WATERCRAFT

Abstract: A watercraft, principally for use by one person and which comprises a buoyant body slightly longer than the height of the user and which is adapted to carry an outboard motor at its stern and may be equipped with hydrofoils (40). The body may consist of a plurality of interfitting, releasably interconnected self-buoyant parts.

Description: Title: "Watercraft" THIS INVENTION relates to watercraft and is particularly concerned with a small, lightweight watercraft, for example for sporting and amusement purposes. It is among the objects of the invention to provide a watercraft adapted for ease of transport by motor car or the like vehicle. According to one aspect of the invention there is provided a watercraft comprising a bouyant body consist¬ ing of a plurality of interfitting self-buoyant parts detachably secured to one another by readily releasable fastening means, whereby the craft can readily be broken down for ease of transport or storage and re-assembled for use. It is another object of the invention to provide a light, portable watercraft adapted to be readily carried and handled by a single person and which is motorised. According to another aspect of the invention there is provided a watercraft comprising a bouyant body of a size to accommodate one or two persons and fitted with a detachable propulsion unit. Preferably the craft is equipped with hydrofoils. In a preferred embodiment, the watercraft is configured to accommodate a person in a prone position, said propulsion unit, together with steering means being located, in use, aft of the user's feet, the craft including, in the region of the bow, hand grip means and associated manually operable control means and control transmission means extending from said control means, through the body of the craft, to said propulsion unit and steering means. An embodiment of the invention is described below by way of example with reference to the accompanying drawings, in which:- FIGURE 1 is a perspective view of a watercraft embodying the invention; FIGURE 2 is an exploded perspective view of a variant of the watercraft of Figure 1 showing various component parts thereof; FIGURE 3 is a further exploded perspective view of the craft, FIGURE 4 is a schematic view in longitudinal section showing the manner in which component parts of the craft are secured together detachably; FIGURE 5 is a plan view of the craft from above; FIGURE 6 is a corresponding plan view showing how the user of the craft occupies the same; FIGURES 7 and 8 are views respectively from below and above of one component of the craft, FIGURE 9A is a perspective view, FIGURE 9B an exploded perspective view and FIGURE 9C a plan view of a fuel tank and engine unit forming part of the craft, and FIGURE 10 is a schematic side view showing th craft in use. The craft to be described with reference to th drawings is intended to form a motor-driven counterpar to the sail-powered surfboards which have become popula in recent years. Thus, it is contemplated that the craf will be, for example, from six to eight feet long, an two to three feet broad, with a mean depth of around on foot. The craft comprises a plurality of detachabl interconnected body units, each having an impermeabl outer shell of plastics such as vacuum formed ABS sheet, filled with foamed plastics, such as polyurethane foam, to render the craft unsinkable. Referring to Figures 6 and 10, it is intended that the user of the craft, hereinafter referred to as the pilot, should lie prone, on top of the craft, looking forwards over the bow and holding, by respective hands, grip and cont ol members 30 adjacent the bow, on either side. As shown in Figure 1, the upper surface or deck of the craft is generally horizontal over the major part of the length of the craft but rises, towards the bow, over a hump formation 32 which, from its highest point, tapers downwardly once more, to the point of the bow. The part of this formation which rises towards the bow is intended to support the trunk and thorax of the pilot. The formation 32 is so dimensioned as to allow the arms of the pilot, lying in this position, to pass on either side of formation 3 to reach the control members 30. To provide firm location for the body of the pilot, and also for comfort, the deck of the craft is formed with a shallow recess bounded on either side by raised bulwark portions 34, this recess also extending over a middle portion of the rising surface of the hump formation 32, to receive the chest and shoulders of the pilot. This recessed deck portion is furthermore preferably covered by an appro¬ priate anti-slip material, which preferably is also of a soft and resilient nature for comfort. The aftermost part of the stern of the craft is provided by a generally U-shaped member 36 lying in a horizontal plane and defining, with the rear edge of the plastics/foam body, an open loop. The member 36, preferably formed of lightweight metal tubing, or strong plastics, forms a mount for an outboard motor (not shown) . On either side of the craft, at the stern and towards the bow, are provided respective hydrofoils 40, which may be of stainless steel; aluminium alloy, glass or carbon fibre reinforced plastics, for example. The outboard motor (not shown) may be of sub¬ stantially conventional design, with such modification as may be necessary for mounting on the member 36, and the controls for the motor, including the throttle as well as the means for pivoting the motor about a substantially vertical axis for steering purposes, in the conventional manner, are operatively connected with the control member 30 by means of Bowden cables (not shown) which extend through channels defined between inter- connected body units as will become apparent. In use, the pilot lies prone upon the craft, gripping the control members 30 and, by appropriate movement of the latter, steers the craft and controls the motor output and thus the speed of the craft. At low speeds, the craft simply floats in the water, but as speed increases, the craft rises and is supported by the hydrofoils, allowing increased speed with little increase in drag, and thus allowing higher speeds to be achieved without great power being required. Referring to Figure 4, the craft may comprise four detachably interconnected body units including a fore bottom unit 50, a fore upper unit 60 providing the hump formation 32, an aft unit 62 and a fuel tank and engine mount unit 64. The units may be held together by vertical screw bolts 66, 68, 70 adapted to be unscrewed by hand or by means of a simple tool. Thus, the unit 60 is superimposed upon the unit 50 and is secured thereto by means of the bolt 66 extending through a vertical passage in the unit 60 and engaged in a screw threaded passage extending from the upper surface of the unit 50. The forwardmost part of the unit 62, in the region between the lateral zones thereof which afford part of the bulwark portions 34, is recessed on its upper and lower sides to accommodate the rearward end portions of the units 50 and 60 respectively, so that this recessed portion of the unit 62 is clamped between the units 60 and 50. The bolt 68 extends through a passage in the aftermost part of the unit 60, through a vertical passage in the a orementioned recessed part of the unit 62 and into an internally threaded bore in the aftermost part of the unit 50. The upper surface of the unit 62 is similarly recessed at its aftermost end to accommodate the body of the unit 64 which is fitted in said recess and is secured to the unit 62 by the bolt 70 extending through a vertical passage in the unit 64 and into a screw threaded bore in the unit 62. Figure 2 illustrates a variant in which the craft is of substantially unitary construction. The craft is shown partly exploded in Figure 2 to illustrate the manner of manufacture, which is similar to that utilised for the individual units in the multi-unit embodiment of Figure 4. Thus, the body of the craft in the variant of Figure 2 comprises an upper shell part, vacuum-formed from ABS sheet material, a lower shell part formed in the same manner, the two shell parts being sealed together around their peripheries and the space defined between the shell parts being filled with polyurethane foam. In this variant, the motor mount 36 is located between the two shell parts before these are secured together. The control cables from the control members 30 to the outboard motor unit may, in the multi-unit embodi¬ ment, be accommodated within passages defined between, on the one hand, channels 71 formed in the underside of the shell of the unit 60 (see Figure 7) and the upper surface of the unit 50. The cables may be located within relatively large-diameter plastics tubes 69 , (Figure 3) adapted to fit in said passages, said tubes being detach¬ able from the rest of the craft, with the cables still within said tubes, when the craft is "broken-down" for storage and transportation, allowing the tubes, with the cables still within, to be stowed neatly away. In the unitary construction of Figure 2, the control cables may be accommodated within tubes appropriately arranged and located between the upper and lower shells before the foam is formed, ija situ, between the shells. In the embodiments described, the hydrofoils 40 are preferably detachable from or releasably securable to the otherwise complete or completely assembled body of the craft, in a simple manner (not illustrated) allowing the craft, for example, to be used for a period without the hydrofoils, and then fitted with the hydrofoils without disconnecting the units 50, 60, 62, (in the case of the multi-unit embodiment) or vice versa. Alternatively, the hydrofoils may be permanently secured to the craft. As illustrated in Figures 9A, 9B and 9C, the unit 64 includes a hollow body part 65 adapted to accommodate a liquid fuel tank. The member 36 forms a handle by which the unit 64 can be carried, with the internal fuel tank, when the unit 64 is detached from the remainder. It is conceivable that the unit 64 and the outboard moto attached thereto may be removed from the remainder as a integer, for appropriate storage. In Figures 9A, 9B and 9C, the reference 67 denotes a filler opening, provided with a removable closure (not shown) and through which fuel may be passed into the fuel tank. The possibility of breaking the multi-unit version into four major parts (plus, of course, the four hydrofoils) facilitates storage and transport of the craft so that it may be possible, for example, to accommodate the entire craft, in broken down form, within a car boot or in a garden shed or the like without a special roof rack, trailer or storage accommodation being necessary. The various parts may be fitted into a appropriately configured canvas or plastics storage case for transport or storage. Such a case may take the form, for example, of a large suitcase, with a handle or handles allowing the craft to be carried by hand, without any trailer or the like being required. In a further variant, not shown, the craft comprises an inflatable body of impermeable, flexible material which can simply be deflated and folded or rolled up for storage and transportation. A craft embodying the invention preferably has various further, safety features. Thus, for example, it is contemplated that the outboard motor will have a cut¬ out device connected in use, with a lanyard fastened to some point on the pilot's body, for example fastened around the pilot's ankle, so that if the pilot should become separated from the craft, the motor wiil be stopped automatically. In the interests of safety, the outboard motor may incorporate a ducted propeller, i.e. the propeller may be mounted within a stationary duct or tube, an arrangement which, besides minimising the risk of injury to the pilot or other water users from the rotating propeller, can also improve the efficiency of the propeller. It is contemplated that, at least in some versions, a craft embodying the Invention may utilise a motor of modest power, for example of 9 to 15 HP and may be otherwise designed for only modest speeds, so that it can be used safely by children. Whilst the craft described is intended for a solo pilot, it will be appreciated that by making the craft somewhat larger, with some adaption of the form, it may be made suitable to carry two persons.

Claims: CLAIMS 1. A watercraft comprising a bouyant body consisting of a plurality of interfitting self-buoyant parts detach- ably secured to one another by readily releasable fastening means, whereby the craft can readily be broken down for ease of transport or storage and re-assembled for use. 2. A watercraft comprising a buoyant body of a size to accommodate one or two persons and fitted with a detachable propulsion unit. 3. A watercraft according to claim 1 or claim 2 which is equipped with hydrofoils. 4. A watercraf.t ' according to claim 2 or claim 3 which is configured to accommodate a person in a prone position, said propulsion unit, together with steering means, being located, in use, aft of the user's feet, the craft including, in the region of the bow, hand grip means for the user's hands, and associated with said handgrip means, manually operable control means associated with said hand grip means, and control transmission means extending from said control means, through the body of the craft, to said propulsion unit and steering means. 5. A watercraft substantially as hereinbefore des¬ cribed with reference to, and as shown in, the accompany¬ ing drawings.

Inventors: CAWOOD GAVIN, JOHNSON WILLIAM NEVIL HEATON, CAWOOD, GAVIN, JOHNSON, WILLIAM, NEVIL, HEATON
Applicants: SCIENT APPLIED RESEARCH SAR, SCIENTIFIC APPLIED RESEARCH (SAR) PLC.
Application year: 1988
Main classification: B63B35
IPC codes: B63B35