Fin

Abstract

A fin (10) comprising a base portion (12) attachable to a lower surface of a watercraft and a body (14) of the fin (10) extending away from the base portion (12). A pin (22) is provided connecting the base portion (12) to the body (14), the pin (22) extending outwardly away from the lower surface of the watercraft. An intermediate portion (22) is provided being resilient and flexible relative to the body (14) and the base portion (12) and extending along at least a portion of the length of the fin (10) connecting the base portion (12) to the body (14) such that the body (14) may pivot about the base portion (12) by flexing of the intermediate portion (22).

Description

“Fin”Field of the Invention

[0001] The present invention relates to a fin for a watercraft, such as a surfboard.Background to the Invention

[0002] Surfboard fins may be provided in a range of shapes and orientations. Relatively small changes in the shape of a fin can have noticeable impact on the handling of the board. Shape, size, orientation and flexibility all affect how a board will manoeuvre in various conditions.

[0003] As a surfboard turns, it experiences forces which will tend to make the fin want to twist. The present invention provides a fin which will be allowed to slightly change orientation under such conditions in a manner which is expected to improve the turning performance of the board on which the fins are installed.Summary of the Invention

[0004] According to one aspect of the present invention there is provided a fin comprising: a base portion attachable to a lower surface of a watercraft; a body of the fin extending away from the base portion; a pin connecting the base portion to the body, the pin extending outwardly away from the lower surface of the watercraft; and an intermediate portion being resilient and flexible relative to the body and the base portion and extending along at least a portion of the length of the fin connecting the base portion to the body such that the body may pivot about the base portion by flexing of the intermediate portion.

[0005] Preferably the pin is located between the leading edge and a centre of the base portion.

[0006] Preferably the pin is received in aligned holes in the base portion, the body and the intermediate portion.

[0007] Preferably the pin is oriented perpendicular to a longitudinal axis of the base portion.

[0008] Preferably the intermediate portion includes a first side fixed to an outer surface of the base portion and a second side fixed to an end surface of the body.

[0009] In a preferred embodiment, a rotation limiter is provided to limit the degree to which the body may pivot about the pin relative to the base portion.

[0010] Preferably the rotation limiter comprises a rod received in aligned bores in the base portion, the intermediate portion and the body, located between the pin and rear ends of the base portion and the body.

[0011] Preferably the bores are wider than the diameter of the pin to allow movement of the body relative to the base portion and wherein a compressible sleeve is provided around the rod.

[0012] In a preferred embodiment, the first and second sides of the intermediate portion include protruding portions received in corresponding apertures in the outer surface of the base portion and the end surface of the body.

[0013] Preferably the end surface of the body includes a recess into which a portion of the intermediate portion is received.

[0014] In one embodiment, the intermediate portion extends from adjacent a leading edge of the body to a location between the leading edge and the trailing edge of the body.

[0015] In one embodiment, the intermediate portion comprises a first side portion located adjacent the base portion, a second side portion located adjacent the body and a connecting portion extending between the first andsecond side portions such that the shape of the first side portion corresponds to the shape of the adjacent outer surface of the base portion and the shape of the second side portion corresponds to the shape of the adjacent end surface of the body.

[0016] In one embodiment, the connecting portion is U-shaped in cross sections taken perpendicular to the plane of the fin.

[0017] In one embodiment, the connecting portion is generally linear in cross sections taken perpendicular to the plane of the fin.

[0018] In one embodiment, the connecting portion extends from a first edge of the first side portion to a opposite second edge of the second side portion such that the intermediate portion is Z-shaped in cross sections taken perpendicular to the plane of the fin.

[0019] In one embodiment, the connecting portion extends from a central location on the first side portion to a central location on the second side portion such that the intermediate portion is generally l-shaped in cross section.Brief Description of the Drawings

[0020] The invention will now be described, by way of example, with reference to the following drawings, in which:

[0021] Figure 1 is an upper perspective view of a fin in accordance with the present invention;

[0022] Figure 2 is a lower perspective view of the fin of Figure 1 ;

[0023] Figure 3 is a side view of the fin of Figure 1 ;

[0024] Figure 4 is a side cross sectional view of the fin of Figure 1 ;

[0025] Figure 5a is a front view of the fin of Figure 1 ;

[0026] Figure 5b is a close up view of Detail A of Figure 5a;

[0027] Figure 6a is a rear view of the fin of Figure 1 ;

[0028] Figure 6b is a close up view of Detail B of Figure 6a;

[0029] Figure 7a is a lower view of the fin of Figure 1 ;

[0030] Figure 7b is a close up view of Detail C of Figure 7a;

[0031] Figure 8 is an exploded view of the fin of Figure 1 ;

[0032] Figure 9a is a top view of the fin of Figure 1 in a first rotated position;

[0033] Figure 9b is a top view of the fin of Figure 1 in a second rotated position;

[0034] Figure 10 is an upper perspective view of a second embodiment of a fin in accordance with the present invention;

[0035] Figure 11 is a lower perspective view of the fin of Figure 10;

[0036] Figure 12 is a side cross sectional view of the fin of Figure 10;

[0037] Figurel 3a is a front view of the fin of Figure 10;

[0038] Figure 13b is a close up view of Detail A of Figure 13a;

[0039] Figure 14a is a lower view of the fin of Figure 10;

[0040] Figure 14b is a close up view of Detail B of Figure 14a;

[0041] Figure 15 is an exploded view of the fin of Figure 10;

[0042]

[0043] Figure 16 is an upper perspective view of a third embodiment of a fin in accordance with the present invention;

[0044] Figure 17 is a lower perspective view of the fin of Figure 16;

[0045] Figure 18 is a side view of the fin of Figure 16;

[0046] Figure 19 is a side view of the fin of Figure 16 showing internal features;

[0047] Figure 20a is a rear view of the fin of Figure 16;

[0048] Figure 20b is a close-up view of Detail A of Figure 20a;

[0049] Figure 21 is an exploded view of the fin of Figure 16;

[0050] Figure 22 is an upper perspective view of a fourth embodiment of a fin in accordance with the present invention;

[0051] Figure 23 is a side view of the fin of Figure 22 showing internal features;

[0052] Figure 24a is a rear view of the fin of Figure 22;

[0053] Figure 24b is a close-up view of Detail C of Figure 24a;

[0054] Figure 25 is an exploded view of the fin of Figure 22;

[0055] Figure 26 is an upper perspective view of a fifth embodiment of a fin in accordance with the present invention;

[0056] Figure 27 is a lower perspective view of the fin of Figure 26;

[0057] Figure 28 is a side view of the fin of Figure 26 showing internal features;

[0058] Figure 29a is a rear view of the fin of Figure 26;

[0059] Figure 29b is a close-up view of Detail D of Figure 29a;

[0060] Figure 30 is an exploded view of the fin of Figure 26;

[0061] Figure 31 is an upper perspective view of the fin of Figure 26 in a rotated position;

[0062] Figure 32 is a top view of the fin of Figure 31 ;

[0063] Figure 33 is a bottom view of the fin of Figure 31 ;

[0064] Figure 34a is a rear view of the fin of Figure 31 ;

[0065] Figure 34b is a close-up view of Detail A of Figure 34a;

[0066] Figure 35a is a front view of the fin of Figure 31 ;

[0067] Figure 35b is a close-up view of detail b of Figure 35a;

[0068] Figure 36 is an upper perspective view of a sixth embodiment of a fin in accordance with the present invention;

[0069] Figure 37 is a side view of the fin of Figure 36 showing internal features; and

[0070] Figure 38 is an exploded view of the fin of Figure 36.Detailed Description of Preferred Embodiments

[0071] Referring to the Figures, there is shown a fin 10 comprising generally a base portion 12 and a body 14. The base portion 12 comprises the portion of the fin 10 to be secured to a lower surface of a watercraft such as a surfboard. In the embodiment shown, the base portion 12 includes a pair of tabs 16 to be received into an opening in a standard fin box of the type commonly used on surfboards. The tabs 16 may be received into the fin box in order to secure the fin 10 to the surfboard.

[0072] The body 14 comprises a generally known shape of a fin having a leading edge 18 and trailing edge 19 both extending upwardly away from the base portion 12. The base portion 12 includes an outer surface 50, being the surface of the base portion 12 facing outwardly away from the surface of the watercraft to which the fin 10 is attached. The outer surface 50 is therefore located adjacent the body 14 of the fin 10 in use. The body 14 of the fin 10 includes an end surface 52, being the surface located adjacent the watercraft in use. The end surface 52 of the body 14 is therefore located adjacent the outer surface 50 of the base 12 in use. Each of the outer surface 50 of the base 12and the end surface 52 of the body 12 includes a forward end 54 and a rear end 56. The forward end 54 of the end surface 52 of the body 14 connects to an end of the leading edge 18. The rear end 56 of the end surface 52 of the body 14 connects to an end of the trailing edge 19.

[0073] The base portion 12 and the body 14 are formed from a relatively rigid material, such as a plastic or fibreglass material. The fin 10 includes also a flexible intermediate portion 20 connecting between the base portion 12 and the body 14. The intermediate portion 20 is formed of a material which is relatively flexible in comparison to the base portion 12 and the body 14. The intermediate portion 20 may be formed from a suitably flexible plastic or rubber based material. The flexible intermediate portion 20 includes a first side 60 which connects to the outer surface 50 of the base portion 12 and a second side 62 which connects to the end surface 52 of the body 14. The intermediate portion extends along at least a portion of the lengths of the outer and end surfaces 50 and 52.

[0074] In the embodiments of Figure 1 to 15, the intermediate portion 20 extends from forward ends 54 of the base portion 12 and the body 14 to a location between the forward ends 54 and the rear ends 56 of the base portion 12 and the body 14.

[0075] The end surface 52 of the body 14 of the fin 10 may include a recess 30 in which part or all of the intermediate portion is located. In the embodiments of Figures 1 to 15, such a recess 30 is provided. The recess 30 is located between the forward end 54 of the end surface 52 of the body 14 and a midpoint of the end surface 52 and receives a corresponding shoulder portion 32 extending outwardly from the second side 62 of the intermediate portion 20.

[0076] The first and second sides 60 and 62 of the intermediate portion 20 are fixed to the outer surface 50 of the base portion 12 and the end surface 52 of the body 14 respectively. In the embodiments of Figures 1 to 15, the first side 60 of the intermediate portion 20 includes a plurality of first protruding portions 64 extending outwardly therefrom. The outer surface 50 of the base portion 12 includes corresponding first apertures 65 into which the first protruding portions64 are received. The second side 62 of the intermediate portion 20 includes a plurality of second protruding portions 66 to be received in corresponding second apertures 67 in the end surface 52 of the body 14 of the fin 10. The engagement of the first and second protruding portions 64 and 66 into the corresponding first and second apertures 65 and 67 strengthens the connection of the intermediate portion 20 with the base portion 12 and the body 14.

[0077] A pin 22 is provided connecting between the base portion 12 and the body 14 of the fin 10. The pin 22 is received within aligned holes 24 provided in the base portion 12, the intermediate portion 20 and the body 14. The pin 22 is received within the body 14 such that the body 14 may rotate about a longitudinal axis of the pin 22 relative to the base portion 12. The pin 22 extends outwardly away from the base portion 12 into the body 14 of the fin 10. The pin 22 in the embodiment shown extends generally perpendicular to the lower surface of the watercraft adjacent the base portion 12. That is, the pin 22 extends perpendicular to a longitudinal axis of the base portion 12.. It will be appreciated however that slight variations in orientations may be used, such as the pin 22 being oriented at a slight angle to an axis perpendicular to the longitudinal axis of the base portion 12.

[0078] The pin 22 is located in the base portion 12 at a location between the leading edge 18 of the fin 10 and a centre of the base portion 12. In the embodiment shown in Figures 1 to 9, a lower end of the pin 22 extends down into a forwardmost of the tabs 16.

[0079] The flexibility of the intermediate portion 20 controls the amount by which the body 14 may rotate about the pin 22 relative to the base portion 12. The intermediate portion 20 is formed from a flexible and resilient material such that the body 14 of the fin 10 may pivot slightly under force, such as forces experienced during turning of the surfboard, and will then return to a central position when the force is removed such that the body 14 is in alignment with the base portion 12.

[0080] The embodiment of Figures 1 to 15 includes also a rotation limiter provided between the base portion 12 and the body 14. The rotation limiter isprovided to limit the degree to which the body 14 may rotate about the pin 22 relative to the base portion 12.

[0081] The rotation limiter in the embodiment shown comprises a rod 34 extending through aligned bores 36 passing through the intermediate portion 20 and into the body 14 and the base portion 12. The bores 36 are wider than the diameter of the rod 34 such that the body 14 of the fin 10 may pivot about the pin 22 until the rod 34 engages with edges of the bores 36. The rod 34 includes a sleeve 38 of a compressible material into which the rod 34 is received to fill the space between the rod 34 and the inner side of the bores 36.

[0082] While the embodiments of Figures 16 to 38 are not shown including a rotation limiter, it will be appreciated that such a rotation limiter may be applied to these embodiments.

[0083] Figure 11 to 15 show a second embodiment of a fin 10 in accordance with the present invention. The fin 10 of Figures 11 to 15 is similar to the previous embodiment and like reference numerals are used to denote like parts. The embodiment of Figures 11 to 15 utilises a different shape for the base portion 12 in order to engage into an alternative fin box.

[0084] Figures 16 to 21 show a third embodiment of a fin 10 in accordance with the present invention. Figures 22 to 25 show a fourth embodiment of a fin 10 in accordance with the present invention and Figures 26 to 35 show a fifth embodiment of a fin 10 in accordance with the present invention. The fins 10 of Figures 16 to 35 are similar to the previous embodiments and like reference numerals are used to denote like parts.

[0085] In the embodiments shown in Figures 16 to 25, the intermediate portion 20 extends from the trailing edge 19 of the fin 10 to the leading edge 18 along the full lengths of the outer surface 50 of the base portion 12 and the end surface 52 of the body 14.

[0086] While the material of the intermediate portion 20 may be used to vary the flexibility of the fin 10 as required, the shape of the intermediate portion 20 in other embodiments may also be varied to vary flexibility and characteristicsin use. In the embodiment of Figures 16 to 35, the intermediate portion 20 comprises a first side portion 26 located adjacent the base portion 12, a second side portion 27 located adjacent the body 14 and a connecting portion 28 extending between the first and second side portions 26 and 27. The shape of the first side portion 26 corresponds to the shape of the outer surface 50 of the base portion 12 and the shape of the second side portion 27 corresponds to the shape of the end surface 52 of the body 14.

[0087] The connecting portion 28 in the embodiment of Figures 16 to 21 is generally U-shaped in cross sections taken perpendicular to the plane of the fin 10 as can be seen in Figure 20.

[0088] In the embodiments of Figures 22 to 35, the connecting portion 28 is generally linear in cross section. In the embodiment of Figures 22 to 25, the connecting portion 28 extends from a first edge of the first side portion 26 to an opposite second edge of the second side portion 27 such that the intermediate portion 20 is generally Z-shaped in cross sections taken perpendicular to the plane of the fin 10. In the embodiment of Figures 26 to 35, the connecting portion 28 extends from a central location on the first side portion 26 to a central location on the second side portion 27 such that the intermediate portion 20 is generally l-shaped in cross section.

[0089] In the embodiment of Figures 26 to 35, the intermediate portion 20 extends from the trailing edge 19 to a location adjacent the pin 22 such that the front end of the intermediate portion 20 is offset rearwardly of the leading edge 18.

[0090] Figure 36 to 38 show a sixth embodiment of a fin 10 in accordance with the present invention. The fin 10 of Figures 36 to 38 is similar to the previous embodiments and like reference numerals are used to denote like parts.

[0091] In the embodiment of Figures 36 to 38, the intermediate portion 20 does not extend to either of the leading or trailing edges 18 or 19. The intermediate portion has a forward end located between the pin 22 and the forward edge 18 and a rear end located between the pin 22 and the trailing edge 19. Theintermediate portion 20 therefore comprises a relatively short member located only around the pin 22.

[0092] It will be readily apparent to persons skilled in the relevant arts that various modifications and improvements may be made to the foregoing embodiments, in addition to those already described, without departing from the basic inventive concepts of the present invention.

Claims

Claims1. A fin comprising: a base portion attachable to a lower surface of a watercraft; a body of the fin extending away from the base portion; a pin connecting the base portion to the body, the pin extending outwardly away from the lower surface of the watercraft; and an intermediate portion being resilient and flexible relative to the body and the base portion and extending along at least a portion of the length of the fin connecting the base portion to the body such that the body may pivot about the base portion by flexing of the intermediate portion.

2. A fin in accordance with claim 1 , wherein the pin is located between the leading edge and a centre of the base portion.

3. A fin in accordance with claim 1 or 2, wherein the pin is received in aligned holes in the base portion, the body and the intermediate portion.

4. A fin in accordance with any one of the preceding claims, wherein the pin is oriented perpendicular to a longitudinal axis of the base portion.

5. A fin in accordance with any one of the preceding claims, wherein the intermediate portion includes a first side fixed to an outer surface of the base portion and a second side fixed to an end surface of the body.

6. A fin in accordance with any one of the preceding claims, wherein a rotation limiter is provided to limit the degree to which the body may pivot about the pin relative to the base portion.

7. A fin in accordance with claim 6, wherein the rotation limiter comprises a rod received in aligned bores in the base portion, the intermediate portion and the body, located between the pin and rear ends of the base portion and the body.

8. A fin in accordance with claim 7, wherein the bores are wider than the diameter of the pin to allow movement of the body relative to the base portion and wherein a compressible sleeve is provided around the rod.

9. A fin in accordance with any one of the claims 5 to 9, wherein the first and second sides of the intermediate portion include protruding portions received in corresponding apertures in the outer surface of the base portion and the end surface of the body.

10. A fin in accordance with any one of claims 5 to 9, wherein the end surface of the body includes a recess into which a portion of the intermediate portion is received.

11. A fin in accordance with any one of the preceding claims, wherein the intermediate portion extends from adjacent a leading edge of the body to a location between the leading edge and the trailing edge of the body.

12. A fin in accordance with one of the preceding claims, wherein the intermediate portion comprises a first side portion located adjacent the base portion, a second side portion located adjacent the body and a connecting portion extending between the first and second side portions such that the shape of the first side portion corresponds to the shape of the adjacent outer surface of the base portion and the shape of the second side portion corresponds to the shape of the adjacent end surface of the body.

13. A fin in accordance with claim 12, wherein the connecting portion is II- shaped in cross sections taken perpendicular to the plane of the fin.

14. A fin in accordance with claim 12, wherein the connecting portion is generally linear in cross sections taken perpendicular to the plane of the fin.

15. A fin in accordance with claim 14, wherein the connecting portion extends from a first edge of the first side portion to a opposite second edge ofthe second side portion such that the intermediate portion is Z-shaped in cross sections taken perpendicular to the plane of the fin.

16. A fin in accordance with claim 14, wherein the connecting portion extends from a central location on the first side portion to a central location on the second side portion such that the intermediate portion is generally l-shaped in cross section.

Images