# Patent

## Title
For a shoe, in particular for a sports shoe

## Abstract

The invention relates to a shoe in which the specific characteristics of the midsole, namely the width, length, thickness and front/rear profile thereof, midsole materials used with a certain type of deformation (Shore hardness and elasticity), and lateral reinforcements emerging from the midsole and surrounding the upper are suitable for increasing in an extremely noticeable manner both the performance (speed and reduced fatigue) and the user comfort (reduced impact on knees, back, leg muscles), for use when jogging or walking on uneven outdoor surfaces, as well as for jogging or walking on roads. Furthermore, the characteristics of the midsole (spike surface and deformation in contact with the ground) improve the safety of the user by providing enhanced grip on sloping terrain, as well as on snow-covered or wet terrain.

## Background
The present invention relates to an improvement for shoes especially for athletic shoes designed to comfortably navigate very irregular terrain, such as for example that found in mountains, particularly descents with rocks, roots or the like.
In known manner, the shoes feature an upper mounted on an outer sole, and one finds in the market a large selection of athletic shoes, so that the user can choose the type of footwear suitable for the intended purpose.
However good, the sophisticated athletic shoes present a number of disadvantages that the shoe of the invention intends to eliminate.
Thanks to the shoe according to the invention and in particular thanks to the geometry of the lower face of the sole, as well as thanks to the volume and nature of this sole, the movement of the foot takes place naturally, and this regardless of the type of terrain, whether uphill, downhill or on flat ground. In fact, thanks to the sole there is continuity of contact and progressively unrolling.
On reading the following description, it will be understood that the benefits mentioned above exist while respecting the natural position of the foot.
One also understands that thanks to its sole, the shoe of the invention performs particularly well in uneven terrain.
We add that thanks to the side edge, the sole achieves excellent lateral stability, protecting also from shocks.



Other features and advantages of the invention will be apparent from the description which follows, in viewing the accompanying drawings which are given as non-limiting examples.
FIG. 1 is a side view of the shoe of the invention.
FIG. 2 is a top view.
FIG. 3 shows the sole in a perspective view.
FIGS. 4A, 4B, 4C are views according to transverse cross-sections A-A, B-B, C-C, respectively.



The shoe of the invention bearing the general reference 1 comprises in a known manner an upper 2 mounted on an outer sole 3.
The upper is constituted by a shoe box 4 in which the foot of the user is retained. Thus, this upper which is made for example with a flexible material has substantially the shape of the foot of the user, and includes retaining means such as for example a lace.
According to one characteristic, the upper 2 is mounted on the outer sole 3 for it to be secured to its lower part. The upper is of course secured to its sole by any suitable means known such as gluing and the like and is retained by its lower part by a peripheral rim 5 made up of a wall extending upwards surrounding therefore the lower part of the upper. In other words, the sole comprises a central basin 6 constituted by a hollow contour open towards the top for receiving the upper, said hollow being formed by the peripheral rim.
Note that at the level of joining with the sole, the upper cross-section presents widths L1 according to these same cross-sections, the width of the sole at the level that is supported on the ground has widths L2 greater than the width L1 of the upper.
Thus, according to one characteristic of the shoe of the invention the ratio between the value of the width L2 of the sole at the level that is supported on the ground relative to the width L1 is a coefficient K1 between 1.5 and 1.8.
Furthermore, the sole has a thickness H1 comprised between 20 mm and 55 mm while the height H2 for receiving the upper in the sole is between 20 and 30 mm.
In addition, we note that according to an additional characteristic the side wall 7 of the sole is curved to reach the high point 7a from the low point 7b as can be seen in FIGS. 4A, 4B, 4C.
Additionally, the lower surface 8 of the sole comprises a substantially flat central portion 9 extended at the front by a curved raised front portion 9a, and to the rear by a curved raised rear portion 9b. 
Note that the central portion 9 extends over a length L3 whose value is between 40 and 70% of the value of the total length L of the sole.
Know that the length L4 of the curved raised front portion 9a has a value between 25 and 40% of the value of the total length L of the sole, while the length L5 of the curved raised rear portion 9b has a value between 15 and 30% of the value of the total length L of the sole 3.
Also note that the height H3 which the curved raised front portion 9a is raised has a value between 30 and 40% of the length L4 of this same raised front portion 9a. 
Moreover, one will note that the substantially flat central portion 9 extends in part rearward of the point of support 10 of the heel and in part forward from this point, as far as the metatarsals.
One also notes that the height H4 which the raised rear portion 9b is raised has a value less than the value of the height H3 that the raised front portion 9a is raised.
Advantageously, the sole is made of material such as EVA (ethylene vinyl acetate copolymer) whose Shore “D” hardness is for example between 50 and 70.
In this regards the thickness of the sole, for a shoe of sole length L of about 300 mm, the latter is at the level of support of the heel H1c between 30 and 55 mm, and at the level of the forefoot H1a between 20 and 40 mm. This means that the height H1a is between 5 and 15% of the length L and that the height H1c is between 10 and 20% of the length L.
It is well understood that the invention is not limited to the embodiments described and shown as examples, but also includes all technical equivalents and combinations thereof.

## Claims

1. A shoe which comprises: an upper mounted on a sole with a sole length; a thickness of the sole at the level of supporting a heel is between 10% and 20% of the sole length, a thickness of the sole at the level of a forefoot is between 5% and 15% of the sole length and a thickness of the sole in a central portion between the heel and the forefoot is substantially uniform, said central portion having a bottom surface that is substantially flat.

2. The shoe according to claim 1, wherein the sole is made of a material with a Shore “D” hardness between 50 and 70.

3. The shoe according to claim 1, wherein the sole is made of ethylene vinyl acetate copolymer.

4. The shoe according to claim 1, wherein a cross-sectional width of the sole at a level resting on the ground is greater than a width of the upper, and in that a ratio between the cross-sectional width of the sole at the level resting on the ground relative to the width of the upper is between 1.5 and 1.8.

5. The shoe according to claim 1, wherein the upper has a lower part encased by said sole and retained by a peripheral rim of the sole constituted by an upward extending side wall surrounding the lower part of the upper, said sole comprising a central basin for receiving the upper, said central basin being formed by the peripheral rim.

6. The shoe according to claim 5, wherein the sole has a thickness between 20 mm and 50 mm and a height of encasement of the upper in the sole is between 20 and 30 mm.

7. The shoe according to claim 5, wherein the side wall of the sole is curved to join a high point of the sole to a low point of the sole.

8. The shoe according to claim 1, wherein a lower surface of the substantially flat central portion of the sole extends to the front by a curved raised front portion, and extends to the rear by a curved raised rear portion.

9. The shoe according to claim 1, wherein the central portion extends over a length of between 40 and 70% of the sole length.

10. The shoe according to claim 8, wherein a length of the curved raised front portion is between 25% and 40% of the sole length.

11. The shoe according to claim 8, wherein a length of the curved raised rear portion is between 15% and 30% of the sole length.

12. The shoe according to claim 10, wherein a height which the curved raised front portion is raised is between 30% and 40% of the length of said raised front portion.

13. The shoe according to claim 12, wherein a height which the rear portion is raised is less than the height that the raised front portion is raised.

14. The shoe according to claim 13, wherein the substantially flat central portion of the sole extends to a point partly rearward of the heel to a point forward of the heel.