FR2644044A1

FR2644044A1 - Inner bootee for a sports shoe and method for manufacturing such a bootee

Info

Publication number: FR2644044A1
Application number: FR8903024A
Authority: FR
Inventors: Didier Baer
Original assignee: Recticel NV SA
Current assignee: Recticel NV SA
Priority date: 1989-03-08
Filing date: 1989-03-08
Publication date: 1990-09-14

Abstract

Inner bootee for a sports shoe, particularly a ski boot. This bootee consists of a foam material whose density can vary according to the zones of the bootee, the zones of comfort having a density which is less than the zones for the transmission of forces. Method for manufacturing a bootee with a virtually constant thickness and a density which can vary according to the zones of the bootee.

Description

Chausson interne de chaussure de sport et procédé de fabrication d'un tel chausson
Il est connu, en particulier pour les chaussures de ski, de réaliser une chaussure de sport en deux parties : un chausson en une matière relativement souple et élastique et une coquille externe rigide et résistante.Internal shoe liner and method of manufacturing such a liner
It is known, in particular for ski boots, to produce a sports shoe in two parts: a boot in a relatively flexible and elastic material and a rigid and resistant external shell.

La fabrication du chausson se heurte à des impératifs contradictoire6, car il faut qu'il assure à la fois le confort du pied et un bon maintien du pied pour permettre, par exemple dans le cas du ski, une bonne transmission des efforts du pied au ski, pour que le skieur ait un bon contrôle de son ski. Le bon confort du pied du skieur est obtenu avec un matériau mou, mais alors la transmission des efforts est mauvaise. Si le chausson est en matériau dur ou relativement dur, on obtient une bonne transmission des efforts, mais au détriment du confort. The manufacture of the liner comes up against contradictory requirements6, because it must ensure both comfort of the foot and good support of the foot to allow, for example in the case of skiing, a good transmission of the forces from the foot to the ski, so that the skier has good control of his ski. The good comfort of the skier's foot is obtained with a soft material, but then the transmission of the forces is poor. If the liner is made of hard or relatively hard material, good transmission of forces is obtained, but at the expense of comfort.

On a déjà proposé, pour contourner cette difficulté, de réaliser le chausson par assemblage de matériaux différents : cette solution est satisfaisante, mais très onéreuse. It has already been proposed, to circumvent this difficulty, to produce the liner by assembling different materials: this solution is satisfactory, but very expensive.

La présente invention a pour objet de solutionner ce problème, en permettant de réaliser, au moyen d'un seul matériau, un chausson dont la dureté est variable et progressive selon les zones du chausson. The object of the present invention is to solve this problem, by making it possible, using a single material, to produce a liner whose hardness is variable and progressive according to the zones of the liner.

Le chausson selon la présente invention est caractérisé par le fait qu'11 est constitué par un matériau en mousse, dont la densité est variable selon les zones du chausson, les zones de confort ayant une densité moindre que les zones de transmission d'efforts. The liner according to the present invention is characterized in that it is made of a foam material, the density of which varies according to the zones of the liner, the comfort zones having a lower density than the zones for transmitting forces.

Le procédé selon l'invention consiste à fabriquer un chausson en matériau en mousse, l'épaisseur de la mousse étant variable selon les zones, et plus forte dans les zones à transmission d'efforts, puis à densifier, par compression à chaud, les zones plus épaisses, de façon à obtenir un produit fini dont l'épaisseur est pratiquement constante, mais dont la densité, et donc la dureté, est variable d'une zone à l'autre du chausson. The method according to the invention consists in manufacturing a liner of foam material, the thickness of the foam being variable according to the zones, and greater in the zones with transmission of forces, then in densifying, by hot compression, the thicker zones, so as to obtain a finished product whose thickness is practically constant, but whose density, and therefore hardness, is variable from one zone to another of the liner.

Selon ce procédé, on opère selon les phases successives suivantes
a. on dispose une chaussette sur un poinçon dont la forme correspond à la forme d'un pied;
b. on place ce poinçon ainsi recouvert dans un moule ou matrice dont la paroi interne est située à une certaine distance du poinçon, cette distance étant variable selon les zones du poinçon;
c. on injecte une mousse alvéolaire dans l'interstice compris entre la matrice et le poinçon et, après prise de la mousse on démoule par ouverture de la matrice;
d.On place ensuite le poinçon recouvert de l'ébauche de chausson, dont l'épaisseur varie suivant les zones, dans une deuxième matrice dont la paroi est pratiquement à distance constante du poinçon, cette distance correspondant, de préférence, à l'épaisseur normale du chausson dans les zones de confort, de sorte que la mousse est comprimée dans les zones de surépai sseur;
e. on chauffe la matrice et, éventuellement, le poinçon, pour obtenir une densification des zones où la mousse est comprimée;
f. on ouvre la matrice et on retire le chausson du poinçon.According to this process, one operates according to the following successive phases
at. a sock is placed on a punch whose shape corresponds to the shape of a foot;
b. this punch thus covered is placed in a mold or matrix whose internal wall is located at a certain distance from the punch, this distance being variable according to the zones of the punch;
vs. an alveolar foam is injected into the interstice between the die and the punch and, after setting of the foam, it is removed from the mold by opening the die;
d.We then place the punch covered with the boot liner, the thickness of which varies according to the zones, in a second die whose wall is practically at constant distance from the punch, this distance preferably corresponding to the thickness normal of the liner in the comfort zones, so that the foam is compressed in the areas of excess thickness;
e. the matrix and, optionally, the punch are heated, to obtain a densification of the zones where the foam is compressed;
f. we open the matrix and remove the liner from the punch.

On obtient ainsi un chausson en mousse alvéolaire, dont l'épaisseur est pratiquement constante, mais dont la densité est progressivement variable d'un endroit à l'autre, les zones de moindre densité étant les zones "molles" ou le confort est recherché et les zones de plus forte densité étant les zones "dures", où le bon maintien du pied est recherché. A cellular foam liner is thus obtained, the thickness of which is practically constant, but the density of which is progressively variable from one place to another, the areas of lower density being the "soft" areas where comfort is sought and the areas of highest density being the "hard" areas, where good support of the foot is sought.

Le chauffage de la surface du chausson permet en outre d'obtenir la formation en surface d'une pellicule qui améliore l'étanchéité dudit chausson. Heating the surface of the boot also makes it possible to obtain the formation on the surface of a film which improves the tightness of said boot.

On peut également, selon la présente invention, colorer la mousse avantl'injection, ce qui a pour résultat que les zones densifiées apparaissent nettement, leur coloration étant d'autant plus intensifiée que la densification est plus importante. It is also possible, according to the present invention, to color the foam before injection, which has the result that the densified zones appear clearly, their coloration being all the more intensified as the densification is greater.

Il est bien évident que la densification ne dépendant que de l'importance de l'interstice ménagé entre le poinçon et la paroi interne du premier moule ou moule d'injection, on peut moduler b volonté l'importance de la surépaisseur selon les zones et donc, moduler à volonté la densification et donc la variation ae la dureté du chausson selon les zones. It is obvious that the densification depends only on the size of the gap formed between the punch and the internal wall of the first mold or injection mold, it is possible to modulate the size of the additional thickness according to the zones and therefore, modulate at will the densification and therefore the variation in the hardness of the liner according to the zones.

De préférence, pour le confort du pied, on dispose à l'intérieur du chausson un tissu ou analogue; c'est-à-dire un matériau répondant aux exigences de confort, de facilité de glissement ou pied dans le chausson et de résistance superficielle ; le matériau alvéolaire est une mousse en polyuréthane, mais cela n'est pas limitatif et la couche de matériau alvéolaire cOté chaussure est un film étanche ce qui signifie que ce film est une barrière à la progression de la mousse alvéolaire lors de l'opération d'injection et assurant la liaison de la chaussette avec cette dernière. Preferably, for the comfort of the foot, there is inside the liner a fabric or the like; that is to say a material meeting the requirements of comfort, ease of sliding or footing in the liner and surface resistance; the foam material is a polyurethane foam, but this is not limiting and the layer of foam material on the shoe side is a waterproof film which means that this film is a barrier to the progression of the foam during the operation of injection and ensuring the connection of the sock with the latter.

Ainsi, à titre d'exemple, la chaussette que l'on dispose sur le poinçon au début des opérations, peut etre constituée en un matériau composite constitué par une couche de tissu; une couche de mousse de polyurethane découpée et assemblée; un film étanche de polyester. Thus, by way of example, the sock which is placed on the punch at the start of the operations, can be made of a composite material constituted by a layer of fabric; a layer of cut and assembled polyurethane foam; a waterproof polyester film.

Claims

1. Internal boot of a sports shoe, in particular a ski boot, characterized in that it is made of a foam material, the density of which varies according to the areas of the boot, the comfort areas having a lower density than the force transmission zones.

2. A method of manufacturing a liner according to claim 1, according to which a liner is made of a cellular material, such as a foam, the thickness of the material of which the liner is made being more tortuous in the transmission zones. 'efforts only in comfort zones; then the areas of excess thickness are densified by hot compression, so as to obtain a finished product whose thickness is practically constant, but whose density, and therefore the hardness, is variable from one area to the other of said slipper.

The manufacturing method according to claim 2, wherein

at. there is a sock on a punch whose shape corresooni the shape of a foot;

b. this punch thus covered is placed in a mold or matrix whose internal wall is located at a certain distance or punch, this distance being variable according to the zones of the punch;

vs. injecting a foam into the gap between the die and the punch and, after setting the foam, it is removed by opening the die;

d. the punch is then placed covered with the boot liner, the thickness of which varies according to the zones, in a second die, the wall of which is practically at constant distance from the punch, this distance preferably corresponding to the normal thickness liner in the comfort zones, so that the foam is compressed in the over-thickness zones;

e. the matrix and, optionally, the punch are heated, to obtain a densification of the zones where the foam is compressed;

f. we open the matrix and remove the liner from the punch.

4. The method of claim 3, wherein the foam is colored before the injection pnase, so that the finished product has a color varying according to its density.

5. Method according to any one of claims 2 to 4, according to which the sock is made of a composite material, constituted by a layer of fabric or the like; an intermediate layer of cellular material; a coating barrier to the progression of the injected foam and ensuring a good bond with it.