Patent Publication Number: US-11019877-B2

Title: Sport footwear for practicing winter sports

Description:
BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention concerns sport footwear for practicing winter sports, such as for example a ski boot, a snowboard boot or similar sports equipment, in which a substantially closed and impermeable structure, called shell, made of a first material, defines a compartment to receive and position the user&#39;s foot. 
     Description of Related Art 
     Sport footwear for winter sports, such as ski boots, snowboard boots or suchlike are known, which comprise a substantially closed structure at the side and bottom. The structure is commonly known as the shell, and can be made by molding relatively “soft” polymer materials, such as polyethylene or similar polyolefins in general, which are deformable and flexible enough to follow and adapt to the movement of a user&#39;s foot and ankle, supplying the required comfort. 
     Such polyolefin-based materials are generally economical and considered “poorer” materials than others with better mechanical properties, such as polyurethane. 
     The lower parts of the shell, in correspondence with the heel and the toe, commonly comprise flaps or coupling projections, rear and front, suitable to be selectively attached to ski or snowboard bindings. 
     The coupling projections must consequently be suitable to resist wear due to mechanical stresses that occur when the ski or snowboard is used, in particular due to the clamping action of the bindings and, at the same time, to facilitate the sliding/running of the coupling projections inside the bindings. The mechanical coupling of the heel and toe coupling projections and the bindings is so important that specific regulations are dedicated to these zones, to ensure the mechanical grip of the parts, to such an extent that in this technical field, the region of the heel and toe coupling projections is the one subject to the strictest regulations. 
     Sport footwear for practicing winter sports is known, which provides reinforcement elements, stably attached or made on the shell near the heel and toe, made of a material with high properties of mechanical resistance, in particular resistance to wear, such as polyurethane. The reinforcement elements can be made by autonomous molding with respect to the shell, or attached by suitable known attachment means, such as screws or joint mechanisms. The reinforcement elements are associated to the bindings of the ski or snowboard. 
     One disadvantage of these embodiments is that the reinforcement elements and the corresponding attachment means increase the overall weight of the sport footwear, which can entail a disadvantage for the user in terms of possible poorer performance and loss of balance, or because a greater weight of the footwear can impede movement. 
     Another disadvantage of these embodiments is that the reinforcement elements can lead to raising the barycenter of the combined sport footwear/ski or snowboard, leading to a reduction in stability for the user. 
     Boots are also known in which the polyethylene shell and the polyurethane reinforcement elements are made in a single body by a hot co-molding process. 
     One disadvantage of such boots is that polyurethane and polyethylene are incompatible materials in terms of chemical-physical properties, for example they have different coefficients of heat dilation, and consequently can deform in a non-uniform and unpredictable manner, bringing the risk of the boot becoming detached from the movement member. 
     Another disadvantage of these embodiments is that molding the reinforcement elements can lead to burrs or to the formation of discard material. In particular, burrs and the formation of discard materials that are very precious and expensive, like polyurethane, lead to economic losses for the production companies. 
     Furthermore, there is a need to reduce the production costs of the sport footwear in question, while maintaining good mechanical properties, comfort and performance. In particular, there is a need to reduce to a minimum the use of “precious” materials, such as polyurethane, exploiting to the utmost more economical materials, such as polyolefins. 
     U.S. Pat. No. 4,351,120 describes a ski boot provided with traction components that have traction surfaces with various characteristics, depending on the type of use, which can be mounted interchangeably using snap-in clamping elements. These interchangeable components develop mainly in the lower part of the ski boot which rests on the ground during use and, since they are provided to define traction surfaces, they must be made of materials suitable for this purpose; however, these are not suitable in terms of rigidity and resistance to support the mechanical stresses and wear due to the action of the bindings clamping the sport equipment. U.S. Pat. No. 5,615,498, DE-A-2449514 and US-A-2002/000052 describe other ski boots of a known type. 
     There therefore exists a need to perfect sport footwear for practicing winter sports that can overcome at least one of the shortcomings of the state of the art. 
     In particular, one purpose of the present invention is to obtain sport footwear for practicing winter sports, such as ski boots, snowboard boots or suchlike, which fully satisfies the requirements of mechanical grip and sliding of the region of the heel and toe coupling projections but which at the same time can be produced at lower cost, in particular in terms of raw plastic materials. In particular, there is a strongly felt need to make the shell in a light plastic material but which, in the zones of contact with the bindings or coupling projections, has properties of high mechanical resistance, in particular resistance to wear, more particularly to the wear deriving from the stresses of the bindings clamping the sports equipment, and which at the same time facilitates the sliding inside the bindings. 
     Another purpose of the present invention is to obtain sport footwear with a lower weight and which allows to keep a low barycenter of the combined sport footwear/ski or snowboard. 
     The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is set forth and characterized in the independent claims, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea. 
     In accordance with the above purposes, the present invention concerns sport footwear for practicing winter sports such as for example a ski boot, a snowboard boot or similar sports equipment. 
     The sport footwear comprises a shell to receive the user&#39;s foot. The shell is made of a first thermoplastic material, and comprises a front toe portion and a back heel portion. The shell is closed at the lower part by a sole. The shell also comprises at the front a toe coupling projection and at the back a heel coupling projection, configured to couple releasably to the bindings of a ski or snowboard. 
     The sport footwear comprises at least a coupling projection protection cover or cap, releasably attached on at least one or on both of said toe coupling projection and heel coupling projection, said at least one coupling projection protection cover being made of a second thermoplastic material different from and with greater mechanical resistance than said first thermoplastic material. 
     The present invention allows to make the shell in the first thermoplastic material, which is “soft” and economical, since it is chosen for this purpose and has properties of flexibility or deformability as well as lightness, thus facilitating the movements of the user&#39;s foot. The invention also allows to make the coupling projection protection cover in the second thermoplastic material, more precious in mechanical terms, in particular more resistant to wear, at the same time allowing an adequate sliding with respect to the bindings. In this way the invention allows to use as little of the second thermoplastic material as possible, without negatively affecting—and indeed, fully satisfying—the requirements typically laid down for the region of the heel and toe coupling projections. 
     In particular, the coupling projection protection covers are typically made autonomously from the shell, for example by molding, thus reducing possible disadvantages deriving from co-molding with the shell. 
     In some forms of embodiment, the sport footwear comprises at least a heel contact plate releasably attached to the lower part of the sole in the heel portion and/or a toe contact plate releasably attached to the lower part of the sole in the toe portion. The at least one coupling projection protection cover is releasably connected between a respective heel contact plate and/or toe contact plate and a lower part of the sole in the respective toe portion and/or heel portion. 
     In some forms of embodiment, the front toe portion and the rear heel portion are integral and in a single piece with the shell, including respectively the toe coupling projection and the heel coupling projection. 
     In some forms of embodiment, the first thermoplastic material is chosen from a group comprising a polyolefin, a blend of polyethylene with other polymers or additives, a toughened polyethylene or another polymer material containing at least one type of polyethylene. 
     Generally these materials have an optimal compromise between elasticity, softness, appearance and economy of transforming the materials. 
     In particular, toughened polyethylenes can have properties of greater resistance, especially at low temperatures, and an appropriate elastic modulus. 
     In some forms of embodiment, the second material can be chosen between a polyurethane-based material or a polyamide-based material. These materials are particularly resistant to wear and at the same time allow the coupling projections to slide inside the bindings. 
     In some forms of embodiment the thickness of the cover can be comprised between 0.5 mm and 5 mm, more preferably between 1 mm and 3 mm. 
     The reduced thickness of the covers allows to reduce the overall weight of the sport footwear and at the same time to reduce the quantity of second material used compared to known forms of embodiment. 
     Using covers with reduced thickness also allows to keep the barycenter of the combined sport footwear/movement member low, even if the cover is even partly positioned between shell and movement member. 
     In one form of embodiment, the at least one coupling projection protection cover is configured to cover exclusively an upper and/or lateral part of one, the other or both said toe coupling projection and heel coupling projection, providing at the lower part only attachment portions to the shell. 
     The present invention also concerns a method to make sport footwear for practicing winter sports, comprising:
         molding a shell to receive a user&#39;s foot, using a first thermoplastic material, making a front toe portion and a back heel portion, a toe coupling projection being provided at the front and a heel coupling projection being provided at the back, configured to couple releasably with the bindings of a ski or snowboard;   making available at least a coupling projection protection cover made of a second thermoplastic material, different from and having greater mechanical resistance than said first thermoplastic material,   the releasable attachment of said at least one coupling projection protection cover on at least one of, or on both of, said toe coupling projection and said heel coupling projection.       

     These and other aspects, characteristics and advantages of the present disclosure will be better understood with reference to the following description, drawings and attached claims. The drawings, which are integrated and form part of the present description, show some forms of embodiment of the present invention, and together with the description, are intended to describe the principles of the disclosure. 
     The various aspects and characteristics described in the present description can be applied individually where possible. These individual aspects, for example aspects and characteristics described in the attached dependent claims, can be the object of divisional applications. 
     It is understood that any aspect or characteristic that is discovered, during the patenting process, to be already known, shall not be claimed and shall be the object of a disclaimer. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       These and other characteristics of the present invention will become apparent from the following description of some forms of embodiment, given as a non-restrictive example with reference to the attached drawings wherein: 
         FIG. 1  is a lateral view of some forms of embodiment of the sport footwear for practicing winter sports according to the present invention; 
         FIG. 2  is a view from below of some forms of embodiment of the sport footwear according to the present invention; 
         FIG. 3  is a section view from III to III in  FIG. 2 ; 
         FIG. 4  is a section view from IV to IV in  FIG. 2 ; 
         FIG. 5  is a perspective view in separate parts of forms of embodiment of the sport footwear according to the present invention; 
         FIG. 6  is a perspective view of a detail of forms of embodiment of the sport footwear according to the present invention; 
         FIG. 7  is a section view of a detail of form of embodiment of the sport footwear according to the present invention. 
     
    
    
     To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one form of embodiment can conveniently be incorporated into other forms of embodiment without further clarifications. 
     DETAILED DESCRIPTION OF THE INVENTION 
     We shall now refer in detail to the various forms of embodiment of the present invention, of which one or more examples are shown in the attached drawings. Each example is supplied by way of illustration of the invention and shall not be understood as a limitation thereof. For example, the characteristics shown or described insomuch as they are part of one form of embodiment can be adopted on, or in association with, other forms of embodiment to produce another form of embodiment. It is understood that the present invention shall include all such modifications and variants. 
       FIG. 1  is used to describe forms of embodiment of sport footwear  10  for practicing winter sports, such as for example a ski boot, a snowboard boot or similar sports equipment. 
     The sport footwear  10  comprises a shell  11  configured to receive a user&#39;s foot. Typically, the shell is made of a first thermoplastic material. 
     In some forms of embodiment, the shell  11  is shaped, for example by a molding step, for example typically by injection, so as to define a compartment  25  ( FIG. 2 ), which has shape and sizes suitable to contain the user&#39;s foot. 
     In some forms of embodiment, the shell  11  can be closed at the lower part by a sole  14 , and at the sides it can be impermeable to water and can have an upper aperture  26 , in correspondence with which closing elements of a known type are suitable to be disposed, not shown in the drawings. 
     The first thermoplastic material can be chosen for example from the group comprising polyolefins, in particular polyethylene, or a blend of polyethylene with other polymers or additives, a toughened polyethylene or another polymer material containing at least one type of polyethylene. 
     In particular, toughened polyethylenes can have properties of greater resistance, especially at low temperatures, and an appropriate elastic modulus. Examples of polyethylene or blends of polyethylene usable for the shell  11  include elastomer compounds containing thermoplastic block copolymers, such as styrenic block copolymers, for example SBS, SEBS, SEPS, such as Megol® (TPE-SEBS) or Marfran® (TPE-SBS) or other type, such as Apigo® (TPE-TPO). These materials have an optimal compromise between elasticity, softness, appearance and economy in transforming the materials. 
     In some forms of embodiment, the shell  11  can comprise a front toe portion  27  and a rear heel portion  28 . 
     In some forms of embodiment, at the front the shell  11  can comprise a toe coupling projection  12 , or front tongue or nose, and at the rear a heel coupling projection  13 , or rear tongue or tail, configured to couple releasably with the bindings of a ski or snowboard, in particular defining members for the connection, for example by clamping, with bindings to the sports equipment. 
     In possible implementations, the front toe portion  27  and the rear heel portion  28  are integral and in a single piece with the shell  11 , including respectively the toe coupling projection  12  and the heel coupling projection  13 . 
     In other forms of embodiment, the shell  11  can comprise a single coupling projection  12 ,  13 , positioned in correspondence with the toe portion  27  or the heel portion  28 , for example in relation to the type of sport or application of the sport footwear  10 . 
     In forms of embodiment described with reference to  FIG. 1 , the sport footwear  10  comprises at least one coupling projection protection cover, or cap, in this case a first coupling projection protection cover  15  and a second coupling projection protection cover  16 , each of which can be configured to be releasably attached on at least one of said coupling projections  12 ,  13 . 
     In some forms of embodiment, the first coupling projection protection cover  15  and the second coupling projection protection cover  16  can be made of a second thermoplastic material, different from and with a greater mechanical resistance than the first thermoplastic material. 
     The second material is such as to be able to resist wear, and has a high mechanical resistance to stresses extending over time and a high level of hardness. 
     Furthermore, the second material is preferably configured to facilitate sliding inside the bindings, having microscopic characteristics such as to reduce friction with the materials that the bindings are made of. 
     In some forms of embodiment, the second material is chosen from a group comprising a polyurethane-based or polyamide-based material. The polyamide-based material can typically be aliphatic or semi-aromatic polyamide, that is, nylon, such as polyamide 6 (PA 6), or polyamide 66 (PA 66), polyamide 610 (PA 610), polyamide 612 (PA 612) or also polyamide 12 (PA 12). 
     In some forms of embodiment, it is possible to use blends or engineered compounds with a polyamide base, such as for example Schulamid® 6, Schulamid® 66, Schulamid® 610, Schulamid® 612 or Schulamid® 12. Another example of a product that can be used is a compound with a polyamide 6 base reinforced with fiberglass, for example 30% in weight of fiberglass, such as Schulamid® 6 GF 30 TC. 
     In some forms of embodiment the sport footwear  10  can comprise a single coupling projection protection cover  15 ,  16 , positioned for example in correspondence with the toe coupling projection  12  or the heel coupling projection  13 , that is, in correspondence respectively with the toe portion  27  or the heel portion  28 . 
     In some forms of embodiment, the sport footwear  10  can also comprise a heel contact plate  30  and a toe contact plate  31 , configured to be positioned during use between the sport footwear  10  and the movement member, and to stabilize the reciprocal adhesion thereof. In particular, the heel contact plate  30  and the toe contact plate  31  can function as interaction components between the sport footwear  10  and the movement member, for example in the case of sports practice, in particular skiing, or between the sport footwear  10  and the ground on which the user proceeds, for example when walking. 
     In some forms of embodiment, the heel contact plate  30  can be attached releasably below the sole  14  in the heel portion  28 . In some forms of embodiment, moreover, the toe contact plate  31  can be attached releasably below the sole  14  in the toe portion  27 . 
     In some forms of embodiment, the at least one coupling projection protection cover  15 ,  16 , or possibly the two coupling projection protection covers  15 ,  16  can be releasably connected between a respective heel contact plate  30  and/or toe contact plate  31  and a lower part of the respective toe portion  27  and/or heel portion  28 . In particular, attachment portions  32  of the coupling projection protection covers  15 ,  16  can be provided, disposed between a respective heel contact plate  30  and toe contact plate  31  and a lower part of the respective toe portion  27  and heel portion  28  (see for example  FIGS. 2, 3, 6 and 7 ). 
     In forms of embodiment described with reference to  FIGS. 2-5 , the sport footwear  10  can comprise releasable attachment members  17  of the at least one coupling projection protection cover  15 ,  16  to the shell  11 . 
     In particular, the releasable attachment members  17  can be chosen from the group comprising screws  18  ( FIGS. 2-5 ), pegs, pins or joint elements. 
     In forms of embodiment described with reference to  FIG. 2 , the releasable attachment members  17  can also be configured to attach the contact plates  30 ,  31  to the sole  14 . In fact, for example the screws  18  that can function as releasable attachment members  17  can be positioned on the sole  14  of the shell  11 , allowing to constrain the contact plates  30 ,  31  at the same time ( FIGS. 2-5 ). 
     In possible implementations, auxiliary screws  18   a  may also be provided, to complete the attachment of the contact plates  30 ,  31  to the sole  14  ( FIGS. 2-5 ). 
     In forms of embodiment described with reference to  FIGS. 3 and 4 , at least one coupling projection protection cover  15 ,  16  has a concave seating  21  configured to be coupled with, and to receive inside it, a mating convex profile  22  provided on the toe coupling projection  12  and/or on the heel coupling projection  13 . 
       FIGS. 3 and 4  show forms of embodiment of the present invention in which the screws  18  are coupled with holes  19  passing through at least the coupling projection protection covers  15   16  and through the shell  11 . 
     In particular, the coupling projection protection covers  15 ,  16  can comprise the attachment portions  32 , configured to allow the attachment of the coupling projection protection covers  15 ,  16  to the shell  11  by means of the releasable attachment members  17 , in particular the screws  18 . 
     For example, in the forms of embodiment shown in  FIGS. 3 and 4 , the attachment portions  32  are positioned in contact with the sole  14 , that is, on the lower part of the shell  11 . In these embodiments, the holes  19  can be provided on the sole  14 , which allows to hide the screws  18  when the sport footwear  10  is worn by a user. 
     In some forms of embodiment, the thickness of the at least one coupling projection protection cover  15 ,  16  is comprised between 0.5 mm and 5 mm, in particular between 1 mm and 3 mm. 
     The reduced thickness of the coupling projection protection covers  15  and  16  allows, in the case where the attachment portions  32  are positioned in contact with the sole  14 , to keep the barycenter of the combined sport footwear  10 /ski or snowboard low, when the sport footwear  10  and the ski or snowboard are coupled. 
     The reduced thickness of the coupling projection protection covers  15  and  16  also allows to reduce the overall weight of the sport footwear  10 , even if a second material is used with a particularly high density, like some polyurethane-based or polyamide-based materials. 
     With reference to  FIGS. 3 and 4 , the holes  19  can pass not only through the coupling projection protection covers  15 ,  16  and the shell  11 , but also the contact plates  30 ,  31 , allowing to attach the latter by means of screws  18 . 
     In variant forms of embodiment, not shown, the holes  19  can be made for example on the convex profile  22  of the coupling projections  12 ,  13 . 
     In forms of embodiment described with reference to  FIG. 5 , the coupling projection protection covers  15 ,  16  can have an external profile  36  which can have a shape mating with the respective shape of the toe coupling projection  12  or heel coupling projection  13 . 
     The external profile  36  can laterally surround the respective toe coupling projection  12  or heel coupling projection  13 , and can have a covering wall or roof  34 , transverse, in particular perpendicular, to the external profile  36 , able to cover and protect the respective toe coupling projection  12  or heel coupling projection  13  from above. 
     For example, the external profile  36  can be U-shaped, for example it can be a U-shaped wall. The toe portion  27  and the heel portion  28  can have fissures or grooves  33 , mating with the covering walls  34  of the coupling projection protection covers  15 ,  16 . 
     In this way, the fissures or grooves  33  are configured mating with the covering walls  34 , to allow a reciprocal coupling and hence a stable connection to the zone of the toe coupling projection  12  and the heel coupling projection  13 . 
     In other forms of embodiment, the external profile  36  can comprise rectilinear segments and/or curved segments in alternation. 
     In forms of embodiment described with reference to  FIG. 5 , the attachment portions  32  are reduced in size, in order to further limit the overall weight of the coupling projection protection covers  15 ,  16 . 
     In this case, the attachment portions  32  have a laminar or plate-like form and comprise first holes  19   a  mating in size with the shape of the screws  18 . In particular, the attachment portions  32  can protrude or project toward the inside with respect to the external profile  36 . For example, the attachment portions  32  can be made as eyelets or annular portions, which have the first holes  19   a  inside them. 
     The holes  19  are made up in their entirety by the first holes  19   a , second holes  19   b , comprised in the shell  11 , and third holes  19   c  comprised in the contact plate  30 ,  31  ( FIGS. 3-4 ). 
     In forms of embodiment according to  FIGS. 1, 3, 4 and 5 , the shell  11  can comprise support structures  23 ,  24  configured for the attachment of the coupling projection protection covers  15 ,  16  and/or the contact plates  30 ,  31 . 
     With reference to  FIG. 5 , a first support structure  23  can be provided for example in correspondence with the toe portion  27 , and a second support structure  24 , in correspondence with the heel portion  28 . The first support structure  23  and the second support structure  24  are associated with the sole  14  of the shell  11 , in particular made protruding from the sole  14  in correspondence respectively with the lower part of the toe portion  27  and the heel portion  28 . As described with reference to  FIG. 5 , the coupling projection protection covers  15 ,  16  can be provided respectively between the first support structure  23  and the second support structure  24  and the heel contact plate  30  and the toe contact plate  31 . 
     The support structures  23 ,  24  can comprise structural ribs  35  configured to structurally support the coupling projection protection covers  15 , 16  and support the weight of a user. 
     In other forms of embodiment described using  FIGS. 6 and 7 , the first coupling projection protection cover  15  can comprise coupling means  37  for Alpine skiing, that is, configured to be coupled with bindings for Alpine skiing, for example making a binding commonly known as Dynafit®. 
     The coupling means  37  for Alpine skiing, such as for example the Dynafit® type or similar or comparable, in particular provide to maintain the toe coupling projection  12  pivoted to the ski, allowing to raise the heel portion  28  of the sport footwear  10 , by means of a rotatory movement, thus facilitating the movement required in Alpine skiing. 
     In some forms of embodiment, the coupling means  37  for Alpine skiing can be integrated in an attachment portion  38  provided at the front of the first coupling projection protection cover  15 . 
     In particular, the coupling means  37  for Alpine skiing can comprise two coupling cavities  39  made laterally, in particular in an opposite position, on the attachment portion  38  of the first coupling projection protection cover  15 . 
     In some forms of embodiment, the coupling cavities  39  can be made on attachment blocks  40 , for example comprised in a strengthening plate  41 , for example metal, which can provide the necessary structure and resistance (for example see  FIG. 7 ). 
     In other possible forms of embodiment, the coupling cavities  39  can be made on a metal bar inserted transversely in the attachment portion  38 . 
     In possible forms of embodiment, the metal plate  41  or the metal bar can be inserted, drowned or incorporated inside the first coupling projection protection cover  15 , for example during molding. 
     It is clear that modifications and/or additions of parts may be made to the sport footwear for practicing winter sports as described heretofore, without departing from the field and scope of the present invention. 
     It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of sport footwear for winter sports, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby. 
     Although the above description refers to forms of embodiment of the invention, other forms of embodiment can be provided but this does not distance it from its main field of protection, and its field of protection is defined by the claims that follow. 
     It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.