SHOE SOLE.

Description

DESCRIPTION in support of a patent application for an industrial invention entitled: “SHOE SOLE”. Owner: “SANTONI SOCIETA' PER AZIONI”, with registered office in MILAN (MI), Via Monte Napoleone 9 DEPOSITED ON............. DESCRIPTION TEXT The present invention relates to a sole for footwear. In the footwear sector, soles in ethyl vinyl acetate (EVA), as EVA ensures good compromise between mechanical resistance, comfort and lightness of the sole. Subsequently, when we talk about shore A, we mean an indication of the hardness of the sole, measured according to the ISO 868 standard with the ball tool in one time minimum of 15 seconds. Generally, EVA soles, according to the known technique, use medium density EVA. Therefore these soles have hardness of about 50 shore A. This value of hardness of the sole It has been studied and selected specifically to have good compromise between mechanical resistance, comfort and lightness of the sole. The footwear market requires increasingly thicker soles light, soft and comfortable. However, if EVA is used to make a sole low density, so as to obtain a sole having a density less than 0.4 g / cm and a hardness less than 40 shore A, such soles have some drawbacks. In fact, particularly soft soles tend to form wrinkles, especially in the heel area which is the area of greater thickness of the sole and also the area subject to greater stress or load during walking. In fact while walking, the contact of the shoe with the ground It happens first of all with the heel of the sole on which the heel of the foot. Then the outer arch of the foot goes in support on an external lateral part of the sole. So the pressure is greater right on the heel of the sole where it they form wrinkles. These wrinkles are plastic wrinkles, in the sense that, a once formed, they remain permanently, not being subject to natural elastic rebound. Fig. 1 illustrates a sole (100) made of EVA low density and having a hardness of 30 shore A. The sole (100) it has a heel (102) which constitutes the thickest part of the sole. Following compression tests simulating the weight of an average user and a walk, in the heel area (102) yes a plurality of wrinkles (G) are formed. As shown in Fig. 1, these wrinkles (G) are clearly visible to the naked eye and therefore affect the aesthetic appearance of the footwear that will adopt that type of sole. The purpose of this invention is to eliminate the drawbacks of the prior art, providing a sole for footwear that is particularly soft, light and give it to you and that at the same time it is not subject to wrinkles. These objects are achieved in accordance with the invention with the characteristics of the annexed independent claims. Advantageous embodiments of the invention appear from dependent claims. Further features of the invention will appear later. clear from the detailed description that follows, referring to one of his purely exemplary embodiment and therefore not limiting, illustrated in the attached drawings, in which: Fig. 1 is a perspective view of a sole according to the known technique having wrinkles in the heel; Fig. 2 is a perspective view of a sole according to the invention; Fig. 3 is a perspective view from the rear of the sole of Fig. 2; Fig. 4 is a front perspective view of the sole of Fig. 2; Fig. 5 is a bottom plan view of the sole of Fig. 2; and Fig. 6 is a photograph illustrating a portion of the heel of a sole according to the invention; Fig. 7 is a front view of a portion of the boss of the heel of the sole according to the invention; and Fig. 8 is a sectional view taken along the plane of horizontal section VIII-VIII of Fig. 7. With the help of Figures 2 to 8 a description is given of sole according to the invention, indicated as a whole with the reference number 1. The sole (1) is made of low density EVA for molding in a shoe sole mold within which the EVA polymer cross-links. The sole (1) obtained has a density lower than 0.4 g / cm, preferably between 0.28 – 0.38 g / cm , more preferably 0.33 g / cm and a hardness less than 40 shore A, preferably between 25 – 35 shore A, plus preferably equal to 30 shore A. The sole (1) has a heel (2), a central part (3) in correspondence of the plantar arch and a front part (4). The heel (2) is the thickest part of the sole. The front part (4) of the sole has a thickness (S4). With reference to Figs. 2 and 5, the central part (3) of the sole has a variable thickness with a minimum thickness (S3) in the internal plantar arch areas (31) and the plantar arch external (32). This minimum thickness (S1) is gradually growing towards a median zone (33) of the part central and towards the front (4) of the sole where the thickness of the central part (3) connects with the thickness (S4) of the front part (4) of the sole. The heel (2) has a thickness (S2) greater than double of the thickness (S3) of the front part of the sole. In fact the heel (2) forms a step with respect to the central part (3) of the sole. Generally the ratio between the thickness (S2) of the heel and the thickness (S4) of the front part of the sole is between 2.5-4. The sole (1) has an upper edge (5) that protrudes towards the high surrounding the sole perimeter, so as to define a recessed seat (6) intended to accommodate a midsole. The upper edge (5) also serves for assembly of the upper on the sole. In the heel area (2) there are openings of lightening (7) open at the top. Each opening of lightening (7), seen in plan, has a quadrilateral shape with a strip of material (70) arranged according to a diagonal of the quadrilateral. The strip of material (70) acts from stiffening rib to avoid excessive deformation of the heel (2) of the sole at the lightening openings (7). In the front part (4) of the sole there can be at least a lightening slot (8) in the shape of a buttonhole which extends transversely. The heel (2) has an external lateral surface (20) shaped of “U”. According to the invention, on the external lateral surface (20) there is a bossage (9) on the heel. The bossage (9) comprises a plurality of protrusions (90) that protrude towards the outside of the external lateral surface (20) of the heel. Advantageously each protrusion (90) has a shape pyramid-shaped with the base of the pyramid on the lateral surface external (20) of the heel. Preferably each protrusion (90) It has a pyramid shape with a square or rhomboid base, in so that the embossing (9) forms a texture of the type diamond. With reference to Figs. 7 and 8, each protrusion (90) has a height (H) of 0.5-1 mm and a diagonal (D) of the base of 1-2 mm. The protrusions (90) are aligned in rows along a diagonal of the base with a pitch (P) of 1-2 mm. The rows of protrusions (90) are alternately staggered with respect to each other. With reference to Fig. 3, the boss (9) is made in a median part with respect to the height of the lateral surface (20) of the heel, i.e., the lateral surface (20) of the heel has a lower stripe (21) with no protrusions below the bossatura (9) and an upper strip (22) without protrusions above above the bossage (9). The lower strip (21) of the lateral surface of the heel is smooth. The upper strip (22) of the surface The side of the heel has no protrusions similar to those of the rustication, but has a rough and dotted surface that creates a sand effect. In this way, the embossing (9) of the lateral surface the outside of the heel is interrupted a short distance from an edge bottom of the heel, leaving a perimeter band made up of from the lower strip (21) smooth without protrusions, of height constant, imitating a typical under-heel. With reference to Fig. 2, the boss (9) extends for a height (H9) on the external lateral surface (20) of the heel. The ratio between the height (H9) of the extension of the bossage and the thickness (S) of the heel is equal to 0.4 – 0.8. The embossing (9) provided on the edge (20) of the heel prevents the formation of wrinkles in the heel. Several tests carried out with the sole (1), simulating the weight of a person and walking, they showed that no wrinkles are generated in the heel (2), precisely thanks to the bossatura (9). The front part (4) of the sole has a lateral edge external (40) in the shape of a “U”. Advantageously, the sole (1) may include a second bossage (109) made on the external side edge (40) of the front part of the sole. second bossing (109) of the front part of the sole has a structure equal to the embossing (9) of the heel. Therefore also the second bossage (109) includes raised parts (90) equal to those of the embossing (9) of the heel. The second bossage (9) extends only in one part front of the outer side edge (40) of the front part of the sole. With reference to Fig. 5, the central part (3) of the sole has a first lateral edge (30a) which extends in correspondence of the external plantar arch (31) and a second lateral edge (30b) extending at the arch internal plantar (32). The first lateral edge (30a) and the second side edge (30b) of the central part of the sole do not have any protrusions similar to the protrusions of the bossatura, but they have a rough and dotted surface that creates an effect sand. In fact the central part (3) of the sole is the part of the sole subject to less pressure during walking. Therefore, in this case, the rough surface of the first and second lateral edge (30a, 30b) of the central part is enough to avoid wrinkles in the central part. In the present embodiment of the invention, equivalent changes and modifications may be made, within the reach of a technician in the field, which however fall within within the scope of the invention expressed by the claims annexes. THE AGENCY ING. CLAUDIO BALDI SRL (ENG. GIANLUIGI CUTROPIA)

Claims

1. Sole (1) made of low density Ethyl-Vinyl-Acetate (EVA), by moulding, so that said sole (1) has a density lower than 0.4 g / cm3 and a hardness lower than 40 shore A, wherein said sole (1) comprises a heel (2), a central part (3) corresponding to a plantar arch and a front part (4) and said heel (2) has an external lateral surface (20) and a boss (9) made in said external lateral surface (20) of the heel; said boss (9) having protrusions (90) which protrude from said external lateral surface (20) of the heel.

2. Sole (1) according to claim 1, wherein the heel (2) is the thickest part of the sole.

3. Sole (1) according to claim 1 or 2, wherein each protrusion (90) of the boss has a pyramid shape with a base of the pyramid on the outer lateral surface (20) of the heel.

4. Sole (1) according to claim 3, wherein each protrusion (90) of the boss has a pyramid shape with a square or rhomboid base.

5. Sole (1) according to claim 4, wherein each protrusion (90) of the boss has a height (H) of 0.5-1 mm and a diagonal (D) of the base of 1-2 mm.

6. Sole (1) according to any of claims 3 to 5, wherein the protrusions (90) of the bossing are aligned in horizontal rows along a diagonal of the base and the rows of protrusions (90) are alternately staggered with respect to each other.

7. Sole (1) according to claim 6, wherein the protrusions (90) of a row are arranged with a pitch (P) of 1-2 mm.

8. Sole (1) according to any of claims 3 to 7, wherein the boss (9) is made in a median part with respect to the height of the external lateral surface (20) of the heel, so that the external lateral surface (20) of the heel has a lower strip (21) without protrusions, below the boss (9) and an upper strip (22) without protrusions, above the boss (9).

9. Sole (1) according to claim 8, wherein the lower strip (21) and the upper strip (22) of the external lateral surface of the heel do not have protrusions similar to those of the bossing (9), the lower strip (21) is smooth and the upper strip (22) is rough and dotted.

10. Sole (1) according to any of the preceding claims, wherein the front part (4) of the sole has an outer lateral edge (40) and a second boss (109) made on the outer lateral edge (40) of the front part of the sole; said second boss (109) having projections (90) protruding from said outer lateral edge (40) of the front part of the sole.

11. Sole (1) according to any of the preceding claims, wherein the central part (3) of the sole has a first lateral edge (30a) which extends in correspondence with an external plantar arch (31) and a second lateral edge (30b) which extends in correspondence with an internal plantar arch (32); wherein the first lateral edge (30a) and the second lateral edge (30b) of the central part of the sole have a rough and dotted surface.