The present disclosure relates to a shoe that can be described as high performance.
In document US-B1-8 079 159, there is described a shoe extending between a toe and a heel and comprising an upper attached to an outsole.
The shoe described in document U.S. Pat. No. 8,079,159 has a modular sole structure comprising, from bottom to top:
In document US-2011/0179669 A1, there is described a shoe extending between a toe and a heel and comprising an upper attached to an outsole.
However, improvements are needed.
The object of the present disclosure is to propose an improvement to the performance of an outsole of the type mentioned above, and in particular, to propose a soling construction which has a guiding, holding, cushioning, and relaunching effect due to a scalable center of mass.
One or more of the goals may be addressed in the shoe claimed in the present disclosure. According to the indications in the introduction, this athletic shoe is characterized in that the comfort sole has a radius of curvature at any point of a line from the heel to the tip and interfacing with the outsole, and in that the lowest point of the comfort sole and/or outsole, called the center of mass or natural balance point of the shoe, when placed on an appreciably horizontal reference plane, is the transition zone of the roll of the foot having the highest sole radius, and in that the center of mass is located behind the point of the metatarsals.
This construction of the sole produces beneficial results for use in running, but also, depending on the case, for walking or other uses.
The sole may comprise a shell comprising, consisting essentially of, or consisting of a shell bottom and a shell side.
Due to the mechanical connection of the shell and the comfort sole, the lines of force are stabilized. The rise of the shell sides makes it possible to obtain an additional stability effect through compression of the upper, which is added to the stability effect linked to the gluing of the shell to the comfort sole and also prevents the arch being pushed up the foot in the static and dynamic phases.
Of course, the construction mentioned above is not limited to application in races, and can also be very beneficial in other areas, particularly walking and other uses. According to the aim sought during the practice of physical activities such as walking, running, etc., the present disclosure enables or prevents excessive deformation of the comfort layer in the impact and flexion phases of the foot.
Therefore, in the example shown, the shoe is particularly intended for racing, especially on rough terrain. It has a fairly low upper and a damping outsole; nevertheless, it is low enough so as not to damage the stability of the foot on uneven ground or on a slope.
The present disclosure will be better understood using the description and accompanying schematic figures, which illustrate several non-limiting aspects by way of example. Based on the description and figures, those skilled in the art will be able to deduce other advantageous characteristics of the shoe.
The underside of the comfort sole, which is in contact with the outsole, has a substantially convex curvature. The side of the comfort sole has a radius of curvature at all points of a line from the heel to the toe and creates an interface with the outsole. The lowest point of the comfort sole, called the center of mass or natural balance point of the shoe, when placed on an appreciably horizontal reference plane, is the transition zone of the roll of the foot having the highest sole radius. The center of mass is scalable and located behind the point of the metatarsals.
In order to promote the roll of the foot, an example of a sole is shown in
In the static phase, in order to find stability on a flat part, a radius of Zone (Z1) that is sufficiently open will be chosen. Thus, the part of Zone (Z1) of comfort layer (9) will be crushed by the weight of the user. It is advantageous for the radius of Zone (Z1) to be between 350 mm and 3000 mm. Of course, this range of values of the radius of Zone (Z1) is only indicative, and those skilled in the craft will know how to choose other values of the radius if necessary.
The transition phase between the impact and the roll of the foot is immediate and without energy loss thanks to the center of mass and the more pronounced dip of Zone (Z4), which is located under the metatarsals. This makes it possible to increase and facilitate the roll of the foot and to obtain a greater range of motion and an optimized push-off phase. Strides become faster and more powerful.
It is, of course, obvious that the absolute and relative values of the radii listed above are only indicative. Indeed, the fields of application and/or physical activities envisaged, as well as the different morphologies of the potential users, such as type and size of foot, weight, type of stride, etc., may also have an influence on the choice of the radii of Zones (Z1 to Z5). Thus, those skilled in the craft may envision a number of zones less than or greater than 5.
The shoe will, however, include at least 3 zones. The two zones on either side of Zone (Z1) corresponding to the center of mass then have radii smaller than that of the center of mass.
When the shoe comprises more than 5 zones, the radii of each zone other than (Z1) may have a radius equal to or different from an adjacent or non-adjacent zone. It is, of course, essential that side of the comfort sole have a radius of curvature at all points of a line from the heel to the toe and creates an interface with the outsole, and that Zone (Z1) corresponding to the center of mass has a radius greater than the two adjacent zones.
Similarly, in order to promote the roll of the foot and to minimize the transition phase between the first impact and center of mass (A), point (C) corresponding to the heel of the outsole and/or comfort sole (9) is set back or at the same level as the part of the upper furthest from the center of mass. This principle, which has the effect of advancing the contact point to Zone (A) as much as possible, favors the dynamic phase of the walk, on flat ground as well as on inclines.
This configuration allows outsole (7) to advance the first contact zone towards the center of mass as far as possible during the natural roll of the foot and to remain in contact during the first phase of impact on the ground; this happens during the entire phase of the roll of the foot regardless of where the foot is placed, without generating a second impact.
As indicated in
Comfort sole (9) is made of a material that ensures comfort and keeps the foot in place. It is made of a damping material such as rubber or EVA. The comfort sole may also be PU (polyurethane), or any other natural or synthetic foam. PU is harder, and therefore offers less immediate comfort than EVA. However, it is more durable and will have more flexibility over time. The rubber is very soft and very flexible, but it is heavier. The cushioning material of the comfort layer may also be a material having elastic or viscoelastic properties, such as elastomer.
In
As mentioned above, the lower part of comfort sole (9), which is contiguous with outsole (7), has a radius of curvature at any point on a line from the heel to the toe, and creates continuity on both sides with center of mass (A). This configuration allows outsole (7) to always remain in contact in the first phase of impact with the ground and during the entire phase of the roll of the foot, regardless of where the foot is placed, without generating a second impact, thanks to the mechanical connection that stabilizes the lines of force of shell (13) and comfort sole (9).
Outsole (7) is made of any synthetic or natural material offering the properties necessary for outsoles, such as adhesion and wear resistance. The nature of the material used for the outsole is not limited to the usual materials in the field of shoes. It will be chosen according to the envisaged use of the shoe, the nature of the ground, the adhesion and the desired wear resistance, etc.
As shown in
Molded shell (13), which has the shape of the shoe's last, decreases impact and energy loss during the support phase. It positions the body correctly, without any effort, in order to execute strides optimally.
Shell (13) also helps to promote the crush of the center of mass without deforming the arch. In addition, this shell imparts torsional and flexural rigidity to the upper that counteracts foot displacement during impacts between the heel of the shoe and the ground and thus contributes to the stability of the support and increases the comfort sole's flexural rigidity.
Shell (13) comprises, consists essentially of, or consists of a shell bottom and a shell side rising towards upper (5). The rise of the shell side makes it possible to obtain an additional stability effect through compression of the upper, which is added to the stability effect linked to the gluing of shell (13) to the comfort sole.
In another aspect, as shown in
The shell is also asymmetrical to help hold the foot. In the lateral zone, the shell side is higher and longer towards the toe in order to favor the stabilization of the arch.
As shown in
The number of notches is, of course, variable. They are not necessarily an even number and in perfect opposition.
The shell sides are also glued to the surfaces in contact with the outsole. Shell (13) also imparts torsional and flexural stiffness to the upper, longitudinally and laterally.
The preferred manufacturing materials for the shell are loaded or non-loaded polyurethane (PUR, TPU), loaded or non-loaded polyamide (PA), polyethylene (PE), and generally all loaded or non-loaded synthetic materials.
Composite materials, for example, based on fiberglass/carbon fiber and synthetic resin, are also options.
We can also consider the use of metallic materials and, for example, aluminum alloys, or natural materials such as bamboo or other wood fiber.
For each shell, the thickness will be a function of the desired degree of elasticity and the Young's modulus of the chosen material.
Depending on the desired applications, the shell and the comfort sole may have similar or different stiffnesses. In the latter case, a shell (13) can be chosen that is more rigid than comfort sole (9), or vice versa.
According to
In another aspect, shell (13) is recessed in different areas of the shell bottom,
Thus,
The openings according to
In
Although the invention has been described in particular with respect to preferred aspects, it is obvious to those skilled in the craft that these aspects as described in the figures and in the description are not limiting in nature. It is clear to those skilled in the craft that variations other than those described and shown may be contemplated without departing from the scope of the invention as defined in the claims.
Number | Date | Country | Kind |
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18/01085 | Oct 2018 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/US2019/056321 | 10/15/2019 | WO | 00 |