Patent Application
20130074371
1. Field of the Invention
The invention relates to footwear, such as a shoe, and more particularly a shoe intended for the practice of sports.
Footwear of the aforementioned type can be used in disciplines such as walking, including power walking, running on flat or mountainous terrain, hiking, skateboarding, a ball or racket sport, and the like.
2. Background Information
An article of footwear, or shoe, of the aforementioned type comprises an outer sole assembly and a generally flexible upper, which can be a low or high upper, or even a mid-upper. Each shoe is structured to provide a user with the best conditions of use, whereby the user is comfortable when moving or being supported, or in relation to the transmission of impulse forces, the perception of sensory information, and the like. The logical consequence is that a large proportion of users can practice their activities with comfort. However, there are users who still experience discomfort.
Indeed, certain people have a valgus deformity, whereby one or both of their lower limbs is/are turned outwards. In other words, such people have at least one genu valgum, which is an outward angulation of the axis of a lower limb, with the knee projecting inward: the knees touch one another while the ankles are spaced apart. This condition can interfere with walking, running, or other movements of the legs. In response to this condition, the prior art has proposed specific structures for footwear.
For example, the outer sole assembly of certain footwear has been structured so that, when receiving support forces or during transmission of various forces, the axis of the lower leg is guided inward, so as to prevent an increase in, or even reduce, genu valgum. In other words, this seeks to ensure that the legs are not as close to one another in the area of the knees.
Conventionally, the sole assembly extends lengthwise from a rear end to a front end, widthwise between a lateral side and a medial side, and heightwise between a surface of contact with the ground, adapted to take support on the ground, and a connecting surface, adapted to be connected to the remainder of the shoe, typically to the upper. From the rear end to the front end, the outer sole assembly has a rear zone adapted to be located in the area of the heel of the foot, a central zone located in the area of the plantar arch of the foot, a metatarsal zone located in the area of the metatarsus, and a front zone located in the area of the toes.
In addition, the outer sole assembly generally comprises a plurality of layers, including a wear layer demarcating the surface of contact with the ground, and a damping layer providing a certain comfort.
Improvements in terms of reducing or preventing the consequences of genu valgum, according to the prior art, have involved an increase in the hardness of the outer sole assembly, in the vicinity of the medial side and mainly in the central zone. In other words, the prior art has sought to increase the support of the arch of the foot. In practical terms, the damping layer of the outer sole assembly has been split. Therefore, this layer comprises a flexible main portion, which extends along the entire length and across the entire width of the outer sole assembly, as well as a smaller portion, which extends substantially in the central zone, in the area of the medial side. This smaller portion is more rigid, or less flexible, than the main portion.
As a practical consequence, the lateral portion of the sole of the foot comes closer to the contact surface than does the medial portion, in the area of the arch of the foot, during the various supports or forces that compress the outer sole assembly. In fact, during supports, the foot tilts transversely, with its medial side remaining higher. As a result, the shoe, by the action of the outer sole assembly, biases the lower limb in a direction of reduction of the genu valgum. Therefore, users with this particularity have been provided with better conditions for the practice of their activity, be it walking, running, or the like. However, in spite of this improvement, users, or a number of them, still experience discomfort. The problem of knock knees has not been resolved.
In summary, it can be said that a user who has genu valgum, a condition also known as knock knees, is generally hindered, more or less severely depending upon the degree of genu valgum, when walking, running, or practicing sporting activities, such as those mentioned above.
In view of the preceding, the invention generally improves upon footwear of the prior art. In particular, the invention reduces to the maximum, or even eliminates, the discomfort that can result from valgus knees while allowing practice of a sport.
More broadly, as will become apparent below, the invention prevents the knees of any user from coming closer together.
To this end, the invention provides a shoe comprising an outer sole assembly and a flexible upper, the outer sole assembly extending lengthwise from a rear end to a front end, widthwise between a lateral side and a medial side, and heightwise between a surface of contact with the ground and a surface for connecting to the remainder of the shoe, the outer sole assembly having, from the rear end to the front end, a rear zone, a central zone, a metatarsal zone, and a front zone, the shoe comprising a counter reinforcing the upper, at least above the rear zone.
The counter of a shoe according to the invention comprises a lateral flange and a medial flange, the medial flange being longer than the lateral flange.
The medial flange forms a transverse stop which supports the upper, in its lower portion, in the area of the medial side. The medial flange therefore retains the upper on the medial side, thereby preventing or limiting a displacement or deformation of the base of the upper, in the area of the counter and on the medial side, in a direction extending from the lateral side to the medial side. It can be said that the medial flange opposes a transverse displacement and/or a transverse inclination of the lower part of the upper, in the area of the counter on the medial side.
Consequently, the shoe according to the invention limits the deformation of the foot in the transverse direction, in the area of the medial flange, in a direction extending from the lateral side to the medial side. The deformations in question are those related to the gait cycle, during which the height of a cross section of the foot decreases while its width increases and then, alternately, the height increases as the width decreases. The cross section considered is in the area of the medial flange. This means that the reversible widening of the cross section of the foot mainly occurs on the lateral side. In other words, it can be said that the foot is held better in the area of the medial flange, on the medial side of the shoe. Consequently, the outward inclination of the lower limb, that is to say, of the leg, is limited, or even prevented.
It follows advantageously that the hindrance that can result from a valgus deformity is reduced, or even eliminated. This advantage is more or less pronounced depending on the user, but it appears nevertheless that the relative coming closer together of the knees is, to say the least, stabilized, or even reduced.
Moreover, as will be understood from the description below, the outer sole assembly comprises a damping layer, which itself comprises a first portion and a second portion, the first portion extending at least in the rear zone, in the central zone and in the metatarsal zone, the first portion demarcating a medial cavity that is spaced from the connecting surface, the medial cavity extending at least in the central zone, the second portion being at least partially housed in the medial cavity, the second portion being harder than the first portion.
Due to this arrangement, the lateral portion of the sole of the foot is closer to the contact surface than the medial portion, in the area of the arch of the foot, during the application of various support forces or forces that compress the outer sole assembly. During the application of support forces, the foot tilts transversely, with its medial side remaining higher. This effect adds to that obtained by the counter.
Also, a lip extends the first portion in a direction away from the contact surface, in the area of the medial side, opposite the counter. Like the medial flange of the counter, the lip forms a transverse stop which supports the upper, in its lower portion, in the area of the medial side. The lip therefore retains the upper on the medial side, thereby preventing or limiting a displacement or deformation of the base of the upper, in the area of the counter and on the medial side, in a direction extending from the lateral side to the medial media. It can be said that the lip opposes a transverse displacement and/or a transverse inclination of the lower part of the upper, in the area of the counter, on the medial side.
Consequently, the shoe according to the invention limits deformations of the foot in the transverse direction, in the area of the lip, in a direction extending from the lateral side to the medial side. The deformations in question are those related to gait cycle, during which the height of a cross section of the foot decreases while its width increases and then, alternately, this height increases as the width decreases. The cross section considered is in the area of the lip. This means that the reversible widening of the cross section considered of the foot occurs mainly on the lateral side. In other words, it can be said that the foot is held better in the area of the lip, on the medial side of the shoe. Consequently, the outward inclination of the lower limb, that is to say, of the leg, is limited or prevented.
Other characteristics and advantages of the invention will be better understood from the description which follows, with reference to the annexed drawings illustrating, by way of non-limiting embodiments, how the invention can be embodied, and in which:
The first embodiment, which is described with reference to
As shown in all
Conventionally, the shoe 1 includes an outer sole assembly 2 and a flexible upper 3. The shoe 1 extends lengthwise from a rear end 4, or heel, to a front end 5, or tip, and widthwise between a lateral side 6 and a medial side 7. Therefore, the outer sole assembly 2 extends lengthwise from the heel 4 to the tip 5, and widthwise between the lateral side 6 and the medial side 7. The sole assembly 2 also extends heightwise, or depthwise, between a contact surface 8 and a connecting surface 9. The contact surface 8 is adapted to contact the ground. The connecting surface 9 is used to affix the sole assembly 2 to the remainder of the shoe, using an adhesive, for example.
As shown, the upper 3 includes a lower portion 10, provided to surround the foot, and has no upper portion, that is, the upper in
To facilitate the description of the shoe, the outer sole assembly 2 is said to have four successive zones. From the rear end 4 to the front end 5, the sole assembly 2 has a rear zone 21 located in the area of the heel of the foot, a central zone 22 located in the area of the arch of the foot, a metatarsal zone 23 located in the area of the metatarsus, and a front zone 24 located in the area of the toes.
The outer sole assembly 2 includes a damping layer 25, which itself includes a first portion 26 and a second portion 27. Generally speaking, the first portion 26 extends at least in the rear zone 21, in the central zone 22, and in the metatarsal zone 23. The first portion 26 is adapted to dampen impacts or impulses that pass through the outer sole assembly 2. Thus, the first portion 26 is made of synthetic foam material, for example, such as acetyl-butadiene-styrene, or any equivalent material.
In a non-limiting fashion, and according to the first illustrated embodiment, the first portion 26 of the damping layer 25 extends in the rear zone 21, in the central zone 22, in the metatarsal zone 23, and in the front zone 24. This provides a damping effect on the entire sole of the foot.
The first portion 26 of the damping layer 25 demarcates a medial cavity 28 spaced from the connecting surface 9, as in seen particular in
Because the medial cavity 28 is spaced from the connecting surface 9, a tapered subdivision 29 of the first portion 26 extends between the second portion 27 and the upper 3. This enables a certain damping of impacts or impulses in the area of the arch of the foot, on the medial side.
In a non-limiting fashion, the medial cavity 28 opens out in the area of the medial side 7 of the outer sole assembly 2, and in the area of a lower surface 30 of the damping layer 25. This facilitates the manufacture of the sole assembly 2. The surface 30, opposite the connecting surface 9 depthwise of the damping layer 25, is adapted to be affixed to a wear layer 35, as explained below.
The shoe 1 comprises a counter 36 that reinforces the upper 3, at least above the rear zone 21. The structure of the counter 36 is additionally described below, it has the function of particularly improving the support of the heel of the foot.
A lip 37 extends the first portion 26 in a direction away from the contact surface 8, in the area of the medial side 7, opposite the counter 36. The lip 37 retains the upper on the medial side and prevents or limits a displacement or deformation of the base of the upper, in the area of the counter and on the medial side, in a direction extending from the lateral side to the medial side. This allows for better foot support in the area of the lip, and, consequently, a reduction, or even elimination, of the discomfort resulting from genu valgum.
According to the invention, as can be seen in
According to the first illustrated embodiment of the invention, the maximum heights of the lateral 38 and medial 39 flanges of the counter are equal. This provides the upper 3, above the counter 36, with the same flexing ability on the lateral side and medial side. This configuration is appropriate for walking or running, at least under normal conditions. But it may alternatively be provided for the maximum heights of the flanges 38, 39 to be different.
The counter 36 is comprised, for example, of a solid synthetic material, so that the flanges 38, 39 and the bridge 40 form a unitary element. This material can be polyurethane, polyamide, or any equivalent material.
In a non-limiting fashion, the second portion 27 has a thickness e which decreases in the transverse direction, from the medial side 7 to the lateral side 6. This arrangement provides the damping layer 25 with elastic deformation ability under compression, which varies transversely for the application of the same load. The variation is gradual. In fact, the boundary between the first portion 26 and the second portion 27 is a downward slope toward the lateral side 6. The outer sole assembly 2 becomes less and less hard along the slope, up to the lateral side 6. Alternatively, a constant thickness e can be provided for the second portion 27. In such a case, the transition, between a high-strength subdivision of the layer 25 and a low-strength subdivision of the layer 25, would be more pronounced. In any case, the foot is better supported on the medial side, at least in the area of the heel and of the arch.
In a non-limiting fashion, the second portion 27 extends widthwise along a distance between 20% and 80% of the width of the outer sole assembly 2, while values between 25% and 60% have yielded good results. This preserves a substantial damping amplitude on the lateral side 6, in spite of the support precision provided on the medial side 7 by the second portion 27.
Still with respect to the dimensions, the second portion 27 extends lengthwise along a distance between 30% and 75% of the length of the outer sole assembly 2, from the rear end 4. In other words, the second portion 27 stops in the metatarsal zone 23 without reaching the front zone 24. It follows that damping is uniform over the entire width of the shoe 1, in the area of the toes. This allows for a very good perception of projections and, as a result, high accuracy when taking support on the ground.
The shoe 1 is constructed so that the lower surface 45, or bottom surface, of the second portion 27 is flush with the lower surface 46, or bottom surface, of the first portion 26. These two surfaces 45, 46 together form the lower surface 30 of the damping layer 25. This surface 30 is uniform for easy connection with the wear layer 35.
Still, within the scope of the invention, the lip 37, which can be said to be medial, extends lengthwise in the rear zone 21 and central zone 22. The lip 37 therefore supports the upper 3 transversely in the two zones 21, 22. This specific localization reinforces the upper 3 in the area of the counter 36, whose position is stabilized in the transverse direction and in a direction extending from the lateral side 6 to the medial side 7. As a result, the base of the upper 3 is less flexible in the area of the medial side 7 than it is in the area of the lateral side 6, if one compares the flexibility within a transverse cross section of the shoe 1 that passes through the lip 37, as is the case in
It can be said that the shoe 1 has a single lip 37, which makes the outer sole assembly 2 transversely asymmetrical, in the sense that, in the area of the counter 36, the lip 37 is a medial upward extension of the outer sole assembly 2. The asymmetry arises from the fact that the outer sole assembly 2, via the lip 37, extends farther upward on the medial side of the upper 3, in the area of the counter 36, than on the lateral side of the upper 3.
The aforementioned effect is obtained in particular if, as is the case with the first embodiment, the general structure of the upper 3 is the same on the lateral side 6 and on the medial side 7. In this case, the upper 3 includes an outer shell 51 and an inner liner 52, the counter 36 being located between the outer shell 51 and the inner liner 52. Alternatively, the counter 36 could be positioned outside of the upper 3, by covering a portion of the outer shell 51.
According to the first embodiment, the lip 37 extends heightwise along a distance between 10% and 40% of the height of the counter 36. This distance is sufficient to retain the counter 36 and, therefore, the base of the upper 3.
In a non-limiting fashion, the lip 37 and the first portion 26 form a unitary element. The goal here is to simplify the manufacture of the shoe, in which the constituent elements of the damping layer 25 are obtained, for example, by molding.
As discussed above, the outer sole assembly 2 includes a wear layer 35. It is this layer that defines the contact surface 8. The wear layer 35 is affixed, for example by means of an adhesive, to both the first portion 26 and the second portion 27. The wear layer 35 has an average thickness, that is to say, varied by the relief of the contact surface 8, substantially constant, in transverse and/or longitudinal direction. The wear layer 35 here is continuous longitudinally and transversely, from the rear 4 end to the front end 5, and from the lateral side 6 to the medial side 7. However, the layer 35 may alternatively be discontinuous and have different subdivisions distributed along the contact surface 8.
Also, according to the first embodiment, the shoe 1 includes an insole 53, which can fulfill various functions, such as improving hygiene of the shoe, or complementing the effects of supporting or cushioning the foot.
The other embodiments are described below with reference to
For the second embodiment, according to
What is specific to the second embodiment is that the lip 57 extends the second portion 27 in a direction away from the contact surface 8, in the area of the medial side 7, opposite the counter 36. More precisely, the lip 57 and the second portion 27 form a unitary element. Compared to the first embodiment, this is an alternative construction, which provides the outer sole assembly 2 with increased rigidity on the medial side 7. Therefore, the transverse retention of the counter 36 is firmer. The second portion 27 extends widthwise along a distance between 20% and 70% of the width of the outer sole assembly 2, from the medial side 7. For the second embodiment, the transition in stiffness between the lateral side 6 and medial side 7 is fairly abrupt.
For the third embodiment, according to
What is specific to the third embodiment is that not only the lip 67 extends the second portion 27 in a direction away from the contact surface 8, in the area of the medial side 7, opposite the counter 36, but the second portion 27 also extends along the entire width of the outer sole assembly 2. More generally speaking, the second portion 27 extends widthwise along a distance between 20% and 100% of the width of the outer sole assembly 2, from the medial side 7. Moreover, the second portion 27 has a thickness e which decreases in the transverse direction, from the medial side 7 to the lateral side 6.
Ultimately, the sole assembly 2 according to the third embodiment provides a very gradual variation in transverse rigidity.
For the fourth embodiment, according to
What is specific to the fourth embodiment is that the first portion 26 includes a plurality of sub-portions 71, 72. In a non-limiting fashion, the first portion 26 includes a first sub-portion 71 and a second sub-portion 72. The first sub-portion 71 extends along the entire width of the outer sole assembly 2, from the lateral side 6 to the medial side 7. The lip 37 and the first sub-portion 71 form a unitary element. The second sub-portion 72 extends width-wise along a distance of between 20% and 70% of the width of the outer sole assembly 2, from the lateral side 6. The second sub-portion 72 is located, depthwise of the sole assembly 2, between the first sub-portion 71 and the upper 3. This structure of the outer sole assembly 2 provides the latter with great progression in varying hardness between the sides 6, 7. The second sub-portion 72 is provided to be the most flexible entity of the sole assembly 2 in the region of the counter, the first sub-portion 71 to be slightly harder than the second, and the second portion 27 to be harder than the first portion 26, in particular by being harder than the first sub-portion 71.
In any case, the invention is made from materials and according to techniques of implementation known to one of ordinary skill in the art.
The invention is not limited to the embodiments described above, and includes all technical equivalents that fall within the scope of the claims that follow.
In particular, the second portion 27 may not open out on the side of the lower surface 30 and/or on the medial side 7 of the outer sole assembly 2. In other words, the second portion 27 may be embedded or inserted into the first portion 26, in the vicinity of the medial side 27.
In addition, the outer sole assembly 2 may include other layers that are not present in the embodiments described.
The invention disclosed herein by way of exemplary embodiments suitably may be practiced in the absence of any element or structure which is not specifically disclosed herein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 11 02915 | Sep 2011 | FR | national |
This application is based upon French patent application Ser. No. 11/02915, filed Sep. 26, 2011, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is claimed under 35 USC §119.
