GB2187678A - Boats - Google Patents

Abstract

A very light but strong boat is formed by providing a deck (1) and floor (2) as main structural members with braces (3) therebetween and a waterproof covering. The deck (1) and floor (2) are initially planar members and are sprung together with the braces (3) therebetween and anchored at the bow (4) and stern (5). The braces tie the deck and floor into a cantilever construction and foam buoyancy material may be bonded to the underside of the deck and/or floor. A tripod mast and lanteen sail may be provided. <IMAGE>

Description

SPECIFICATION Improvements relating to boats The invention relates to boats.

Previously proposed boats can be categorised by theirbuilding methods and these include: Inflatable: the hull sides and bottom are formed by inflated tubes providing rigidity, form and emergency buoyancy, examples include zodiacs and liferafts; Rigid framed: struts and braces in the form of a keel,frames and stringers are used to give form and rigidity to a skin, sub-forms include clinker, carvel conventional hulls, canvas-covered canoes, and curraghs; and Monocoque: the skin, suitably reinforced, provides its own stiffness and strength, forms include GRP, cold-moulded veneer and double-diagonal.

According to the invention a boat comprises a deck and a floorforming main structural members, the deckandthefloorbeing initially generally planar members and being sprung together with braces therebetween, anchored atthe bow and stern and provided with a waterproof covering.

The braces tie the deck and floor into a lightweight cantilever structure. Atransom may be provided at the stern bolted to rear braces to form a stiff box section. The transom may be a flat transom board suitable for the mounting brackets of an outboard motor.

Foam buoyancy can be bonded to the underside of the deck and/or the floor preferably prior to provision of the waterproof covering.

The hull of a boat according to the invention can be strong, light and stiff. Twisting and bending moments are limited by the braces connecting the deck to the floor. In a sailing version, rigging tensions can be distributed onto the waterproof covering. Compressive mast forces are transferred to the floor via the braces. Seats can be fitted into the braces and logs to support a centreboard can be slung beneath the seats.

The structural members can thus be provided only at locations atwhich people are likely to sit or move, and where loads will be carried. The rest ofthe hull can be as light as possible, consistent with safety. By springing the deck and floor into a cantilever, enormous strengths can be developed in the structure which exceed the sum of their individual parts when placed in other, conventional configurations. This enablesthe hull to befarlighter than would be normal for a boat of the same size.

The manufacturing advantages are considerable.

Material costs can be low, and the floor, and deck, and all other parts can be prefabricated flat. The braces can be fitted to the deck and the floor bent to shape. None of the customary and expensive boat building skills are required to perform any of these operations.

The commercial appeal ofthe boat is its lightness and low cost. The boat can be easy to carry and have a remarkable performance.

In asailingversion of boat according to the invention the mast may be a tripod mast. This can permit the full benefits of a traditional and efficient lateen sail to be utilised, without the attendant windward problems associated with this sail when it is set on a single mast. A rudder of the boat may have its structure simplified to a blade and steering bar.

Metalwork whereby the rudder is mounted on the boat can merely provide a minimum of lateral support and a simple pivot with the rudder blade being stabilised against oscillating movements by a steering bar pivoted to its upper end.

The invention is diagrammatically illustrated by way of example with reference to the accompanying drawings in which Figure lisa perspective view of a hull of a boat according to one embodiment of the invention; Figure2 is an elevation corresponding to Figure 1; Figure 3 is a perspective view of another embodimentofa hull of boat according tothe invention; Figure 4 is an elevation corresponding to Figure 3; Figure 5 is a transverse section corresponding to Figure 4; Figure 6 is a perspective view of a third embodiment of a boat according to the invention rigged for sailing; Figure 7 is a side elevation of a rudder on a boat according to the invention in an operating position; and Figures a view corresponding to Figure 7 but with the rudder in a raised position.

Referring to the drawings and firstly to Figure 1, the hull ofa boat comprise a deck 1, afloor2 and braces 3. The deck 1 and floor 2 are fabricated flat, are bentto the shape shown with the braces 3 therebetween and are secured together at the bow and stern as shown at4. After providing the hull with a waterproof covering it can be used for example as a canoe or rowing boator, in conjunction with another similar hull and a bridging member, in a catamaran form.

In the embodiment of Figures 3to 5, the deck 1,the floor 2 and the braces 3 are ofsimilarform to those of the embodiment of Figures 1 and 2 and the deck 1 and the floor 2 are secured together at the bow at4 as previously.

At the stern however a transom 5 is provided secured to the deck 1 and floor 2 by braces 6to form a rigid box section. Figure 3 also shows thwarts 7 secured to the braces 3 for use as seats and Figures 4 and 5 show foam buoyancy 8 provided on the underside of the floor 2. Awaterproof skin 9 is indicated in Figure 5.

In the embodiment of Figure 6, the hull is generally formed as in Figures 3,4 and 5 but a centreboard box 10 is provided supported by the thwarts 7.

Atripod mast 11 is provided to support a lateen sail 12, a goose neck 13 being provided on a cross member 13 joining two rearward members ofthe tripod mast 11. During sailing ofthe boat of Figure 6 the forward member of the tripod mast may be subjected alternatively to tension and compression according to the mode of sailing. The waterproof covering 9 may be rigid or may be provided so that it can flex. The braces 3 and 6 are located so as to preventtorsional movement of the hull.

The rudder arrangement shown in Figures 7 and 8 and also in Figure 6 comprises a simple framework 14to be pivoted on the hull about an upright pivot axis by a pin 15 and mounting a rudder blade 16 by a transverse pivot pin 17. A steering bar 18 is pivoted by a transverse pivot pin 19to an upwardly and rearwardly curved extension 20 of the rudder blade 16,the upper end ofthe rudder blade engaging in a slot in the steering bar 18 in a manner such that oscillation ofthe rudder blade 16 about a vertical axis can be restrained by the steering bar 18. The rudder blade can be stabilised and locked in the down position by a clip 21. Raising and lowering ofthe rudder blade 16 can be effected bythesteering bar 18.

Claims (10)

1. A boat comprising a deck and a floorforming main structural members, the deck and the floor being initially generally planar members and being sprung together with braces therebetween, anchored atthe bow and stern and provided with a waterproof covering.

2. A boat according to claim 1, in which the bracestiethe deck and floor into a lightweight cantilever structure.

3. A boat according to claim 1 or claim 2, including a transom atthe stern bolted to rear braces to form a stiff box section.

4. A boat according to claim 3, in which the transom is a flat transom board suitable forthe mounting brackets of an outboard motor.

5. A boat according to any one of claims 1 to 4, including foam buoyancy bonded to the underside of the deck and/or the floor.

6. A boat according to any one of claims 1 to 5, including seats fitted into the braces and logs to support a centreboard slung beneath the seats.

7. A boat according to any one of claims 1 to 6, in which structural members are provided only at locations at which people are likely to sit or move, and where loads will be carried.

8. A boat according to any one of claims 1 to 7, including a tripod mast and lateen sail.

9. A boat according to any one of claims 1 to9, including a rudder with its structure simplified to a blade and steering bar, metalwork whereby the rudder is mounted on the boat providing a minimum of lateral support and a simple pivot with the rudder blade stabilised against oscillating movements by a steering bar pivoted to its upper end.

10. A boatsubstantially as hereinbefore described and illustrated with reference to the accompanying drawings.