DESCRIPTION

TECHNICAL FIELD

The present invention refers to footwear and, preferably but not limitedly, to safety footwear.

STATE OF THE ART

As known, safety footwear means that type of footwear suitable for protecting the foot during work. Normally, safety footwear is divided into three main categories: safety footwear, protective footwear, work footwear. Safety and protective footwear have the peculiarity of presenting a rigid toe cap at the toe capable of resisting, without breaking, the fall of a weight from a certain height.

Another feature that may be required for safety footwear is that relating to anti-puncture. In some workplaces there is a risk of walking on sharp objects that could puncture the shoe, such as nails or other sharp objects. Some shoes are therefore designed to prevent accidents caused by perforation of the sole.

More precisely, it would be necessary to differentiate the anti-puncture, according to which any possibility of perforation would be avoided, from the resistance to perforation which instead provides for the definition of an appropriate threshold value beyond which it is possible for perforation to occur. For the purposes of the present invention, the term "anti-puncture characteristics" means characteristics of contrast to perforation, which include a resistance to perforation or an effective anti-puncture.

Document IT-102004901217104 describes a safety footwear having an antipuncture tread sole. This sole is made of composite material and has an external shape, including heel, foot and sole, having flexibility in the sole area and semi-rigidity in the toe.

Document IT-102008901672941 describes a footwear made with a sole injected directly onto the upper that incorporates a mounting insole that allows transpiration under the sole of the foot.

Document US2020/ 163406 describes a footwear with an upper, a sole and an anti-puncture membrane incorporated in the sole. The membrane incorporated in the sole is formed by a layer connected to a functional layer in two portions.

SUMMARY OF THE INVENTION

The Applicant has observed that the current shoes which have antipuncture characteristics do not satisfactorily combine this anti-puncture property with the need for flexibility and stability of the shoe.

The technical problem faced by the present invention is that of providing a footwear which has anti-puncture properties and which, at the same time, can offer the flexibility and stability necessary for a safe and comfortable walk. Furthermore, according to a particular aspect, the problem is also faced of providing a footwear which has improved cushioning and / or anti-puncture properties with respect to those obtainable with the known technique.

According to a first aspect, the aforementioned problem is solved by a footwear as defined by claim 1 and by its preferential embodiments, defined by dependent claims 2 -14.

According to another aspect, the present invention relates to a protective insert for sole defined by claim 15.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is described in detail below, by way of nonlimiting example, with reference to the attached drawings, in which:

- Figure 1 shows a side view of a footwear such as, in particular, a work footwear, the sole of which incorporates a protective insert;

- Figure 2 shows a rear section of said footwear, further provided with upper and insole;

- Figure 3 is a top perspective view of an embodiment of the protective insert comprising a rear element and a front element;

- Figure 4 is a lower perspective view of said embodiment of the protective insert;

- Figure 5 is a top perspective view of the rear element of said protective insert;

- Figure 6A shows a plan view of the rear element of said protective insert;

- Figure 6B is a vertical section of the rear element of Figure 6A;

- Figure 7 shows, according to an example, the upper of said shoe in a phase of application of the protective insert and before the formation of the sole;

- Figures 8 and 9 refer to assembly steps of the upper of Figure 7 on an articulated support for the purpose of forming the sole by direct injection molding;

- Figure 10 shows a vertical section in correspondence to a central part of the heel and illustrates the effect on puncture of a nail obtainable with the protective insert having, preferably, a section with a W-shaped pattern;

- Figure 12 shows an example of said upper equipped with an anti-cut protective layer;

- Figure 13 schematically represents the protection, flexibility and stability properties of said footwear;

- Figure 14 illustrates the flexibility and stiffness properties of the protective insert in a situation where the footwear is bent;

- Figure 15 refers to a comparison between the action of a nail on a W- shaped insert and one with a planar shape;

- Figure 16A shows a conventional footwear and Figure 16B shows by way of example the footwear of Figure 2 highlighting the different behavior with respect to the conventional footwear towards the penetration of a nail;

- Figure 17 shows, in cross section, three different possible types of inserts with a corrugated cross section;

- Figure 18 shows three different sections of the insert according to planes orthogonal to a longitudinal axis of the insert;

- Figure 19 shows a section of the insert according to a longitudinal plane of the insert.

DETAILED DESCRIPTION

Mentre 1'invenzione e suscettibile di varie modifiche e costruzioni alternative, alcune forme di realizzazione particolari sono mostrate nei disegni e saranno descritte qui di seguito in dettaglio. Nella presente descrizione, element! o component! analoghi o identic! saranno indicati nelle figure con lo stesso simbolo identificativo.

While the invention is susceptible to various modifications and alternative constructions, some particular embodiments are shown in the drawings and will be described below in detail. In the present description, similar or identical elements or components will be indicated in the figures with the same identification symbol.

Figures 1 and 2 show a footwear 100 which is preferably a safety footwear and, in particular, a safety or protective footwear. For example, the footwear 100 is a footwear suitable for use in particularly uneven work environments such as areas with the presence of stones, nails or other irregularities (as can happen, for example, in building sites, mines or quarries).

According to an embodiment, the safety footwear 100 comprises a sole 1, an upper 2, an insole 3 and, advantageously, a toe cap 22. A protective insert 4 is arranged inside the sole 1 (also represented in Figures 3 - 6), according to a particular embodiment. The protective insert 4 includes a rear element 5 and a front element 6, made of different materials so as to present different characteristics of rigidity and flexibility.

The rear element 5 is intended to extend into the rear area of the sole 1. In particular, when the user wears the footwear 100, the rear element 5 faces those parts of the human foot called the rear foot and mid foot. In other words, the rear element 5 is intended to be facing the heel and the plantar arch of the foot.

The front element 6 is intended to extend into the front area of the sole 1. In particular, when the user wears the footwear 100, the front element 6 faces that part of the human foot called the forefoot. In other words, the front element 6 faces an area that goes, approximately, from the transverse arch of the foot to the toe of the foot. It should be noted that the rear element 5 is rigid while the front element 6 is flexible. In particular, the rear element 5 (more rigid than the front 6) has characteristics of resistance to puncture and, preferably, also antitorsion.

The rear element 5 is made of a rigid material comprising plastic material. For example, such a plastic material can be a thermoplastic material or a thermosetting material. The plastic material used can be filled with carbon, glass, Kevlar or even wood fibers. For example, this filler can have a weight percentage comprised between 20% and 50%. According to a specific embodiment, the rear element 5 is made of a polyamide loaded with glass fibers with a weight percentage between 20% and 50% .

The front element 6, flexible, is made by means of a textilelaminate also having characteristics of resistance to puncture. As is known, the textile laminate is composed of two or more layers coupled together of fabrics made with fibers in polyester, in aramid material or a combination of these. The front element 6 can be obtained by shearing a multilayer fabric with properties of resistance to puncture.

According to a particular embodiment, the rear element 5 has a first portion 7 configured in such a way as to define a concavity 8 (Figure 3) which is intended, when the protective insert 4 is arranged in the sole 1, to face towards an external surface 12 (Figure 1) of the sole itself. The concavity 8 is substantially located in correspondence with the heel of the foot wearing the footwear 100 and, in particular, extends in correspondence with the rearfoot region.

In correspondence to the concavity 8, the first portion 7 defines a cavity 9 (Figures 3 and 5), intended to be turned towards the insole 3. The cavity 9 has a bottom wall 10 and a side wall 11 (which laterally delimits part of the bottom wall 10).

Considering the footwear 100, the bottom wall 10 of the cavity 9 is spaced from the upper 2 while the side wall 11 extends from the bottom wall 10 approaching the upper 2 and the insole 3, in correspondence with its external edges, while remaining therefrom spaced apart.

This spacing of the bottom wall 10 of the rear element 5 from the insole 3 and therefore, when the footwear 100 is worn by the user's foot, provides greater safety with respect to the puncture of nails compared to prior art solutions which provide anti-puncture elements next to the upper and the insole. In fact, the spacing allows the blocking of a nail before its tip approaches the foot. Figure 16 clarifies this aspect by showing a known type of footwear (Figure 16A) with a flat insert 33 and the footwear 100 (Figure 16B) in which the concavity 8 of the protective insert 4 is more distant from the user's foot than in the case for Figure 16A (where no cavity is present), making it more difficult for a nail 24 to reach the user's foot.

Preferably, returning to Figure 3, the side wall 11 is equipped, in correspondence to an upper edge 18, with a plurality of spacer elements 19 which play an advantageous role in the footwear 100 manufacturing process. Spacer elements 19 allow the first portion 7 to be spaced from the insole 3 by at least 3 mm, preferably a distance of 3.00 mm to 7.00 mm. The bottom wall 10 provides protection against actions (for example, a perforating action of a nail) coming from the bottom of the footwear 100; the side wall 11 also provides protection from objects acting against the rear side portions of the footwear 100.

It should be noted that the rear element 5, being made of rigid material, also gives stability, with anti-torsion effects, to the footwear 100 even in the presence of rough or uneven grounds.

The rear element 5 also has a second portion 13 (Figure 4) (in one piece with the first portion 7) having an essentially planar shape. When the user wears footwear 100, the second portion 13 appears to face the midfoot area or, in other words, is located below the arch of the foot.

As can be seen from Figures 3-6, the protective insert 4 has a shape that substantially reproduces that of the insole of the upper 2.

The rear element 5 is fixed to the front element 6, for example, by gluing. In particular, the second portion 13 has an edge 14 (Figures 5 and 6) configured to be fixed to a further edge 15 of the front element 6.

According to the example of the Figures, the edge 14 is shaped so as to define an abutment wall 16 for the further edge 15 of the front element 6 and a support wall 17 configured to extend, for a short distance (for example, between 10.00 and 20.00 mm), below the front element 6.

In particular, the insert 4 is joined to the upper 2 when this has been completed, also with the application of the insole 3. For example, the insert 4 is joined to the upper 2 by gluing (but could also not be glued) of the outer edge 18 which surrounds the front element 6 with the lower edge of the upper 2.

According to another example, all or part of the upper surface of the front element 6 is glued to the insole 3 and to the edges of the upper 2. In particular, only a part of the toe of the upper surface of the front element 6 is glued to the insole 3 and to the upper 2.

Figures 7 , 8 and 9 refer to a particular embodiment and to some processing steps that precede the application of the sole 1. In particular, as shown in Figure 7, the insert 4 is associated with the upper 2 in the correct position also by means of one or more elastic bands 20 which extend from one side to the other (with respect to a longitudinal axis of the footwear) of the upper itself, for example, in the rear foot area.

The upper 2, already associated with the insert 4, is then fitted on a shoe cast mounted on a support with joint 21 (Figure 8). When assembling on this shoe cast, a flexion of the upper 2 is required. This flexion is allowed by the fact that the rear element 5 is not glued to the upper 2 and therefore can slide on this, as shown in Figure 8. When the upper 2 is fitted on the shoe cast, the upper itself resumes the non-flexed position, as shown in Figure 9.

Effettuato il posizionamento sulla forma, si procede con la costruzione della suola 1 utilizzando, esemplificativamente, una tecnica di stampaggio per iniezione diretta sulla tomaia 2. Secondo particolari forme di attuazione e possibile realizzare suole monodensita o multidensita con battistrada in gomma o in altri polimeri.

Once the positioning on the shoe cast has been carried out, you proceeds with the construction of the sole 1 using, by way of example, a molding technique for direct injection on the upper 2. According to particular embodiments it is possible to produce single-density or multi-density soles with rubber or other polymers treads.

For example, the sole 1 can be obtained by carrying out an injection of liquid polyurethane in a closed mold applied to the upper 2, mounted on the support 21. In particular, the polyurethane is injected from the heel. It should be noted that the protective insert 4 is entirely incorporated in the sole 1 since the injected material can easily slide both laterally and on the front and, advantageously, fill the cavity 9. The filling of the cavity 9 is also facilitated by the spacing with respect to the upper 2 and to the insole 3, ensured by the spacer elements 19. The complete and correct filling of the mold allows the footwear 100 to have suitable absorption and dissipation values of energy, necessary for comfort. In particular (Figure 2), the injected material forms, inside the cavity 9, a first cushioning portion (amortization) 31 and, outside the cavity 9 below the first cushioning portion 31, a second cushioning portion 32 : these cushioning portions 31 and 32 contribute to the comfort of the user of the footwear 100.

It should be noted that the insert 4 can also be used in footwear in which the sole is not obtained by direct injection but is applied with other methods, for example, gluing. Also in this case the sole is constructed so that it incorporates the insert.

With regard to some construction parameters, it should be noted that the insert 4 has a thickness, constant or variable, which can be chosen between 10% and 30% of the total thickness of the sole 1 in the central area of the heel. Preferably, the thickness of the insert 4 can be between 10% and 25% or, more preferably, between 10% and 15% of the total thickness of the sole 1 in the central area of the heel. These values allow to use the protective insert 4 without significantly varying the flexibility and stability characteristics of the sole 1. In merito al posizionamento dell'elemento posteriore 5 nella zona del tacco della suola 1, la posizione e scelta in modo da non ridurre eccessivamente la quantita di poliuretano (o di altro materiale impiegato) al di sotto dell'inserto stesso. Secondo una configurazione preferita 1'inserto 4 e posizionato ad un'altezza, valutata rispetto al sottopiede 3, compresa tra il 35% e il 67% dello spessore totale della suola 1, in corrispondenza del tacco. Preferibilmente, tale altezza e scelta fra il 35% e il 50% dello spessore totale della suola 1 in corrispondenza del tacco.

With regard to the positioning of the rear element 5 in the heel area of the sole 1, the position is chosen so as not to excessively reduce the amount of polyurethane (or other material used) under the insert itself. According to a preferred embodiment, the insert 4 is positioned at a height, evaluated with respect to the insole 3, between 35% and 67% of the total thickness of the sole 1, in correspondence to the heel. Preferably, this height is chosen between 35% and 50% of the total thickness of the sole 1 in correspondence to the heel.

According to a particular embodiment (better visible in Figure 6B) the rear element 5 has a cross section (ie, obtained from a plane perpendicular to a longitudinal axis of the insert 4) which has a wavy, i.e non-planar, course; in other words, a W-type pattern. The undulation may be due, according to an example, to beveled ribs 23 formed on the surface of the concavity 8 (Figure 4), which also play a role in stiffening the shape.

The W shape is particularly advantageous, since in the event of perforation by a nail 24 from below, the surface of the insert 4 against which the nail will impact will be oblique and not orthogonal: this hinders the puncture, because the nail 24 will tend to slide on the surface. In fact, as shown in Figure 10B) the nail 24 is deflected and tends to deform and bend.

Furthermore, it should be noted that a geometry of this type (wavy / ribs) causes the nail 24 to almost always have to cross a surface with a greater thickness than that to be crossed if the insert 4 were completely planar. Figure 15 shows by way of example a comparison between a thickness dl (Figure 15 A) that the nail 24 should pass through in the case of a W pattern and a thickness d2 (lower than dl) that the nail 24 should pass through in the case of a planar pattern. In this regard, the Applicant has experimentally verified that a 0.1 mm thickness increase of the first portion 7 of the insert 4 produces an increase in puncture resistance varying between 5% and 10% .

Figure 17 shows further variants of the insert 4 with reference to the wavy shape of the cross section. In particular, Figure 17 refers to the first portion 7 of the rear element 5 of the insert 4.

It should be noted that in Figure 17A the insert 4 has a wavy cross section having a single crest CI inside the cavity 9 and two crests CE outside the cavity 9 (i.e. facing the external surface 12, indicated in Figure 1). The term "crest" means the highest point (upper crest or inner crest CI) or lowest (lower crest or outer crest CE) of the wave identified by the section shown.

In Figure 17B the insert 4 has a wavy cross section having two crests CI inside the cavity 9 and three crests CE outside the cavity 9, similarly to the examples of Figures 2 and 10.

In figure 17C the insert 4 has a wavy cross section having three crests CI inside the cavity 9 and four crests CE outside the cavity 9. Figure 18 shows by way of example three different types of corrugation with reference to three different transversal sections according to planes which intersect the rear portion 5 in different positions along a longitudinal axis.

As shown by way of example in Figure 18, it should be noted that the undulation is more marked in the area of the first portion 7 intended to face the heel and progressively decreases as one moves away from the heel and approaches the second portion 13 (intended to face the midfoot). In other words, the width of the crests (external CE or internal CI) of the cross sections of the posterior portion 7 is greater near the heel and decreases approaching the second portion 13. Furthermore, each external ridge CE defines longitudinally a relative rib 23 in the longitudinal direction.

The waving can be sinusoidal, not perfectly sinusoidal or even non- sinusoidal.

It should be noted (Figure 17) that each internal crest CI is opposed to a relative external trough VE and each external crest CE is opposed to a relative internal trough VI. Each external (or internal) crest is separated from the internal (or external) trough to which it faces by a distance equal to the thickness of the insert 4 in that section.

For example, the waving can be such that, in the longitudinal section in which this waving is more pronounced, the distance between a horizontal plane associated with the bottom wall 10 (for example, the plane tangent to the external crests CE) and a trough external VE is between 0.500 mm and 5.00 mm, preferably between 1.00 mm and 4.00 mm and even more preferably between 2.5 mm and 3.5 mm. Furthermore, according to an example that agrees with the values indicated above, the distance (evaluated along the horizontal plane defined above) between an external crest CE and a consecutive external trough VE can be between 6.00 mm and 14.00 mm, preferably between 8.00 mm and 12.00 mm or, more preferably, between 9.5 mm and 10.5 mm.

Another constructive aspect is that relating to the slope of the side wall 11 which helps to define the cavity 9. It should be noted that, advantageously, the side wall 11 is joined to the bottom wall 10 so as to form a curved or noncurved connecting wall, for example, at right angles. As described with reference to Figure 15, this slope plays an advantageous role in deflecting the nail 24.

Figure 18 relating to section A-A shows, by way of example, some slope values expressed as angular values. Each angle is defined as comprised between the horizontal plane (defined above) and the straight-line tangent to the side wall 11 at a point on the wall itself. Each point is identified by the distance (in mm) between the most lateral external crest CE, and the point of intersection between the perpendicular to the horizontal plane passing through the point of tangency considered. According to the example, in Figure 18 the following angular values are indicated: 32.1° for a point at 4.00 mm of distance; 55.9° for a point at 8.00 mm of distance; 69.00° for a point at 10.00 mm of distance; 78° for a point at 12.00 mm of distance. Figure 19 refers to a longitudinal section of the rear portion 5 of the insert 4 and shows some exemplary angular values measured with respect to the aforementioned horizontal plane. Each angle is defined between the horizontal plane and the straight-line tangent to the side wall 11 at a point on the wall itself. Also in this case, each tangent point is identified by the distance (in mm) between the lowest point of the side wall 11 (which connects to the bottom wall 10) and the point of intersection between the perpendicular to the horizontal plane passing through the point of tangency considered.

According to the example, in Figure 19 the following angular values of the slopes are indicated: 16.3 ° for a point at 5.00 mm distance; 29.6 ° for a point at 10.00 mm distance; 43.20 ° for a point 15.00 mm distance; 57.6 ° for a point 17.50 mm distance and 74.7 ° for a point 20.00mm distance.

In particular, the slope (defined above) of the side wall 11 (both with reference to Figure 18 and to Figure 19) varies, increasing, between a minimum value found in correspondence with the connection with the bottom wall 10 and a maximum value found in correspondence with the free edge of the side wall itself.

It should be noted that according to some embodiments, the slope of the side wall 11 (both with reference to Figure 18 and to Figure 19) varies, moving away from the connection with the bottom wall 10) between a value of about 15 ° and a value of about 85 °, preferably, this slope varies between a value of about 20 ° and a value of about 80 °.

The Applicant has made a footwear 100 of the type described here and has evaluated its performance. Footwear 100 has been tested according to the following current legislation: EN ISO 20345: 2011 "Personal protective equipment - safety footwear" and EN ISO 20344: 2011 "Personal protective equipment - Test methods". In particular, using a 4.5 mm diameter conical nail, an average puncture resistance of 2,000 N (Newton) was obtained, with peaks exceeding 2,500 N. It should be noted that the regulatory requirement is 1,100 N and therefore the result obtained is about 80% more than that required by the standard.

Furthermore, the Applicant has tested the footwear 100 using a conical nail having a diameter of 3mm (that is, in a more severe condition than that of the standard). With this test, an average resistance to puncture of 1.600 N was measured (45% more than the value required by the standard), with peaks of 2.000,00 N.

These results are extremely satisfactory and it is possible to state that the use of the insert 4 allows to obtain a footwear 100 which not only has a considerable resistance to puncture but which almost achieves an ideal antipuncture performance.

It should be noted that the second portion 13 has been defined as "substantially planar" meaning that it has a reduced or negligible undulation but it can be slightly concave to couple adequately to the front element 6. In particular, the edge 14 (Figures 5 and 6) of the second portion 13, configured to be fixed to a further edge 15 of the front element 6, has no undulations.

Figure 11 refers to a particular embodiment in which the insert 4 is equipped with two recesses 25 formed on facing edges of the rear element 5 to house the elastic band 20 in a correct position.

It should be noted that according to a particularly advantageous embodiment, the footwear 100 has further protection characteristics. Figure 12 shows an internal view of the upper 2, in a step that precedes the sewing of the insole 3 and according to a particular embodiment. The upper 2 is associated with a protective layer 27, in anti-cut material, interposed between a side lining 26 and the upper itself. Furthermore, Figure 12 shows a front liner 28.

In addition, the upper 2 can be equipped with a rear reinforcement 29 that wraps the heel area and two lateral reinforcements 30 (Figure 1) such as to at least partially surround the user's ankle and instep. These reinforcements 29 and 30 can be made, for example, of thermoplastic material (for example, polyurethane), thermosetting material or rubber and, together with the insert 4, help to give stability to the foot. According to a particular embodiment, the lateral reinforcements 30 can be made of synthetic materials or leather.

Further protection is provided by the toe cap 22 which has characteristics of resistance to puncture and can protect against impacts and compressions. Said toe cap 22 can be, for example, made of metal, plastic or composite material.

The footwear 100 as described above has particularly advantageous characteristics: protection, stability and flexibility, as symbolically indicated in Figure 13.

The protection provided by the sole 1 (ensured by the protective insert 4) is advantageously increased by other elements associated with the upper 2 such as: the protective layer 27 in anti-cut material, the rear reinforcement 29, the lateral reinforcements 30 and the toe cap 22 ( highlighted in Figure 13, as P). The stability conferred by the rigid insert 4, which supports the heel and ankle, is increased by the rear reinforcement 29 and by the lateral reinforcements 30, which partially embrace the ankle (area S in Figure 13).

The flexibility of the footwear 100 is ensured by the insert 4 having has the front element 6 which ensures a flexibility that does not contrast with the natural one of the foot (area F, in Figure 13). Figure 14 shows how the footwear 100 can bend when the user, for example, is kneeling to perform a certain activity. The footwear 100 ensures the correct functionality of the joints, in particular of the metatarsal ones.

It should be noted that an extremely rigid sole would reduce the sensitivity in the perception of the ground, therefore, it can cause injuries. Instead, the protective insert 4 allows the sole 1 to be stiffened to the extent necessary to give stability but maintaining the right sensitivity for the user. This quality, especially in the case of rough and uneven ground, allows for greater safety, as it allows the user to perceive the ground, without feeling the roughness, and maintaining control of the walk.

Furthermore, as illustrated above, the spacing of the bottom wall 10 of the rear element 5 from the insole 3 and therefore, when the footwear 100 is worn, by the user's foot, provides a particular safety with respect to the puncture of nails.

It should be noted that, advantageously, the insert 4 can be manufactured in such a way as to comply with the requirements set by the standard on components EN ISO 12568: 2010 and EN ISO 22568-4: 2020 "Requirements and test methods for footwear components" (both for a 4.5 mm truncated conical nail than for the 3 mm truncated conical nail).

Furthermore, footwear 100 equipped with insert 4 can also be manufactured to meet the requirements of EN ISO 20345: 2011 "Personal protective equipment - safety footwear" and EN ISO 20344: 2011 "Personal protective equipment - Test methods ".

KEY TO COMPONENTS OF THE FIGURES

- footwear 100

- sole 1

- upper 2

- insole 3

- protective insert 4

- rear element 5

- front element 6

- first portion 7

- concavity 8

- cavity 9

- bottom wall 10

- side wall 11

- external surface 12

- second portion 13

- edge 14

- additional edge 15

- stop wall 16

- support wall 17 - upper edge 18

- spacer elements 19

- elastic band 20

- support 21 - toe cup 22

- ribs 23

- nail 24

- recess 25

- side lining 26 - protective layer 27

- front lining 28

- rear reinforcement 29

- side reinforcement 30

- first cushioning portion 31 - second cushioning portion 32

- conventional insert 33