Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
  • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
  • B63B32/00—Water sports boards; Accessories therefor
  • B63B32/60—Board appendages, e.g. fins, hydrofoils or centre boards
  • B63B32/62—Board appendages, e.g. fins, hydrofoils or centre boards characterised by the material, e.g. laminated materials; characterised by their manufacturing process

Definitions

• This invention relates to improvements to part of or parts associated with a waterborne craft, in particular but not exclusively to one or more of the fins associated with a surf or sail board, that are either mountable to or are integral with the board.
• keel or centreboard on a marine vessel such as a boat counteracted the problem of unwanted leeward motion of the vessel and also assisted in its stability.
• Other types of fin fitted to other types of waterborne craft tend to serve similar purposes but in addition, may also be targeted towards solving or counteracting other problems that the craft experiences in the water.
• the traditional long board with a fixed large "keel" fin located towards one end along the longitudinal axis of the board has to all intents and purposes, been replaced by a shorter surfboard and a fixed three fin configuration.
• the keel fin has become smaller with two 'mirror image', cambered lateral fins being located on either side of the board's longitudinal axis and near to the edge of the board. Shaped like an aircraft wing in cross section with a high pressure substantially planar surface on one side and a low pressure curved surface on the other, these lateral or side fins once fitted to the board, point towards the longitudinal axis of the board and are substantially equidistant from the keel fin.
• FIG. 1 is a stylised view of the underside of a conventional three fin surfboard and water flow across one of the lateral fins.
• cavitation a well known phenomenon that is the sudden formation and collapse of low-pressure bubbles in liquids by means of mechanical forces (for example those resulting from the rotation of a marine propeller).
• Ventilation occurs when a fin is out of the water momentarily (which often occurs during surfing and especially on turning) and a large a amount of surface air is violently 'sucked 5 down the low pressure side of the fin in substantially the direction of the longitudinal axis of the fin, interrupting attached water flow causing it to 'detach' and as a consequence, causing spin out to occur.
• a keel, fin, or centreboard for use with a waterborne craft comprising a first portion operatively linked to a second portion wherein the first portion is adapted to move relative to the second portion and wherein the keel, fin, or centreboard is provided with a stop member to prevent unwanted movement of the first portion.
• first portion could be a major portion of the keel, fin or centreboard relative to the second portion (the minor portion), preferably, the first portion is a minor portion and the second portion is a major portion of the keel, fin or centreboard.
• the first or the minor portion of the fin is likely to be the only part that moves and is restricted in its relative movement, the gains made in the degree of control associated with turning tend not to be at the total expense of lost forward drive of the board.
• the movement of the first portion relative to the second portion may be a pivotal movement of the first portion with no flexing of the first portion at all or alternatively, the first portion may effectively pivot and flex or curl as it moves as a result of water pressure acting on it.
• movement of the first portion is in the form of a progressive flexing curl substantially about a leading edge of the first portion fixed point.
• the degree of "flexing curled" movement will increase.
• the stop member could form part of the overall fin but be a separate from it.
• the stop member need not be integral with the fin but could form part of it.
• the fin and stop member may each be glued onto the board separately and finished in a traditional manner.
• the stop member may be integral with the fin and as such, could form part of the second portion or the first portion.
• the stop member forms part of the second portion, thus enabling the first portion to potentially sit, locked within the second portion to present a traditional fin to the water when unwanted movement of the first portion is desired.
• stop member for example one acting on one part of the first portion of the fin and one acting on another part of the first portion.
• the surfing community are particularly astute when it comes to what they 'feel' is going to work and what is not and the introduction of a new type of fin that does not at first sight look like a traditional fin is not going to be accepted, thus although there are several ways available to a person skilled in the art to link the second and first portions of the fin together, one that results in a fin that at least looks like a traditional fin is preferable.
• the second and first portions are provided with complementary engaging members to enable the portions to be operatively linked.
• one of the complementary engaging members is provided with a guide member. This will assist the initial location of the other engaging member onto the one bearing the guide member.
• the guide member is located on the engaging member carried by the second portion.
• the two portions may be disengaged through the action of water on the fin unless some form of locking member is used to lock the second and first portions together once they are engaged in an operatively linked manner.
• the locking member may be some form of snap fit arrangement involving complementary aspects of the second and first portions however, one of the traditional ways of locking a fin to a board is preferably through the use of complementary male and female locking members.
• the fin is provided with ⁇ complementary male and female locking members to lock the first portion to the second portion.
• the board and the fin are both provided with a female screw threaded aperture. It is envisioned that the same process could be used to lock the first and second portions of the fin to each other. More preferably, therefore, the same type of locking member is located on both the second and first portions. Thus, for example, 'female' screw threads could be found on both the second and first portions.
• the first and second fin portions may be made from the same type of material, most typically plastics material, natural rubber, carbon fibre, metal or possibly wood, however, they may be made from different materials or any appropriate selection or combination the materials mentioned herein.
• the first portion is formed from two types of plastics material. If one of the plastics materials has a lower glass transition temperature with respect to the other (to all intents and purposes, if one is 'rubbery' and one is 'hard' at their "in use” temperature), then depending on the arrangement of hard and rubbery plastics that make up the first portion, the ability of the first portion to flex may be enhanced.
• At least the leading and/or trailing edge of the first portion is formed from 'hard' plastics material. This will have the advantage that less movement along the leading edge of the first portion is possible thus enabling straight gluing of the first portion to the second portion to occur with a reduced possibility of detachment through the effects of water striking the "join".
• the trailing edge of the first portion could, in principle form the entire trailing edge of the fin once the fin has been formed. It could form only a percentage of the total trailing edge of the fin and in certain instances, there may be occasions where none of the trailing edge of the fin is formed from the first portion.
• the first portion sits wholly within the second portion once both portions are operatively linked to form the fin.
• the fin could be a keel, however the fin is preferably a lateral fin.
• the first portion could form part of the leading edge of the fin and/or the trailing edge of the fin.
• the trailing edge of the first portion could form part of the trailing edge of the fin when it is operatively connected to the second portion however this need not necessarily be the case.
• the first portion could sit within an aperture of the second portion, the trailing edge of the second portion forming part of the wall of the aperture.
• the trailing edge of the first portion forms part of the trailing edge of the fin, once it has been operatively connected to the second portion.
• the first portion only forms part of the trailing edge of the fin.
• the waterborne craft may be selected from the group comprising a dinghy, yacht powerboat, sailboard and surfboard.
• the keel, fin or centreboard is provided with a stop member to prevent unwanted movement of the first portion and wherein the fin is also provided with apertured ducting to enable a fluid to enter the ducting and exit through one or more of the apertures and over a portion of one side of the fin.
• the ducting is located internally to the fin thus enabling the fin to keep its traditional shape.
• the or each exit aperture of the ducting may overlie the second or the first portion of the fin, however preferably, the or each exit aperture overlies the major portion of the fin. Such an arrangement will allow all of the first portion of the fin to move, relative to the second portion.
• the fin could be a keel, however the fin is preferably a lateral fin.
• a keel, fin, or centreboard for use with a waterborne craft, wherein the keel, fin or centreboard is also provided with apertured ducting to enable a fluid to enter the ducting and exit through one or more of the apertures and over a portion of one side of the keel, fin or centreboard.
• the fin could be a keel, however the fin is preferably a lateral fin.
• the fluid may be a liquid supplied in a container that is mountable to the board, the liquid having properties that may help to re-establish the Coanda effect or alter the degree of surface tension that exists between the water and the fin.
• the liquid could either reduce or increase the surface tension adjacent the fin surface.
• the fluid is air.
• This air is 'sucked' down the ducting and expelled across the low pressure side of the fin in a controlled or otherwise metered fashion and in a direction substantially transverse to the longitudinal axis of the fin.
• the nature of the surface of the fin may be substantially hydrophobic or substantially hydrophilic, in the alternative, one side of the fin may possess a hydrophobic surface whilst the other may be hydrophilic.
• the invention includes within its scope a waterborne craft incorporating a keel fin or centre board as specified herein.
• Figure 1 illustrates an underside view of three surfboards showing their fin arrangement and a stylised view of water flow about each leading lateral fin, one of the boards being a prior art board and the two others being differing embodiments of the present invention.
• Figure 2 illustrates a side view of one embodiment of the present invention showing a lateral in comprising a second portion being fitted with a flexible first portion, that is flexible in one direction only.
• Figure 3 illustrates an isometric exploded view of a lateral fin covering a second embodiment of the present invention.
• Figure 4 illustrates an isometric exploded view of a lateral fin covering a third embodiment of the present invention.
• Figure 5 illustrates an isometric exploded view of a lateral fin covering a fourth embodiment of the present invention.
• Figure 6 illustrates an isometric view of a lateral fin in a flexed position covering a fifth embodiment of the present invention.
• Figure 7 illustrates a cross sectional view of a lateral fin covering a sixth embodiment of the present invention.
• Figure 8 illustrates a cross sectional view of the fin shown in figure 7 fitted to an underside of a surfboard.
• Figure 9 illustrates a cross sectional view of a lateral fin covering a seventh embodiment of the present invention.
• Figure 10 illustrates an isometric exploded view of a lateral fin covering an eighth embodiment of the present invention.
• Figure 11 illustrates an isometric exploded view of a lateral, fin covering a ninth embodiment of the present invention.
• Figure 12 illustrates an isometric view of a lateral fin in a flexed position covering a tenth embodiment of the present invention.
• Figure 13 illustrates an isometric view of a lateral fin in a flexed position covering an eleventh embodiment of the present invention.
• Figure 14 illustrates an isometric view of a lateral fin in a flexed position covering a twelfth embodiment of the present invention.
• Figure 15 illustrates an isometric view of a similar embodiment to that illustrated in figure 2 except that the stop member in this particular embodiment is an integral part of the major portion and the peg is missing.
• Figure 16 illustrates an isometric view of another embodiment of a lateral fin where a trailing edge of a first portion of the fin does not form part of the trailing edge of the assembled fin.
• Figure 17 illustrates a variant of the embodiment illustrated in figure 16.
• Figure 18 illustrates in cross section, yet another embodiment of a lateral fin of the present invention.
• Figure 19 illustrates an isometric view of a flexing embodiment, similar to the embodiment of figure 10 but also showing different types of minor fin portion highlighted by differing colour tones to illustrate differing arrangements of types of plastics materials used to make up a first portion.
• Figure 20 illustrates in isometric exploded view, an embodiment of a lateral fin similar to that shown in figure 4 but encompassing different types of first portion somewhat akin to those illustrated in figure 19.
• Figure 21- illustrates a variant of the lateral fin illustrated in figure 20, fully assembled with one of the first portions glued into place and flexing.
• Figure 22 illustrates stylised water flow across three types of one of the lateral fins of the present invention when it is attached to a surfboard.
• Figure 23 illustrates an isometric view of another variant of an integral lateral fin.
• Figure 24 illustrates a front view of a variant similar to the one illustrated in figure 23.
• FIG 2 shows a polymeric integral curved lateral fin formed from polypropylene material and natural rubber and is generally referenced (1).
• the fin (1) comprises a major portion (2) a minor portion (3) and a bevelled stop member (4).
• the fin (1) is also provided with a flat base (15) and an integral columnar peg (10) located towards a convex leading edge (14) of the fin (1) which projects orthogonally from the base (15).
• the face of the fin (1) that is convex, whilst the opposing face is substantially planar.
• leading edge (14) Opposite the leading edge (14) is a somewhat similarly curved trailing edge (8, 9), which at its apex forms the base of another trailing edge of a nature of curvature (17) that is different to that of the trailing edge (8, 9).
• the trailing edge (8, 9) of the major portion (2) is provided with a 'dovetail" shaped projection (8) that extends from the base (15) of the major portion (2) along approximately 80% of the central length of the trailing edge (8, 9) of the major portion (2) and the projection (8) uniformally decreases in size as it extends linearly along from the base (15) along the length of the trailing edge (8, 9).
• the projection (8) does not project centrally from the trailing edge (8, 9) but is offset towards the flat side of the major portion (3).
• a threaded well (6) that is located towards the base (15) extends at an angle into both a portion of the projection (8) and its associated corresponding recess or non projecting portion (9) of the trailing edge (8, 9).
• the minor portion (3) is also provided with a leading edge (16) and a trailing edge (18).
• the nature of the curvature of the trailing edge (18) is similar to the nature of the curvature of trailing edge (17).
• the leading edge (16) of the minor portion (3) of the fin (1) is provided with a complementary or female "dovetail" to that of the major portion (2) and is also provided with a similarly threaded aperture (5) to that of the well (6) and the aperture (5) is also located towards the base (15).
• the base (15) of the minor portion (3) is also provided with a complementary bevel (13) of similar shape and dimensions to that of the stop member (4).
• the minor portion (3) is provided with a shaped core of natural rubber (11) that is integral with a peripheral high molecular weight polypropylene material (12) that extends from the base (15) /start of the leading edge (16) and surrounds the core (11) of the minor portion (3) of the fin (1) in a non-uniform manner, terminating at the base (15) /start of the trailing edge (18) of the minor portion (3).
• the base (15) of the major portion (2) will be provided with a layer of glue as too will the peg (10). Then the peg (10) will be pushed into a complementary well or aperture located in a lateral fin position in a surf or sail board (not illustrated) until the base (15) contacts the underside surface of the board.
• the base (15) of the stop member (4) will then be glued onto the board such that its bevelled surface contacts the complementary bevelled surface (13) of the minor portion (3).
• a grub screw (7) provided with a complementary thread to that of the aperture (5) and well (6) is screwed into both aperture (5) and well (6) locking the major portion (2) to the minor portion (3) to form the fin (1).
• fin (1) is a lateral fin for a surf board, a similar "mirror image" fin of fin (1) will be produced for the other lateral fin.
• the minor portion (3) is able to progressively flex away from the curved surface (as its , thickness diminishes) and towards the opposing flat surface but is prevented from doing so in the opposite direction by the stop member (4).
• FIG 3 shows another embodiment of the present invention where the stop member (34) is integral with the major portion (32) of the integral lateral fin generally referenced (31) and where the stop member (34) bevel extends across substantially the entire length of the internal base face of the major portion (32).
• the major portion (32) there are a pair of spaced apart pegs (310) located on the exterior base (315) of the major portion (32) adapted to mate with corresponding wells located in the board (not illustrated).
• the leading edge (33) of the minor portion (33) of the fin (31) operatively connects to the major portion (32) via the dovetail (38) in a similar manner to that described for the previous embodiment.
• FIG 4 shows a lateral fin generally referenced (41).
• the view shown for the first time clearly shows what is present in each of the fins described herein, the substantially flat surface of one side of the fin (41) and the curved opposing surface.
• Figure 5 shows another variant somewhat akin to the first embodiment but without a peg and having a boxtail instead of a dovetail.
• Figure 6 shows another variant and is generally referenced (61).
• This embodiment also shows the minor portions of the fin (61) in a flexed position revealing an instance of a stop member (64) extending along both a respective top and bottom edge of (in this case) a portion of the major portion (62).
• figure 7 shows another embodiment of the present invention and shows a lateral fin in cross section that is generally referenced (70).
• the fin (70) is similar in many regards to the others described herein in so far as it comprises a major portion (72) with an integral stop member (74) and a minor portion (73) operatively linked together via a pair of complementary dovetails and an integral peg (710) located on the planar base (715) towards the leading edge of the major portion (712).
• the peg (710) is hollow and forms part of a conduit (720) of substantially uniform cross section that extends into the body of the major portion (72) following the curve of the leading edge (714) and terminating just below the top of the minor portion (73).
• a conduit (720) of substantially uniform cross section that extends into the body of the major portion (72) following the curve of the leading edge (714) and terminating just below the top of the minor portion (73).
• Equally spaced along the trailing side of the conduit (720) are four substantially circular apertures (721) that between them span substantially the length of the minor portion (73).
• Each aperture (721) opens out onto the flat face of the fin (70) and in each case, the aperture (721) is located at one end of a recessed ellipse (722), the diameter of the aperture (721) being concentric with the longitudinal axis of the ellipse (721) of which it forms a part, the said longitudinal axis being substantially parallel with the base (715).
• Each ellipse (722) is of a similar size and shape.
• the non aperture containing end of the ellipse (722) extends across the face of the fin (70) but terminates well before the leading edge (716) of the minor portion (73).
• Figure 8 shows figure 7 mounted to the underside of a sail board (830), again all in cross section.
• the peg (710) is so sized and shaped as to extend part the way through the thickness of the board (830), the top surface of the board (830) in its normal attitude of operation being fitted with a curved non resilient cap that overlies the aperture in the board (830) through which the peg (710) enters.
• this stream of air bubbles disrupts the turbulence generated across this face during turns and helps to re-establish the Coanda effect, although the water that would normally be "sticking" to the fin (70), will not be, however, its path of travel, it is believed will be closer to it thus reducing the instances of ventilation and spin out.
• Figure 9 shows a variant of figure 7 and in this embodiment, the location of the peg (910), conduit (920), apertures (921) and ellipses (922) have simply taken a side ways shift away from the leading edge (914) of the major portion (92) to the extent that the apertures (921) and ellipses (922) are now located slightly rearward of the leading edge (916) of and now form part of the flat face of the minor portion (93).
• the trailing side of the conduit (920) is provided with minor branches (940) that extend through the male dovetail of major portion (92) and terminate in four apertures each of which overlie respective apertures (921) once the portions (92, 93) have been operatively connected.
• figure 10 this shows a lateral fin generally referenced (100) and simply shows a further variant of figure 7 with eight apertures (1021) that span the entire length of the minor portion (103).
• Figure 11 shows a lateral fin generally referenced (111) effectively shows the embodiment previously described in figure 3 except in this particular embodiment pegs (310) are missing and apertures as described in figure 7 are incorporated.
• the aperture of the board would have to overlie at least partially, the conduit of the fin in this particular embodiment as the fin has no peg to speak of.
• Figure 12 shows an embodiment incorporating apertures located on the major portion and showing the minor portion flexing.
• Figure 13 shows an embodiment incorporating apertures located on the minor portion and showing the minor portion flexing.
• Figure 14 shows a variant of the embodiment described in figure 6 incorporating apertures on the major portion and showing both minor portions flexing.
• Figure 15 shows an isometric view of a similar embodiment to that illustrated in figure 2 except that the stop member (154) in this particular embodiment is an integral part of the major portion (152) and the peg (10) of figure 2 is missing in this particular embodiment allowing the base (1515) to be fixed in the traditional manner to a surf board (not illustrated).
• Figure 16 shows an isometric view of another embodiment of a lateral fin generally referenced (161) where a trailing edge of the minor portion (1618) of the fin (161) does not form part of the trailing edge of the assembled fin (161). In essence, the minor portion (1618) is housed within an aperture of the fin (161).
• Figure 17 shows an alternative embodiment to that shown in figure 16 essentially from the other side, highlighting the single stop member (174) that runs continuously and substantially uniformally along three sides of the major portion (172).
• Figure 18 shows in cross section a variant of the embodiment shown in figure 7.
• the fin is a single fin with no major or minor portion but possesses the ducting and air holes that the inventor believes also tend to reduce the turbulence associated with high speed turns, thus tending to prevent the phenomenon of known as spin out.
• Figure 19 shows an isometric view of a flexing embodiment (with the minor portion (193) flexing at its unsecured end), similar to the embodiment of figure 10 but also showing different types of minor portion (193) highlighted by differing colour tones to illustrate differing integral arrangements of types of flexible and relatively non flexible plastics materials used to make up the minor portion (193).
• Figure 20 shows in isometric exploded view, an embodiment of a lateral fin similar to that shown in figure 4 but encompassing different types of minor portion somewhat akin to those illustrated in figure 19.
• Figure 21 shows a variant of the lateral fin illustrated in figure 20, fully assembled with one of the minor portions glued into place and flexing, together with other types of minor portion comprising different types of plastics material of the type described herein.
• Figure 22 shows an underside view of three surfboards showing their fin arrangement and a stylised view of water flow about one of the lateral fins.
• Each board show the expected water flow with three different embodiment types, the first (uppermost) shows a flexible minor portion moving, the second (middle) shows a non flexible air hole variant and the third (lowermost) shows a combined air hole/minor portion moving variant.
• Figure 23 shows an integral lateral fin generally referenced (230) formed from two types of plasties polymer, the relatively hard polypropylene and a relatively soft silicone co-polymer. Whilst some of the figures e.g. 2, 3, 4, 5 & 11 are integrally assembled, some others e.g. 6, 23 & 24 are integrally formed.
• the first portion formed from the silicone co-polymer (the one that is designed to flex) (232) is integral with the rest of (or the second portion (235)) of the fin (230) in a substantially continuous substantially curved "V" shaped manner along both the leading and trailing edges of the first portion (232).
• the base of the "V” forms the apex of the first portion (232), the first portion to all intents and purposes being housed within the confines of the arms and base of the "V”.
• This arrangement provides the first portion (232) with some structural rigidity as the trailing edge of the fin (230) is formed from the polypropylene polymer and the leading edge of this trailing edge is integral with the trailing edge of the first portion (232).
• the trailing edge of the fin (230) slightly and gradually increases its dimensions as one moves from the base of the "V” along the trailing edge arm of the "V” towards the stop member (234) and the base of the first portion (232).
• the base of the first portion (232) together with that portion of the trailing edge of the fin (230) that is flush with the base of the first portion (232) are both free to flex relative to the rest of the fin (230) in one direction only thanks to the stop member (234).
• the degree of flexing available to the first portion (232) will become greater as one moves from the apex of the first portion (232) ⁇ in other words the base of the "V" ⁇ and towards the stop member (234). Furthermore, as only the base of the first portion (232) is completely free to move relative to the rest of the fin (230), it will be appreciated that the degree of flex available at the apex of the first portion (232) is not going to be the same as other embodiments where both the base and apex of theses equivalent portions are both completely free to flex.
• FIG. 24 that is generally referenced (240), this is similar to the fin (230), however the overall shape of the fin in this particular embodiment is slightly different. It is to be appreciated that in all of the embodiments herein described, a lateral fin is shown, the majority with a minor and major portion, for Hie avoidance of doubt and to all intents and purposes the invention is also intended to include within its scope the minor portion of any one embodiment (with llie appropriate redesign) being fitted to a major portion of any other embodiment. It is to be appreciated that the invention could be applied to a keel fin or centre or dagger board.
• This invention may broadly be said to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of the parts, elements or features, and where specific integers are mentioned herein, which have known equivalents, such equivalents are deemed to be incorporated herein as individually set forth.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Toys (AREA)
• Nozzles For Electric Vacuum Cleaners (AREA)

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• 2005
  • 2005-06-13 NZ NZ540706A patent/NZ540706A/en not_active IP Right Cessation
• 2006
  • 2006-06-07 JP JP2008515647A patent/JP5155158B2/ja not_active Expired - Fee Related
  • 2006-06-07 WO PCT/NZ2006/000140 patent/WO2006135256A1/en not_active Ceased
  • 2006-06-07 AU AU2006258322A patent/AU2006258322B2/en not_active Ceased
  • 2006-06-07 US US11/917,259 patent/US7896718B2/en not_active Expired - Fee Related
  • 2006-06-07 EP EP06769464A patent/EP1890931A4/en not_active Withdrawn
• 2007
  • 2007-12-13 ZA ZA200710831A patent/ZA200710831B/xx unknown

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