SHOCK-ABSORBING SYSTEM FOR AN ARTICLE OF FOOTWEAR

Abstract

An article of footwear including an upper overlaying an outer bottom assembly, such assembly including, in the area of the heel, at least two support blocks made of a damping/shock-absorbing material and arranged on respective ones of the lateral and medial sides of the bottom assembly. Each of the support blocks extends vertically, substantially from the upper end to the lower end of the bottom assembly, the support blocks being deformable substantially independently of one another. Further, the outer bottom assembly includes an elastically deformable element that includes an upper portion that extends transversely relative to the bottom assembly and covers the upper end of each of the support elements, as well as at least two legs which extend laterally and medially, respectively, and externally cover respective ones of the support elements, substantially over their entire heights.

Description

BRIEF DESCRIPTION OF DRAWINGS

The invention will be better understood, and other characteristics thereof will become apparent from the description that follows, with reference to the annexed schematic drawings showing several embodiments, by way of non-limiting examples, and in which:

FIG. 1 is a perspective bottom view of shoe including a shock-absorbing bottom assembly according to the invention;

FIG. 2 is an exploded perspective view of the bottom assembly according to the invention, without a contact layer;

FIG. 3 is a side view of the rear portion of the bottom assembly of FIG. 1;

FIGS. 4 and 5 are schematic, transverse cross-sectional views showing the functioning of the bottom assembly in the case of a vertical force;

FIG. 6 is a view, similar to FIGS. 4 and 5, showing the deformation of the bottom assembly in the case of uneven terrain;

FIG. 6 a is a side view of FIG. 6;

FIG. 7 is a view similar to FIG. 2 according to a second embodiment;

FIGS. 8 and 9 are views, similar to FIGS. 3 and 4, relating to the second embodiment;

FIG. 10 is a view, similar to FIG. 2, of an bottom assembly according to a third embodiment;

FIG. 11 is a cross-sectional view along the line XI-XI of FIG. 10;

FIG. 12 is a view similar to FIG. 4 relating to a fourth embodiment;

FIG. 13 is a view similar to FIG. 4 relating to a fifth embodiment;

FIG. 14 is a view similar to FIG. 4 relating to a sixth embodiment;

FIG. 15 is a view similar to FIG. 4 relating to a seventh embodiment;

FIGS. 16 and 17 are bottom views of an bottom assembly according to an eighth and a ninth embodiment, respectively.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 to 6 illustrate the construction and functioning of a shock-absorbing bottom assembly for an article of footwear 1 according to a first embodiment of the invention. The article of footwear 1 shown is a sports shoe, a running shoe in particular, although any other type of sports footwear could, alternatively, be depicted. The shoe 1 is shown in a perspective bottom view in FIG. 1, which shows the tread blocks, or support elements, of the outersole extending upwardly. The shoe 1 includes an upper 2 that overlays an outer bottom assembly 10.

With the expression “outer bottom assembly” or “bottom assembly,” reference is made herein to an assembly of the bottom parts of an article of footwear, i.e., those parts which are positioned beneath the upper, as the article of footwear is worn. In this regard, the outer bottom assembly 10 does not include sole portions such as the insole, midsole, Strobel sole, or lasting insole, which can be directly connected to the upper 2 and/or arranged therein. The upper 2 is fixed to the outer bottom assembly 10 in any known manner, such as by means of glue, stitching, staples, or various expedients known to those skilled in the art.

As shown more particularly in FIGS. 2 and 3, the outer bottom assembly 10 includes, from top down, an upper damping layer 20, or shock-absorbing layer, an elastically deformable element 30, a plurality of damping/shock-absorbing support elements 40 and a contact layer 50 (not shown in FIG. 2 for reasons of clarity).

The upper damping layer 20 extends over the entire length of the bottom assembly 10, or substantially over the entire length, that is, from the rear end to the front end thereof, and includes a front portion 21 and a rear portion 22, respectively, having a uniform thickness, or substantially uniform thickness. The front portion 21 is thicker than the rear portion 22, with a thickness, for example, on the order of 4 millimeters (mm) to 15 mm. The rear portion 22 has a thickness, for example, on the order of 3 mm to 10 mm. In the example shown, the front portion 21 is ended at the rear by a chevron-shaped portion 23, which forms a step in relation to the rear portion 22, and the function of which is explained below. Alternatively, any shape other than the chevron shape 23, such as a wave shape, e.g., can be provided. The upper portion 24 of the upper damping layer 20 is substantially flat/planar or adapted to the shape of the upper. It can also have vertical, or substantially vertical, edges or sides 25 adapted to rise along the upper 2. These edges 25 are higher in the rear zone, especially in the heel zone, and the elastically deformable element 30 includes in the heel area a bowl-shaped portion 31, that is, a portion having a relatively flat bottom 31a that assumes the shape of the upper damping layer 20 and includes edges/sides 31b rising along the upper or the edges 25 of the upper damping layer 20. The bowl-shaped portion 31 further includes a number of projections/legs 33. Included, in the example shown, are two lateral legs 34, two medial legs 35, and a rear leg 36 that are adapted to cooperate with the support elements, as will be described further below. The number of legs could be different depending on the desired result to be achieved according to the invention.

Each leg 34, 35, 36 extends from the rear bowl-shaped portion 31 to the bottom and ends with a return 34a, 35a, 36a, respectively, adapted to be inserted between the damping support elements 40 and the contact layer 50. These returns 34a, 35a, 36a, are essentially adapted to ensure that the legs 34, 35, 36 and the contact layer 50, as well as the support elements 40 adhere properly to one another. The returns can be omitted within the scope of the invention.

In the example shown, the legs 34, 35, 36 are relatively planar/flat and, in the cross-section of the bottom assembly, they are slightly inclined in relation to the vertical direction V (see FIG. 4), adjacent legs being more widely spaced apart at the toward the lower end of the bottom assembly.

Further, as shown in FIGS. 2 and 3, the legs 34, 35, 36 have, in the example shown, a slightly triangular shape that narrows down toward the bottom. Other shapes can be provided depending upon the function of the elastic element. Thus, the legs can be undulated, rather than planar/flat, so as to promote damping in the vertical direction. It is also contemplated, within the scope of the invention, that the legs could extend only over a portion of the height of the blocks.

The elastically deformable element is extended forward by two planar/flat legs 37, the function of which is explained below. The element 30 is made of a relatively rigid and elastic material having a Young's Modulus greater than 40 MPa. It can be made of a synthetic or composite material, such as TPU, PE, reinforced or non-reinforced polyamide, elastomeric polymer (Hytrel®, e.g.), PEBA, carbon/resin fiber-base composite, or other material.

The upper damping layer 20 can be made of EVA or PU foam, with a hardness greater than 20 Asker C, or substantially greater than 20 Asker C.

The damping support elements 40 comprise blocks of damping materials, arranged between the elastically deformable element 30 and the contact layer 50.

In the first embodiment, the support elements 40 are independent and as many as three, namely, a medial block 41 arranged on a medial side of the shoe, two lateral blocks 42, 43 arranged on the lateral side of the shoe. In other words, the support element 41 extends at least on the medial side of a vertical longitudinal median plane and the support elements 42, 43 extend at least on the lateral side of a vertical longitudinal median plane, although the support element 43 extends to or beyond the vertical longitudinal median plane. The medial block 41 is slightly arched so as to follow the contour of the bottom assembly and extends substantially over the entire length of the heel zone of the bottom assembly. This medial block 41 cooperates with the two medial legs 35 of the elastically deformable element 30. The forwardmost lateral block 42 has a substantially paralellepipedic shape and cooperates with only one lateral leg 34 of the elastically deformable element 30. The rearmost lateral block 43 extends on the lateral side and over a portion of the rear of the heel and cooperates with a lateral leg 34 and a rear 36 leg, respectively, of the elastically deformable element. The number of legs could be different for each block, according to the invention.

The lateral block 43 also has the shape of an arc-of-a-circle, or substantially so, so as to assume the contour of the heel.

In the illustrated embodiment, the lateral block 43 has substantially the same length as the medial block 41, but could have a different length. For example, the medial block 41 could be longer. The two lateral blocks 42, 43 are separated by a slit-shaped space 46 that is substantially perpendicular to the edge of the bottom assembly, whereas the medial and lateral blocks 41, 43 are separated by a slit-shaped space 47 that is also substantially perpendicular to the edge or contour of the bottom assembly in the zone considered.

The support blocks 41, 42, 43 are assembled to the elastically deformable element, independently of one another, by their upper ends 41a, 42a, 43a, respectively. In the example shown, the medial block 41 is extended toward the front of the shoe, i.e., beyond the plantar arch, by a slightly thinner damping layer 44 ended by a triangular or chevron-shaped 44d portion that is complementary of that of the front portion 21 of the upper damping layer 20, so as to ensure the shape these two layers fit one another. Alternatively, other forms can be used according to the invention. The thickness of the layer 44 corresponds to that of the step 23 of the chevron. In practice, the blocks 41, 42, 43 are made of elastomerized EVA foam, or PU foam having a 20 Asker C hardness. Indeed, the behavior of such foams is concurrently damping and elastic. As the case may be, more damping foams, such as non-elastomerized EVA foams, can be provided as alternatives within the scope of the invention. In the example shown, the blocks have a vertical thickness ranging from 10 mm to 30 mm, for example, such as 20 mm, or on the order of 20 mm, or a thickness within any range within said range.

The elements 30 and 40 are pre-assembled into a subassembly 60 prior to assembly to the damping layer 20 to form the bottom assembly 10. The arms 37 are housed in recesses 27 of the layer 20 to consolidate the assembly.

As also clearly shown in FIG. 2, each block 41, 42, 43 is provided with one or two recesses 41c, 42c, 43c, respectively, for receiving the associated lug 34, 35, 36 of the elastically deformable element 30. These recesses have shapes that are complementary of those of the associated legs.

Depending upon the embodiment, these recesses could also be omitted.

The contact layer 50 is constituted of rear medial 51, rear lateral 52, 53, and front 54 elements, respectively, adapted to be fixed to the lower ends 41b, 42b, 43b, 44b, respectively, of the support blocks 41, 42, 42, 44, respectively, and of the damping layers 44 and 21, respectively.

The contact layer 50 is made of a wear-resisting material with adherence properties, such as rubber, TPU, or non-abrasive EVA foam, e.g., the latter two materials having the advantage of being lighter than rubber. As the case may be, and depending upon the material used for the support blocks and/or the damping layer, this contact layer 50 can be reduced, or even eliminated.

The combination of an elastically deformable but structurally rigid element 30 and damping support blocks 40 makes it possible to ensure a good damping in all directions, that is, a three-dimensional damping, since the damping blocks 40 are independent, while guaranteeing the stability of the assembly due to the elastic element 30. Furthermore, due to the various shapes of the blocks 41, 42, 43, and to the various numbers/shapes of legs per associated block, the damping characteristics of the blocks can be dissociated between the blocks, on the one hand, and between the vertical and horizontal directions, on the other hand. The functioning of the assembly is shown more particularly in FIGS. 4 to 6.

FIG. 4 shows the bottom assembly 10 according to the invention as laid flat on a ground surface “S”, without any force. In this configuration, the support blocks 40, 41, 43 define a support polygon “P” having a width “l”.

When a force “F” is applied to the bottom assembly in a substantially vertical direction, the support blocks 40 deform and move apart from one another, stressing the elastic element 30, and defining a new, larger support polygon having a width “L” greater than the width “l” of the previous polygon. In other words, the perimeter of the support zone is larger and the stability in the area of the bottom assembly is increased.

As soon as the application of force “F” is discontinued, the elastically deformable element 30 exerts a return force and tends to bring the support blocks 40 back to the initial position shown in FIG. 4. In practice, when a wearer is running, the heel support block 43 is first biased, since it is the first in contact with the ground; then, depending upon the morphology of the user (pronator, supinator), the lateral 42 or medial 41 block comes in contact with the ground, followed by the opposite block, thus causing the spacing apart of the blocks 41, 42.

Because the support blocks 40 are independent, they can therefore deform independently of one another in order to adapt to the foot movement or to the terrain configuration. Thus, in FIGS. 6 and 6a, only the support block 43 and the associated leg 34 deform due to a pebble “P” that is encountered during use of the shoe. This isolated deformation of the support block 43 is, in this case, made possible by the legs, also deformable independently of one another, of the elastically deformable element 30. The construction according to the invention is therefore particularly advantageous for use on loose and uneven terrain.

FIGS. 7 to 9 show a second embodiment in which similar or identical elements are designated by the same reference numerals increased by 100.

In this embodiment, a primary difference, relative to the embodiment described above, resides in the fact that the damping support blocks 141, 142, 143 are connected to one another by a bridge or wall 147 of material. Because the wall 147 is very thin, on the order of 3 mm to 10 mm, relative to the support blocks 141, 142, 143, the latter are always free to move independently of one another. However, the fact that they are connected makes it easier to assemble them.

Furthermore, when a force “F” is exerted on the outer bottom assembly 110, and the latter is compressed by this force, as shown in FIG. 9, the material wall 147 is biased in traction and, when returning, also tends to return the bottom assembly to its original form as soon as the application of force is discontinued.

To enable this elastic return effect of the wall 147, the wall is not adhered to the elastically deformable element 130. Instead, it is separated therefrom by a cavity or space 148.

Another difference between the two aforementioned embodiments is the that the damping blocks 141, 142, 143, 144 are formed as a unitary element.

Finally, the medial support block 141 is made of a material that is similar to that of the remainder of the assembly 140, such as EVA foam, for example, but with a greater hardness, such as between 50 and 65 Asker C, for example. It is also extended to the portion 144 by a portion 144a having the same hardness. Alternatively, the support block 141 can be made of a different material, with the goal of being slightly harder (therefore less damping than the other blocks). This function is also linked to the pronator/supinator type of the shoe.

In the embodiment shown in FIGS. 10 and 11, similar or equivalent elements are designated by the same reference numerals used in FIGS. 7 to 9, increased by 100.

In this case, the damping support elements 241, 242, 243 of the outer bottom assembly are also grouped in a single block 240. Compared to the previous embodiments, where the element 40, 140 stops shortly after the plantar arch, the element 240 here extends up to the area of the shoe corresponding to the metatarsophalangeal articulation zone of the wearer's foot, and is therefore longer.

The extra thick portion 221 of the damping layer 220 is consequently reduced and only extends from the front of the sole to the metatarsophalangeal articulation zone (defined in this case by the step 223). Furthermore, the elastically deformable element 230 has two elongated horizontal arms 237 at the front, which form a sort of fork.

The elongated arms 237, therefore, extend into the metatarsophalangeal articulation zone demarcated by the limits 223, 244d, and make it possible to provide the bottom assembly, in its front zone, with an additional elastic restoration. Furthermore, these arms 237 each include a leg 238 similar to the legs 234, 235, 236, and extend substantially vertically along the front portion 244 of the support block 240.

The vertical legs 238, as is the case with the legs 234, 235, 236, increase the stability of the bottom assembly.

In the illustrated embodiment, the arms 237 and lugs 238 of the elastically deformable element 230 are housed in associated recesses 244e, 244f of the support block, these recesses having complementary shapes and being arranged on the upper surface and the sides, respectively, of the front portion 244 of the support block 240.

FIGS. 12 to 17 show other embodiments of the invention in which the elements are designated by the same reference numeral used in FIGS. 10 and 11, increased each time by 100.

In these various embodiments, the bottom assembly includes at least two support elements, but additional return/stabilization arrangements are also provided.

In the embodiment of FIG. 12, the bottom assembly 310 therefore includes at least two independent damping support elements 341, 343 externally covered substantially over their entire height by an elastically deformable element 330 and provided with a walking sole or contact layer 350.

As in the embodiment of FIG. 8, the support elements 341, 343, while remaining independent, are connected by a material wall 347 made in the same material as the support element 341, 343, making it easier to assemble the bottom assembly, and which also enables a certain elastic return (not visible in the drawing) of the support elements 341, 343, 342 toward one another after compression.

In order to reinforce the elastic return effect, the contact layer 350 is also provided so as to connect the various support blocks 341, 342, 343 and, therefore, includes a material wall 355 connecting these various elements in the area of their lower end. Because the contact layer 350 is made of a very elastic material, such as rubber or any elastomerized material, it enables an advantageous effect of elastic return of the bottom assembly toward the original position.

Such a construction enables an additional stabilizing effect. In practice, this rubber wall 355 makes it possible to avoid up to 5 mm of residual spacing of the blocks after the return to the original position.

In other words, almost any residual deformation that would result in the spacing apart of the blocks is avoided. In practice, a residual deformation of 5 mm to 8 mm is avoided over the width of the sole.

The rubber wall 355 (or any other material) can be provided individually, i.e., independent of the wall 347.

FIG. 13 shows a similar embodiment, in which only the rubber wall 455 is provided.

In this case, the space 460 between two support elements 441, 443, 442 is filled with a material 461 such as EVA, PU, or gel, adapted to avoid having a hole behind the material wall 455. The space 460 can be filled by localized extensions, with a smaller cross section, of the material of the support elements 441, 442, 443, as defined, for example, by the arms 355a, 355b, 355c in FIG. 16 (FIG. 13 then being considered as a cross-sectional view along the line XIII-XIII of FIG. 16), or the arms 355d, 355e of FIG. 17.

In the embodiment of FIG. 14, the space 560 between two support elements 541, 543, 542 is filled by a material 561, such as EVA, PU, gel.

However, a cavity 548 is arranged between the elastically deformable element 530 and the support elements 541, 543, 542 so as to keep the support elements independent, and a material wall 547 made of the same material as the support elements 542, 543, 541, is provided between the latter.

In the embodiment of FIG. 15, an elastic return element 647 extending substantially horizontally is inserted between the support elements 641, 643, 642 in the same manner as in FIG. 8. The only difference lies in the fact that this return element 647 is, in this case, made of a different material, such as elastomeric rubber, for example. This element is further arranged substantially in the median portion, in the vertical direction of the support blocks.

FIGS. 16 and 17 show different embodiments of the bottom of the bottom assembly of FIG. 12 (but also of FIGS. 13 to 14), i.e., in the case where the contact layer 350 includes a material wall 355 between two support blocks 341, 342, 343 to enable an elastic return of these blocks toward one another.

In FIG. 16, the material wall 355 includes three substantially similar arms 355a, 355b, 355c that each extend from a support block 342, 343, 341, respectively, and connect to one another, forming a star shape.

In FIG. 17, the material wall 355 only includes two arms 355d, 355e, respectively, each connecting two support blocks to one another, namely, the blocks 342, 341 and the blocks 343, 341, respectively.

The configuration of FIGS. 16 and 17 can also be applied to the embodiment of FIG. 15. In this case, it is the return element 647 that has a shape made of three arms 355a, 355b, 355c, or of two arms between the support blocks.

In the various embodiments, the number of arms 355a, 355b, 355c or 355d, 355e can be modified and, for example, can be as many as four or more, or less.

The present invention is not limited to the various embodiments described hereinabove by way of non-limiting examples, but encompasses all similar or equivalent embodiments.

Claims

1. An article of footwear comprising: an upper;a bottom assembly beneath said upper, said bottom assembly comprising: an upper end and a lower end;a vertical longitudinal median plane;a medial side of the vertical longitudinal median plane and a lateral side of said vertical longitudinal median plane;a heel area;in the heel area, at least two support elements comprising a shock-absorbing material, said two support elements comprising at least one support element extending at least on the medial side and at least one support element extending at least on the lateral side;each of said two support elements having a height extending substantially from the upper end to substantially the lower end of the outer bottom assembly;each of said two support elements being deformable substantially independently of one another;an elastically deformable element comprising: an upper portion extending transversely with respect to the bottom assembly and covering an upper end of each of said two support elements;at least two legs, a first of said two legs extending at least on the medial side and a second of said two legs extending at least on the lateral side;said two legs extending over an external surface of an entirety of the heights of respective ones of said two support elements.

2. An article of footwear according to claim 1, wherein: the elastically deformable element is affixedly assembled to each of the support elements.

3. An article of footwear according to claim 1, wherein: each of said two legs of said elastically deformable element has a lower end fixed beneath the lower end of a respective one of said two support elements.

4. An article of footwear according to claim 1, wherein: each of said support elements is provided with a contact layer at a lower end.

5. An article of footwear according to claim 1, wherein: said at least two support elements comprises at least three support elements;said at least one support element extending at least on the lateral side comprises at least two support elements extending at least on the lateral side.

6. An article of footwear according to claim 5, wherein: one of said at least two support elements extending at least on the lateral side extends to a rear of the heel area.

7. An article of footwear according to claim 1, wherein: each of said support elements is independently affixed to the elastically deformable element by its upper end.

8. An article of footwear according to claim 1, wherein: the support elements have upper ends;the support elements are affixed at their upper end to the elastically deformable element via a material wall.

9. An article of footwear according to claim 1, wherein: the support elements are assembled together by means of an elastic material wall.

10. An article of footwear according to claim 9, wherein: the elastic material wall comprises a rubber or other elastomeric material.

11. An article of footwear according to claim 10, wherein: the bottom assembly further comprises a walking sole;the elastic material wall extends upwardly from the walking sole.

12. An article of footwear according to claim 9, wherein: the elastic material wall is arranged at lowermost ends of the support elements.

13. An article of footwear according to claim 9, wherein: the elastic material wall is arranged substantially mid-height of the support elements.

14. An article of footwear according to claim 1, wherein: the medial support element has a hardness greater than a hardness of the lateral support element.

15. An article of footwear according to claim 14, wherein: the elastically deformable element comprises, at an upper end, a bowl-shaped portion arranged in the heel area of the bottom assembly.

16. An article of footwear according to claim 15, wherein: the bowl-shaped portion extends up to a plantar arch area of the article of footwear.

17. An article of footwear according to claim 1, wherein: the elastically deformable element is extended forwardly by two horizontally extending arms, a first of the two arms being on the medial side of the vertical longitudinal median plane and a second of the two arms being on the lateral side.

18. An article of footwear according to claim 1, wherein: the bottom assembly further comprises a layer of shock-absorbing material arranged between the elastically deformable element and the upper.

19. An article of footwear according to claim 1, wherein: the two support elements are made of a polymeric foam from a damping material such as EVA, PU.

20. An article of footwear according to claim 1, wherein: the two support elements are made of EVA foam or PU foam.

21. An article of footwear according to claim 1, wherein: the elastically deformable element is made of a material having a Young's Modulus of at least 40 MPa.