FOOTWEAR HAVING IMPROVED WALKING COMFORT

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon French patent application No. 10/02467, filed Jun. 11, 2010, the disclosure of which is hereby incorporated by reference thereto in its entirety, and the priority of which is hereby claimed under 35 U.S.C. §119.

BACKGROUND

1. Field of the Invention

The invention relates to footwear, especially walking or sports shoes. Shoes of this type may be used in fields such as walking, running on flat and mountainous terrain, as well as sports shoes for urban use, the practice of indoor sports such as squash and volleyball, and for the practice team sports such as soccer and handball.

2. Background Information

For the intended uses, a shoe should have a certain flexibility. This means that the shoe must be capable of adjusting to certain deformations of the foot. This includes allowing a good rolling movement of the foot while walking. The foot undergoes substantial deformation in its rolling movement when the heel is raised from the ground, as well as when flexing in the area of the metatarsus.

A shoe should also retain the foot so as to prevent undesirable foot movements relative to the sole assembly or to the upper in order to avoid risks of injury and to have good precision of placement of the shoe—and the foot within the shoe—during successive landings with the shoe during walking and running. Consequently, the shoe should tighten the foot adequately, while preserving a satisfactory comfort.

A shoe should also have good damping capability, which is intended to reduce or even prevent fatigue and injuries that may result from being supported on the ground and/or from impacts on the ground, as well as from various other forces and biases.

Conventionally, a shoe includes a footwear element, which has a lateral side and a medial side demarcating a rear opening for inserting the foot, as well as a front opening arranged in the area of the instep and extending toward the metatarsus of the wearer. The front opening is sometimes blocked by a tongue. A tightening device is conventionally used to reversibly tighten the upper. Such tightening device may include one or more lace strands that run from one side to the other, in the area of the front opening.

The footwear element also has a vamp, which joins the lateral and medial sides between the front opening and a front end of the shoe. The vamp conventionally covers the toes of the wearer.

In practice, the rolling movement of the foot, as the wearer runs or walks, causes substantial deformations to the shape or morphology of the foot. In a number of regions, such as that of the metatarsus, a transverse cross section of the foot has its height decreased and its width increased simultaneously, and vice versa, during a walking/running cycle. Furthermore, the volume of the foot generally increases during an intense or prolonged exercise. This is the case, for example, when running over long distances or for a prolonged period of time. This practice leads to both fatigue and a general increase in the volume of the foot, a phenomenon that adds to the variation in the transverse cross section mentioned above.

It has also been observed that the magnitude of the variations varies from one individual to another.

Known shoes generally offer a compromise with respect to the rigidity of the footwear element, in order to reconcile the need to ensure optimum support of the foot and the need not to bruise the foot during variations in its volume. Thus, the lateral side, the vamp, and the medial side of a shoe are structured to cover the foot evenly. Therefore, the shoe supports the foot correctly, which means that the transmission of steering impulses or sensory information is accurate.

However, a shoe of this type has been shown to not necessarily provide all of the desired comfort. In particular, the foot is sometimes overly tightened or bruised by folds formed as the footwear element flexes, in the area of the metatarsus, or in the area of the articulations between the metatarsus and the toes. This means that the shoe is not comfortable or is less comfortable that it should be. The prior art has proposed solutions to overcome these problems.

For example, the shoe disclosed by the document EP 082 824, includes an elasticized vamp, meaning that the portion of the footwear element located in the area of the toes and of the metatarsus is capable of becoming elastically and reversibly deformed. This shoe adapts easily to the foot and provides the latter with increased comfort. However, foot support is insufficient in the sense that the transmission of information related to the use of the shoe is modified or insufficient.

To summarize the prior art, one can say that certain shoes provide good support but lack comfort, and that, conversely, other shoes are more comfortable but offer inadequate foot support, at least in certain configurations. In other words, none of the known shoes can reconcile, with enough optimization, the two contradictory characteristics which are foot support, in terms of accuracy, on the one hand, and comfort, in terms of preventing injuries, blisters, etc., but also in terms of constancy through the duration of use, on the other hand.

SUMMARY

The invention improves upon footwear of the prior art, particularly with regard to the foregoing. Thus, the invention reconciles two contradictory characteristics, which are (1) foot support or accuracy of the transmission of information between the foot and the shoe, and (2) comfort of the foot within the shoe or article of footwear. Comfort must be considered in all phases of use, that is to say, irrespective of the intensity of the impulse forces and irrespective of the duration of use. This involves, for example, taking into account the natural deformations of the foot during rolling movements or during flexing support, in combination with the general variation in its volume during intense or prolonged use.

To this end, the invention provides a shoe including an outer sole assembly and an upper, the shoe extending along a longitudinal direction, from a rear end to a front end, along a transverse direction, between a lateral side and a medial side, and heightwise, between the outer sole assembly and a top portion, the upper including a vamp.

The upper of the article of footwear according to the invention includes at least one portion that is structured to deform elastically and reversibly, so that the deformations are controlled. Foot support and comfort are thus improved.

According to a particular embodiment of the invention, the vamp includes a rear portion structured and arranged to cover the metatarsus of the wearer's foot, a front portion structured and arranged to cover the toes, and an intermediate portion structured and arranged to cover the junction between the toes and the metatarsus of the wearer's foot, the intermediate portion connecting the rear portion to the front portion and extending from the lateral side to the medial side, the intermediate portion being structured to deform elastically and reversibly, so that the deformations are controlled.

The intermediate portion is a transverse section of the upper having greater elasticity than the rear and front portions. Between the rear and front portions, the intermediate portion exerts return forces that are proportional to the forces to which it is subjected by accompanying the deformations of the vamp. The intermediate portion, due to its elasticity, prevents folds or hard spots from forming between the front and rear portions, which saves the foot from bruising.

The intermediate portion exerts an elastic constriction on the foot, transversely in the area of the articulations between the toes and metatarsus. Thus, this transverse section of the foot may deform while being constantly retained, that is to say without temporary excess tightening and without temporary loosening. This reduces fatigue, especially during prolonged use, and also reduces or even eliminates any risk of injury.

The intermediate portion forms a uniform connection between the rear and front portions, as opposed to a connection which, were it not elastic, would create folds. This promotes relative movements between the rear and front portions, especially when the shoe flexes, which occurs during foot rolling movement.

Generally speaking, one can say that the shoe of the invention provides both good foot retention and comfort. In particular, in the area of the articulations between the toes and the metatarsus, the support between the vamp and the foot remains within a range of values that are close to one another, in terms of intensity, during the various phases of use of the shoe, resulting in a constant comfort.

BRIEF DESCRIPTION OF DRAWINGS

Other characteristics and advantages of the invention will be more apparent from the description that follows, with reference to the annexed drawings illustrating, by way of non-limiting embodiments, how the invention can be embodied, and in which:

FIG. 1 is a perspective view of a shoe at rest according to an embodiment of the invention;

FIG. 2 is a top view of the front portion of the shoe of FIG. 1;

FIG. 3 is a side view of the shoe of FIG. 1 at rest;

FIG. 4 is a cross-sectional view of the shoe of FIG. 1;

FIG. 5 is a transverse cross-sectional view of the shoe of FIG. 1, in the area of its intermediate portion;

FIG. 6 is an enlarged detailed view of FIG. 4;

FIG. 7 is a side view of the shoe of FIG. 1 during a rolling movement;

FIG. 8 is a top view of the front portion of the shoe of FIG. 7, i.e., in a working phase;

FIG. 9 is an enlarged view of a subdivision of an intermediate portion of the vamp, in the case in which the shoe is at rest; and

FIG. 10 is similar to FIG. 9, in the case in which the shoe is in a working phase.

DETAILED DESCRIPTION

FIG. 1 illustrates an embodiment of a shoe according to the invention, which is structured and arranged as a shoe 1 for walking and running. The shoe includes an outer sole assembly 200 and an upper 300. The shoe 1 extends along a longitudinal direction L, from a rear end 2 to a front end 3, along a transverse direction W (see FIG. 2), between a lateral side 4 and a medial side 5, and heightwise, between the outer sole assembly 200 and a top portion 6.

While reference is made to a shoe for convenience in this description, the footwear of the invention is not intended to be limited by the use of such term, unless otherwise disclosed herein, and applies to footwear that might be referred to as boots and to other articles of footwear, including footwear having a low upper, a mid-upper, or a high upper, for example.

The upper 300 of the shoe of the illustrated invention includes a vamp 305 (see FIG. 8, for example), which is structured and arranged to cover the foot from the instep to the toes. The vamp 305 includes a rear portion 340 for covering the metatarsus of the foot, a front portion 310 for covering the toes, and an intermediate portion 320 for covering the junction between the toes and the metatarsus of the foot. The intermediate portion 320 connects the rear portion 340 and the front portion 310 of the upper. The intermediate portion 320 includes a more or less extensible textile layer 323 obtained, for example, by knitting. The intermediate portion 320 also includes an elastic membrane 321, provided to stretch reversibly, that is, the membrane is elastically stretchable. A deformation control portion, as described further below, comprises the textile layer 323 and the elastic membrane 321. The textile layer 323 and the elastic membrane 321 are superposed (see, for example, the cross section of FIG. 4) and extend continuously from the lateral side 4 to the medial side 5 of the shoe. More specifically, the layer and the membrane 323, 321 extend from one side to the other in the area of the outer sole assembly 200, that is, over 100% of the intermediate portion 320 along the transverse direction W, or substantially therealong. However, in the context of the invention, the layer and the membrane 323, 321 can extend between 80% and 100% of the intermediate portion. It is to be understood that the intermediate portion 320 has greater elasticity than the elasticity of the front portion 310 and the rear portion 340 of the upper. This means that the intermediate portion 320 more greatly elongates for a force of the same intensity.

The intermediate portion 320 is oriented transversely, that is, along the direction W perpendicular to the longitudinal direction L of the shoe, or substantially along such direction. In this regard, and within the context of the invention, it is however within the context of the invention that the intermediate portion can be oriented along an angle ranging between 90° and 120° relative to the longitudinal direction L.

To optimize its role, the intermediate portion 320 is arranged so that its elasticity is controlled. More precisely, the elasticity is damped and therefore controlled, in order to avoid undesired variations in size. In this case, the textile layer 323 and the elastic membrane 321 are affixed to one another, for example by means of glue.

The role of the elastic membrane 321 is comparable to that of a spring, whereas the role of the textile layer 323 is similar to that of a damper, the latter filtering impulses and extraneous information.

A shoe of this type makes it possible to ensure a continuous contact in the area of the junction between the toes and the metatarsus, such junction having a very large variation in its cross section during foot rolling movement, as shown in FIG. 8. This contact ensures foot support without compromising the comfort of the user, for all positions of the foot rolling movement. Foot support is also optimized by the lower elasticity of the front portion 310 and the rear 340 portion, in zones of the foot that undergo less deformation in cross section.

FIG. 1 is a perspective view of an embodiment of the shoe 1 of the invention at rest. FIGS. 2 and 3 are top and side views, respectively, of the shoe 1 of FIG. 1, in this same resting position. As described above, the shoe 1 extends lengthwise along the longitudinal direction L, between the rear end 2, or heel, and the front end 3, or tip. The shoe 1 extends widthwise along the transverse direction W, between the lateral side 4 and the medial side 5.

The shoe 1 includes an outer sole assembly 200 and an upper 300 fixed to the sole assembly 200. The sole assembly 200 is structured and arranged to be interposed between the ground and the foot of the user. The upper 300 is structured and arranged to cover the foot of the wearer and to ensure its contact against the sole assembly 200.

The vamp 305 of the upper 300 includes a front portion 310 structured and arranged to cover the toes. The vamp 305 also has the rear portion 340 structured and arranged to cover the metatarsus and the instep. An opening 341 is arranged in the rear portion 340 to allow insertion of the foot within the shoe 1. The vamp 305 further has the intermediate portion 320 adapted to cover the junction between the toes and the metatarsus of the foot. The intermediate portion 320 connects the rear portion 340 and the front portion 310 of the upper 300, that is to say, of the vamp 305.

The sole assembly 200 is transversely demarcated by the medial side 5 and the lateral side 4. The rear portion 340 has a medial wall 343 extending from the medial side of the sole assembly 200, and a lateral wall 342 extending from the lateral side of the sole assembly 200. The lateral wall 342 and medial wall 343 are connected at the rear of the opening 341. The shoe 1 is adapted to facilitate walking or running and thus has a sole assembly 200 having sufficient flexibility to bend about a transverse axis of the shoe. The sole assembly 200 thus enables a rolling movement of the foot via support of the tip 3, or front end, on the ground and via separation of the heel 2, or rear end, from the ground.

As shown in FIGS. 4 and 6, the upper 300 has an inner envelope including a lining textile layer 360 and an outer envelope. The lining 360 is juxtaposed to the outer envelope, but not fixed thereto. A slight relative slip between the lining 360 and the outer envelope is therefore possible. However, the lining 360 can be fixed to the envelope, using any expedient such as stitching, glue, or the like. As seen in detail more precisely in the cross-sectional view of FIG. 4, the outer envelope includes the textile layer 323 and the elastic membrane 321 of the intermediate portion 320. The textile layer 323 is made of a knitted material, for example. Thus, the textile layer 323 includes thread strands that form a lattice. The layer is capable of becoming deformed, for example, by extending. In doing so, the strands rub against one another, thereby creating a damping effect. The thread strands are made of any suitable synthetic material, such as polyethylene, or the like.

The elastic membrane 321 is similar to a sheet made of a reversibly deformable material, much like a spring. As examples, the membrane 321 can be made of polyurethane, rubber, or any equivalent material.

It is to be understood that the textile layer 323 and the elastic membrane 321 are superposed. More specifically, the layer 323 and the membrane 321 are assembled to one another, for example by hot bonding. Other means can be used within the scope of the invention, including cold bonding. As a result, the textile layer 323 and the elastic membrane 321 cooperate with one another to provide the intermediate portion 320 with an ability to deform elastically in a controlled fashion. The membrane 321 acts as a return spring, in the sense that it seeks to reassume its initial shape when it is biased in extension. The textile layer 323 accompanies the elastic deformations of the membrane by damping them via friction of the threads. The membrane 321 covers the textile layer 323 in the sense that the membrane 321 is on the outer surface of the upper, the textile layer 323 being positioned farther inward of the upper. The membrane could be said to overlie the textile layer.

The intermediate portion 320 thus configured has greater elasticity than the elasticity of the front portion 310 and greater than the elasticity of the rear portion 340.

The intermediate portion 320 could be said to form an elastic arch above the junction between the toes and the metatarsus. The intermediate portion 320 thus closely follows the section of the foot during its rolling movement, despite the very substantial variations in this section over time along the transverse and vertical directions. The user thus has the sensation of uninterrupted contact with the intermediate portion 320. Moreover, the pressure of the intermediate portion 320 on the foot develops gradually during the foot rolling movement due to the elasticity, so that comfort in the shoe 1 is particularly noticeable. The textile layer 323 is capable of undergoing substantial deformations to adjust to the contours of the foot, especially due to its texture. The elastic membrane 321, when situated away from its resting position, makes it possible to return the intermediate portion 320, and in particular the textile layer 323, to their resting positions. The membrane 321 also reduces the folds of the intermediate portion 320 that might otherwise bruise the foot. The intermediate portion 320 further enables the shoe 1 to provide a better adaptation for users suffering from bone deformations in the area of the big toe.

As shown in the drawings, the membrane 321 is fixed to the textile layer 323, for example by heat sealing. As shown in more detail in FIGS. 9 and 10, the membrane 321 advantageously has openings 322 exposing the textile layer 323. These openings 322 are sized to adjust, that is, to control, the elasticity of the intermediate portion 320. Indeed, an increase in the number of openings, or an increase in their size, results in a reduction of the active surface of the elastic membrane 321. In other words, increasing the number of openings reduces the elastic return capability of the membrane 321. Consequently, it is the characteristics of elasticity of the outer envelope that are adjusted. By varying the size of the openings, one can control and adjust the elasticity of the assembly comprised of the textile layer 323 and the elastic membrane 321. In any case, the intermediate portion 320 retains the foot under all circumstances.

Further, the textile layer 323 is advantageously air breathable. The openings 322 facilitate the evacuation of perspiration from within the shoe 1. The openings 322 also facilitate the evacuation of air out of the shoe during foot rolling movement, especially when there is perspiration in the shoe.

According to the structure described, the openings 322 are hexagonal in shape. However, other shapes, such as circles, oblong-shapes, triangles, squares, rectangles, diamond-shapes, and the like, can be used.

The loss of contact between the upper 300 and the foot can thus be avoided by preventing the formation of an air pocket in the area of the intermediate portion 320.

To ensure optimum foot rolling movement while preserving the contact, such as in FIG. 7, the intermediate portion 320 advantageously has a width greater than 5 mm along its entire length, between the medial side and the lateral side of the sole assembly 200. The width of the intermediate portion 320 is measured along the longitudinal direction L of the shoe, whereas its length is measured along the transverse direction W. The width of the intermediate portion is variable, the intermediate portion 320 being narrower in the area of the top portion 6.

As illustrated in FIG. 4, the intermediate portion 320 is fixed to the front portion 310 and the rear portion 340 by respective stitchings 361 and 362. The front portion 310 has a textile layer 316. The rear portion 340 has a textile layer 345. Advantageously, the membrane 321 covers the lines of stitching 361 and 362 of the textile layers 316 and 345. The membrane 321 advantageously makes it possible to hide the stitchings 361 and 362 and to protect them from wear. The textile layers 316 and 345 are structured so that their extension capability is less than the extension capability of the textile layer 323 of the intermediate portion 320.

Advantageously, the textile layer 316 of the front portion 310 has one or more zones 312 not covered by the membrane 321. A zone 312 extends in particular in the median portion of the front portion 310. During rolling movement of the user's foot, this zone 312 can have folds instead of the intermediate portion 320, the toes being less sensitive to a possible loss of contact with the upper 300.

The membrane 321 advantageously has portions extending continuously from a front end to a rear end of the textile layer 323, along the longitudinal direction L of the shoe. These portions make it possible to exert an axial return force on the textile layer 323. These portions thus demarcate the openings 322.

The membrane 321 advantageously has portions 311 and 313 forming a belt that extends downward of the front portion 310. The belt formed thus provides water-tightness to the lower zone of the front portion 310, the one most likely to be in contact with water. The portions 311 and 313 can extend continuously from the edges of the sole assembly 200.

The front portion advantageously includes a relatively rigid end piece 314, protecting the foot and the textile layer 316. The sole assembly 200 further has a tongue 204 that covers the front end of the end piece 314, in order to protect it against abrasion.

The membrane 321 advantageously includes a bridge 315 extending transversely across the front portion 310. This bridge 315 can be provided to exert a force for returning to a position of the shoe 1 corresponding to a slight rolling movement of the foot. To this end, the bridge 315 can have one end affixed to the shell 314. The bridge 315 is not mandatory, and the shoe can be made without it.

The membrane 321 can be made as a film having a thickness between 0.1 and 0.8 mm. Such a film can be made of polyurethane, polyvinyl chloride, silicone, or the like, for example.

The textile layer 323 has a thickness between 0.5 and 3 mm; thickness values ranging from 0.5 to 1.5 mm yield good results. The constituent fibers of the layer 323 are made of synthetic material such as polyurethane, polyethylene, nylon, or any equivalent. The fibers of the layer 323 are woven, for example, to allow its deformation, especially in extension; this may involve knitting the fibers, for example. As a result, the layer 323 resembles a knitted fabric.

Finally, for the same bias in a direction of elongation, or extension, the intermediate portion 320 elongates or extends at least 1.5 times more than the front portion 310 or the rear portion 340. For example, the intermediate portion 320 is provided to elongate 2 to 4 times more than the front portion 310 and the rear 340 portion.

The elasticity of the intermediate portion 320 is primarily defined by the materials and the geometry of the membrane 321 and of the textile layer 323. In the intermediate portion 320, the lining 360 is juxtaposed to the outer envelope without being fixed thereto. Thus, the lining 360 does not interfere with the elasticity of the intermediate portion 320.

According to the illustrated embodiment, the rear portion 340 has a front opening 370, which extends the foot insertion opening 341 forward, between the lateral wall 342 and the medial wall 343.

The front opening 370 in this case is demarcated toward the front by the intermediate portion 320. A separation between the front opening 370 and the intermediate portion 320 could alternatively be provided. The opening 370 is blocked by a tongue 500 fixed via its lower end 371 to the upper 300. The tongue 500 is not mandatory and a shoe can be provided not to have a tongue. A mechanism for reversibly tightening the upper 300 is also provided. This mechanism includes, for example, a lacing device 400 that is arranged vertically above the opening. The lacing device 400 conventionally includes a lace 402 extending through eyelets and loops 401 arranged on the edge of the walls 342 and 343. It is also possible not to equip the shoe 1 with a lacing device 400. In such a case, the rear portion 340 is continuous, from the lateral wall 342 to the medial wall 343.

To ensure optimum foot support, the textile layer 345 of the rear portion 340 is advantageously covered with a frame 344 made, for example, of a synthetic material. For example, the frame includes subdivisions of plastic material or is made entirely of plastic material. The frame 344 in this case is a unitary element, but could alternatively be made in a plurality of subdivisions. The frame 344 stiffens the rear portion 340; and it is fixed to the textile layer 345, for example by gluing or any equivalent means.

FIG. 5 is a transverse cross-sectional view of the shoe 1, in the area of the intermediate portion 320. The upper 300 is fixed to an inner sole assembly 203 by any known technique to form a footwear element. In this case, the upper 300 is affixed to the sole assembly 203 by stitches 363, such as by using the Stroebel technique. The footwear element is then affixed to the outer sole assembly with glue. However, alternatively, the upper 300 can be associated to the inner sole assembly 203 by gluing, or to provide a the two in a nesting configuration. The inner sole assembly 203 can also include an additional insole, not shown. The footwear element is fixed to the outer sole assembly by gluing, using a layer of glue. The outer sole assembly shown includes a plurality of layers. The outer sole assembly includes an outsole 201 and a damping layer 202. The outsole 201 is structured and arranged to come into contact with the ground in order to maximize the adherence of the shoe 1 and to limit its wear. The outsole 201 can include rubber or any abrasion-resistant material. The damping layer 202 includes a highly deformable material, such as a foam of ethyl vinyl acetate (EVA) or any other suitable material, to absorb impacts during contact of the sole assembly 200 with the ground. As illustrated in FIG. 5, the medial side and lateral side of the sole assembly 202 have a lip 205 forming a junction with the upper 300. The lip 205 makes it possible to increase the surface of contact with the upper 300, which increases the useful surface for affixing the footwear element to the outer sole assembly and the useful surface for shock absorption.

The invention is made from materials and using implementation techniques known to one with ordinary skill in the art.

The invention is not limited to the particular embodiments described above and illustrated in the drawing, and includes all technical equivalents that fall within the scope of the claims that follow.

In particular, although the intermediate portion includes two layers, namely the textile layer 323 and the elastic membrane 321, or three if the lining 360 is taken into account, a greater number of layers, for example four or more, can be provided.

Moreover, the portion with controlled elasticity can be provided in other zones of the shoe, for example on only one of the lateral and medial sides of the upper, on a top portion of the upper, without leaving the scope of the invention.

In addition, the invention illustratively disclosed herein suitably may be practiced in the absence of any element which is not specifically disclosed herein.

FOOTWEAR HAVING IMPROVED WALKING COMFORT

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Priority Claims (1)