WO2007069069A2

WO2007069069A2 - Shoe having a midsole comprising at least a stratified dumping element

Info

Publication number: WO2007069069A2
Application number: PCT/IB2006/003652
Authority: WO
Inventors: Luca Sordi
Original assignee: Freddy S.P.A.
Priority date: 2005-12-15
Filing date: 2006-12-13
Publication date: 2007-06-21
Also published as: ITMI20052393A1; WO2007069069A3

Abstract

A shoe having a sole (1) connected to an upper part (11 A) of the shoe, said sole being of the type having an outer sole (4) able to come in contact with the ground and an intermediate flexible sole (1) fastened to the upper surface of said outer sole, and able to damp the stresses whereto the foot is subjected, said sole (1B) comprising: a part (1B) able to support the forefoot of the foot, and a part (1 A) able to support the heel, at least one of said parts able to support the heel and the forefoot having in the intermediate sole a damping element (10, 11); in which each damping element (10, 11) comprises: at least three layers (11 A-C, 10 A-C) at least partially superposed and fastened to each other, said layers being made of plastic materials having different compressibility features, a first intermediate layer (10B, 11B) being the one made of the material with highest degree of compressibility, a second layer (10 A, 11 A), provided at least partially above said intermediate layer being made of a substantially non compressible material, a third layer (10 C, 11C) provided at least partially underneath said intermediate layer being made of a material having a lower degree of compressibility than the intermediate layer.

Description

Title

Shoe having a midsole comprising at least a stratified dumping element Description

The present invention relates to a shoe according to the pre-characterising part of the main claim.

Shoes of the above type have been known for some time, see for example the patents US4,316,335 or US4,794,707 or US5,933,983 or GB2,388,520 or US 5402 588 or US 6,233846 by the same applicant. While prior art shoes do assure good performance, especially if used within the field of athletics and in particular as running shoes, they have not proven to be equally valid in similar fields, e.g. aerobics and/or modern dance. The latter sporting activities, where jumps are frequently taken, require shoes that are able to absorb the considerable stresses whereto the feet and in particular the heels and the forefoot, and at the same time, they require shoes that, while optimally containing and supporting the foot, are not excessively heavy or rigid.

Moreover, prior art shoes are not always able to optimally absorb the different stresses whereto the different regions of the sole are subjected, and when this purpose is achieved prior art solutions use damping elements that are complicated to manufacture and/or integrated in the sole. The same considerations also hold true for all prior art shoes in which the soles have elements that not only are able to damp stresses but are also able to return at least in part the damped energy to the user's foot.

An object of the present invention is to provide a shoe able to assure an optimal absorption of the stresses whereto the sole of the shoe is subjected and hence to assure an optimal damping effect for the user's foot, and able to compensate for the different stresses whereto different regions of the sole are subjected, and which at the same time assures a manufacture of the sole with a low number of component, in rapid and profitable fashion. An additional object is to provide a shoe that is able to facilitate determined movements of sporting activities and in particular a shoe that has a sole able to return at least partially to the user the energy discharged on the sole itself.

An additional object is to provide a shoe in which the damping features can be appreciated both visibly and by touch by the consumer even when the shoe is not worn, thereby enhancing the marketability of the shoe.

These and other objects which shall become readily apparent to a person skilled in the art are achieved by a shoe in accordance with the features of the characterising part of the main claim. In the accompanying drawings, a shoe according to the invention is shown by way of non limiting example. The drawings show: in Figure 1, a schematic lateral view of a shoe according to the invention, in Figure 2, an exploded schematic view of the intermediate sole of the shoe, in Figures 3 and 4, lateral view, respectively of the inner and outer part, of the sole of a shoe according to the invention, in Figure 5, a schematic plan view of the sole, in Figure 6, a schematic section view taken according to the line A-A of Figure 5 of the sole, in Figure 7, a schematic section view taken according to the line B-B of Figure 5 of the sole, in Figure 8, a schematic section view taken according to the line C-C of Figure 5 of the sole, in Figure 9, a schematic top view of the sole, in Figure 10, a schematic section view taken according to the line D-D of Figure 5 of the sole.

With reference to the aforementioned figures, a shoe according to the invention comprises a sole 1 connected in conventional fashion for a person skilled in the art, e.g. by sewing and/or gluing, to a usual upper and/or underfoot of the shoe. The upper and the underfoot of the shoe are conventional for the persons skilled in the art and they comprise a plurality of parts IA fastened to each other and usual closing means, which in the example shown in Figure 1 are of the string type, but which could be of any other known type. The sole of the shoe comprises an outer sole 3, able to come in contact with the ground, and an intermediate or midsole 4 able to damp the stresses whereto the foot is subjected. If no underfoot is provided and the edge of the upper is fastened to the sole, e.g. sewed, the shoe comprises a conventional internal insole (not shown) bearing on the upper surface 5 of the intermediate sole, said internal insole is of a conventional type, it is made of conventional flexible materials and it is preferably of the type able to be removably inserted into the shoe from the opening provided for wearing the shoe.

The sole 1 according to the invention comprises two distinct parts: a first one IA which extends and is able to support the heel portion of the foot of the user of the shoe and a second part IB which extends and is able to support the forefoot portion of the foot of the user of the shoe. According to the invention, the intermediate sole 4 (Fig. 2) of the shoe, to damp the stresses whereto the user's foot is subjected, comprises in each of its parts 4A and 4B able, respectively, to support the heel and the forefoot, in the intermediate sole part a damping element, respectively 10 and 11. Each damping element 10, 11 comprises: at least three layers 10 A-C₅ 11 A-C at least partially superposed on each other, made of plastic materials having different compressibility features: a first intermediate layer 1OB, HB being the one made of the material with the greatest degree of compressibility, a second layer 10 A, 11 A provided over said intermediate layer 10 B 11 B being made of a substantially non compressible material, and a third layer 10 C, 11C provided at least partially underneath said intermediate layer 10 B 1 1 B being made of a material having a lower degree of compressibility than the intermediate layer.

The layers 10 B 11 B with greater compressibility are made of any plastic material suitable for the purpose, e.g. EVA or PHYLON having: hardness ranging between 30 and 50 C. The layers 10 C 11 C with lower compressibility, provided underneath the intermediate layers 10 B 11 C, are made of any plastic material suitable for the purpose, e.g. EVA or PHYLON having hardness ranging between 55 and 65 C.

The layers 10 A and 11 A, provided at least partially over said intermediate layer 1OB are made of any substantially non compressible plastic material, in relation to the stresses whereto the sole of a shoe is subjected by the action of the foot wearing the shoe; said material is, for example, TPU having hardness ranging between 46 and 50 D (where ID is approximately equal to 30 C). The three layers are mutually fasten in a conventional fashion for the person skilled in the art, e.g. by gluing or co-moulding.

The part 1 A of the sole, able to support the heel, has a U shape with the opening of the U oriented towards the tip of the shoe. More in particular, the part of the intermediate sole of said part IA comprises two U shaped elements 12 and 13 having different dimensions, inserted one inside the other, which respectively embody the layers of the intermediate sole with greater compressibility (U-shaped element 13 with smaller dimensions) and with lower compressibility (U-shaped element 12 with larger dimensions), and a bridge element 14, which embodies the non compressible layer of the intermediate sole, and is able superiorly to close the cavity delimited by the U in such a way that said part IA has, if seen from the bottom, a recess elongated at the central part of the heel, delimited by the arms of the U of the larger sized U-shaped element 12. The larger sized U-shaped element 12 comprises in its interior, at the opening delimited by the arms of the U, a recessed seat 15 able to house the other U- shaped element 13 having smaller size; the two U-shaped elements and the aforesaid seat are so shaped and dimensioned that when the sole is not stressed, they superiorly form a substantially planar surface whereon bears the bridge element 14. The smaller sized U shaped element 13 is able to form the layer of the intermediate sole with higher compressibility. The smaller sized U shaped element 13 has projections 13 A extending from the arms of the U, able to house in two additional lateral seats 12 A provided in the arms of the other U-shaped element 12, dimensioned and shaped in such a way that the ends of the aforesaid projections are viewable and touchable by a user of the shoe who in this way can appreciate both visually and by touch that the intermediate sole comprises two distinct elements having different compressibility features. For this purpose, the two U- shaped elements could advantageously also have different colours. The bridge element 14 comprises a substantially planar portion 14 A able to bear on the upper portion 13 B 12 B defined by the U shaped elements 12 and 13, said surface 14 A comprises, at the heel, a U-shaped slit 17 delimiting a tongue 16, at least partially flexible relative to the remaining part of said support element. According to the invention, the U shaped slit 17 is dimensioned and positioned in such a way that, when the bridge element 14 and when the U-shaped elements 12 and 13 are mutually superposed, the tongue 16 closes the opening delimited by the smaller-sized U-shaped element 13, and bears on the upper face 13 B of said smaller-shaped U-shaped element 13. The bridge element 14 also comprises a part 6 made in a single piece and coplanar with the portion 14 A of the element, able to be positioned in the heel region, said part 6 is able to mutually connect the heel part 1 A and the forefoot part 1 B of the sole of the shoe and to serve as at least a partial support for the plantar arch. This plantar arch support part 6 has a thickness S3 (Fig. 3) that is considerably lower than that of the remaining parts of the sole, both with respect to the heel portion and to the forefoot portion; said thickness S3, measured at a longitudinal section of the sole (Fig. 3) can, for example, be less than or equal to half the thickness values Sl and S2 of the forefoot and heel parts of the sole, measured at the aforesaid section and at the portions of said parts that are in contact with the ground T when the shoe is not worn; preferably, said thickness S3 is approximately equal to ¹A of the lesser thickness between Sl and S2. To enhance stiffness, the sole part 6 at the forefoot has projecting portions 6A able to increase the thickness S3 and, consequently, enhance its rigidity, said portions advantageously have a profile that is substantially parallel (Fig. 5) or slightly arched with respect to a longitudinal line L of the sole, thereby creating ellipses or semi- ellipses with the longer axis coinciding with the longitudinal axis of the shoe. Advantageously, moreover, the bridge element 14 for the heel and its part 6 for the plantar arch have a raised edge 20 able to protect, contain and laterally support the lower lateral part of the foot in proximity to the planar arch and of the heel, said raised edge is preferably a continuous wall that extends from one side of the plantar arch to the other passing through the heel, with an undulatory profile with increasing height from the forefoot to the central part of the plantar arch and then with decreasing height at the heel. According to the invention, the tongue 16 is so shaped and sized that, when the shoe is worn, it is substantially underneath the user's heel bone. In this way, the weight of the user of the shoe is concentrated in the portion of the intermediate sole provided between the edge of the tongue 16 and the surface of the U-shaped element 13 whereon said edge bears, and hence it is transferred to the bearing portion between the U-shaped element 13 and the U-shaped element 12. Thanks to the sole according to the invention, the stresses of the heel are first damped by the layer 1OB, of the U-shaped element 13, having higher compressibility, and then further damped by the second layer 1OC, of the U-shaped element 12, having lower compressibility, thereby assuring a more gradual and better absorption of the stresses on the heel. The stresses caused on the heel part of the sole, e.g. by landing after a jump also cause a downward flexion of the tongue 16, which is damped by the compressible layers 10 B and C as described above, the aforesaid layers and the tongue itself tend, however, to return to their non-compressed state when the force that compressed them ceases or diminishes, and this favourably causes at least a part of the energy discharged on the sole to be returned to the foot, which return facilitates the sporting activity.

It should be stressed that this return of the energy discharged on the sole is enhanced by the presence of the tongue 16, by the fact that the material constituting the element 14 in which said tongue is obtained, while it is not compressible, is elastic, and by the fact that the tongue bears on a layer 1OB made of highly compressible material and only indirectly on a layer 1OC with lower compressibility.

It should be stressed that the layer 1OC is made of the compressible material whereof intermediate soles had heretofore always been made and that the invention consists of having thought of adding an additional, more compressible layer, over said usual material.

Advantageously, as shown in Figure 7, the flexible bridge part 16 has along its lower surface a bulge 16 A, able to provide the element with a variable cross section, i.e. thicker at the centre (Tl) than at the edges (T2) that come in contact with the U-shaped element 13.

Advantageously, the tongue 16 of the bridge element 16 has on its lower surface a projection 6C (Fig. 7) extending in contact with the wall of the cavity delimited by the arms of the U of the heel part of the sole, and able to assure an ever-optimal centring of the tongue itself. Advantageously, to improve the features of compressibility and damping of the stresses whereto the heel part of the intermediate sole is subjected, the U-shaped element 13 has a plurality of recesses or through holes 21, said recesses or through holes can also be provided in the other U-shaped element 12 as shown in Figure 7. To the lower face of the U-shaped element 12 having greater size and lower compressibility is conventionally applied, e.g. by gluing or co-moulding, a conventional outer sole 23, e.g. made of rubber, able to come in contact with the ground, said sole leaves free the cavity defined by the U-shaped elements of the intermediate sole and it advantageously has in its portion provided in the inner side of the shoe a plurality of slits 23 B and recesses 23 A able to improve the adherence of the sole. The forefoot part 1 B of the sole has, as in the previous case, an intermediate sole 4 (Fig. 2) and an outer one 24 fastened for example by co-moulding or gluing. The intermediate sole 4 has a main support body 25 extending throughout the surface of the forefoot, but excluding the plantar arch, in the central part of said main body 25, at the region of the foot between the phalanxes and the plantar arch is provided a recessed seat 28 able to house a damping element 26 above which is provided a substantially rigid, non compressible, slightly arched element 27 as shown in Fig. 6. The seat 28 and the elements 26 and 27 are so shaped that in a rest situation the slightly arched upper surface 25 A of the body 25 is substantially coplanar with the upper surface 27 A of the element 27 as shown in Figure 6. Advantageously, the seat 28 and the damping element 26 have isosceles trapezoid cross section shape with the smaller base oriented downwards. The damping elements 26, the rigid element 27 and the part 29 whereon said element 26 bears constitute a damping system according to the invention, formed by three layers having different compressibility features: the element 26 is made of the material with the highest compressibility, the underlying part 29 of the body 24 is made, as is the entire body, of a material having lower compressibility than that of the material of the element 26, whilst the element 27 is made of a substantially non compressible and rigid material.

In the forefoot part too, to improve the damping of the stresses whereto this part of the food is subjected, the element 27 does not bear on a continuous surface 26 A of the damping element 26. The damping element 26 has, at its upper surface 26 A whereon the element 27 bears, a deep slit 27 B that provides the element 26 a substantially U- or C-shaped cross section; the element 26 thus has (Fig. 2) two arms 26C extending from a base 26D, and the element 27 bears on the ends of said arms 26C. In this way, the force transmitted from the foot to the intermediate sole in the forefoot part of the shoe provided between the first phalanxes and the plantar arch is concentrated by the rigid element 27 on the arms 26C of the damping element 26 and only subsequently distributed on the additional damping layer defined by the portion 28 of the body 25 of the intermediate sole. The operation and the advantages of the damping structure are those illustrated previously with reference to the heel part of the sole and therefore they shall not be repeated here. As for the intermediate heel sole, also in the case of the forefoot part the element with higher compressibility 26 and the element with lower compressibility 25 are so shaped that at least the ends of the element 26 are visible and touchable from the exterior, so that it can be appreciable that two superposed layers, having different compressibility features, are present also in the forefoot part of the intermediate sole of the shoe. Advantageously, the rigid element 27 also extends to the sides of the sole, in order to be appreciable from the exterior.

Advantageously, to enhance the flexibility and/or the compressibility of the intermediate sole, the body 25 has three transverse slits, whereof two are provided in the region of the phalanxes of the body 25 and three recesses or through holes 31 provided in the part with greater thickness of the body 25 in proximity to the start of the plantar . arch. From each of the sides of the body 25 also extends an arm 7, arched and oriented towards the heel of the shoe able to enhance the lateral stability of the shoe and laterally to connect the forefoot part of the sole with the heel part. The arms 7 are so shaped and dimensioned as to bear and to be able to be rigidly fastened, in conventional fashion for the person skilled in the art, e.g. by gluing or co-moulding, on the raised edges 20 of the rigid part 14 of the intermediate sole provided at the heel.

It should be stressed that the body 25 at its edge oriented towards the plantar arch has a recessed seat 32 able to house the edge oriented towards the tip of the shoe of the rigid planar element 14, which in this way can be more easily and uniformly fastened, in conventional fashion for the person skilled in the art, e.g. by co-moulding or gluing, to the forefoot part of the intermediate sole, thereby achieving a connection between the two parts, forefoot and heel of the intermediate sole, and at the same time assuring a good support but also a good flexibility to the plantar arch. In its portion 6 provided under the plantar arch, the element 14 has, as previously recalled, a very small thickness which assures a good flexibility of the element.

The outer sole 24, made of any material suitable for the purpose, is fastened, in conventional fashion, e.g. by gluing or co-moulding, to the lower surface of the body 25 of the intermediate sole of the forefoot part, but advantageously it does not extend throughout the aforesaid lower surface. To improve the flexibility of the forefoot part of the sole, the outer sole is not provided at two flexion lines 36 A 36 B (Fig. 5), so that, in the forefoot region the outer sole is subdivided into three islands 24 A-C. The outer sole, moreover, is also absent at the inner side of the forefoot sole approximately in the portion between the phalanxes and the plantar arch; in this position, in an area having substantially triangular shape, the outer sole is replaced by a projection 40 of the intermediate sole which remains flush with the adjacent outer sole. This projection 40 is an extension of the body 25 which thereby assures a better adherence and damping in a particularly delicate region of the foot. In this way, it is also possible to reduce the weight of the shoe, since the plastic material of the body 25 has far smaller weight than the plastic material of the outer sole.

A indicated above, the sole 1 according to the invention comprises two distinct parts: a first one IA which develops and is able to support the heel portion of the foot of the user of the shoe and a second part IB which develops and is able to support the forefoot portion of the foot of the user of the shoe. These two distinct forefoot and heel parts IA and IB of the sole 1, in the illustrated example, are joined together by the extension 6 of one of the components of the heel part of the intermediate sole 4 and, laterally, thus not at the actual sole, by the two lateral extensions 7 of one of the components of the forefoot part of the intermediate sole 4. However, it should be stressed that the scope of the invention includes both a shoe with a sole that has the aforesaid extensions 6 and 7, and a sole that does not have them, said extensions therefore have been indicated with a dashed line in the figures. Depending on the degree of flexibility the shoe is to have at the plantar arch, the shoe may or may not have the sole portion 6, and/or the lateral ones 7, at the plantar arch. It should be stressed that, since the shoe according to the invention is intended in particular for use in sporting activities like aerobics and modern dance, the features of flexibility of the plantar arch are in some cases extremely important. If these portions are absent at the plantar arch, no sole will be provided but only a flexible portion of a lower part or underfoot of the upper, also known as underfoot, of the shoe (as described, e.g., in the patent US6,233,846 by the same applicant). In any case, it should be stressed that according to the invention at the plantar arch the sole does not have an outer sole but possibly only a connecting element belonging to the intermediate sole.

Lastly, it should stated that the embodiment described herein is provided purely by way of example and that the scope of protection of the present invention includes numerous variants, such as a show having a traditional forefoot sole and a damping element as described previously only in the heel part or vice versa.

Claims

1) Shoe having a sole (1) connected to an upper part (11 A) of the shoe, said sole being of the type having an outer sole (3) able to come in contact with the ground and an intermediate flexible sole (4) fastened to the upper surface of said outer sole, and able to damp the stresses whereto the foot is subjected, said sole (1) comprising: a part (IB) able to support the forefoot of the foot, and a part (1 A) able to support the heel, at least one of said parts able to support the heel and the forefoot having in the intermediate sole a damping element (10, 11); characterised in that: each damping element (10, 11) comprises at least three layers (10 A-C, 11 A-C) at least partially superposed and fastened to each other, said layers being made of plastic materials having different compressibility features, a first intermediate layer (1OB, HB) being the one made of the material with highest degree of compressibility, a second layer (10 A, 11 A), provided at least partially above said intermediate layer being made of a substantially non compressible material, a third layer (10 C, HC) provided at least partially underneath said intermediate layer being made of a material having a lower degree of compressibility than the intermediate layer.

2) Shoe as claimed in claim 1 characterised in that the three layers (10 A-C, 11 A-C) are at least partially in mutual contact when the shoe is not worn.

3) Shoe as claimed in claim 1 characterised in that each damping element (10, 11) comprises only three layers having different compressibility features and that each of said three layers is made of a single material.

4) Shoe as claimed in claim 1 characterised in that the sole (1) comprises a part (6) able to support the plantar arch and able to connect the heel and forefoot parts of the sole to each other. 5) Shoe as claimed in claim 1 characterised in that the part (1 A) of the intermediate sole able to support the heel has a central opening delimited by portions of the two compressible and superposed layers (10 B, C) of the sole, said opening being closed by a portion of the substantially non compressible layer (10 A). 6) Shoe as claimed in claim 5, characterised in that a portion of the non compressible layer (10 A) bears on a portion of the first layer (10 B) having greater compressibility which in turn bears on a portion of the third layer (10 C) having lower compressibility than said first layer. 7) Shoe as claimed in claim 1 characterised in that the layer (10 A) made of substantially non compressible material of the damping material provided at the heel comprises a support element (14) made of a substantially non compressible material able to serve as a support at least for the heel, said element (14) comprising at the heel a slit (17) delimiting a tongue (16), at least partially flexible relative to the remaining part of said support element, in that the first and third layer (10 B, 10 C) have, at the heel, a central opening, said tongue closing in bridging fashion said central opening of the sole.

8) Shoe as claimed in claim 7 characterised in that said slit (17) and said opening have substantially the same shape.

9) Shoe as claimed in claim 8 characterised in that said slit (17) and said opening have substantially U shape.

10) Shoe as claimed in claim 7 characterised in that the non compressible support element (14) comprises also a part able to support the plantar arch made in a single piece with the part able to support the heel, said part for the plantar arch being able to mutually connect the parts of the intermediate sole for the heel and for the forefoot. 11) Shoe as claimed in claim 7 characterised in that the support element (14) has an edge (20) that is raised relative to the portion of said element comprising the tongue, said raised edge being able to contain and protect at least partially the part of the foot above the heel and the plantar arch.

12) Shoe as claimed in claim 11 characterised in that said raised edge (20) has a wave- like profile with increasing height from the forefoot to the central part of the plantar arch and then decreasing height at the heel.

13) Shoe as claimed in claim 1 characterised in that the first and the third layer (10 B, C) made of material with different degrees of compressibility, comprise respectively a first and a second damping element (13, 12) having U shape, at the edge of said U of the second damping element (12) being provided a recessed seat (15) able to house said first damping element (13).

14) Shoe as claimed in claim 13 characterised in that the two U-shaped elements (13, 12) and the recessed seat (15) are so shaped and sized that when the sole is not stressed, they superiorly form a substantially planar bearing surface for the second non compressible layer.

15) Shoe as claimed in claim 13 characterised in that the second damping element (12) has lateral windows (12 A) able to enable to see and touch at least partially the first damping element (10 B) with greater compressibility.

16) Shoe as claimed in claim 13 characterised in that the first U-shaped damping element (13) has additional arms (13 A) extending from the arms of the U and able to house in corresponding additional recessed seats (12 A) provided in the second damping element (12), said arms and additional seats being shaped and sized in such a way that the ends of said additional arms of the first damping element reach the outer face which remains in view of the sole.

17) Shoe as claimed in claim 1 characterised in that the parts of the sole able to support the forefoot (4 B) and the heel (4 A) are two distinct, mutually separate parts and that said two parts are mutually connected by an extension (6) of the substantially non compressible layer (14) of the damping element of the heel, said extension thus serving as a support for the part of the plantar arch of the foot.

18) Shoe as claimed in claim 1 characterised in that the parts (4 A, B) of the sole able to support the forefoot and the heel are two distinct, mutually separate parts and that said two parts are mutually connected by lateral projections (7) extending from the part (4B) of the sole for the forefoot and able to bear on the upper edge of the extension of the substantially non compressible layer (10 A) of the damping element (10) for the heel.

19) Shoe as claimed in claim 1 characterised in that at least one portion of the compressible layers (1OB, 11 C) has at least one recess or a through opening (21, 31) able to increase its compressibility.

20) Shoe as claimed in claim 19 characterised in that the at least one recess or opening (31) is provided in the third layer (11 C)₅ having lower compressibility, of the forefoot part of the sole, at its portion proximate to the start of the part of the plantar arch. 21) Shoe as claimed in claim 19 characterised in that the at least one recess or opening (21) is provided in the first layer (10B), having greater compressibility, of the part for the heel of the sole.

22) Shoe as claimed in claim 5 characterised in that the non compressible portion (16) for closing the opening of the part of sole for the heel has, along its lower surface, a bulge (16 A) able to provide said portion with a variable cross section, thicker at the centre than at its edges.

23) Shoe as claimed in claim 7 characterised in that the tongue (16) is so shaped and sized that, when the shoe is worn, it is substantially underneath the user's heel bone, so that the weight of the user of the shoe is concentrated in the portion of the intermediate sole provided between the edge of the tongue and the surface of the U-shaped element (13) whereon said edge bears.

24) Shoe as claimed in claim 4 characterised in that the part (6) for the plantar arch is an extension of a component of the intermediate sole and that to said part is not fastened an outer sole. 25) Shoe as claimed in claim 4 characterised in that the part (6) for the plantar arch has a thickness (S3) that is considerably smaller than that of the remaining parts of the sole.

26) Shoe as claimed in claim 25 characterised in that the part (S3) for the plantar arch has a thickness (S3) that measured at a longitudinal section of the sole is less than or equal to half the thickness values of the forefoot and heel parts of the sole, measured at the aforesaid sections and of the portions of said parts that are in contact with the ground when the shoe is not worn, preferably said thickness being about equal to ¹A the smaller thickness between said thickness values of the forefoot and heel parts.

27) Shoe as claimed in claim 1 characterised in that the forefoot part (4 B) of the intermediate sole has a main support body (25) extending throughout the surface of the forefoot, but excluding the plantar arch, in the central part of said main body, said body constituting the layer (11 C) of the damping element having lower compressibility, at the region of the foot between the phalanxes and the plantar arch said body comprises a recessed seat (28) able to house the layer (11 B) with greater compressibility, above which is provided a substantially non compressible layer (11 A).

28) Shoe as claimed in claim 27 characterised in that the seat (28) of the support body and the layers (11 B, A) with greater and no compressibility are so shaped and sized that at rest the lower surface of the non compressible layer is substantially coplanar with the upper surface of the support body.

29) Shoe as claimed in claim 27 characterised in that the forefoot part (4B), to improve the damping of the stresses whereto this part of the foot is subjected, the layer with greater compressibility (11 B) comprises a damping element (26) having, at its upper surface whereon bears the non compressible layer, a deep slit (27B) that provides said damping element with substantially U- or C-shaped cross section.

30) Shoe as claimed in claim 29 characterised in that damping element (26) has two arms (26 C) extending from a base (26D), the end whereof is able to serve as a support for the non compressible layer.

31) Shoe as claimed in claim 29 characterised in that the support element (25) of the layer (11 B) with lower compressibility has lateral windows able to enable to see and touch, at least partially, the damping element (26) of the layer having higher compressibility.

32) Shoe as claimed in claim 31 characterised in that recessed seat of the element with lower compressibility (25) is open laterally and in that the damping element (26) with higher compressibility extends through said lateral openings to the front lateral portions of the sole.

33) Shoe as claimed in claim 29 characterised in that the damping element with higher compressibility (26) has a longitudinal slit (27B) able to delimit a through hole in the forefoot part of the shoe.

34) Shoe as claimed in claim 1 characterised in that the substantially non compressible layer (11 A) of the forefoot part (4B) of the sole comprises a substantially planar support element (27) able to bear only on the layer having higher compressibility (HB) of said part (4B).

35) Shoe as claimed in claim 2 characterised in that the outer sole (24) comprises at least two distinct and mutually separate parts (23, 24 A-C) and that said parts are associated only at the forefoot and heel parts of the intermediate sole.

36) Shoe as claimed in claim 1 characterised in that the outer sole (24) of the forefoot part extends only on part of the lower surface of the intermediate sole, the outer sole being absent, at a plurality of flexion lines (36 A-B) of the foot, in such a way that, in the forefoot region the outer sole is subdivided into a plurality of mutually separate islands (24 A-C), said outer sole being absent also at the inner side of the forefoot sole approximately in the portion between the phalanxes and the plantar arch; in this position the outer sole being replaced by an extension (40) of the intermediate sole that remains flush with the adjacent outer sole.

37) Shoe as claimed in claim 1 characterised in that the layers with higher compressibility (10B₅ HB) are made of a plastic material, preferably EVA or PHYLON, with hardness ranging between 30 and 50 C, in that the layers with lower compressibility (10 C, 11 C), provided below the intermediate ones are made of a plastic material, preferably EVA or PHYLON, with hardness ranging between 55 and 65 C, and in that the layers (10 A, 11 A), provided at least partially above said intermediate layer are made of a substantially non compressible plastic material, preferably TPU and/or PVC with hardness ranging between 46 and 50 D.