Resiliently flexible fin

Abstract

The present invention relates to a resiliently flexible fin for a surfboard or another surface watercraft, the resiliently flexible fin comprising a titanium or titanium alloy core and an opening in the trailing edge that enables a portion of the rear of the fin to resiliently flex against the force of water as the surfboard is turned, which can generate additional forward thrust for the surfboard as the surfboard exits the turn and the fin returns to its unflexed state displacing water in its path with force.

Claims

1. A resiliently flexible fin comprising: two outer fin surfaces which meet at a leading edge and a trailing edge; a mounting means for mounting the fin onto a surfboard; a core comprising metal or metal alloy; a flexible cover over at least a portion of the core; and an opening at the trailing edge through a portion of the fin; wherein the core comprises apertures, recesses, and/or cavities and the apertures, recesses, and/or cavities are filled with flexible cover.

2. The resiliently flexible fin according to claim 1, wherein the metal is titanium and the metal alloy is titanium alloy and the titanium alloy comprises between approximately 3.5% to 4.5% vanadium, and between approximately 5.5% to 6.75% aluminium.

3. The resiliently flexible fin according to claim 1, wherein the opening at the trailing edge through a portion of the fin section is a cut.

4. The resiliently flexible fin according to claim 3, wherein the cut is a substantially lateral cut.

5. The resiliently flexible fin according to claim 3, wherein the cut is adjacent to the mounting means.

6. The resiliently flexible fin according to claim 3, wherein the cut is substantially parallel to the mounting means.

7. The resiliently flexible fin according to claim 1, wherein the opening is through a portion of the core.

8. The resiliently flexible fin according to claim 1, wherein the portion of the fin on the opposite side of the opening to the mounting means can resiliently flex.

9. The resiliently flexible fin according to claim 1, wherein the flexible cover is a flexible overmoulding.

10. The resiliently flexible fin according to claim 1, wherein the mounting means are mounting blocks capable of attaching to commercially available fin plug and fin box systems.

11. The resiliently flexible fin according to claim 1, wherein in use, forces exerted by water on an outer fin surface when a rider of a surfboard on which the fin is mounted forces the surfboard to turn, flexes the portion of the fin on the opposite side of the opening to the mounting means, and upon release of the force exerted by the water as the surfboard exits the turn, the resilience of the metal or metal alloy core displaces water in its path as it returns the fin to its non-flexed configuration providing additional forward thrust for the surfboard.

12. The resiliently flexible fin according to claim 1, comprising a fin section releasably or permanently attached to a fin base portion, wherein the fin section comprises the opening and the fin base portion comprises the mounting means for mounting the fin onto a surfboard.

13. The resiliently flexible fin according to claim 1 for mounting to any one of the boards in the group comprising: surfboard, shortboard, kneeboard, longboard, minimal, soft board, kiteboard, wind surfer, stand up paddleboard, wakeboard, rescue board, bodyboard, or another board used in surface water sports or activities.

14. The process comprising the step of mounting a resiliently flexible fin according to claim 1 to any one of the boards in the group comprising: surfboard, shortboard, kneeboard, longboard, minimal, soft board, kiteboard, wind surfer, stand up paddleboard, wakeboard, rescue board, bodyboard, or another board used in surface water sports or activities.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 illustrations of: (A) a side and perspective view of a preferred embodiment of a resiliently flexible fin according to the first aspect of the invention, with mounting blocks as the mounting means that can be releasably attached within FCS II fin plugs or original FCS fin plugs; and (B) a side and perspective view of a preferred embodiment of a resiliently flexible fin according to the first aspect of the invention, with mounting blocks that can be releasably attached within FCS II fin plugs.

(2) FIG. 2 illustrations of a (A) side and (B) perspective view of a preferred embodiment of a resiliently flexible fin according to the first aspect of the invention, with a mounting block that can be releasably attached within a Futures fin box.

(3) FIG. 3 illustrations of: (A) an exploded view, (B) a side view, and (C) a perspective view, of a preferred embodiment of a resiliently flexible fin with a titanium alloy core according to the first aspect of the invention, with mounting blocks that can be releasably attached within original FCS fin plugs and FCS II fin plugs.

(4) FIG. 4 illustrations of: (A) an exploded view, (B) a side view, and (C) a perspective view, of a preferred embodiment of a resiliently flexible fin with a titanium alloy core according to the first aspect of the invention, with mounting blocks that can be releasably attached within FCS II fin plugs.

(5) FIG. 5 illustrations of: (A) an exploded view, (B) a side view, and (C) a perspective view, of a preferred embodiment of a resiliently flexible fin with a titanium alloy core according to the first aspect of the invention, with a mounting block that can be releasably attached within a Futures fin box.

(6) FIG. 6 computer generated images of: (A) a side, and (B) a perspective view, of a preferred embodiment of an adjustable, resiliently flexible fin according to the first aspect of the invention, with mounting blocks that can be releasably attached within FCS II fin plugs or original FCS fin plugs.

(7) FIG. 7 computer generated images of: (A) a side, and (B) a perspective view, of a preferred embodiment of an adjustable, resiliently flexible fin according to the first aspect of the invention, with a mounting block that can be releasably attached within a Futures fin box.

(8) FIG. 8 computer generated images of: (A) a side, and (B) a perspective view, of a preferred embodiment of an adjustable, resiliently flexible fin according to the first aspect of the invention, with a flat base for mounting the fin to a surfboard.

(9) FIG. 9 illustrations of different views of a preferred embodiment of an adjustable, resiliently flexible fin excluding the base, according to the first aspect of the invention.

(10) FIG. 10 illustrations of different views of a preferred embodiment of an adjustable, resiliently flexible fin excluding the base, according to the first aspect of the invention with an opaque overmoulding so the core is not visible.

(11) FIG. 11 illustration of a side view of a preferred embodiment of the resiliently flexible fin according to the second aspect of the invention.

(12) FIG. 12 illustration of an exploded side view of a preferred embodiment of the resiliently flexible fin according to the second aspect of the invention.

(13) FIG. 13 illustration of a side view of a preferred embodiment of the resiliently flexible fin according to the second aspect of the invention with translucent overmoulding making the core visible through the overmoulding.

(14) FIG. 14 illustration of a side view of a preferred embodiment of the core of a fin section according to the second aspect of the invention.

(15) FIG. 15 illustrations of: (A) a front view, (B) a top view, (C) a left side view, (D) a rear view, (E) a bottom view, (F) a right side view, (G) a first perspective view, and (H) a second perspective view of a fin section according to an embodiment of the second aspect of the invention.

(16) FIG. 16 illustrations of: (A) a side view, (B) a front view, and (C) an exploded perspective view of a dual fin according to the third aspect of the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

(17) Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features, compositions and compounds referred to or indicated in the specification, individually or collectively and any and all combinations or any two or more of the steps or features.

(18) The present invention is not to be limited in scope by the specific embodiments described herein, which are intended for the purpose of exemplification only. Functionally equivalent products, compositions and methods are clearly within the scope of the invention as described herein.

(19) Throughout this specification, unless the context requires otherwise, the word comprise, or variations such as comprises or comprising, will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

(20) Other definitions for selected terms used herein may be found within the detailed description of the invention and apply throughout. Unless otherwise defined, all other scientific and technical terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the invention belongs.

(21) Features of the invention will now be discussed with reference to the following preferred embodiments.

First Aspect of the Invention

(22) A preferred embodiment of the resiliently flexible fin according to the first aspect of the invention is shown in FIG. 1 and FIG. 2. The resiliently flexible fin 100 in FIG. 1A comprises mounting blocks 110 that can be releasably attached within original FCS plugs or FCS II plugs in a surfboard. The resiliently flexible fin 100 in FIG. 1B comprises mounting blocks 112 that can be releasably attached within FCS II plugs in a surfboard. The resiliently flexible fin 100 in FIG. 2 comprises a mounting block 113 that can be releasably attached within a Futures fin box in a surfboard.

(23) A lateral cut 120 from the trailing edge 114 through a portion of the fin situated close to the mounting blocks enables the upper portion 116 of the fin above the cut (that is, on the opposite side of the cut to the mounting blocks 110/112/113) to resiliently flex upon normal forces experienced during a turn while surfing a wave on a surfboard to which the fin 100 is mounted. The resilient flexing of the upper portion 116 of the fin 100 is greatest towards the trailing edge 114 and the tip 118 of the fin 100. This aims to provide additional thrust and therefore speed for the surfboard on which the fin 100 is mounted as the flexed fin returns to its un-flexed configuration.

(24) A further preferred embodiment of the resiliently flexible fin of the invention is shown in FIG. 3. Similarly to the resiliently flexible fin shown in FIG. 1A, the resiliently flexible fin 200 of FIG. 2 comprises mounting blocks 110 that can be releasably attached within original FCS plugs or FCS II plugs in a surfboard, and a lateral cut 120 from the trailing edge 114 through a portion of the fin adjacent the base. However, this embodiment of the resiliently flexible fin 200 comprises a titanium alloy core 210 within the fin 200. FIG. 3A shows an exploded version of the fin 200 with the core 210 separated from the overmoulding, plastic, or resin cover 220.

(25) As already described herein, the benefit of the titanium or titanium alloy core is to provide beneficial strength, flexibility and resilience to: (i) not break under the turning forces when in normal use, particularly with the cut 120 through the fin 200; (ii) allow the upper portion 116 of the fin 200 to flex with the turning forces the fin 200 is put under during normal use; and (iii) to return to the original configuration or shape once those turning forces have been removed.

(26) In FIG. 3B and FIG. 3C, the outline of the titanium alloy core 201 within the resiliently flexible fin 200 is indicated by dashed lines.

(27) FIG. 4 shows a resiliently flexible fin similar to the fin shown in FIG. 3 except comprising mounting blocks 112 that can be releasably attached within FCS II plugs in a surfboard.

(28) FIG. 5 shows a resiliently flexible fin similar to the fin shown in FIG. 3 and FIG. 4 except comprising a mounting block 113 that can be releasably attached within a Futures fin box in a surfboard.

(29) Further preferred embodiments of the resiliently flexible fin of the invention are shown in FIG. 6, FIG. 7, and FIG. 8. Each of these embodiments comprises a base portion 300 which is releasably attached to, and adjustable with, the fin 302, and the base portions 300 comprise either:

(30) mounting blocks 304 that can be releasably attached within original FCS plugs or FCS II plugs in a surfboard (FIG. 6), a mounting block 306 that can be releasably attached within a Futures fin box in a surfboard (FIG. 7), or a flat base 308 (FIG. 8) for mounting the resiliently flexible fin to a surfboard. These embodiments also comprise a lateral core cut 310 through a portion of the titanium alloy core 312, in addition to a cut 314 through the transparent overmoulding 316 covering the core 312.

(31) FIG. 9 shows different views of line drawing illustrations of a fin, excluding the base portion, according to the preferred embodiments in FIG. 6, FIG. 7, and FIG. 8.

(32) FIG. 10 shows different views of line drawing illustrations of a fin, excluding the base portion, similar to the embodiment shown in FIG. 9 except the titanium alloy core cannot be seen beneath a flexible overmoulding cover that is opaque.

Second Aspect of the Invention

(33) A preferred embodiment of a flexible fin according to the second aspect of the invention is shown in FIG. 11. The fin section 10 comprises a leading edge 12 and a trailing edge 14 and outer fin surfaces 16 of which only one is visible in the side view of FIG. 11. The fin section 10 is attached to the fin base 20 at the base attachment surface 22

(34) Three lateral cuts 30 approximately two thirds through the fin section 10 begin at the trailing edge 14 and are substantially parallel to the base attachment surface 22. The cuts 30 form resiliently flexible trailing edge flaps 32. When the flexible fin is mounted onto a surfboard, a rider turning the surfboard during normal use will cause forces applied by the water to flex the trailing edge flaps 32. Without wanting to be limited by theory, it is understood that as the surfboard and rider is exiting the turn, the resilient trailing edge flaps 32 return to their original position (and even momentarily beyond) with the reduction and release of those water forces. The strength and resilience of the titanium or titanium alloy core 40 when returning to the original position causes a direct force on the water in the substantially opposite direction giving the surfboard and rider additional speed at the end of the turn in a substantially forward direction. These resilient trailing edge flaps 32 are considered by the inventor to replicate the effect of a hinged door-like effect. This is particularly beneficial if the turn is a bottom turn up toward the lip of a wave wherein the additional speed generated by the trailing edge flaps 32 can assist the surfboard and rider further into the air above the lip to perform an aerial manoeuvre.

(35) The preferred embodiment of the flexible fin according to the second aspect of the invention is shown in an exploded form in FIG. 12. The fin section 10 comprising the cuts 30 is attached to the fin base 20 at the base attachment surface 22 with base attachment tabs 24 which fit into accommodating slots in the top of the fin base 20. The fin section 10 may be permanently attached to the fin base 20 or releasably attachable so the fin sections may be interchanged with a different fin section, for example, that has a different fin template. Alternatively, fin sections according to the invention having different fin templates may be attached to the same type of fin base during manufacture. The fin base 20 in the preferred embodiment comprises at least two distinct portions.

(36) The fin section 10 comprises a core 40 of titanium or titanium alloy which is covered by a flexible over-moulding 50 as shown in FIG. 13. The core 40 in the preferred embodiment comprises a plurality of circular or oval holes 42. A first purpose of these holes 42 is to assist the flexibility of the titanium or titanium alloy core 40. In this regard, the holes 42 are relatively small adjacent to the leading edge 12 and are larger in size towards the trailing edge 14. This creates a stronger and stiffer core 40 in the vicinity of the leading edge 12 and enables greater flexibility of the core 40 adjacent the trailing edge. The largest holes 42 in the core 40 are within the trailing edge flaps 32 which provides this region of the fin section with the greatest flexibility. An additional benefit is a reduction in the weight of the core (although the titanium and titanium alloy core is not heavy relative to the other materials fins are usually constructed from), as well as a reduction in the amount of costly titanium or titanium alloy required to form the core 40.

(37) The flexible overmoulding 50 covers the core 40 and forms the template of the fin section 10. A portion of overmoulding 50 at the leading edge 12 and fin tip 16 covers the core 40 to maintain the safety of the surfboard rider and other persons that could potentially come into contact with the leading edge 12 or fin tip 16 of the flexible fin of the invention when in use.

(38) The overmoulding 50 does not cover the base attachment surface 22, base attachment tabs 24, or any other base mounting means. Instead the core 40 attaches to the fin base 20.

(39) A second purpose for the holes 42 in the core 40 is that they are filled with overmoulding 50 providing strong attachment between the core 40 and overmoulding 50.

(40) A cut 30 begins through overmoulding 50 from the trailing edge 14 and passes through a portion of the core 40 until the cut 30 ends at a cut end hole 44. Finishing the cut in a cut end hole 44 reduces the potential for unwanted lengthening of the cut 30 further into the core 40 during use of the flexible fin.

(41) FIG. 14 shows just the titanium or titanium alloy core 40 which highlights that the base attachment surface 22 extends to the leading edge 12 and trailing edge 14 of the fin section 10. It also more clearly shows the increasing size of the holes 42 towards the trailing edge 14.

(42) FIG. 15 shows alternative views of a fin section according to an embodiment of the invention according to the second aspect with opaque overmoulding so that the core is not visible.

Third Aspect of the Invention

(43) A preferred embodiment of the flexible fin according to the third aspect of the invention is shown in FIG. 16, wherein a second fin section 60 is attached to the fin section 10 by an attachment means. The attachment means in this embodiment are in the form of three ribs 62 configured in the shape of a cross section of a foil, which are attached to the second fin section 60. The ribs 62 form a thin gap between the fin section 10 and the second fin section 60 through which water can pass during normal use. The second fin section 60 has a thinner template than the fin section 10 with the whole second fin section 60 located adjacent the leading edge 12 of the fin section 10. The second fin section 60 is attached to the fin section 10 by two screws 64 through each rib 62 and the two screws pass through holes in the fin section 10. Openings in the form of a gap 66 and holes 67 in the second fin section allow water to pass through the second fin section 60 during normal use and direct that water to the area adjacent the trailing edge 68 of the second fin section 60. Without wanting to be limited by theory, it is understood that increased pressure in this area due to the additional water directed into this area, when compared to the lower pressure adjacent the leading edge 12 of the fin section 10 and the leading edge 69 of the second fin section 60, causes thrust in a direction towards the area of lower pressure and therefore the leading edge 12 of the fin section 10 and the front of the surfboard.