FR2550424A1 - Improved sports shoe and resilient stabilisation device for a shoe of this type - Google Patents

Abstract

The said shoe 40 comprises an upper 41, at least one sole 43 secured to this upper, as well as a shock-absorbing material, 44, 45 inserted between the said sole and the foot of the wearer. A stabiliser 30 with a high modulus of elasticity is inserted between the foot of the wearer and the shock-absorbing material 44, 45 over which it lies. This stabiliser 30, which is thin, light and has a high modulus of elasticity, can flex without permanent deformation when a force giving rise to a bending stress is imposed on it and can then resume its initial configuration when the said force ceases. This stabiliser 30 gives back, to the wearer of the shoe 40, the energy which it has absorbed and stored. Application particularly to shoes for sports played on courts.

Description

 The present invention relates to moderating and stabilizing devices for shoes and, more particularly, to an improved device for elastic moderation and stabilization which, by elastic deformation, absorbed, redistributes and stores energy from loads and d localized efforts, then restores this energy in a form useful to the user when the effort ceases. It also results in better comfort, support and stability of the foot and the lower part of the leg.

 The prior art has already proposed numerous shoes in which there are provided inserted members and support elements, mainly with the aim of ensuring comfortable support for the human foot. For example, US Pat. No. 3,120,712 (Menken) describes an embodiment of a shoe comprising a bladder filled to a pressure of about 2.04 bar. A steel plate is placed on the bladder so as to confine it and, under a pressure of 2.04 bars, this plate must withstand and control a force of 2664 N and, therefore, it must be extremely rigid and not bend.

 US Pat. No. 2,237,190 (Mc Leod) describes a shoe comprising support elements made of an elastic material, these support elements being undulated transversely and thus being rigid in a transverse orientation.

 US Patent 3,253,355 (Menken) also describes the use of a rigid plate above an inflatable bladder. These plates are primarily intended to contain the pressure of the fluid inside the bladder in order to form a flat surface below the foot.

 I1 exist other patents which describe and pJ'qu intended to stiffen or strengthen the structure of the shoe, such as for example arch support devices and similar devices.

 Patent US-4,183,156 propose a "moderator" which, as described, uniformly distributes relatively large forces by being associated with chambers of the structure of the shoe which contain a fluid. he moderator is described as having a relatively modest thickness of 0.012 cm to 0.20 cm and it is "semi-flexible" to follow the shape of dynamic contours of the surface of the sole of the foot. However, this moderator of the prior art does not fulfill the function of an absorption mechanism, transfers of c, toekaye and energy restitution, but it is used only for the comfort of the foot.

Although the parts inserted, the support elements and the moderators described above, as well as others described in the prior art, coient cells to give satisfaction for the goals assigned to them, none of these devices of the state of the art does not prejudice the basic concepts of the present invention, namely
a) the use of one or more thin elastic elements, having a high modulus of elasticity, flattened or flexible to absorb the energy (if not wasted) produced by the foot during an impact of the latter
b) the redistribution of this energy in synchronism with the movements of the foot, so as to take advantage of this energy, if not wasted, to ensure other useful functions of the shoe, such as for example
1) to absorb and significantly reduce forces
which are imposed on the foot, on the
leg and body when walking,
run or jump and cause summer
riorations and injuries
2) to provide automatic and dyna support
mically perfected on the back of the foot
and heel, stability and control
movements directly proportional to the needs of the athlete; and or
3) to provide control and stability
automatic and dynamically improved
the forefoot, especially for
blocking and stopping movements
c the storage of this energy in a relatively efficient way inside the elastic system and
d) the return of this energy to the user of the shoe in a synchronized, dynamic and useful manner, in order to
1) improve overall efficiency,
2) reduce fatigue,
3) extend the "floating time" of the neck
laugh, and
4) increase the jump height of the "basketball" player.

 The present invention is intended to operate with, individually or in combination, a pneumatic fluid system and / or a support system made of an elastomer foam.

 More specifically, the stabilizer according to the present invention has, combined with elastomer elements and / or inflatable elements, a certain number of remarkable qualities and functions which have not been achieved until now. It is known, in the prior art, to use foam inserts or inflatable inserts normally used to form boots. US Patents 4,183,156 and US-4,219,945 describe inflatable inserts and.

combinations of these elements with elastomeric materials.

These latter patents represent an improvement over the state of the art, in that the first ones thus described absorb localized forces and redistribute these forces from the localized zone considered, the absorption of forces occurring throughout the system. to fluid from the first. Indeed, this fluid system acts like a pneumatic spring. However, these patents do not combine the elastomeric elements or inflatable elements with a moderator / stabilizer of the elastic type as in the present invention. The stabilizer of this invention, which is of the mechanical spring type, increases and improves the absorption of energy, the redistribution, the storage and the restitution of energy of the former of the aforementioned types.

When the first is an insert made entirely of foam and of a non-inflatable type, the stabilizer of the present invention provides advantages similar to those of compressed pneumatic fluid systems.

 In general, prior art stabilizers are either rigid and non-flexible without conforming to the shape of the wearer's foot, or rigid and non-flexible and designed to support the foot in a predetermined manner. Alternatively, some of these stabilizers from molding are flexible to conform to the shape of a desired configuration of the foot. In certain embodiments of the prior art, the energy of the localized charge imposed is simply absorbed, it is dissipated by being wasted and a small part of this absorbed energy, even if it exists, is restored in a useful form. When energy is only absorbed, it is usually dissipated in the form of heat which develops over a certain period of time, thereby producing an increase in temperature which can affect the comfort and service life of the shoe.

 With shoes to be used in sports-related activities or in rough physical activities, the interaction between the foot, the shoe and the support surface can vary widely, depending on the nature of the particular activity. , said shoe and said surface. For example, in long distance runs, heel shock, pronation and a "propulsion phase" by the toes occur which is followed by a "floating phase". In fact, the foot rests on the ground for only a relatively short period of time.

This period of time is, for example, less than 0.30 seconds and the effort imposed on this foot can be very high. In the attack phase of the heel, a mas-corresponding to between two and eight times that of the body acts from top to bottom on the heel for a relatively short period and the localized forces can be included in a range of about 1776 N to 7992 N. When the ground is hard, consisting for example of cement or bilume.dur, and the shoe is not compressible, the high forces are absorbed by the heel and transmitted by the bone structure corresponding to the rest of the body.Therefore, from the point of view of comfort and protection against injury, it is desirable to have a soft running surface
or a softly cushioned shoe structure, or a combination of the two.

 However, the toe propulsion phase tends to require firmness due to the propulsion mechanism. In this case, it is desirable to have a firmer surface and a less cushioned shoe structure, or even a combination of the two. For shoes of a given type, the effect produced may be different for different types of surfaces (for example grass, cement or hardwood). The grass gives way under the foot and, being a good tool, absorbs the attack of the heel better than cement or hard wood, its flexible nature makes propulsion by the toes more energetic. Cement and hardwood promote the dynamics of toe propulsion and hardwood is preferable to cement, since this hardwood is somewhat elastic and tends to dampen the attack of the heel. Hardly noticeable hardwood compared to cement seems at first glance not to matter, it is very significant from the point of view of the comfort of the foot and the protection of the athlete against injuries. This is first of all the reason why, in most gymnasiums, hardwood floors are used more readily than much cheaper cement floors.

 Due to the nature of distance running, it is important that the shoe used is designed not only to provide the desired degree of cushioning protection when attacking the heel, so that this shoe is also capable of (a) efficiently redistribute and store energy during the heel attack (this energy being made up of both negative force vectors acting downwards and backwards); and (b) returning this stored energy to the athlete in the form of a positive propelling force having both upward and forward acting components. In addition, this energy must be returned to the athlete. suitably synchronized with the rhythm of its pace (ie in synchronism with the articulated pendulum movement of its legs and feet, alnsi.qÜ'with the upward and downward movements of "bouncing ball" "of his head and torso), so as to encourage activity and not delay it.

In this respect, the importance of the appropriate synchronism of the restitution of the stored energy will be observed. If this energy is returned too quickly, it can actually affect overall efficiency and force a runner to run slower and less efficiently. If this energy is returned too slowly, the improvement in efficiency is weak or non-existent and this energy is purely and simply wasted.

 It may seem difficult or impossible to store enough energy inside the thin sole of a shoe to significantly improve the efficiency and performance of an athlete such as a long-distance runner.

Nevertheless, recent technological progress, which has achieved the above objectives, has been made in the field of sports shoes. This progress resides in the "Air-Sole" system (registered trademark) described in the applicant's prior patent No. 4,183,156. Extensive experiments carried out with hundreds of professional athletes have revealed efficiency gains within a range starting at s% and reaching up to 3 s% when using "Air-Sole" shoes. Even gains as small as 1% (as measured by tests on stationary test tables with oxygen supply) are physiologically significant and result in both increased speed and endurance of the athlete. , an energy saving of 0.8% is roughly equivalent to one minute and twenty-five seconds for a three hour marathon run, and about one minute for a two hour and ten minute marathon. Therefore, a comfortable and relatively light shoe, which increases efficiency by only one percent, represents significant and beneficial progress in the field under consideration.

 The nature of physical activity is an important factor in the design and production of shoes.

Long distance runs involve repetitive cycles (heel attack, pronation, toe propulsion followed by a floating phase) with reasonably identical types of effort. In the case of "basketball", for example, the situation is completely different because the cycle cannot be repeated because of the variety of movements in this sport. In addition, some of these movements are of a type such that, when the foot or any part of the latter comes into contact with the ground, the forces can be significantly greater and be exerted in directions different from those involved in the race.

For example, a "basketball" player can fall back on the socket or the heel of one of his feet after a high jump, so that the localized efforts significantly exceed those which are exerted normally during the heel attack phase of a long distance run. In addition, the nature of the sport is such that rapid starts, stops and changes of direction occur in a random and non-cyclical fashion. To some extent, the same remarks apply to sports such as American "football" or European "football" which are played on artificial turf, but the surface tends to be more elastic than the hardwood surface. Likewise, tennis is accompanied by the same variety of foot movements, although high jumps are not as frequent.

However, the surface is usually very hard.

 It is known from US Pat. No. 4,183,156 that particular types of embodiments of first inflatables described in this document are capable of absorbing localized forces and of storing and restoring mechanical energy to the foot and leg, so as to reduce the so-called "locomotion" energy required for running, walking and jumping. As described in the aforementioned patent, the displacement energy is absorbed by the first inflated from the foot when this foot comes into contact with the ground, the energy being converted into energy of fluid under pressure and stored inside of the first inflated, to then be converted back into movement energy at the end of the stride when the foot leaves the ground.The first described are initially filled with one or more combined special gases , inert, artificial and of great molecular weight in order to obtain essentially a permanent inflation combines with the remarkable faculties of automatic compensation (during a certain period) of the ambient variations of the pressure, so that the differential pressure (c ' that is to say the difference between the pressure prevailing inside the device and the surrounding pressure outside the latter) remains substantially constant for the longevity of the object. In this way, this object could be manufactured at sea level and be used in mountainous regions at altitude, while imparting the same "feeling" and the same quality of support. The reverse would also prove to be true (that is to say a manufacturing of the device in high altitude regipns, then its use at sea level).

 Although the first described above have many new and useful characteristics, work satisfactorily and include stabilizers to improve comfort, it has been necessary in certain applications to use relatively high inflation pressures and / or foams of great weight and relatively high density to resist the relatively large localized forces caused in certain types of activities, such as jumping. In addition, although the former were found to be effective in absorbing and ultimately converting energy into locomotion energy, maximum use of available energy could not be achieved. Redistribution of energy was a function of the communication passages of the air-gas mixture, thus requiring firsts whose configurations were relatively difficult to achieve in practice.

 One of the advantages of the embodiments of first inflatables was the adiabatic compression of the gas in reaction to the forces exerted and the transfer of energy at a relatively high speed approaching the speed of sound, that is to say 331, 6 m / sec. The energy was also transferred in the state stored right through in the plastic or in the elastomer which formed the envelope containing the fluid, but the speed of transfer of this energy was notably lower than that passing through the mixture. air-gas. In the case of foams, the speed of energy transfer is relatively low, for example about 30.48 cm / sec or less. As a result, in some cases, the dynamics of energy absorption, distribution and restitution are not properly "modulated" according to the activity of the user. This results in the the fact that the available energy is not used as optimally as it could be.

 Comfort and impact absorption are in themselves important factors which can increase the efficiency and performance of the athlete.

It has been shown that the body dispenses energy by the sole absorption and attenuation of the impact and shock forces occurring during running. In addition, muscles, ligaments, nerves, etc. Sore or even temporarily deteriorated do not work as effectively as normal constituents of the body. Therefore, the best possible embodiment of the shoe will optimize the factors (a) of comfort and shock absorption, (b) of lightness, (c) of absorption, redistribution, storage and effective return of energy, and (d) control of movement and support of the rear of the foot, the arch of the foot and the front of the foot. The "Air-Sole" system and variants of this system have achieved a significant degree of optimization of these factors which could not previously be achieved by any other shoe. However, shoe designs must meet special requirements that make the Air system
Sole "is not in itself the best embodiment.

In addition, the object of the present invention is capable of achieving many advantageous characteristics of absorption, redistribution, accumulation and energy restitution of the "Air-Sole" system without using this system, or else it can also be used to increase the overall performance characteristics of shoes fitted with the said "Air-Sole" system. The object of the present invention is particularly beneficial (in comparison with the "Air-Sole" system per se) in that it allows a remarkable and highly advantageous degree of control of the movements and of the dynamic support of the part to be achieved. rear of the foot, arch and forefoot, degree which cannot be achieved so far by the "Air-Sole" system or any other embodiment of a shoe. As will appear in the description below, the particular geometrical configuration and design of the elastic stabilizer absorb, redistribute, store and restore energy to the athlete in a manner advantageously different from that of the "Air-Sole" system or n ' any other devices of the prior art.

 In light of the above, one of the objects of the present invention consists in providing an improved stabilizer which cooperates with the other components of the shoe to absorb, redistribute, store and restore energy to the user, d 'A way much better than that which can be achieved by the same structure not equipped with the stabilizer according to the invention.

The other specific objects of this invention are
a) obtaining a "staggered training" effect between the foot and the surface on which the race takes place, in proportion to the applied force vectors
b) obtaining an improved ability to run,
by a suitable combination either with a first made entirely of foam and / or a first containing an air-gas mixture
c) improving the stability of the shoe
sure during the heel attack and toe propulsion phases, whether or not a first containing an air-gas mixture is used
d) the realization of an improved and increased support of individual parts qualified as "pronators"
e) cooperation with the heel counter of the shoe to create a dynamic acting suction cup effect. concomitantly with the heel counter to intimately adjust this heel in a firmer manner around the heel of the foot at times when there occurs between the foot and the ground rough impacts acting from top to bottom (or combined impacts acting laterally and from top to bottom)
f) to allow the use of softer foam and / or lower pressure air / gas mixture foam to ensure higher levels of comfort and impact / shock absorption, while more precisely modulating the shoe dynamics depending on the athlete and the activity considered, for example running, tennis, "basketball", triathlon, "American football", "football""European, etc.

g) the absorption, redistribution and storage of the energy of localized efforts and loads by a deformation of the elastic stabilizer, then a return of the energy to the athlete when the effort ceases;
h) when used with embodiments of shoes or shoes of the types described in patents US-4,183,156, US-4,219,156, US-4,219,945 and US-4,271,606, the stabilizing device of the present invention
1) supports the suitability of the entire structure
to absorb energy
2) achieves a better balance between
the comfort and firmness of the structure
the shoe
3) improves blocking characteristics and
stop "high jump" shoes
"basketball", tennis and other sports on courts;
and
4) increases and improves the characteristics
redistribution absorption, storage
and restitution of energy of said forms
shoes and premieres;
i) the advantage of using foam raw material components that are softer, less dense and therefore lighter, keeping the shoe soft while ensuring firmness and the energy restitution characteristics mentioned above
j) the possibility of using low pressure inflatable inserts and lower density foams, without having to endure their undesirable "bottom out" characteristics while retaining the feeling of soft damping, but with support closed
k) increasing and improving the absorption, redistribution, storage and energy release characteristics of the first foam or filled with the air-gas mixture; and
1) the possibility of obtaining a better degree of lateral support for the foot, therefore eliminating or reducing the need to provide reinforcement bands for sports shoes on courts, thereby allowing both a reduction in the weight of the court sports shoe or all-purpose athletic shoe, as well as an increase in the degree of support and control of movements of the entire foot.

 Thanks to the present invention, the energy consumption of the athlete is significantly reduced while allowing him to provide the same effort when the shoe is provided with a stabilizer according to the present invention, in comparison with the same shoe not having such a stabilizer.

 The aforementioned objects and advantages are obtained by an improved elastic stabilization device made of a material which has a high modulus of elasticity, which is light and which cooperates with other constituents of the first, of the inserted part or of the structure. of the shoe to absorb, redistribute, store and restore to the athlete, in a useful form and by an elastic deformation, the energy coming from localized efforts at the moment when these localized efforts cease. Indeed, the present invention provides firmness, support and stability accompanied by a softness and a damping effect, while restoring the energy absorbed in a useful form.

 The stabilizing device consists of a very thin material of the elastic type which is housed in the structure of the shoe so as to deform elastically and to absorb great forces per unit of area, and which acts simultaneously to redistribute these forces radially towards the exterior on the surface of the stabilizing element and on the elastically deformable material underlying or contiguous to said stabilizer. This energy absorption, transfer and storage function takes place almost instantaneously and in proportion to the force of the applied load. Thus, thanks to this scattering and this redistribution of the applied loads, the forces per unit area which are transmitted to other elements of the shoe are reduced, which allows the use of new, different and lighter materials.

 By way of comparison, systems with pressurized fluids such as the "Air-Sole" system absorb localized forces and redistribute and store this energy throughout the inflated structure, in a manner which depends on the geometric configuration. pressurized compartments forming the device. In essence, foam-based systems are not able to redistribute the force, or energy, of an applied load, away from the point or area of application of that load.

 When the elastic stabilizing device of the present invention is combined with the "Air-Sole" system, this results in new and very beneficial results.

There is a synergism which means that the object thus obtained has characteristics which cannot be achieved by the use of one of the two systems independently of the other. The performance and load absorption characteristics in pressurized fluid systems are markedly improved when using the present invention. Heavy localized loads which would normally cause skidding of the underside in the "Air-Sole" system are instantly dispersed (stabilized) above the air chambers so as to achieve load bearing characteristics of the system thus formed which are several times greater than those of a system without elastic stabilization, allowing the use of air pressures "more optimal low values and capable of achieving higher degrees of comfort under normal conditions of use.

 Therefore, the high modulus stabilizer comfortably and efficiently absorbs large impact forces when attacking the heel. The great efforts localized during this attack are absorbed and redistributed at the distal end of the calcaneus, both downwards and laterally. This redistribution characteristic can be controlled by variations in thickness, by the module and by the geometric configuration of the stabilizer or of the stabilizing elements.

At the initial stage of heel attack, the force applied is relatively modest and there is a small degree of load redistribution. When the heel attack continues and the forces develop, the continuation of the downward movement of the calcaneus causes (a) a noticeable elastic deformation of the central area of the heel stabilizer and (b) a redistribution of the localized load calcaneus, outward and above the softer support material formed by foam or filled with fluid. This results in a relatively soft and comfortable support under conditions in which the load and the force are weak to moderate. As the load increases, however, the stabilizing structure continues to deflect and disperse the load over a larger area. As a result, the system acquires greater firmness and provides greater support and the maximum impact load is absorbed without " bottom outlet "of the foam or fluid-filled component
During the operation described above> the moderating element is configured, despite its offset, to form a V-shaped or cup-shaped support surface, so that it automatically creates a system of force components directed towards the interior proportional to the applied load, so as to center the calcaneus in the shoe at the moment when the heel attack is greatest
In addition, the high modulus stabilizers can be extended in certain regions and extend upward around the periphery of the shoe in the heel and / or forefoot region, in order to create a system of firm lateral support, cantilevered and dynamically reacting inside the shoe, as shown in FIG. 3a of the description below, in order to convert downward forces from the calcaneus and / or the metatarsus (referenced by F1 and F2 in FIG. 5a of the drawings annexed to the present specification) in forces F3 and F4
opposed to 900, thus contributing to centering and stabilization
further reading of the heel and foot inside
the shoe.

 As a result, the load on the fatty tissue surrounding the calcaneus is reduced and a remarkable degree of control over the movements of the back of the foot is obtained, which is directly proportional to the instantaneous and variable needs of the athlete. This effect reduces the need to provide stiff heel buttresses and reinforcement bands which are intended to maintain the proper positioning and support of the heel of the foot inside the shoe. By the support and the centering of the calcaneus which it causes, the stabilizing device of the present invention exerts a "staggered training" effect on the heel in reaction to rapid changes in the direction of the movements of the body and it has the advantage of increased stability on uneven terrain, for example for cross-country races.

 In the fully deflected cup-shaped position, the stabilizer looks like a Belleville washer. The negative impact and impact energy (directed downwards and backwards) during the heel strike has been completely absorbed and stored in the high modulus deflected stabilizer and in the cushioning substrate or the material constituting the first, that is to say a foam or a material filled with a fluid. When the central point of pressure application moves forward beyond the maximum descending movement of the calcaneus during the heel attack, the load bearing area of the sole of the foot increases rapidly and , in the same way, the load applied to the heel stabilizer is rapidly reduced. At this stage, most of the negative vector energy resulting from a strong impact during the attack on the heel is restored to the foot ( calcaneus), to the leg and to the body by the elastic stabilizer in the form of a positive vector force.

 During total pronation, the calcaneus was therefore pushed upwards to a height substantially greater than at half the attack of the heel, thus stopping the downward movement of the center of gravity of the body and restoring it. athlete, in the form of an upward and forward force component, energy that would otherwise be unused. This effect initiates the upward and forward propulsion phase of the foot action a fraction of a second earlier and more effectively than would be the case without the presence of the elastic stabilizer.

 The stabilizer can have different types and configurations and it can be located in different places under the foot or in different places inside the structure of the shoe by exerting beneficial effects analogous to those described for the heel. Whatever the location of the stabilizer of the present invention, its characteristics reside in the fact that it shows a deflection without permanent deformation and in reaction to an applied load which generates bending stresses inside the stabilizing element. . When the applied load is gradually removed or reduced, the stabilizer returns to its original shape, thereby effectively stabilizing the energy that would otherwise be wasted to the user, given the ability of this elastic stabilizer to change its configuration by reaction to load variations shows a substantially zero time delay. In addition, the speed of the transfer of energy in the elastic material of this stabilizer is significantly greater than the speed of the transfer of energy through the air-gas mixture of the first filled with air and gas and / or the underlying layer of elastomer foam. As a result, the energy return corresponds more precisely to the speed at which the load varies. As a result, the shoe is "modulated" more precisely according to the movements of the foot and the needs of the user. . It is important that the stabilizer is made of suitable materials, that it has the correct shape and that it is correctly placed inside the shoe, so that it is able to deform and then turn over. to its initial shape. In this way, stabilizers suitably designed and optimized for specific applications make it possible to obtain a shoe (a) which is lighter; (b) which is more comfortable; (c) which is more energy efficient; (d) which is less tiring (e) which is more stable; (f) that reduces the risk of injury; (g) which better controls the movements of the back of the foot; (h) who has better control over pronation; and (i) which provides better support for certain medical and orthopedic devices used to correct certain defects of the foot and leg.

The invention will now be described in more detail with reference to the accompanying drawings by way of non-limiting examples and in which
Figure 1 is a plan and perspective view with partial section of a first shoe equipped with a simple stabilizing structure without overhang according to the present invention
Figure 2 is a plan view of a simple stabilizer structure without overhang in accordance with the present invention, for use as a heel stabilizer;
Figure 3 is a schematic view in partial section and in elevation of a shoe structure equipped with the stabilizer of the present invention, in a condition in which no load is applied
Figure 3a is a schematic section showing the relative locations of the stabilizer and the upper of the shoe and the heel counter in a condition in which no load is applied;
Figure 4 is a view similar to Figure 3 showing the relative positions of the parts of the structure of the shoe of the present invention under conditions of application of an average load
FIG. 4a is a section similar to FIG. 3a showing the relative positions of said parts of the shoe, in a schematic form, under a condition of medium load application
Figure 5 is a view similar to Figures 3 and 4, showing the relative positions of the parts of the shoe according to the invention under conditions of application of a large load
Figure 5a is a section similar to Figures 3a and 4a, schematically illustrating the relative positions of the different parts under conditions of application of a large load
FIG. 6 is a perspective view showing one of the alternative embodiments of the basic design of the stabilizer, comprising elastic dynamic support elements in cantilever
FIG. 7 is a perspective view showing another alternative embodiment of the dynamic elastic cantilever arrangement
Figure 7a is a cross section along line 7a-7a of Figure 7
FIG. 8 is a perspective view showing yet another alternative embodiment of an elastic stabilizing cantilever arrangement comprising a large number of individual elastic elements supported and held in position in a support structure of the fabric type and
FIG. 9 is a column diagram showing results of comparative tests of the energy storage and restitution efficiency of different foam, air and conventional stabilizing devices fitted and not fitted with the high modulus stabilizer. elasticity according to the present invention.

 Referring to the drawings which illustrate preferred embodiments of the present invention, Figure 1 shows a midsole, an insole or insole 10 for use in a shoe. In the type shown, this first one-piece composite comprises a layer of foam 14 which surrounds an element 12 inflated by an air-gas mixture which may be of the type described for example in US Pat. No. 4,219,945, in which the foam traps the inflated element 12 with several cells or cavities.

The first 10 can also be used in a thinner configuration, as the first slipped into an existing shoe, or it can also be used as the outer sole of a shoe.

 In the example considered, the stabilizer is in the form of a heel stabilizer 15 and a forefoot stabilizer 16, each of the latter being illustrated in dotted lines and being placed above the element 12 inflated by the air-gas mixture or made entirely of foam and placed inside the layer of foam 14.

The elastic stabilizer is placed at the top of this element 12. This makes it possible to obtain a unitary structure in which the stabilizer is associated with a damping material in the form of the inflated element made up of foam and filled with the air-gas mixture, which fulfills the functions described in the patents to which reference was made above.

 The stabilizers 15 and 16, which may consist of the same or different materials, are made of a material which is of the elastic type and has a high tensile modulus and an elastic modulus of at least about 1,722,500 kPa. Typical materials are high modulus plastics such as polycarbonates (with a modulus of about 2,067,000 kPa) available under the trade name "LEXAN", plastic compounds of the injection molded ABS type, of the type "E" and reinforced with glass fibers (having a modulus of elasticity of approximately 20,670,000 kPa); graphite compounds (with a modulus of elasticity of approximately 62,010,000 kPa) i and different types of metals such as steel, for example steel of class C-1075HTS (having a modulus of elasticity of approximately 206,700,000 kPa). Other materials that can be used are # 301 stainless steel, cold-rolled steel, heart-hardened stainless steel, class C-1095 blue-hardened, cold-rolled, cold-rolled steel. high carbon content and obtained by bainitic stepped quenching, and other alloys such as low or medium carbon content steel, hot rolled chromenickel steel, vanadium alloy steels, and other materials well known in the art. Stabilizers can also be made of spring steel or "cables", "ribbons" or heavy plastic filaments knitted or otherwise combined with a fabric. If desired, the surface of the material can be treated, especially that of metals, using an intermediate substrate such as "estamide" type resin manufactured by Upjohn, and / or by sandblasting or phosphate attack to improve adhesion .

 It is also possible to use other methods well known in the art to improve adhesion.

 Preferably, the material of which the stabilizer is made must have good resistance to fatigue due to the numerous cycles of repeated bending which occur in service, and it must also have the qualities of a good elastic material, that is to say ie an accumulation and a restitution of energy. This material constituting the stabilizer must have a sufficiently high modulus of elasticity, as well as the deformation energy which can be recovered by a deformed body when the stress causing the load is removed.

 Preferably, to act effectively without appreciably increasing the weight of the shoe, the moderator is light and preferably relatively thin in order to reduce the bulk. The thickness of the section of this stabilizer can be in the range of 0.012 cm to 1.27 cm and preferably in the range of about 0.015 cm to 0.5 cm. The stabilizer can have the same thickness from one end to the other, or its thickness can vary depending on whether or not it is necessary to have additional support in localized areas. Normally, the thickness of the section of this stabilizer is substantially uniform, although the heel and forefoot stabilizers, respectively, or the part of this stabilizer corresponding to the heel and forefoot, respectively, may be of different thicknesses or in different materials, or both, depending on the desired effect, or else can be laminated into compounds of different materials to obtain specific combinations of elasticity and support characteristics.

 Referring again to FIG. 1, the stabilizer 15 comprises a middle branch 18 along the internal face of the foot and a lateral branch 19 running along the outside of this foot, the stabilizer 15 of FIG. 1 as 'illustrated being intended for a shoe to be adjusted to the left foot. When it is intended for a shoe worn by the right foot, this stabilizer 15 is simply reversed.

As shown, the stabilizer 15 has a heel area 20 which connects the middle and lateral branches together so as to delimit an open region 21 at the front of the heel area and between the lateral and middle branches.

Instead of an open region 21 which is not elastic, this region 21 can be made of a considerably thinner and softer elastic material, so that the heel area and the lateral and middle branches cooperate with each other to exercise the functions of a Belleville washer, as described below.

 In the embodiment shown in the.

Figure 1, the stabilizer 16 of the forefoot is separated from that of the heel and it occupies a position such that it is in the load-bearing zone of the forefoot below the distal end of the metatarsus.

 The lateral face of the heel stabilizer ends at a short distance from the lateral face of the stabilizer 16 of the forefoot, thus allowing easy flexion in this region, while the median branch 18 is longer than the lateral branch. 19 to create a more stable surface for pronation control. The stabilizer 16 has recessed zones 23 and 24 arranged to allow bending in a longitudinal direction, with a zone 25 extending transversely over the width of the stabilizer.

Although bending is permitted, the stabilizer 16 permanently acts as a spring, both in the longitudinal direction and in the transverse direction. This particular design of a stabilizer assembly can be used in a court sports shoe; for example a "basketball" shoe.

 By now observing Figures 2 and 3 to 5 and their associated figures 3a to 5a, respectively, we will better understand the operation of the stabilizer. As shown in FIG. 2, this stabilizer is intended for a left foot and it comprises a lateral branch 31 and a middle branch 32. These branches 31 and 32 are connected to a heel area 33 delimiting an open region 35 at the front from the heel area and between the temples. Said open region 35 is intended to be located below the calcaneus.

 By observing FIGS. 3 and 3a, we can see the relative position of a calcaneus 50 in a shoe 40 fitted, for example, with a stabilizer 30 as shown in FIG. 2. This shoe comprises a uppers or an upper 41 and a outsole 43 provided with an element 44 filled with an air-gas mixture and trapped in a layer of foam 45.

The upper 41 of the shoe has a heel counter 42 provided with flaps 47, the stabilizer 30 being located between the upper part of the foam and below the flaps 47 which extend inwards towards the center of the shoe. A first classic 49 is located above the flaps 47.

 As can be seen from FIG. 3, the calcaneus 50 occupies, inside the shoe, a position such that it is aligned above the open region 35 of the stabilizer 30 and effectively rests on an underlying structure comprising a foam and a mixture of air and gas and actually forming a damping system. In the condition of FIG. 3, no load is imposed on the shoe and the relative positions of the different parts reflect the normal condition of the stabilizing device subjected to any stress. Figure 3a is a schematic section of the buttress 42 with the stabilizer 30 occupying no cantilever position below the flaps 47 as described above, and again in a load-free condition.

 Referring to FIG. 4, on which the same elements are given the same numerical references, and also observing FIG. 4a, it can be seen that, when a load is imposed on the heel1 the calcaneus is lowered somewhat in the structure underlying 44, 45 comprising a foam and an air-gas mixture, which results in a slight deflection of the stabilizer 30 under the action of the average force imposed on it. When this average force is imposed, the buttress 42 and the upper 41 of the shoe move from a position 42a in dotted line to position 42 in solid lines by teaching the foot firmly along its rear part around the rear. of the heel both along the lateral and median zones of this foot. When the calcaneus is lowered under the action of an effort, the stabilizer 30 is slightly offset like a Belleville washer, as illustrated in the FIG. 4a, in which case the external regions of the lateral and median edges curve upwards while the internal edges of these lateral and median zones are pushed downwards, as illustrated diagrammatically in FIG. 4a.

Therefore, the upper part of the shoe is pushed so as to tilt more firmly inwards against the interlocking of the heel of the foot in reaction to the imposed average force. When it shows such a deflection, the stabilizer absorbs, redistributes and stores the energy of the localized force, so that this force is transmitted radially outwards from one end to the other of the elastic stabilizer and d '' a progressive way as deflection occurs. Since the greatest force imposed from top to bottom is exerted in the area immediately below the calcaneus, there is a greater deflection of the internal edges of the two middle and lateral branches of the stabilizer 30. the average effort ceases, the stabilizer immediately recovers its initial configuration, and that to a large witostie (corresponds intimately to the speed with which the effort ceases. These movements of the different parts of the shoe emerge from a comparison of the figure 4 with figure 3 or figure 4a with figure 3. When it returns to its initial state, the stabilizer restores to the user
the energy absorbed in the form of stresses inside the stabilizing material when the forces exerted are imposed.

 As shown in FIGS. 5 and 5a, in which the same elements are again assigned the same reference numbers, the imposition of a large force results in a greater deflection than that represented in FIGS. 4 and 4a, d '' where it follows that the stabilizer elastically shows a greater deformation and is more strongly clamped between the interlocking of the heel and the upper of the shoe in the vicinity of the heel counter, so as to trap the calcaneus in the manner of a suction cup , to block it and to center the heel in the shoe, thus giving a firm and stable support under conditions of great effort, with a degree of efficiency substantially greater than that which has been obtained under conditions of average effort.

The effect exerted on the anterior end of the shoe is substantially identical, although firmer, in that the stabilizer 16 shows a deflection in reaction to the force imposed, thus absorbing the load and redistributing the energy over the area. of the interlocking of the foot, while storing the energy of the localized load. When the load ceases to be imposed, the stabilizer returns to its initial configuration and, in so doing, it restores to the utility.
energy which has been stored as a result of the deflection of said stabilizer, while also restoring
to the user the energy which has been stored in the foam damping material filled with an air-gas mixture, located
below the stabilizer in the region of the shoe corresponding to the forefoot.

 Dynamic laboratory tests of the elements of the shoe equipped with the stabilizing device of the present invention have revealed that a shoe designed according to the type shown in FIGS. 3 to 5; for example, has stored and restored impact energy with an efficiency greater than 16% than that of the same shoe structure not comprising the stabilizer according to the present invention (see FIG. 9).

 As described above, the stabilizer of the present invention significantly improves the performance of conventional shoes comprising only a first all foam as opposed to a cushioning system in the form of an air-gas system trapped in foam.

While this air-gas system per se performs significantly better than a full foam first system the stabilizer of the present invention also operates somewhat in a manner analogous to that described above when it is used in combination with shoe structures in which the stabilizer is installed above a cushioning means made entirely of foam. The action of this stabilizer is identical to that which has been described in support of Figures 3-5, although the amount of energy restored is not as great because the amount of energy stored in the foam does not is not as large as in an air and gas mixture system or in a combined airgaz system trapped in foam.

 As appears from the above description, the stabilizer of the present invention constitutes an improvement in activities such as running and in the case of sports activities on courts such as "baskct-bJ11" because, if the athlete's foot is on the median side or the lateral zone, there is absorption, redistribution and storage of energy since the entire stabilizing device is able to flex in response to the loads imposed More particularly, if an athlete shifts relative to the median side of the foot, the medial side of the stabilizing device flexes downward and the lateral zone tends to lift, thereby producing advantages comparable to those described, that is to say an intimate adjustment of the shoe around the foot to ensure comfort and support during the type of activity considered accompanied by a load support. In addition, a force vector is created which tends to push the foot back towards the center of the shoe. The elastic stabilization device thus exerts an automatic centering effect.

 The stabilizer 16 is provided with several strips or fingers extending transversely in the shoe in order to allow greater flexibility in the transverse direction, that is to say across the lateral and median zones of the foot.

 In FIGS. 6, 7, 7a and 8, the stabilizer 16 may have the shape of several strips or fingers 51 which extend from the lateral zone to the median side, the ends of these fingers having raised zones 52, 53, 55 and 57 in order to provide greater support around the edges of the shoe for the types of activities in which the forefoot exerts a certain action and in which the athletes can stand either on the medial side or on the lateral area of the forefoot. The upwardly cantilevered fingers show additional deflection to store energy, and to help exert a suction cup effect on the regions of the shoe corresponding to the toe and the heel, which presses these regions against the foot to provide additional comfort and support and to help prevent the forefoot from sliding sideways inside the shoe.

In accordance with the present invention, it is also possible to use a stabilizer only under the forefoot of the shoe, in particular for
shoes used in types of activities that do not normally involve heel shock; we will cite the example of speed races, in which the shoe has a studded area mainly below its end corresponding to the forefoot, and in which the heel of the shoe does not generally rub or strike the ground during the normal course of the sports competition.

In this type of structure, the same advantages are obtained as those described above.

In another embodiment of the stabilizer according to the invention, this stabilizer may include zones with a serpentine structure intended to cause increased bending and flexibility in certain regions of the structure of the shoe. For example, the area on the medial side of the stabilizer can be provided with a serpentine end which allows easy flexion in the area underlying the arch of the foot and concomitantly provides support for this arch. Likewise, the lateral face of the stabilizer may include a serpentine strip providing flexibility, while the region of this stabilizer located under the forefoot may also consist of a serpentine strip which, in fact, is provided with several parallel fingers with
adjacent fingers connected to each other by their opposite ends, thus ensuring flexibility and support in addition to the aforementioned functions. Some flexibility control in different directions can also be achieved by using stabilizers which have a different modulus of elasticity in different directions. For example, composite glass fibers or graphite compounds may exhibit significantly different stiffnesses in directions of mutual offset of 90 ".

 FIG. 9 is a column diagram summarizing tests and highlighting the relative efficiencies of the stabilizing device of the present invention in terms of energy absorption and restitution. We conducted a series of pendulum tests which basically consisted of allowing a pendulum, simulating the lower part of the leg and the foot, to strike the device under test (which was placed on a stationary frame), then to count the number d In the tests in question, the weight of the pendulum was approximately 20.43 kg and the specimens tested were rigidly supported by an appropriate support mechanism, so that the pendulum could oscillate freely, strike the specimens tested, rebound backward, then continue to swing forward and backward to freely strike the test specimens repeatedly. A count of the number of times that the tested specimens were struck until the pendulum stopped touching made it possible to obtain a relative indication of the efficiency with which the experimented device restored the energy to said pendulum. in the series, the experiment was repeated many times for each device tested and an average was established between the number of these experiments and the number of shocks for each device.

 In the first test, a comparison was made between a first filled with a mixture of air and gas, not trapped in foam, having substantially a structure as described in US Pat. No. 4,183,156 and inflated to '' at an approximate pressure of 1.7 bar to 1.9 bar. This air-gas system was one of the systems currently marketed by a shoe brand known under the name MARIAH. Numerous experiments have been carried out in which the number of impacts caused by a 20.43 kg pendulum has been counted until said pendulum ceases to strike the test specimen, and this number of impacts has found to be an average of 17.5.

In the identical test with the same material, a stabilizer was used which is substantially analogous to that shown in FIG. 2 and made of hardened class 301 stainless steel, with a thickness of approximately 0.025 cm. The stabilizer was placed on the first filled with air and gas tested in the first series and the result of numerous experiments with the second system revealed an average of 27.5 impacts in total. The increase of approximately ten impacts (or 57%) provides an indication of the relative energy return efficiency for the same air-gas mixture system depending on whether this system is equipped with the stabilizer of the present invention or not. .

 In another series of tests, a first perfected air-gas system using a nylon taffeta envelope inflated to about 1.7 bar to 1.9 bar was examined, showing an average number of 27 , 5 impacts.

The same material, used in a comparative test comprising the stabilizer already described, had 34 impacts. These tests, when repeated, produced remarkably consistent results. The differences in effectiveness are significant.

In a third series of tests, three different structures were tested in the following way: a structure A consisted of a system of air and gas mixture trapped in foam as illustrated in figure 1 of the present report and described in detail in patent US 4 219 945, and being in the form of a shoe commercially available, sold under the name
TAILWIND. A structure B was identical to structure A, except that it was equipped with a stabilizer, the configuration of which is illustrated in FIG. 2 of the drawings appended to this description, this stabilizer being made of hardened stainless steel to heart of class 301 and having a section thickness of 0.025 cm. A structure C consisted of the underlying layer of air and gas mixture foam of structure A, with the difference that the stabilizer (such as 'illustrated in Figure 2 of the accompanying drawings) consisted of a non-elastic material well known in the shoe industry and having a relatively low modulus of elasticity, less than 68 900 kPa. The commercial name of this material is "TEXON". The thickness of the section of this material was 0.20 cm. In structure C, the low modulus stabilizer was placed on the air-gas system tested in structure A. Each test was repeated many times and the results were averaged, which translates as following: (a) structure A: 25 impacts (b) structure B: 29 impacts; and (c) structure C: 22 impacts.

In another series of tests, three additional structures were examined, including a structure
To which was an ultra-light foam used as a first in a TERRA TC brand shoe. It was a special ethylene vinyl acetate / polyethylene copolymer. The second structure B was the first in ultra-light foam of test "A" equipped with a stabilizer in hardened stainless steel at the heart of class 301, with high modulus, the configuration of which is illustrated in FIG. 2 and the thickness of the section was 0.025 cm. The third structure C experimented with the first foam of test "A" comprising a low modulus stabilizer in "TEXON", as already described previously. Again, each test was repeated a number of times, which gave the following results: (a) foam first only 20 impacts; (d) foam first equipped with steel stabilizer: 28 impacts; and (c) foam first equipped with the "TEXON" stabilizer: 17.5 impacts.

 In the tests described above, the configuration of the stabilizer was the same and it was in approximately the same location for each test. During each of these, the pendulum was arranged so as to strike the specimen at approximately the same location as that at which the calcaneus would strike the device incorporated in a shoe.

 On the basis of the above data, the presence of a high modulus stabilizer significantly improves the energy absorption and restitution characteristics of the device examined. The use of a high modulus stabilizer in combination with a completely foam first improves these absorption and restitution characteristics up to a level higher than that of the same device not comprising the stabilizer, and also higher than those of air-gas mixture systems trapped in foam. The use of stabilizers with low modules has demonstrated a significant loss of efficiency when these stabilizers are associated either with systems of air-gas mixtures trapped in foam, or with systems entirely in foam. Nylon fabric "Air-Sole", which was coated with urethane and equipped with a high modulus stabilizer, made this system the most efficient of all those experienced in the series.

 Concrete tests carried out with professional athletes using special shoes according to the present invention are in progress. Currently, athletes who experiment with the device persist in preferring shoes fitted with the elastic stabilization device.

Several world records have recently been achieved by a world renowned athlete using the device of the invention.

 It emerges from the foregoing description that the use of a stabilizing device made of a material with high modulus of elasticity notably improves the performance of a shoe with regard to the absorption, redistribution and storage of energy. as a result of the deflection of the stabilizer under the action of applied forces, as well as the return in a useful form of energy to the user. The present invention aims to provide a stabilization device which comprises a stabilizer placed on an underlying cushioning structure, distinct from the structure of the shoe as manufactured and which can be inserted into any shoe.

 In addition to ensuring the described characteristics of energy restitution, the stabilizer of the present invention also confers the advantage of improved comfort and support. This is particularly true in the types of physical activity in which the attacker must start, stop, quickly change direction, jump, run on uneven or sloping terrain, or even run on roads whose coatings are hard. Unlike the stabilizers of the prior art, the stabilizer of the present invention is effective in that, by a deflection and an elastic return, it effectively returns to the user the energy which, until now and in certain state of the art systems; was dissipated and lost. In other dynamic tests (in which athletes have concretely experienced the shoes for the first time), in which an air-gas mixture system trapped in a foam and the stabilizer of the present invention were used, an increase was noted. athletes' efficiency of up to about 6% to 6%. This translates into a very substantial benefit for both professional and amateur athletes. This is especially true for long distance runners.

 It will be noted that numerous variations, modifications and / or additions can be made to the specific embodiments of the present invention illustrated in the drawings and described above, without departing from the scope of the invention.

Claims (17)

 1. Shoe comprising a top or upper (41) and at least one sole (43) secured to said upper, so that the user's foot is placed inside said upper (41) and above of said sole (43), this shoe (40) also comprising a damping material (44,45) interposed between said sole and the foot of the user, shoe characterized in that it comprises a stabilizer (30 ) high modulus of elasticity inserted between the foot of the user and the damping material (44,45) to which it is overlying; by the fact that this stabilizer (30) is relatively thin, light and made of a material having a modulus of elasticity of at least about 1,722,500 kPa; by the fact that said stabilizer (30) can show a deflection without permanent deformation in reaction to the application of a force which causes a bending stress inside this stabilizer, and recover its initial configuration when said force ceases to 'to be applied ; and by the fact that, by its deflection, said stabilizer (30) acts to absorb, redistribute and store the energy of localized forces imposed on it, and to restore this energy to the user, with a speed equal to or greater than the speed at which the application of the force ceases.  2. Shoe according to claim 1, characterized in that the stabilizer (30) has a section thickness between 0.012 cm and 1.27 cm.  3. Shoe according to claim 1, characterized in that the stabilizer comprises a part (15) under the heel and a part (16) under the forefoot.  4. Shoe according to claim 1, characterized in that the stabilizer comprises a part (15 30) located under the heel, this part underlying the heel having a middle branch (18; 32), a lateral branch (19; 31) and a heel area (20; 33); and by the fact that said lateral branch (19; 31) is spaced from said central branch (18; 32) to form an open region (21; 35) located at the place where the calcaneus (50) of the foot is housed in the shoe.  5. Shoe according to claim 1, characterized in that the stabilizer (16) is located in the region of said shoe corresponding to the forefoot.  6. Shoe according to claim 1, characterized in that the stabilizer (15) is located in the region of this shoe corresponding to the heel.  7. Shoe according to claim 1, characterized in that the stabilizer is made of a metal endowed with elasticity.  8. Shoe according to claim 4, characterized in that the middle branch (18; 32) is longer than the side branch (19; 31).  9. Shoe according to claim 4, characterized in that the lateral branch (19; 31) is longer than the middle branch (18; 32).  10. Shoe according to claim 1, characterized in that the cushioning material consists of a foam (14).  11. Shoe according to claim 1, characterized in that the material --d' amortization consists of a system (12, 14) containing a mixture of air and gas and trapped in a foam.  12. Shoe according to claim 1, characterized in that the cushioning material consists of an element (12) filled with a mixture of air and gas.  13. Shoe according to claim 1, characterized in that regions of the median and lateral faces of the stabilizer (30) are extended from about 1.27 cm to 2.54 cm, these extended regions projecting upwards, with an orientation of approximately 90, beyond the plane of said stabilizer.  14. Shoe according to claim 13, characterized in that the extended regions or elastic cantilever elements (51,55,57) are divided.  15. Stabilization device for use with a shoe and characterized in that it comprises a stabilizing element (30) of high elastic modulus, which is relatively thin, light and made of a material having a modulus of elasticity of at least about 1,722,500 kPa; a damping material (44,45) located below said stabilizing element (30) to allow a deflection of this element without any permanent deformation, in reaction to a force which is imposed on it, causing a bending stress and allowing said element to recover its initial configuration when said force causing said bending stress ceases to be imposed; and an element (49) overlying and cooperating with said stabilizer element (30) to form a composite insert which can be placed in any shoe (40).  16. Stabilization device according to claim 15, characterized in that the stabilizing element (30) comprises a lateral branch, a middle branch and a heel area; and by the fact that said lateral and median branches are spaced from each other to form a region which is intended to receive the calcaneus (50).  17. Stabilization device according to claim 14, characterized in that the stabilizing element (30) comprises several elastic members with configurations  which are woven or otherwise placed and supported in a parallel structure, by means of a fabric or flexible fabric.