EP0370948B1 - Inner shoe for a ski boot - Google Patents

Abstract

Lining (1) for ski boot, comprising at least one part made of relatively rigid compact synthetic material, lined on the inside with a synthetic material of lower hardness (4). The relatively rigid synthetic material has at least one cutout (5, 6) of closed outline so that the hard part adapts better to the morphology of the foot or of the ankle. <IMAGE>

Description

The present invention relates to an inner lining for a ski boot, having parts of relatively rigid compact synthetic material lined, inside, with a synthetic material of lesser hardness. The term “interior trim” means any part intended to garnish the bare shell, such as liner, tongue, anterior and posterior spoilers, edges, etc.

This type of lining is commonly used in ski boots made of injected synthetic material. In these linings, in particular the slippers, the compact synthetic material does not always have the flexibility necessary for a perfect adaptation of the slipper to the shape of the foot or of the ankle and to deform during flexion of the leg. This is particularly the case of the tongue intended to distribute the tightening pressure exerted by the buckles of the shoe on the instep and on the anterior part of the lower leg. To this end, the tongue has a relatively hard and rigid outer part and an inner lining made up of at least one elastic compressible layer. The known tongues do not, however, have a truly anatomical shape, but simply a rounded shape more or less matching the shape of the instep and the leg. For skiing, the boot must be tight on the foot and the clamping pressure is not generally distributed uniformly on the foot by the tongue, but on the contrary, localized compression zones are created, precisely in due to the poor adaptation of the shape of the tongue to the instep and the leg, these compression zones localized being unpleasant and can become painful after a certain time. These remarks also apply to the other parts of the packing made of relatively hard plastic.

It would certainly be possible to adapt the shape of the tongue and the other parts concerned to the morphology of the foot, but taking into account the morphological differences between individuals, adaptation should be done individually for each individual, which does not is practically not achievable.

Also, with regard to the tongue, when flexing the foot forward, the proper extensor muscle of the big toe tends to move forward and upward. However, if it is already compressed by the tightening of the shoe, it is impossible to carry out this natural displacement. This also applies to other muscles and tendons such as the Achilles tendon, for example.

In order to allow the ankle to flex while ensuring a good hold of the foot, it has been proposed to split the tongue into two parts connected by a flexible strip, one extending over the foot and the other over the leg, that is to say the tibia, but each part is itself rigid and does not solve the problem of localized pressures (US-A-4,534,122)

The object of the present invention is to produce an interior lining, the compact plastic parts of which adapt automatically, to the greatest possible extent, to the shape of the wearer's foot or ankle and do little to prevent deformation. when bending the leg.

The interior trim according to the invention is characterized in that at least one of the relatively rigid plastic parts has at least one cut of closed contour.

On the tongue of the liner, for example, the cut can be unique, that is to say, extend over both the instep and on the part of the tongue located above the instep, or in two parts, one located on the instep and the other on the part of the tongue located above the instep.

The cut, respectively the cutouts ensures a good adaptation of the tongue to the morphology of the foot. The shape of the upper part of the cut takes into account that the lower front part of the leg is not symmetrical. The inner part of the leg consists essentially of the tibia, while the muscles occupy the outer part. The tongue of the boot according to the invention distributes the pressure more evenly, because the tongue is always in uniform contact with the surface of the tibia. The transverse rigidity of the tongue is reduced and the pressure and lateral friction, caused by the edges of the known tongues which tend to sink into the calf, particularly inside the leg, are eliminated.

The part of the cut, respectively the cut of the tongue, located on the instep reduces the rigidity of the tongue at this location and allows the clean extensor muscles of the big toe to lift without encountering too much resistance. This part of the cut is preferably offset laterally towards the inside of the foot so that the middle of the cut is located on the proper extensor muscle of the big toe.

The accompanying drawing shows, by way of example, three embodiments of the invention.

Figure 1 shows a boot according to a first embodiment.

FIG. 2 is a front view of the tongue of the bootie of FIG. 1.

Figure 3 is a perspective view of a second embodiment of the tongue can be used in the boot of Figure 1 in place of the tongue shown.

FIG. 4 is a view in longitudinal median section of the tongue shown in FIG. 3.

Figure 5 shows the tongue of Figure 3 without its lining.

Figure 6 shows the foam lining of this same tongue.

FIG. 7 is a side view of the lining shown in FIG. 6.

Figure 8 shows a third embodiment of the tongue.

Figure 1 shows a boot of known shape, in the form of a boot having, at the front, a deep indentation 1 extending as far as the instep. This boot can be made of felt or synthetic material coated with a soft lining. At a point 2 located on the instep, inside the boot, is fixed a tongue 3 made of relatively hard and rigid synthetic material and thermoformed in the form of a horse saddle so as to approximately adapt to the shape of the instep. This tongue 3 is lined internally by a synthetic foam 4 which appears through two cutouts 5 and 6 of the tongue 3. The cutout 5 has a first part 5a extending transversely a little below the upper edge of the tongue 3, this part 5a being followed by a part 5b extending longitudinally on the left side of the tongue - or of the wearer, the booties shown being the booties of the right foot - that is to say on the inside of the leg, substantially parallel to the lateral edge of the tongue 3. The lower end of the part 5b is just above the instep. The cutout 6 is on the other hand oval in shape and extends over the instep, so that it extends substantially equally on either side of the proper extensor muscle of the big toe. In cuts 5 and 6, the resistance to deformation of the foam 4 is increased by transverse grooves 7 to 12 obtained by hot crushing of the material 4. The tongue 3 is sewn at point 2 of the liner by its end 13. The tongue 3 closes the notch 1 when the shoe is closed.

When tightening the shoe, the part 5b of the cutout 5 allows the right part, in the drawing, of the tongue to better adapt to the tibia which is flush with the inside of the leg, by eliminating the localized compression zone. due to an inadequacy of the curvature of the tongue to the shape of the tibia which has an edge followed by an approximately flat surface. The upper part 3a of the tongue 3 located above the part 5a of the cutout 5 forms a transverse strip which can deform differently from the rest of the tongue. During the flexion of the leg, that is to say the support of the shin on the tongue, this part 3a can flex, both forwards and downwards, so that the upper edge of the tongue 3 no longer exerts painful compression on the tibia. The part 3b of the tongue extending between the lateral edge and the part 5b of the cutout 5 is also in the form of a strip capable of deforming relatively easily. The L-shaped shape of the cutout 5 ensures good adaptation of the tongue 3 to tightening and bending while retaining a resistant part to receive the pressure of the tightening loops. This resistant part is essentially constituted by the zone 3c located inside the L. Such a combination of rigidity and flexibility characteristics could not have been obtained by a median longitudinal cut or by two cuts parallel to the axis of the tongue.

The effect of cutout 6 is twofold. In the absence of such a cut, the bending of the tongue 3 above the instep has the effect of reducing the transverse curvature of the tongue on the instep, which has the effect of compress the clean extensor muscle of the big toe. The presence of the cutout 6 significantly reduces this effect. On the other hand, the cutout 6 allows the proper extensor muscle of the big toe to lift up while meeting only the weak resistance of the foam 4.

The tongue 3 'shown in FIGS. 1 to 7 differs from the tongue 3 only in the shape of the cutout. The tongue 3 'has a single cutout 14 extending over the greater part of the length of the tongue. This cutout 14 also has an upper part 14a extending transversely and parallel to the upper edge of the tongue 3 'like the part 5a of the cutout 5, this part 14a being followed by a part 14b extending laterally and substantially parallel to the inner lateral edge of the tongue, like the part 14b, and connected to a part 14c of oval shape, like the cutout 6 of the first embodiment, extending over the instep, by a part having firstly an enlargement 14d corresponding to the flexion zone of the foot, followed by a narrowing 14e. This tongue 3 'has better flexibility in bending than the tongue 3 of the first embodiment.

Figures 3 to 7 illustrate more fully the constitution of the tongue. This constitution is also valid for the tongue 3 of the first embodiment. The edge of the cut is sewn to the lining 4 of the tongue by a seam 15. The foam 4 is itself doubled by a thick non-woven, soft textile layer, 16, lined internally with a fabric 17. We find on the tongue 3 'the transverse crushing 7', 8 ', 9' etc. corresponding to transverse crushing 7, 8, 9 etc.

The tongue 3 'and the foam 4 are shown separately in FIGS. 5 to 7.

The shape and dimensions of the cutout, respectively of the cutouts shown, may of course differ slightly from the shapes and dimensions shown. The main thing is to respect the layout and orientation claimed.

Instead of synthetic foam, it is possible to use other thermoformable materials to make the lining of the tongue. The only condition is that this material is substantially less hard than the material of the tongue.

FIG. 8 illustrates another example of execution. The material of the tongue 3 is, for example, the same as in the previous embodiments. This tongue 3 has two cutouts 22 and 23 similar to the cutouts 5 and 6 of Figures 1 and 2, but of a slightly different shape. This tongue is lined with a thermoformable synthetic material 24 which is substantially less hard than the tongue. This material 24 is given the desired shape and thickness by thermoforming, then the part obtained is fixed to the tongue 3 by sewing or by high frequency welding.

By using, for the material 24, a material compatible with that of the tongue, for example of the same family, but less hard, the material 24 can be fixed to the tongue by overmolding or over-injection. Such a tongue is more resistant; its manufacturing cost is reduced; its aesthetic appearance is improved and it is possible to obtain tongues of different aspects.

Cutouts could also be provided in the rear part 18 of the bootie, as well as in the upper edges 19, 20 and 21 projecting from the shell of the shoe and resting on sensitive parts of the ankle and the bottom of the calf.

In rear entry shoes, the rear part of the boot is replaced by a rear spoiler and the tongue by a front spoiler. These spoilers can be fitted with suitable cutouts like the tongue 3.

Claims (11)

1. Inner lining for a ski boot, possessing parts made from a relatively hard, compact synthetic material lined, on the inside, with a synthetic material of lesser hardness (4; 24), characterized by the fact that at least one of the parts made from a relatively hard synthetic material (3) possesses at least one cut-out (5, 6; 14; 22, 23) of closed contour.
2. The inner lining as claimed in claim 1, characterized by the fact that the synthetic material of lesser hardness is a foam (4).
3. The inner lining as claimed in claim 1 or 2, characterized by the fact that the synthetic material of lesser hardness is fixed to the hard synthetic material by stitching.
4. The inner lining as claimed in claim 1 or 2, characterized by the fact that the synthetic material of lesser hardness is fixed to the hard synthetic material by welding.
5. The inner lining as claimed in claim 1, characterized by the fact that the synthetic material of lesser hard is molded over the hard synthetic material.
6. The lining as claimed in one of the claims 1 to 5, more particularly a liner possessing, at the front, a deep scalloping (1) covered, on the inside, by a tongue (3) of relatively rigid compact synthetic material lined, on the inside, with at least one layer of synthetic foam of lesser hardness (4), said tongue being fixed by its lower end in a manner such as to cover the instep and the front part of the bottom of the leg, characterized by the fact that the relatively rigid synthetic material of the tongue possesses at least one cut-out (5, 6; 14) of closed contour extending transversely in the upper part of the tongue, substantially longitudinally and laterally over at least part of the height of the tongue, on the inner side of the leg and over at least part of the instep.
7. The liner as claimed in claim 6, characterized by the fact that the tongue possesses a single cut-out (14).
8. The liner as claimed in claim 6, characterized by the fact that the tongue possesses two cut-outs, one (5) extending over the part situated above the instep and the other (6) over the instep.
9. The liner as claimed in one of the claims 6 to 8, characterized by the fact that the middle of the cut-out (6), or the part of the cut-out (14) situated over the instep, is situated on the long extensal muscle of the big toe.
10. The liner as claimed in one of the claims 6 to 9, characterized by the fact that the synthetic foam (4) situated in the cut-out or cut-outs possesses transverse zones compressed by thermoforming.
11. The liner as claimed in claim 7, characterized by the fact that the cut-out (14) of the tongue possesses a widened portion (14d) at the point of its flexion and in front a narrowed portion (14e) ensuring the continuity of the cut-out on the instep.

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