google Patents

Abstract

The binding has a body with a base (21) made in plastics material. This is reinforced by two side plates (23,24) joined by an upper plate (29) which are made in metal. These fit over the body and extend between the axis of articulation of the binding and the runners (36). The lower part of the reinforcing has horizontal edges (31,32) which are engaged along the lateral edges of the runner. The horizontal edges of the side plates (33,34) are covered with anti-friction material and extends continuously from the runners. <IMAGE>

Description

The invention relates to a fastening element for keeping a shoe in abutment on a gliding board, in particular on an alpine ski.

More specifically, the invention relates to a fastening element having a body which is slidably mounted along a slide secured to the ski.

Many fasteners of this type exist on the market, or are known, for example from French patent applications published under the numbers 2 338 060 and 2 494 591.

Usually, these fixing elements comprise a fixing body mounted to slide along a longitudinal slide, by means of sliding shoes engaged on the longitudinal edges of the slide which prevent any relative vertical movement between the body and the slide. They also include a shoe retaining jaw which is articulated on the binding body so as to be able to switch between a shoe retaining position and a release position.

Generally, a locking member guided in the body and pushed back by a spring resiliently recalls the retaining jaw towards one or the other of these two positions which are stable positions.

In addition, a voluntary release lever articulated around a transverse axis carried by the body or the locking member makes it possible to voluntarily move the jaw from its retaining position to its release position.

These various elements exert stresses on the body which depend on the stiffness of the return spring and on the pre-stress adjustment applied to it. The stiffness of the spring and its pretension define the hardness of the fastening element, that is to say the intensity of the force which must be applied to the jaw to cause it to pass towards the release position. This intensity is also called the trigger value of the fixing element.

Fastening elements with high hardness generally have a body made of metal, for example an aluminum alloy. Such a body resists well the constraints to which it is subjected. However, its cost is high and its manufacture requires relatively complex assembly operations.

Thus, for the lower hardness fasteners, molded plastic bodies are used. Such bodies have a lower cost price and their manufacture is simple.

However, for high hardness settings, elastic deformations of the body have been found which generate friction between the different moving elements. These deformations disturb the operation of the fastening element and increase the dispersion of the trigger values.

In addition, it may happen that certain particularly high stresses irreversibly degrade the body over time, for example by breaks.

One of the aims of the invention is to provide a fastening element whose body is made essentially of plastic, but has a higher resistance to the stresses to which it is subjected than the bodies currently known.

Another object is to provide a fastening element whose body is more resistant, therefore less sensitive to elastic deformations.

Another object of the invention is to provide a fastening element whose body is simple to produce and has a relatively low cost.

These aims and other aims which will appear during the description which follows are achieved by the fastening element according to the invention as defined below.

• un corps de fixation monté coulissant le long d'une glissière longitudinale, par l'intermédiaire de patins de coulissement engagés sur les bords longitudinaux de la glissière et interdisant tout mouvement vertical relatif entre le corps et la glissière,
• une mâchoire de retenue de la chaussure articulée sur le corps de fixation de façon à pouvoir basculer entre une position de retenue de la chaussure et une position de libération.

The fixing element comprises:

• a fixing body mounted sliding along a longitudinal slide, by means of sliding shoes engaged on the longitudinal edges of the slide and preventing any relative vertical movement between the body and the slide,
• a shoe retaining jaw articulated on the binding body so as to be able to switch between a shoe retaining position and a release position.

It is characterized by the fact that the body has a base made of a relatively weak material, and that it laterally presents two reinforcing flanges which extend at least between the axis of articulation of the jaw and the level of the sliding runners.

The reinforcement flanges channel the stresses generated by the axis of articulation of the jaw and, where appropriate, the axis of articulation of the release lever towards the slide, where these forces are taken up. Therefore, the part of the body made of plastic material is only subjected to low stresses, and overall, the body can withstand higher stresses than traditional bodies made entirely of plastic material. They can even withstand stresses of the same order as bodies made of metal.

In addition, as will appear in the description which follows, the addition of the flanges does not complicate the manufacture of the body beyond measure.

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

Figure 1 illustrates the prior art, and shows a side view and partial section of a rear fixing element.

2 shows a side view of the body of a fastening element according to a first non-limiting embodiment of the invention.

Figure 3 shows the body of Figure 2 in section through a vertical and transverse plane.

FIG. 4 is an exploded perspective view of the body of FIGS. 2 and 3.

Figures 5 and 6 are figures similar to Figure 3 and show alternative embodiments of the invention.

Figure 1 illustrates the prior art. It represents a rear fastening element 1 comprising a body 2 slidably mounted along a base plate 3 which is intended to be assembled to the ski, by any suitable means, for example by screwing.

As shown schematically in Figure 1, the base plate 3 externally comprises a covering part 4, made for example of plastic. Inside the covering part there is a slide 5, which, in the example shown has the shape of a "C" lying open up. The body 2 is connected to the slide 5 by pads 6 which are engaged in the lateral folds of the slide. This assembly allows a translational movement of the body along the direction defined by the slide, but hinders any relative movement in a perpendicular direction, in particular vertical.

The body 2 carries a jaw 7 which is articulated around a transverse axis 8. The jaw allows the retention of the shoe.

On its rear face, the jaw carries a succession of two ramps 9 and 10. A piston 11, guided in translation in the body, is pushed against one or the other of the ramps 9 and 10 by a spring 12, the initial stress is adjustable by means of a threaded plug 13 which is screwed into the body. By its compression, the spring resists elastically the movement of the jaw.

The two ramps 9 and 10 of the jaw define its two stable positions, that is to say the low position for retaining the shoe, and the high position for releasing the shoe. It is the spring 12, by means of the piston 11 which recalls the jaw in one or the other of these positions. The two ramps are separated by an edge 14. The edge 14 forms the boundary between the two positions towards which the jaw is returned elastically. When the piston crosses the edge 14, the spring 12 is in a state of maximum compression. The stiffness of the spring and the prestress applied to it by the plug 13 determine the return force of the spring, and therefore the hardness of the fastening element, to which corresponds a trigger value, i.e. a value of the force to be applied to the jaw to drive it from its holding position to its release position.

A release lever 15 makes it possible to open the jaw voluntarily. The lever has a large operating arm 16 which extends from bottom to top and from front to back above the body.

In the illustrated embodiment, the lever is articulated in rotation about an axis 18 carried by the piston 11. In its lower part, it has two small parallel arms 17, slightly curved, which form a sort of fork and which take support under two lateral cheeks 19 at the rear face of the jaw.

When the lever is actuated to open the jaw, it bears on its axis 18 to raise the jaw by means of its small arms 20.

Raising makes the jaw describe the same circuit as during an accidental opening.

Naturally, this construction is not limiting, and there are many other constructions, in particular constructions which would employ an articulated rocker in place of the spring, or constructions where the jaw and the lever are carried by the body around 'a common axis. This construction highlights the fact that the body 2 is subjected to various stresses originating in particular from the hinge axis 8 of the jaw, from the hinge axis 18 of the lever, of the piston, and of the spring.

According to the prior art, the body is made of plastic, by molding, for small or medium trigger values. On the other hand, for high trigger values, the body of the fixing element is made of metal, for example an aluminum alloy.

Figures 2 and 3 illustrate a first embodiment of the invention. They represent a body 20 whose shape and dimensions are for example the same as those of the previous body 2 or of an existing body.

The body 20 has a base 21 made of plastic, for example by molding. In known manner, the base 21 has a longitudinal recess provided for receiving the locking member, for example a piston or a rocker, and the return spring of this member.

A reinforcement 22 in the form of an inverted "U" also overlaps the base 21 of the body. The reinforcement is made of resistant material, for example metal, steel, aluminum alloy or composite material. In particular, the reinforcement is produced from a cut sheet then shaped by folding.

In the embodiment of FIGS. 2 to 4, the reinforcement is attached to the base 21. According to another assembly technique where the base of the body is produced by molding, the reinforcement could be placed at the bottom of the mold, and the base body could then be injected into the mold.

The reinforcement laterally has two flanges 23 and 24 joined in their upper part by a bridging 26. The flanges and the bridging internally match the outer contour of the body. Preferably, as shown in FIG. 4, the wall of the base has a decrease in thickness in the area of the reinforcement, which corresponds to the thickness of the reinforcement, so that overall, the outer surfaces of the reinforcement and from the base of the body are in continuous extension of each other.

The flanges extend at least from the region of the axis of articulation of the jaw, downwards, to the connecting pads with the slide. Preferably, the flanges also cover the area of the axis of articulation of the release lever, if the latter is distinct from the axis of the jaw.

For this purpose, the flanges have openings 27, 28, for the passage of the axis of the jaw, and 29, 30, for the passage of the axis of the heaving lever. These openings are opposite the corresponding openings in the base. Their dimensions are preferably equal to or very slightly greater than the dimensions of the corresponding openings in the body. In this way, a stress exerted by an axis is first transmitted to the base of the body, that is to say the plastic part, which deforms until the flanges take over and provide the reaction to these constraints. This gives a gradual transfer of forces.

Preferably also, the reinforcement extends only in the front part of the body.

The flanges 23 and 24 have in their lower part a rim, respectively 31, 32, oriented towards the outside parallel to a horizontal plane. As can be seen in FIG. 3, the flanges 31 and 32 are engaged in the lateral folds 35 and 36 of the slide 37.

Thus, the flanges 23 and 24 of the reinforcement 22 relieve the front part of the body of at least part of the stresses exerted by the axis of articulation of the jaw in the area of the openings 27 and 28, if necessary the stresses exerted by the axis of articulation of the lever in the area of the openings 29 and 30. They channel these constraints towards the slide where they are taken up by the folds 35, 36, then transmitted to the ski. The flanges 31 and 32 also provide longitudinal guidance of the body along its slide.

The rear part of the body is mainly subject to the reaction of the spring. However, taking into account the general shape of this part of the body, the general direction and the intensity of these stresses, these can be supported by the base 21 of the body, without requiring any particular reinforcement.

Preferably, the flanges 31 and 32 of the flanges are provided with sliding linings, in order to facilitate the translation of the body along the slide. These linings are for example constituted by a coating of anti-friction material such as polytetraflurethylene.

According to another embodiment visible in Figures 3 and 4, these linings are constituted by a segment 33, 34, which continuously extends the pads which run along the base 21 of the body. Only the shoe 36 is visible in FIG. 4.

The segments 33 and 34 preferably have an inverted "L" shape in section, so as to cover the edges 31 and 32 on their upper face and their outer vertical face.

Between the segments 33 and 34 and the rest of the base of the body is a slot 37, 38, open on the front of the body. The slot has dimensions corresponding to those of the flanges 23 and 24, in order to allow engagement from the front of the reinforcement on the base of the body and its maintenance. The flanges are engaged in the slots 37 and 38, and their flange 31, 32, are received in the recess defined by the segments 33 and 34. To facilitate the maintenance of the reinforcement, its flanges could be slightly closed at rest, so that once in position on the base of the body they produce a pinch.

We could also make the segments 33 and 34 slightly divergent, depending on whether they have a backlash function between the body and its slide. Any other appropriate means, in particular local deformations of the segments, may also be suitable for this purpose.

Preferably, the upper bridging 26 of the reinforcement is reinforced by a rib 40 obtained by local deformation. This rib extends in a main transverse direction. Over its length and in section, it also has any suitable shape.

In addition, the flanges preferably have under the openings 27 and 28 an over-thickness pad, respectively 41, 42. These pads locate the area of friction between the jaw and the body, or between the lever and the body, and keep the cheeks of the jaw or lever away from the body. According to an alternative embodiment, the pellets are made on the side walls of the base and pass through orifices made in the flanges.

According to another variant, the flanges have an orifice in which inserted inserts are placed. The pellets can be made of metal or plastic.

FIG. 5 illustrates an alternative embodiment. According to this variant, the reinforcement has two independent puddles 43 and 44. As in the previous case, the flanges extend from the area of the axis of articulation of the jaw, shown diagrammatically at 47, as far as the pads 49 and 50 of connection with the slide.

As can be seen in Figure 5, the flanges have approximately an "S" shape. Their upper part is fitted onto the external part of the base 48 of the body. Their lower part is fitted into the lower part of the base 48 of the body. Their middle part crosses an opening of the side walls of the body, respectively 45, 46. As in the previous case, preferably, the lower flanges 51, 52, the flanges are coated with an anti-friction lining which advantageously comes from the plastic wall at the base from the body. It would also be possible to overmold the edges 51 and 52.

This mounting method is advantageous because it ensures correct retention of the flanges along the body. However, it is not limiting, and two independent flanges could be used which are entirely fitted on the outer wall of the base of the body, that is to say flanges without bridging mounted in the manner of flanges 23 and 24. In this case, it would be the jaw and the lever which would ensure the maintenance of the flanges along the base of the body.

Other solutions are also possible. For example, the base of the body could be overmolded on the flanges, that is to say that the flanges could be partially or totally embedded in the side walls of the base 48 during its molding operation.

Figure 6 shows another variant. According to this variant, the slide in “C” lying and open upwards is replaced by a slide with lateral wings 55 and 56, and it is the lower part of the body 57 which is shaped as “C” lying and open towards the low to be engaged on the slide, allowing a translation of the body along the direction defined by the slide, and preventing any other movement.

As in the cases described above, the body 57 has a base 58 and a reinforcement 59 which conform to the external contour of the base.

In its lower part, the base has two pads which are engaged under the wings 55 and 56 of the slide. The skids are not visible in Figure 6.

The lateral flanges 61 and 62 of the reinforcement 59 have meanwhile in their lower part two horizontal flanges 63 and 64 which are engaged under the wings 55 and 56 of the slide. Preferably, the edges are coated with sliding linings. These linings are segments 65 and 66 which extend the pads of the base and which cover the edges 63 and 64 on a horizontal face and a vertical face.

The stresses that the axis of the jaw, shown diagrammatically at 68, transmits to the body are channeled by the flanges of the reinforcement 58 in the direction of the slide, so that the base of the body is relieved of these constraints.

The elastic deformations of the body are less significant than if the body were made entirely of plastic. Therefore, the friction which opposes the relative movement of the locking member, that is to say for example the piston or a rocker, is reduced, and the dispersion of the trigger values is lower.

The invention is not limited to the various embodiments which have been described, it encompasses variants, equivalents and other constructions as defined in the claims below.

In particular, the nature of the materials used for the body and the reinforcement is not limiting. The reinforcement could be made of a composite material, in particular a resin loaded with fibers.

The invention is also not limited to a rear fixing element. It applies to any fixing element whose body carries a retaining jaw.

Claims (10)

Fastening element for holding a shoe on a ski comprising: a fixing body (2) mounted to slide along a longitudinal slide (5), by means of sliding shoes (6) engaged on the longitudinal edges of the slide and preventing any relative vertical movement between the body and the slide, a shoe retaining jaw (7) articulated on the binding body so as to be able to switch between a shoe retaining position and a release position,
characterized by the fact that the body has a base (21, 48, 58) made of a relatively weak material, and that it has laterally two reinforcing flanges (23, 24, 43, 44, 61, 62) which s 'extend at least between the axis of articulation of the jaw and the level of the sliding pads. Element according to claim 1, characterized in that the reinforcing flanges (23, 24, 43, 44, 61, 62) have in their lower part horizontal flanges (31, 32, 51, 52, 63, 64) which are engaged along the side edges of the slide. Element according to claim 1, characterized in that the horizontal flanges (31, 32, 51, 52, 63, 64) of the flanges are coated with a sliding lining (33, 34, 49, 50, 65, 66) . Element according to claim 3, characterized in that each sliding pad is a segment which continuously extends the base pad (21, 48, 58). Element according to claim 4, characterized in that the shoe segments are slightly deformed relative to the rest of the shoe to make up for play. Element according to claim 1, characterized in that the two flanges (43, 44) are independent, and that they are engaged in form cooperation in the lateral flanks of the base (48) of the body. Element according to claim 1, characterized in that the upper part of the two flanges (23, 24) is joined continuously by a bridging (26). Element according to claim 6, characterized in that the bridging (26) is locally reinforced by a rib (40). Element according to claim 7, characterized in that before their engagement on the base of the body, the reinforcing flanges (23, 24) are slightly closed. Element according to any one of the preceding claims, characterized in that the base (21) of the body has a reduction in thickness in the region of the reinforcement (22).

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