GB2451237A - A foldable boat hull structure - Google Patents

Abstract

A pre-fabricated folding structure, in particular a folding boat hull 13, comprises a plurality of profiled panel segments (19, 20, 24, Fig 1B), with juxtaposed edges, conjoined by resilient hinges 37, 38 profiled as continuous edge seals. The structure is configured for overall collapse fold conversion between a 3-D erect state (12, Fig 3A) and a compact stacked flat-pack state (10, Fig 1A). Transverse end seats (46, 47, Fig 5A) at stern and bow may be provided to preserve an erect form and are secured by snap-action, over-centre fasteners (60, Fig 5C). Permanent pliable fabric end wall panels (22, 21, Fig 4A) may be provided at stern and bow and preserve overall flotation and may be buttressed by demountable end wall panels 50 and 54. Storage of ancillary components may be provided in partially-closed internal compartments defined between corresponding facing panels (20, Fig 1B) in-folded about a base panel (19, Fig 1B).

Description

Folding Structure -Boat Hull This invention relates to folding segmented or fragmentary structures, such as folding shells or hulls for small boats, whether dinghies or sail craft Rather than a loose collection of disparate parts, liable to mis- assembly or loss, one consideration is mutual entrainment of sub-component elements in a unitary collapse-fold module. This would allow a unique, even fail-safe, default assembly mode Aside from correct assembly, such as through a prescribed assembly sequence, ensuring that all fasteners are secured, is desirable, so visibility of fastener disposition is helpful to that end.

In a prime water craft vehicle' implementation, a compact format, light-weight, collapse-fold boat hull of synthetic plastics materials is envisaged for ease of handling, transport and storage. This requires resolution of a myriad of fabrication, construction and assembly detail for a fail-safe, waterproof performance.

An objective is realisation of quasi-curved' or progressive in-turned polygonal 3-D erect forms, from individually flat or largely flat element forms by mutual outward folding, allowing relative juxtaposition of elements in a segmented path following an approximating to a curve This allows some attention to hull form drag in passage through the water, buoyancy by displacement, handling, manoeuvrability and stability

Prior Art

Folding wooden boats are known, such as per GB2023586, but are structurally more complex in fabrication (so generally not lending themselves to mass production) and vulnerable to deterioration by weathering. Inherent expansion and contraction of material with moisture and temperature is greater and less predictable than with synthetic plastics Thus preservation of relative inter fit and water-tight assembled hull forms is more challenging, as is inter-component hinge design.

Water-tight joints between panels are critical for flotation and buoyancy.

Regular ongoing maintenance and storage in a benign dry environment is desirable Thin-wall lightweight (aluminium or alloy) metal designs, such as INSTABOAT(www.instaboat.com), have also been devised, but are vulnerable to denting and expensive to produce.

A largely or wholly synthetic plastics material, in particular glass fibre with a gel coat surface finish over filler layer, offers greater weather-resistance and general durability in handling than a timber structure, albeit at a greater weight penalty, with less inherent buoyancy. Thus glass fibre has become a dominant construction media for rigid hull boats of all sizes, particularly small dingies Although gel coat hygroscopic issues remain, such construction has proved generally durable and sustainable.

A particular challenge is to achieve a compliant or conformal hinge which will adapt to a target assembled hull form, yet provide a permanent water-tight seal through its range of hinge articulation, flex or fold. In that regard, tapered panel profiles and/or shallow curved panel forms provide a challenge, as does, conversely, achieving a curved form from a series of interconnected flat panels 1/20 Hinges designed for timber folding hull construction do not necessarily perform satisfactorily for plastics materials, or rather plastics material offer opportunities for improved hinge design attendant greater inherent panel material homogeneity, integrity and stability Glass fibre offers opportunities for more complex continuous profiles, surface contours and 3-D forms along with integrally moulded local section variation, such as for stiffener or bracing ribs, and fastener mountings.

Higher performance esoteric fibre reinforced materials, such as carbon fibre or keviar reinforced composites, might be used locally where high performance and low weight are at issue Glass fibre is a lower cost material, but heavier for a given structural strength and its strength less readily determined. Laminated timber such as marine ply also offers strength, but is less readily tailored by machining or forming than, say, a laid-up moulding.

Conventional Rigid Hull A conventional fixed format rigid hull is bulky, intrusive, awkward profile and heavy for handling, transport and storage, even for small dingies Thus a hull shell might commonly be inverted (to avoid rainwater collection) for open storage, or covered with a tarpaulin for some weather protection. Such a rigid form is easier to fabricate or mould and indeed to keep water-tight, but is inflexible Collapse-Fold Rationale A prime rationale for a folding hull includes compact handling, transport and storage, as compared with a fixed format or rigid hull of equivalent size. A challenge is to preserve water handling and buoyancy An erected hull size to achieve full displacement is preserved with a collapse-folded profile of similar longitudinal span (that is for a longitudinal folding version), but a narrow internal span reflecting cumulative stacked panel depths. Removable end wall panels are fitted to brace and stiffen fabric end walls contiguous with or joined by waterproof seams to the sidewall panels. The sidewalls and fabric end walls thus form a flexible waterproof assembly, into which cross-bracing is fitted for a stiffened erect hull form.

Primary cross-bracing or stiffening elements are the end walls including a stern transom or cross-member with a top edge recess or cut-out for possible outboard engine mounting, a mid-brace and transverse bow and stern end seats, with intermediate longitudinal side seats fitted there between. An upstanding keel carrier yoke is integrated with a narrow mid hull bottom panel. A mast mounting upstanding pedestal collar is fitted forward of that.

A demountable tiller can also be fitted to the stern transom

Statement of Invention

A collapse-fold 2-D flat panel assembly is configured to form a prefabricated 3-D structure when erect, with intervening resilient panel hinges between juxtaposed panel edges, to accommodate a complex contour 3-D erect form.

One such structure is configured as a boat hull, subdivided (longitudinally) into a plurality of discrete, but pliably interconnected, (panel) sections with intervening resilient seals 2/20 A flex(ible) hinge between panel sections and with hinge limbs (sealingly) engaging panel edges, is an example. Hinge demands are both mechanical, in keeping components in relative juxtaposition, yet allowing their movement for collapse fold and erection along with preserving a water tight intervening seal A pre-profiled panel section for a boat hull with a resilient, flexible or compliant hinge element filled along one or more peripheral edges for co-operative coupling to, and folding interaction with, another such panel A chopped fibre strand reinforcement embedded in a plastic resin bonding agent with a bulking agent or filler, such as a glass fibre composite, would be a prospective material, with a foam embedded and resin bonded between outer skin sandwich construction for stiffness without undue weight penalty. An outer protective outer barrier finish gel coat, acrylic clear seal and/or (colour) paint might be applied in a desired colour and as relatively impermeable UV light resistant barrier layer Minor gel coat porosity can be filled by a paint covering layer.

Panel Edge Interconnection A plurality of edge interconnected panels can be deployed around a former, constraint or guide, to follow a segmented polygonal or approximate curved hull form.

Repeat Panel Folding A degree of repeat folding, such as over-folding, is envisaged for a compact overall form, with inner leaves tucked within or sandwiched between outer leaves, offering some protection and a stiffer overall form for handling and storage.

Base Mid-Panel For symmetry of disposition, it is convenient if such folding takes place about a mid-panel, such as one which serves as a ground base, and thus upon which the folded assembly can be rested, with corresponding side fold on each side The folded over sides could cant slightly inwardly together or an intervening bridge or prop, or rest upright, with an intervening elongate longitudinal storage slot or channel in between.

Panel Flex A certain modest panel bend or flex from a generally flat default planar format can be used to follow a somewhat more curved form, by drawing mutually-entrained panels against a profiled former, such as an end wall and between differentially-sized panels at each end, to achieve a waisted contour, such as for a boat hull.

Flex Joint -Hinge A flex joint or hinge could be fitted between panels to accommodate panel shape and shape adjustment. A continuous such pane edge joint could provide local bridging surface continuity for a contiguous segmented form. A modest inherent hinge stiffness could impart some behavioural discipline to a panel assembly -that is inhibit what might otherwise be a disconcerting looseness, floppiness or uncertainty of form. Assembly rigidity can also be achieved by inter-fastening and cross-bracing of panel elements 3/20 Slatted Panels Multiple entrained slatted panels are known from such structures as roller shutter doors, as is some form or intervening draft or weather strip or seal, but these are generally not intended as water-tight under immersion An objective is a water-tight joint without resorting to a continuous membrane overlay.

Embodiments Figures 1 A to 1 B show a segmented collapse-fold boat hull of fibreglass component membrane segments or sections, juxtaposed with intervening flexible rubber hinge joints; More specifically.

Figure 1A shows a folded in boat hull,with hull sides tucked-in and hull side base panels folded up. bow and stern membrane covers collapse fold at each end; Figure lB shows an opened out boat hull, hull side base panels are laid flat, and hull sides are folded out leaving a central stand column upstand; Figures 2A to 2E show close up cross-sectional detail of H' Jointing pieces, bow membrane cover and fibreglass composition; More specifically Figure 2A shows a cross-sectional view across a hinge joint between a hull centre base panel and a hull side base panel (x-x' as shown in Figure 1B) Figure 2B shows a cross-section view as in Figure 2A with the hinge joint laid open Figure 2C shows a cross-sectional view of stern membrane cover, secured and sealed against the hull centre base panel by sealed edging.

(w-w' as shown in Figure 1B); Figure 2D shows a cross sectional view of a fibreglass panel, revealing a foam core or fillet sandwiched between outer fibreglass layers (z-z' as show in in Figure 1D); Figure 2E shows a cross sectional view across a hinge joint between a hull side base panel and a folded flat hull side panel. (y-y' as shown in Figure 1B); Figures 3A to 3B show a opened out boat hull, a central thwart and cross-sectional detail of side panels; More specifically...

Figure 3A shows a fully open boat hull, revealing internal details including, rubber grip deck flooring, thwart supports on internal surface of hull side panels, and inside top rail reinforcement; Figure 3B shows an enlarged cross sectional view of a rail, on a hull side panel (u-u' as show in Figure 3A) 4/20 Figures 4A to 4C show further constructional detail as the central thwart is secured in place and transom and bow plates are manoeuvred into place; More specifically...

Figure 4A shows a fully open boat hull, with central thwart fixed in place by a fastener, transom and bow plates are lined up at the stern and bow respectively Figure 4B shows the underside of the central thwart and juxtaposition of a rotation toggle with an aperture within the central stand column Figure 4C shows the underside of the central thwart, with toggle arms engaged with an aperture within the central stand column.

Figures 5A to 5C show further constructional detail, as front and stern thwarts are mounted and secured in place; More specifically...

Figure 5A shows a hull assembly of Figure 4A with front and stern thwarts or seats lined up for assembly. Transom and Bow plates are secured to the hull side panels by fastener clasps; Figure 5B shows a partially assembled boat hull, front and stern thwarts are in position upon supports embedded in hull side panels, and are secured by fastener clasps; Figure 5C shows and enlarged cross sectional view of a transom plate with a folded top edge fitted over the top edge of the stern membrane cover, and a lip ledge supporting the stern thwart A hinged clasp lever fastener is shown securing the transom to the the hull side panel (v-v' as show in in Figure 5B) Figures 6Ato 6B show further constructional detail; More specifically.

Figure 6A shows a side seat with T-end lined up for nesting within matching profiled recesses within the central and stern thwarts; Figure 6B shows a side seats in place, securing dowelling, ties or secures can be added; Figures 7A to 7C shows buoyancy configurations; More specifically.

Figures 7A shows an buoyancy in place under the stern thwart and insert lateral buoyancy under the central thwart along the length of the hull; Figure 7B shows use of securing straps with a fastener to keep inflated buoyancy in place; Figure 7C shows deployment of external buoyancy edges of the boat hull, potential modular composition of a lateral buoyancy is indicated; 5/20 Figures 8Ato 8B shows insertion of a dagger or centre board through the central stand column and addition of a rudder; More specifically Figure 8A shows a dagger board lined up with an aperture slit in the central stand column, and a rudder juxtaposed with the transom plate; Figure 8B shows the dagger board inserted through the centre board and protruding below the hull base and a rudder affixed to the transom plate; Figures 9A to 9C show a sailing boat variant; More specifically Figure 9A shows a folding hull sail boat, with two sails, mast, boom and rigging Figure 9B shows a folding hull sail boat with a main sail and a jib sail with bowsprit and forestays; Figure 9C shows a folded boat with a collapse-fold mast and folded sails; Figure 10 shows a folding hull boat with row-locks and oars; Figure 11 shows a folding hull boat fitted with an outboard motor; Figures 12A to 12 B show a folding boat fitted with an automatic self-bailer device; More specifically...

Figure 12A shows a folding boat hull, fitted with an automatic bailer, within a central hull base panel; Figure 12B shows an enlarged view of the automatic bailer; Figure 13 shows the underside of a folding boat hull, whereby the underside of the automatic bailer, transom plate skirt, fastener between transom plate and hull centre base panel and a skeg wheel can be seen; Figures 14A to 14C show all individual component parts and a potential stowage scheme; More specifically...

Figure 14A shows component pieces including rudder, thwarts, dagger board, seating, buoyancy, transom and bow plates laid out into groups with straps to form three compact clusters or bundles; Figure 14B shows insertion of component bundles into the internal cavity of a folded in boat hull; Figure 14C shows a folded-in boat with component bundles stored inside; Figures 1 5A to 1 5B show a holdall bag and tube bag for storage of the folded boat hull and sailing apparatus; 6/20 More specifically Figure 15B shows a holdall bag containing a folded boat hull and a separate tube bag containing, sails, masts, booms, and rigging; Figure 15B shows a tube bag fastened to a holdall bag; Figures 1 6A to 1 6D show various covers for folding boat; More specifically.

Figure 16A shows a folding boat with a pitched tent canopy cover; Figure 16B shows a folding boat with a flat cover; Figure 16C shows a folding boat with a half cover, deployed over the boat prow; Figure 16D shows a boat cover of Figures 16B being used as a sling for transportation of the folded boat hull; Figures 1 7A to 1 7C depict, storage of component parts within pockets of a boat cover designed to fit inside the folded boat hull; More specifically..

Figure 1 7A shows a boat canopy or cover with pocket compartments and straps for collective storage of individual component pieces; Figure 1 7B shows a boat canopy of Figurel 7A folded for storage inside the folded-in boat hull.

Figure 17C shows a folded boat hull with straps for fastening component pieces; Figure 17D shows a folded boat hull secured with straps and having handles to assist in transportation; Figures 18A to 18C show alternative hull conformations; More specifically..

Figure 18A shows a folding dingy; Figure 18B shows a folding kayak; Figure 18C shows a folding twin hull catamaran with a single deck spanning both hulls; Figures 19A to 19B show a folding hull capable of being split longitudinally into discrete fore and aft hull sections, about a transverse beam axis, at or around about mid-span; each section could be configured for self-flotation by fitting respective fabric or solid end walls More specifically...

Figure 19A shows a perspective view of a hull split into discrete fore and aft hull sections, with a residual mid-section seat set upon a keel upstand on an aft hull portion; 7/20 Figure 19B shows a split hull of Figure 19A, with discrete fore and aft hull sections inter-connected by fasteners with optional additional cross seating depicted in broken outline; Figures 20A to 20B show further canopy configurations; More specifically...

Figure 20A shows a folded boat hull with a partial tonneau cover at the forward (bow), leaving open seating room for partial occupancy at the other (stern) end; Figure 20B shows a folded boat hull with an raised overall canopy cover carried on corner support stakes at the hull corners; Figure 21 shows a boat hull with one or more under-seat storage compartments; Figure 22A through 22C show collapse-folding prefabricated building structures, reflecting the construction and operation of the folding hull disclosed in Figures 1 through 21; More specifically.

Figure 22A shows an underside perspective view of a collapse-folding building shell, superficially resembling an upturned boat hull, with modestly bowed panels surmounted by a pitched roof; Figure 22B shows a variant folding building shell with flat wall and roof panels; Figure 22C shows a modular building format, of two folding building structures juxtaposed end-end; Figure 23 shows a collapse folding coffin, with lid; Figures 24A to 24B show a hull and folding panel construction and interaction in more detail, through a local longitudinal sectioning; of a stern section; More specifically...

Figure 24A shows a perspective view of a boat hull with section line delineation t-t; Figure 24B shows a longitudinal cross-section taken along line t-t' of Figure 24A; Figures 25A to 25B how a hull and folding panel construction and interaction in more detail, through a local transverse sectioning; of a stern section; this supplements the corresponding longitudinal section of Figures 24A and 24B; More specifically Figure 25A shows a perspective view of a boat hull with section line delineation s-s'; Figure 25B shows a transverse cross- section taken along line s-s' of Figure 24A; 8/20 Figure 26 shows a cross-sectional view of a 3 arm version of a hinge of Figure 2B, and joins 3 panel sections about a flexible central spine section, to allow the panels to be folded together or apart; Figure 27 shows cross-sectional view of a further hinge embodiment of Figure 2C, interconnecting four hinge panels and showing variant hinge cup profiles

Description of drawings

Referring to the drawings, a collapsible folding boat hull 15 features a series of mutually coupled or entrained complementary profiled panel sections 19, 20, 24 with intervening resilient or flexible (flex) hinges 31 At each side of the hull centre base panel 19 are mounted lower side sill panels 24 upon which in turn are mounted upper side sill panels 20. The overall side assembly represents a concertina fold array with an upper side sill panel 20 able to fold over a lower side sill panel 24 and that over- folded assembly able to fold about the base mid-panel 19 The over-folded assemblies on each side of the base mid panel 19 can thus be brought up together in juxtaposition, as depicted in Figure 1 A The fabric end walls 21,22 simple collapse fold in a sympathetic manner with some projection inward between the folded panels and some projection outward. A slim spine section of a flexible hinge 37 allow panels 20 24 mutually to overly one another, as reflected in local enlargement detail Figure 2E This is particularly advantages given the depth of a foam 33 sandwich panel as depicted in enlarged local sectional detail of Figure 2D.

The upper end of the keel guide upstand 25 features a pronounced peripheral rim, lip or upstand to help positively locate a mid-transverse seat panel 40 which carries snap-action, over-centre clip fasteners 65. A rotating toggle 45 on the seat panel 40 and aperture 27 in the keel guide upstand 25 lock the juxtaposed elements securely together, as depicted in local enlargement detail of Figures 4B and 4C.

Having folded out the side panels 20, 24 about the base mid panel 19, the lower side sills 24 form outward base panels and the upper side sill panels 20 form opposite hull side walls The part-erected assembly of Figure 3A remains pliable at that stage as the panel hinges 37,38 have no particular bias or set and the fabric end walls 21, 22 simply restrain the outward splay of interconnected hull panels The next stage is to offer up the mid-span transverse seat panel 40 over the keel guide upstand 25 as reflected in Figure 3A.

This mid-panel 40 is then lowered over and located upon the keel guide upstand 25 and opposite upper side sill panel edges 23, as depicted in Figure 4A whereupon centre and side fasteners 65 are secured.

End wall panels 50, 53 are inserted before, after or contemporaneous with that, as also reflected in Figure 4A.

The next step is fitment of end seat panels 46, 47 which are depicted offered up in juxtaposition in Figure 5A. Once these are in place, intermediate side seats 48 are fitted between them and the centre seat 40.

Figure 6B depicts the end seats installed and end fasteners 60 secured 9/20 Generally, the seats have a scalloped inward edge profile to accommodate an occupants legs, and reduce the weight load Once all the seats 40, 46, 47, 48 are fitted and secured, partially-inflated peripheral buoyancy bags 70, 74 are fed underneath, then inflated in situ, and secured by straps 72 attached to the hull panels and fasteners 73 An alternative configuration is outboard buoyancy bags 76 as a stability aid, say with a bag at the prow omitted to help the boat make headway.

Fabric End Wall to Side Panel Edge Joint For a watertight hull, both the longitudinal intervening hinges between entrained hull panels and between fabric end walls and the hull panel ends must be rigorously water-tight with impermeable or sealed contact surfaces In the case of the joint between fabric panel to solid panel outer margin, a protected or shielded generous marginal opposed surface bonded overlap or overlay 34 is used, as reflected in Figure 2C A profiled moulded glass fibre finishing or trim strip 34 overlay serves as an inboard trim finisher and protective shield to an otherwise exposed edge joint of end wall fabric 21, 22 in a bonded sandwich between outer panel and trim profile with part edge wrap profile An upturned outer trim edge allows the fabric to fold about the upper hull panel end edge without cutting or abrasion.

Hinge Moulding A continuous moulded flexible hinge 31 section of synthetic rubber or other elastomeric material features a waisted or relatively slender spine 170, as depicted in Figures 2A, 2B to allow freedom of mutual entrained hull panel flex, to the extent of hinge limb fold back upon themselves for collapse panel fold as depicted in Figure 2E, with one panel folded back over another entrained panel.

An inner hinge 38 between hull mid span bottom panel 19 is flexed or turned through somewhat less of an included' angle than the hinge 37 between the upper 20 and lower 24 side hull panels which is turned through a minimal closing angle to allow panel overlay A certain very modest hinge flex may arise with differential water pressure on one (outboard) side once the hull is floated and the boat is put underway with attendant water movement, but this is countered by inherent panel bending stiffness and cross-bracing of end wall panel inserts 50, 53. Overall a modest degree of hull flex (perhaps minimal if not wholly imperceptible to a boat occupant) in reaction to applied loads is tolerable to re-distribute local stresses and counter fatigue stress through local stress concentrations and reversals.

A (slim or shallow depth) opposed skin intervening foam sandwich panel construction offers low overall density yet stiffness, but with ultimate flex rather than failure.

Hull End Wall Panels Opposite end panels 50, 53 serve to define the hull panel relative disposition and so the hull cross-section and outer boundary contour or profile at each end More specifically, the hull panels 19, 20, 24 sit within and alongside a marginal tray rim upstand 51, 54 on the opposite sides 10/20 and bottom of the inside face of each end panel 50, 53 The upper edges of the end panels 50, 53 have a folded over (N' or C') or hook-section profile with an open sided throat 55, 52 to contain the fabric wall 22, 21 upper edges and serve as a deeper top edge to complement the thickened top edge 23 of the side wall panels 20.

Fabric is left exposed on the inside faces of the boat hull, but once the end 46, 47 and side seats 48 are fitted, the fabric 21, 22 is somewhat protected from direct contact abrasion or scuffing The end seats 46, 47 fit at a level equivalent to the return depth of the end wall panel turn-over 55 and sit snugly upon a lip or ledge 56 at the foot of that return wall Spring over-centre fastener clips 61 between end wall 50, 53 and side wall panels 20 and between end seat 46, 47 and end walls 50, 53 are deployed to secure those elements snugly and securely together. A rectangular cut-out or scallop at the inboard edge of the rear seat panel 46 creates additional space or clearance for an occupant's legs.

Restraint Straps Guide sheaths are fitted to the inside faces of the upper and lower hull side panels for restraint straps 72 with snap-action buckle end fasteners 73 deployable to capture and entrain inflatable buoyancy bags 71, 75 located at the junction between lower side wall and floor, beneath seat level Fasteners Over-centre, snap-action fasteners 60 are fitted at strategic connections between key hull components and seat to fasten them securely together and resist unfastening under hull flex in use when water-borne. The fastener action lines' cross -so as collectively to pull transversely and longitudinally of the hull axis.

The hull end wall panels 50, 53 are pulled longitudinally towards the rear seat 46 by paired fastener set 65 upon the rear seat plane. Similarly, the opposite hull side wall panels 20 are pulled together transversely (or cross-beam) of the hull by paired fasteners 61 also set upon the rear seat plane. An equivalent or corresponding fastener array is employed at opposite hull ends for each end wall panel 50, 53 and associated end seat 46, 47, although seat profiles are adapted to location, with a generally deeper seat at the rear where occupancy is more likely for boat handling.

Cross-beam' fasteners 65 are also deployed to secure the centre seat panel 40 to the upper side wall panels 20 Locking pin fasteners (not shown) are employed to secure side seat panels 48 to the end and centre seat panels 45, 46, 40 with side panel end profiling noses 71 to fit complementary recesses 172 in end and centre seats upper surfaces. The side seats have a shallow curved outer profile to reflect that of the hull upper panels 20 and thus help preserve overall hull form integrity in use and resist hull distortion and flex from occupant and displaced water loading A turn-buckle rotary or swivel capture fastener 45 is used to pull the mid-span of the centre seat panel 40 down snugly upon and against the top flange of the keel centre board guide upstand 25 by engaging a recess or cut-out 27 in the underside outer edge of that flange. 11/20

The centre seat panel 40 serves as a mounting for ancillary fitting such as rigging stay or guy wire attachment points 94, 99. A mid-span throat slot in the centre seat panel 40 aligns with the internal guideway 26 of the keel plate upstand 25 Row-lock mountings 85 are secured to the internally-reinforced upper panel top edges 23 The row-lock oar capture fittings 85 with swivel pins might be removed from their mountings for and preparatory to hull panel in-fold.

Belt guide hoops are secured to the upper hull wall panels 20 above the likely water line and sealed to the lower wall panels 24 more likely to be immersed or submerged A mast base fitting 97 is secured to the bottom hull panel 19 somewhat forward of the keel guide upstand 25.

Fasteners lie generally internally of the collapse folded hull panels and are thus protected thereby.

The over-folded hull panels 20, 24 on each side of the hull base panel 19 form a convenient depth for gripping and handling. In particular the Intervening hinge offers supplementary grip and purchase against inadvertent slippage of hand grip. The hinges also serves as boundary edge protection in the collapse folded configuration.

Hinges The faces of the longitudinal hinge strips 31 exposed internally provide some modest anti-slip or grip qualities, along with a profiled or textured (say dimpled and! or ribbed) inner hull panel surface The hinge material is tough and resistant to scuffing such as from an occupant's feet Buoyancy Bag-Internal or External A convertible or interchangeable buoyancy bag 71, 75 format might be adopted, configurable alternatively for either (traditional) internal or (unconventional) external deployment. Mounting strap deployment would be adapted accordingly, Collapse Fold -Component Storage The in(ward)-folding hull panels 20 or overlying panel clusters 20, 24 admit an intervening gap or slot 1 l4of length represented by the mid base panel 19 about which, specifically about whose longitudinal edges, the opposed pairs of lower side panels 24 fold -ultimately to lie marginally spaced from, or in abutment with, a pronounced buffer rim of the central pillar or the keel guide upstand 25 from the base mid panel Storage Compartment The resultant intervening elongate channel or slot serves as a convenient elongate longitudinal storage compartment 114, for miscellaneous ancillary parts and equipment. The compartment 114 is interrupted and sub-divided, mid-span by the keel channel guide upstand 25, but deep storage is available on each side of sufficient width to accommodate what would otherwise be a disparate collection of loose components, such as seat seats, liable to loss or vulnerable to damage. 12!20

Flat-Pack Overall, a form of compact flat-pack storage could be contrived. This f tat-pack unit or module 10 might be carried upon, say, wall brackets as an elongate shallow depth package, of circa 8, 10 or 12ff in length by only a few (circa 6-8) inches in depth, so relatively unobtrusive in a domestic garage or shed The mast, boom, sail and rigging, might fit in another bag, as might the collapsed buoyancy bags 70, 74. Restraint straps or ties 111 might be fitted around the collapse-folded hull panels to keep the internally stored components securely in place Extension straps might also be used for suspending the hull and internal component pack, such as from a garage roof or ceiling joists A giant sling bag carrier, holdall or wrap with strap handles could embrace both folded hull assembly and internal captured or entrained components.

The ties for the buoyancy bags running through mounting loops and guides secured to the hull panel inside walls could be re-deployed for component restraint and overall package closure and suspension.

Tonneau Cover / Canopy / Component Wrap A stowable tonneau cover 132 could be fitted over the otherwise open hull for weather protection in open storage when erected. Such a cover could also be deployed across some part of the hull when in use, say as a spray protector. The cover could be run over or from a boom or spar to create a canopy tent or shelter with a supported ridge apex. When the boat is collapsed the cover could serve as a storage wrap for otherwise loose discrete components which can then be stored as a sandwich between folded together hull panels. Bespoke profiled compartments or pockets 135 with closure fasteners, tie bands or restraint straps could be incorporated for ease of component storage location and identification -so making it more evident when a component is missing, as its associated compartment is visibly empty.

Hull Panel A thickened top edge rim for the upper hull side panels is achieved by incorporating a marine ply timber fillet insert into the glass fibre mould.

This is useful for screw fastening and fixing ancillary fixtures and fittings from, say, row locks to tie mounts.

Folding Structure -Diverse Alternative Uses The foregoing folding mutually entrained panel structure described for a boat hull admits of adaptation to other diverse uses from, say other hull forms such as canoes, kayaks 17 to twin hulls 18 (catamarans) or double span hulls (tenders or barges). Even collapse fold storage sheds or houses might be contrived. These might find a use for emergency shelters or treatment units by aid agencies or, radically, temporary coffins. Thus, Figure 22B shows an inverted hull form of more rectangular section more suited to shelter and end wall access.

Buoyancy Bags Removable inflatable buoyancy bags 70/71, 74/75 are stowed under the end 46, 47 and side seats 48 with fill / deflation valves 78 canted uppermost for ease of access A stowable concertina collapse-fold fabric 13/20 bellows pump 173 is used for inflation. Bags 70, 74 are partially deflated for ease of installation while readily deformable or soft-walled Restraint straps 72 are fastened round the bags upon inflation. 14/20

Component List folded-in boat hull 11 folded-out boat hull 12 fully open boat hull 13 partially assembled boat hull 14 assembled boat hull folding boat hull 16 dingy folding boat 17 kayak folding boat 18 catamaran folding boat/twin hull folding boat 19 hull mid base panel upper side sill panel 21 bow membrane cover 22 stern membrane cover 23 top rail edge 24 lower side sill panel keel guide upstand 26 centre stand internal guide slot 27 aperture for seat toggle 28 inside top rail 29 centre board / dagger board fibre-glass panel 31 flexible rubber IH! jointing piece 32 fibreglass 33 foam core/fillet 34 sealed edging rubber grip deck 36 twin hull spanning deck 37 hinge between upper side sill & lower side sill 38 hinge between lower side sill & hull centre base panel centre seat 41 centre seat support 42 stern seat support 43 thwart support 44 underside of centre seat rotating toggle 46 stern seat 47 thwart 48 side seat 50 transom plate 51 transom plate tray rim upstand 52 transom plate open sided throat 53 bow plate 54 bow plate tray rim upstand 55 bow plate open sided-throat 56 transom lip upstand 57 bow plate lip upstand snap action fastener 61 fastener clasp between hull side panel and transom plate 62 fastener lever of hull side panel 63 fastener buckle of transom plate 64 fastener hinge of transom plate 15/20 fastener lever of centre seat 66 fastener lever of thwart inflatable buoyancy for internal side deployment (un-inflated) 71 inflatable buoyancy for internal side deployment (inflated) 72 securing straps 73 fastener 74 inflatable buoyancy for internal end deployment (un-inflated) inflatable buoyancy for internal end deployment (inflated) 76 inflatable buoyancy for external side deployment 77 detachable buoyancy 78 valve 79 buoyancy join rudder 81 rudder blade 82 lift/tilt mechanism 83 rudder handle 84 oars row locks 86 outboard motor mast 91 sails 92 folded mast 93 folded sails 94 rigging head sail 96 boom 97 mast base 98 bowsprit 99 forestays skeg wheel 101 automatic bailer folding boat components 111 straps 112 component bundles 113 stored component bundles 114 storage recess holdall bag for folded boat 121 attachment fixing for tube bag 122 tube bag for sails, mast and rigging 123 fastening 130 boat canopy 131 boat cover 132 tonneau cover 133 sling 134 boat canopy/cover accommodating component piece storage 135 pocket 136 fastening 137 folded boat cover 138 straps 139 handles 140 splittabledeckhull 141 cross seats 16/20 142 spray cover 143 canopy 144 canopy supports storage 150 folding house 151 door 152 windows 153 roof 154 external walls 155 modular house 156 internal door 157 internal wall folding coffin 161 coffin lid 170 hinge spine section 171 end nose of side seat 172 complimentary recess for side seat 173 pump 17/20

Claims (1)

1. Claims A collapse-fold 2-D flat panel assembly (11)is configured to form a prefabricated 3-D structure when erect, with intervening resilient panel hinges(31) between juxtaposed panel edges,to accommodate a complex 3-D erect form (12) A structure of Claim 1, configurable as a folding boat hull of panels (19, 20, 24) with intervening hydraulically-sealed hinge edge joints (37, 38) 3 A folding boat of Claim 2, configured as a plurality of longitudinal panels with intervening hinge seals, bridged at opposite ends by fabric panels, to contrive an overall buoyant erect hull form for flotation 4.

   A folding boat of Claim 3, with demountable (bench) seats (40,4647) fitted as cross-bracing at hull ends and centre span.

   A folding boat of Claim 4, with demountable side seats (48) fitted longitudinally between end (46) and centre (40) cross-seats 6 A folding boat of any of Claims 2-5, with a keel guide upstand 25 fitted to, or integrated (such as by moulding) with, a hull mid base panel (19), with an internal guide throat or slot (26) for a retractable dagger board (29) A folding boat of Claim 6, with a keel upstand peripheral rim configured to co-operatively interact with a slot in a mid-hull cross-seat. 8.

   A folding boat of any of Claims 1-6 demountable end panels (50, 53) fitted to brace respective fabric end walls (22, 21). 9

   A folding boat of any of Claims 2-8, with snap-action, over-centre security fasteners (60) fitted between seats and hull panels 10.

   A folding boat of any of Claims 2-9, with panels of synthetic plastics skinned foam sandwich construction, such as glass fibre reinforced material cladding a porous or void-laden substrate core A folding boat of any of Claims 2-10 with inflatable buoyancy bags (70) demountably fitted inboard or outboard of the erect hull with peripheral restraint straps or ties (72) A hinge for a folding structure, such as a boat hull, of any preceding claim, configured as a continuous multiple, in particular twin, arm profile of re-entrant capture throats for individual panel depths, upon a common integralspine 18/20 A hinge of Claim 12 of a continuous moulding or extrusion, of length corresponding to the span of conjoined panels.

   A hinge of Claim 12 or 13 dimensioned as an interference fit with panels to be conjoined.

   A hinge of any of Claims 12-14 bonded to panels to be conjoined A folding structure or boat hull of any preceding claim with one or more wheels or skids, fitted to an underside panel, for ease of ground transportation or movement of the entire assembly A multi-hull folding boat of any preceding claim, comprising two or more hulls conjoined, such as by a demountable transverse spar A folding boat of any preceding claim, split transversely, with abutting self-contained, individually-buoyant end (flotation) sections 19.

   A convertible cover, overlay or wrap, for a folding structure or boat hull of any preceding claim, to serve as a tonneau cover or canopy or convertible to a storage bag or holdall for boat components 20.

   A folding structure or boat hull of any preceding claim thereto, with a storage compartment defined between close-folded elements, for components or accessories 19/20