Fin for underwater activities

Abstract

 A fin for underwater activities, which comprises at least one foot pocket (2) provided with an upper (3), made of substantially soft and lightweight material suitable to provide excellent fit comfort and fixed to a sole (4) made of rigid material, and at least one blade (5), which is associated with the sole by way of respective means for rigid coupling which may also be detachable, the blade (5) comprising at least one coupling portion (5a) whose shape is substantially complementary to the shape of a respective seat (6) formed within the rigid sole (4), so as to minimize the loss of energy and achieve optimum propulsion thrust.

Description

[0001] The present invention relates to a fin for underwater activities.

[0002] Currently, the number of people, ranging from mere amateurs to professionals, who practice underwater activities, such as scuba diving, breath-hold diving and breath-hold fishing, performed both at sea and in fresh water, is large and is indeed constantly increasing, and the number of those who practice water sports such as swimming with fins, and others, is also increasing.

[0003] When performing these activities, thrust for propulsion is notoriously achieved by divers by using suitable fins worn on the feet: the fin traditionally comprises a foot pocket, in which the foot is inserted and which is associated with a respective blade which is generally elongated and flat. The blade, which when pushed by the foot (by virtue of the muscle action mainly of the legs and buttocks) against the water is subjected to a flexural load, allows the forward motion of the user with a speed which varies depending on the muscular effort and on the breadth and rate of fin motion.

[0004] Particularly for diving and fishing performed in apnea (a discipline which is becoming increasingly popular), fins have a role of primary importance among equipment dedicated to these activities, not only in terms of performance but also in terms of safety.

[0005] The breath-hold diver and fisher in fact use only their muscle power for underwater and surface movements, and when diving they can rely only on the air contained in their lungs. For these reasons, fins must allow them to move at a good speed and with the least possible energy expenditure: for this purpose, it is important for the blade to have high-level mechanical characteristics (and in particular an excellent elastic response, so that the energy dissipated during flexural deformation of the blade is minimal), and at the same time the blade must be adequately flexible, in order to avoid tiring the muscles of the user, and tough.

[0006] Known types of foot pocket are made of substantially soft material with calibrated deformability, traditionally rubber of various kinds, in order to allow insertion of the foot from above through a suitable opening and ensure a certain comfort of the fit. However, the operations for inserting the foot in the foot pocket are not particularly quick and comfortable to perform for the user.

[0007] The fit of these foot pockets is generally unique, i.e., equal both for the right foot and for the left foot (this single fit is also termed "ambidextrous"). Therefore, the foot pocket may not adhere adequately to the user's foot and the play that occurs between the foot and the foot pocket contribute negatively to the dissipation of energy when swimming with fins and can also cause abrasions of the foot due to friction against the rubber. The use of this material, moreover, makes the foot pocket very heavy, with negative consequences in terms of fatigue of the muscle regions involved in swimming with fins.

[0008] The blade can be provided monolithically together with the foot pocket (by molding) or can be provided separately and associated with the foot pocket in a second step and therefore can be made of materials of a different type.

[0009] For example, the blade is made of polymeric material, which however does not have the best mechanical characteristics useful for the purpose, since it has a limited elastic response and consequently dissipates much of the muscle power during the flexing of said blade.

[0010] It is therefore known to resort to materials which have better mechanical characteristics than those of polymeric materials, such as composite materials made of engineered fibers (such as carbon, glass or Kevlar) embedded in a resin matrix. In particular, blades made of composite material such as carbon fiber embedded in a resin matrix have a high efficiency and an extremely low energy dissipation by virtue of the excellent elastic response of this material.

[0011] The blade has a coupling end, which is inserted in a suitable receptacle of the foot pocket, from the sides of which two longitudinal members protrude at the front which are provided with guides within which the sides of the blade are inserted by interlocking for a limited extent. The blade and the foot pocket are then mutually fixed, generally by way of means of the screw type.

[0012] However, the mating between the blade and the foot pocket occurs over a small surface, and since the foot pocket is further made of soft material, the mating is not very rigid: accordingly, dissipation of muscle power when swimming with fins is high, due to the deformation of the foot pocket and to the mating which is, as mentioned, not very rigid.

[0013] As shown, known types of fin have drawbacks which lead to their poor efficiency, with high energy dissipations, leading to a less than ideal propulsion thrust for the user.

[0014] Further, as described, the voids between the foot and the foot pocket can cause the onset of fatigue and even pain of the foot when swimming with fins, caused also by the substantial weight of the foot pocket made of rubber, so much as to force the user to a slower stroke or even to interrupt the practice of the underwater activity.

[0015] Moreover, the materials traditionally used to provide the foot pocket are not soft enough to prevent, together with the friction due to the voids between the foot and the foot pocket, the onset of blisters and/or abrasions, and therefore during prolonged use it is practically mandatory to use boots in order to avoid the problem.

[0016] Moreover, insertion of the foot in the foot pocket through said opening is not particularly easy and the fit is scarcely comfortable.

[0017] The aim of the present invention is to solve the above mentioned problems, by providing a fin for underwater activities which is comfortable, i.e., can be worn easily and comfortably, is lightweight, and avoids the onset of foot fatigue or even pain during its use, even if it is prolonged.

[0018] Within this aim, an object of the present invention is to provide a fin which allows to minimize energy losses by providing a significantly higher efficiency than known types of fin, so as to achieve optimum propulsion thrust for the user.

[0019] Another object of the present invention is to provide a fin which, thanks to its particular constructive characteristics, is capable of giving the greatest assurances of reliability and safety in use.

[0020] Another object of the present invention is to provide a fin which is simple, relatively easy to provide in practice, safe in use, effective in operation, and also competitive from an economic standpoint.

[0021] This aim and these and other objects which will become better apparent hereinafter, are achieved by a fin for underwater activities, characterized in that it comprises at least one foot pocket provided with an upper, made of substantially soft and lightweight material suitable to provide excellent fit comfort and fixed to a sole made of rigid material, and at least one blade, which is associated with said sole by way of respective means for rigid coupling which may also be detachable, said blade comprising at least one coupling portion whose shape is substantially complementary to the shape of a respective seat formed within said rigid sole, so as to minimize the loss of energy and achieve optimum propulsion thrust.

[0022] Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment of a fin for underwater activities, according to the invention, illustrated by way of non-limiting example in the accompanying drawings, wherein:

Figure 1 is a top view of a fin for underwater activities according to the invention;

Figure 2 is a bottom view of a fin for underwater activities according to the invention;

Figure 3 is an exploded side view of a fin for underwater activities according to the invention;

Figure 4 is a bottom view of a foot pocket of the fin which highlights the sole, according to the invention.

[0023] With reference to the figures, the reference numeral 1 generally designates a fin for underwater activities according to the invention.

[0024] The fin 1 comprises at least one foot pocket 2 which has an upper 3, which is made of substantially soft and lightweight material suitable to provide optimum fit comfort and is fixed to a sole 4 made of rigid material, and at least one blade 5, which is associated with the sole 4 by way of respective rigid coupling means which can also be detachable. The blade 5 comprises at least one coupling portion 5a, whose shape is substantially complementary to the shape of a respective seat 6 formed in the rigid sole 4, so as to minimize the loss of energy and achieve optimum propulsion thrust.

[0025] Conveniently, the foot pocket 2 comprises closure elements, which are adapted to fasten suitably the upper 3 around the foot of the user, so as to avoid the formation of disadvantageous voids between the foot pocket and the foot and minimize energy loss.

[0026] The front region of the rigid sole 4 comprises a protrusion 8, which protrudes at least from the sides of the tip of the foot pocket 2, and the seat 6 is formed at the front region of the sole 4.

[0027] In greater detail, the blade 5 comprises a first flat end portion 9 and a second flat portion 10 which has a free tip 10a and cantilevers out from the foot pocket 2 when the blade 5 is associated with the sole 4: the first portion 9 and the second portion 10 are mutually inclined, and a connecting region 11 with a preset radius of curvature is formed between them.

[0028] The coupling portion 5a comprises at least the first portion 9 and the connecting region 11, which is accommodated at the front in the seat 6, substantially proximate to the protrusion 8. In greater detail, the coupling portion 5a comprises the first portion 9, the connecting region 11 and an initial region of the second portion 10, and the seat 6 accommodates the connecting region 11 and the initial region of the second portion 10 at the front, substantially at the protrusion 8.

[0029] Further, the coupling portion 5a is affected by a distribution of through holes 12 and the sole 4 is affected, at the seat 6, by openings 13 and by at least one slot 14, which are located correspondingly with respect to the holes 12, for the detachable rigid locking of the blade 5 to the foot pocket 2 by way of the coupling means.

[0030] In particular, two of the holes 12 are arranged, in a configuration for mating the blade 5 with the foot pocket 2, at two respective through openings 13, which are provided substantially on the protrusion 8 of the sole 4 substantially at the sides of the tip of the foot pocket 2, and at least one other hole 13, and preferably three other holes 13, are arranged at three respective slots 14 located in the seat 6 substantially below the region on which the forefoot rests. Conveniently, said coupling means comprise at least one plurality of threaded elements 15, which can engage in the holes 12, in the slots 14 and in the through openings 13 for the detachable rigid locking of the blade 5 to the foot pocket 2.

[0031] Preferably, the coupling means comprise at least two screws 15, which can be inserted in the two through openings 13 and in the two corresponding holes 12 and can engage two respective locking nuts 16, and further comprise at least three other screws 15, which can be inserted in three additional holes 12 and in three corresponding slots 14 and can engage three additional respective nuts contained in receptacles formed within the sole 4 and connected to the slots 14 (the additional three nuts and the receptacles are not visible in the figures). As mentioned, these last slots 14 are located in the seat 4, substantially below the region on which the forefoot rests, and in greater detail are arranged (and so are the respective three holes 12 on the coupling portion 5a) at the vertices of a triangle whose vertex is oriented toward the heel of the foot pocket 2.

[0032] Advantageously, the coupling means further comprise at least one substantially plate-like element 17, which is made of rigid material, has a shape which is substantially complementary to the shape of the coupling portion 5a, and is affected by a plurality of orifices 18 which are distributed so as to correspond to the holes 12 of the coupling portion 5a: positively, said portion is clamped detachably by means of the screws 15 between the substantially plate-like element 17 and the sole 4, so as to ensure an optimum rigid coupling between the blade 5 and the sole 4 of the foot pocket 2.

[0033] In particular, the protrusion 8 has a substantially isosceles trapezoid plan shape and protrudes from the tip of the foot pocket 2 laterally with the oblique sides and at the front with the longer parallel side; the two through openings 13 are provided at the oblique sides.

[0034] Further, the protrusion 8 is affected by a substantially central weight reduction cutout 19, which extends partially below the tip of the foot pocket 2; the longer parallel side, which closes it at the front, gives it greater structural rigidity.

[0035] The closure elements 7 are of the adjustable type, so as to allow optimum fastening of the right and left flaps of the upper 3 around the foot of the user, and in particular comprise at least one strap 20, and preferably a plurality of straps 20 (for example two, as shown in Figure 1 and in Figure 3) with fastening of the Velcro type. Nevertheless, in other exemplary embodiments the closure elements 7 may also comprise laces or other fastening elements traditionally used with technical and sports footwear of a known type (and, like these last, the foot pocket 2 can comprise or not a tongue).

[0036] Adequately, the foot pockets 2 have a first configuration which is suitable for fitting a right foot and a second configuration which is suitable for fitting a left foot, so as to adhere perfectly and comfortably to the feet of the user, minimizing the losses of energy that are instead high when using traditional fins due to foot pockets which have a so-called "ambidextrous" fit.

[0037] The sole 4, which as mentioned is conveniently rigid, can be made of polymeric material for example such as nylon loaded with glass fibers.

[0038] As an alternative, the sole 4 can be made of composite material, for example of the type of carbon fiber (or glass fiber or Kevlar or other engineered fibers) embedded in a resin matrix.

[0039] The blade 5 can be made of the materials normally used for traditional blades, but it is preferably made of composite material, for example of the type of carbon fiber embedded in a resin matrix, which notoriously has a high elastic response, higher than the other materials normally used, and ensures excellent efficiency of the fin and minimum energy expenditure for the user when swimming with fins.

[0040] Nevertheless, the blade 5 can also be made of a composite material such as glass fiber (or also Kevlar or other engineered fibers) embedded in a resin matrix and, as mentioned, in even other materials.

[0041] The blade 5, and particularly the coupling portion 5a, have an adequate thickness in order to withstand the mechanical stresses to which they are subjected when swimming with fins.

[0042] The rigid substantially plate-like element 17 also can be made of polymeric material, for example of the type of nylon loaded with glass fibers, or composite material, for example of the type of carbon fiber (or glass, or Kevlar or other engineered fibers) embedded in a resin matrix, and even other materials.

[0043] The upper 3, as mentioned, is made of substantially soft material, for example technical synthetic fabric, such as for example the fabric known by the registered name Cordura (registered trademark), which has high mechanical characteristics of strength and low weight, or also synthetic leather (imitation leather) and other materials normally used to provide the uppers of known types of technical-sports footwear. For this reason, the upper 3, fastened by virtue of the closure elements 19, adheres perfectly to the foot of the user, adapting positively to the shape of said foot and thus avoiding the onset of fatigue, pain or abrasions, even after prolonged use. The use of these materials advantageously allows to provide foot pockets 2 which are lightweight and therefore lighter than traditional foot pockets made of rubber, with advantages also in terms of reduced fatigue of the muscle areas involved in swimming with fins. Effectively, the comfort thus ensured by the foot pocket 2 allows the user to wear the fins 1 even without boots.

[0044] Further, the shape of the foot pocket 2 of the technical-sports type facilitates effectively the insertion of the foot in the foot pocket 2, contrary to what occurs with foot pockets of known types of fin.

[0045] The upper 3 and the sole 4 are fixed to each other by adhesive bonding and preferably also by means of rivets 20 which are distributed peripherally at least in the rear region and in the central region of the sole 4, as shown in Figure 4.

[0046] In a particular embodiment, known as monofin and not shown in the figures, the fin comprises two foot pockets 2 (one for inserting a right foot and one for inserting the left foot), which are associated with a single blade which comprises two respective coupling portions and has an adequate width, which is greater than that of the blade 5 which can be coupled to a single foot pocket.

[0047] In practical operation, the user easily inserts, as mentioned, his/her feet in the foot pockets 2 and fastens the flaps of the respective uppers 3 firmly and comfortably on said feet by means of the described closure elements 7, so that there can be no play between the feet and the foot pockets 2; said foot pockets, by way of the soft and light material used to provide the upper 3, are effectively comfortable and lightweight, avoid the onset of foot fatigue or even pain during fin swimming, even after prolonged use of the fin, without the breath-hold diver being forced to slow down his/her action or even interrupt the practice of underwater activity as may occur when using fins of the known type provided with foot pockets.

[0048] Further, as shown, the upper 3 and the sole 4 are rigidly fixed to each other, and the blade 5 also is rigidly coupled to the sole 4 by means of said rigid coupling means: therefore, the muscular effort applied by the user when swimming with fins is transmitted in an optimum manner to the blade 5, minimizing energy losses (which are otherwise typically high in traditional fins and are caused by plays between the foot and the foot pocket, by the materials of which said foot pockets are made, or by the limited rigidity of the coupling between the blade and the foot pocket). This allows the user to achieve optimum propulsion thrust, at the same time reducing energy expenditure when swimming with fins, to the full benefit also of safety, since the exercise of underwater activity with the fins 1 is performed predominantly by breath-hold divers and fishers.

[0049] The advantages achieved by the described fin 1 are therefore evident also by virtue of the foot pocket 2 of technical-sports derivation, which comprises the upper 3 made of soft and lightweight material and the rigid sole 4 with which it is possible to associate the blade 5, the foot pocket 2 being evidently different from foot pockets of known types of fin; for the reasons described above, the comfort and efficiency of the fin 1 according to the invention are effectively far greater than those of the traditional type.

[0050] In practice it has been found that the invention fully achieves the intended aim and objects.

[0051] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent ones.

[0052] In the exemplary embodiments shown, individual characteristics, given in relation to specific examples, may actually be interchanged with other different characteristics that exist in other exemplary embodiments.

[0053] Moreover, it is noted that anything found to be already known during the patenting process is understood not to be claimed and to be the subject of a disclaimer.

[0054] In practice, the materials used, as well as the shapes and dimensions, may be any according to requirements and to the state of the art without thereby abandoning the scope of the protection of the appended claims.

[0055] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.

Claims

1. A fin for underwater activities, characterized in that it comprises at least one foot pocket (2) provided with an upper (3), made of substantially soft and lightweight material suitable to provide excellent fit comfort and fixed to a sole (4) made of rigid material, and at least one blade (5), which is associated with said sole by way of respective means for rigid coupling which may also be detachable, said blade (5) comprising at least one coupling portion (5a) whose shape is substantially complementary to the shape of a respective seat (6) formed within said rigid sole (4), so as to minimize the loss of energy and achieve optimum propulsion thrust.

2. The fin for underwater activities according to claim 1, characterized in that said foot pocket (2) comprises closure elements (7) for the suitable fastening of said upper (3) around the foot of the user, so as to minimize energy loss and achieve optimum propulsion thrust.

3. The fin according to one or more of the preceding claims, characterized in that the front region of said rigid sole (4) comprises at least one protrusion (8) which protrudes at least from the sides of the tip of said foot pocket (2), and in that said seat (6) is formed at said front region of said sole (4).

4. The fin according to one or more of the preceding claims, characterized in that said blade (5) comprises a first flat end portion (9) and a second flat portion (10) with a free tip (10a), which cantilevers out from said foot pocket (2) when said blade (5) is associated with said sole (4), said first portion (9) and said second portion (10) being mutually inclined, a connecting region (11) being formed between said first portion (9) and said second portion (10) and having a preset radius of curvature, said coupling portion (5a) comprising at least said first portion (9) and at least said connecting region (11), said seat (6) accommodating at least said connecting region (11) at the front, substantially proximate to said protrusion (8).

5. The fin according to one or more of the preceding claims, characterized in that said coupling portion (5a) comprises said first portion (9), said connecting region (11) and an initial region of said second portion (10), said seat (6) accommodating said connecting region (11) and the initial region of said second portion (10) at the front, substantially at said protrusion (8).

6. The fin according to one or more of the preceding claims, characterized in that said coupling portion (5a) is affected by a distribution of through holes (12) and said sole (4) is affected, at said seat (6), by openings (13) and by at least one slot (14) which are located correspondingly with respect to said holes (12), for the detachable rigid locking of said blade (5) to said foot pocket (2) by way of said coupling means.

7. The fin according to one or more of the preceding claims, characterized in that at least two of said holes (12) are arranged, in a configuration for coupling said blade (5) to said foot pocket (2), at at least two respective through openings (13) which are provided substantially laterally on said protrusion (8) of said sole (4), at least one other hole (12) being arranged at at least one respective slot (14) which is located within said seat (6) substantially below the region on which the forefoot rests, said coupling means comprising at least one plurality of threaded elements (15) which can engage in said holes (12), in said at least one slot (14) and in said through openings (13), for the detachable rigid locking of said blade (5) to said foot pocket (2).

8. The fin according to claim 7, characterized in that said coupling means comprise at least two screws (15), which can be inserted in said two through openings (13) and in said two corresponding holes (12) and can engage two respective locking nuts (16), and comprise at least three additional screws (15), which can be inserted in three additional holes (12) and in three corresponding slots (14) and can engage three additional respective nuts contained in receptacles formed in said sole (4) and connected to said slots (14), said slots being located in said seat (6) substantially below the region on which the forefoot rests, for the removable rigid locking of said blade (5) to said foot pocket (2).

9. The fin according to one or more of the preceding claims, characterized in that said coupling means comprise at least one substantially plate-like element (17) made of rigid material, said substantially plate-like element (17) being shaped substantially complementarily with respect to said coupling portion (5a) and being affected by a plurality of orifices (18) which are distributed so as to correspond to said holes (12) of said coupling portion (5a), said coupling portion being fastened detachably by way of said screws (15) between said substantially plate-like element (17) and said sole (4).

10. The fin according to one or more of the preceding claims, characterized in that said protrusion (8) has a substantially isosceles trapezoid plan shape and protrudes from the tip of said foot pocket (2) laterally with the oblique sides and at the front with the longer parallel side, said openings (13) being provided proximate to said oblique sides.

11. The fin according to claim 9, characterized in that said protrusion (8) is affected by a substantially central cutout (19) for weight reduction which extends partially below said tip of said foot pocket (2).

12. The fin according to one or more of the preceding claims, characterized in that said closure elements (7) are of the adjustable type for optimum fastening of said upper (3) around the foot of the user.

13. The fin according to one or more of the preceding claims, characterized in that said closure elements (7) comprise at least one strap with fastening of the Velcro type.

14. The fin according to one or more of the preceding claims, characterized in that said foot pockets (2) have at least one first shape which is suitable for inserting a right foot and at least one second shape which is suitable for inserting a left foot.

15. The fin according to one or more of the preceding claims, characterized in that said upper (3) is made of synthetic engineered fabric, so as to ensure optimum fit comfort and provide a foot pocket (2) which is lighter than foot pockets of the traditional type.

16. The fin according to one or more of the preceding claims, characterized in that said upper (3) is made of synthetic leather, so as to ensure optimum fit comfort and provide a foot pocket (2) which is lighter than foot pockets of the traditional type.

17. The fin according to one or more of the preceding claims, characterized in that said sole (4) is made of polymeric material.

18. The fin according to one or more of the preceding claims, characterized in that said sole (4) is made of polymeric material such as nylon filled with glass fibers.

19. The fin according to one or more of the preceding claims, characterized in that said sole (4) is made of composite material.

20. The fin according to one or more of the preceding claims, characterized in that said sole (4) is made of a composite material such as carbon fiber embedded in a resin matrix.

21. The fin according to one or more of the preceding claims, characterized in that said blade (5) is made of composite material.

22. The fin according to one or more of the preceding claims, characterized in that said blade (5) is made of a composite material such as carbon fiber embedded in a resin matrix.

23. The fin according to one or more of the preceding claims, characterized in that said sole (4) is fixed to said upper (3) at least by adhesive bonding.

24. The fin according to one or more of the preceding claims, characterized in that said sole (4) is fixed to said upper (3) by means of a peripheral distribution of rivets (20).

25. The fin according to one or more of the preceding claims, characterized in that it comprises two of said foot pockets (2) associated with a blade which comprises two respective coupling portions (5a) and has an adequate width, which is greater than the width of said blade (5) which can be coupled to a single foot pocket (2).

Drawing