The present invention concerns a hull of the type as stated in the introductory of claim 1.

Technical field

A need exists for a particularly light weight hull with sufficient strength to withstand the strain occuring when at least three people use the boat in demanding circumstances. Producing a hull from hollow profiles joined edge to edge to the shape of a hull is known. However, this method of construction is labour intensive and results in a relatively heavy construction, because of the crosspieces positioned on the edge of every hollow profile. From US Patent 3.093.847 it is known to produce a hull from panel shaped hollow profiles of plastic material, covered both on the internal and external surfaces by a plastic skin adhered to the same. Indeed, the use of hollow profiles provided with tongue and groove offers a certain degree of freedom to the hull shape, but both the basic construction and the covering with plastic plates is time consuming and results in a relatively heavy hull, at least heavier than with ordinary mold type construction.

NO Patent 148.913 discloses the production of a hull from hollow plastic boards joined together side by side. This method also does not sufficiently reduce the hull weight. It it possible to construct a light weight hull by using thin plastic plates, but such a hull will be so light that it will have poor stability in the water, particularly when used by one person alone. There is thus no known satisfactory solution which provides both low weight and good stability.

Object The main object of the invention is to provide a hull structure combining low weight, good stability and simple construction. A particular object is to provide a hull with sufficiently low weight to be lifted onto a car roof by one person.

Moreover, a further object is to provide a hull that in a simple way can be provided with ballast thereby providing sufficient stability in the water in spite of the low weight even when used by one person.

Invention

These objects are achieved by forming the hull in accordance with the characterizing part of claim 1. Further beneficial features appear firom the remaining claims.

Example

In the following, the invention is described in further detail with reference to the drawings, in which Figure 1 is a side view of a hull constructed in accordance with the invention, Figure 2 is a section taken on the line II-H across the boat axis in Figure 1, Figure 3 shows a section of a joint between the bottom and stern plate,

Figure 4 shows schematically a part of the boat stem according to Figure 1, and Figure 5 shows a section through a joint profile intended for a hull in accordance with the invention.

In Figures 1 and 2, an example of a hull structure according to the invention is illustrated. This hull is made up of two lateral plates 11 and two bottom plates 12 mutually joined side by side. The lateral plate 11 and the bottom plate 12 at each side are joined along a bottom joint 13, whereas the two bottom plates 12 are joined along a central keel joint 14. Joints 13 and 14 are described below in further detail with reference to Figures 4 and 5.

Side plates 11 and bottom plates 12 are cut from channelled plates, e.g. of polycarbonate or PVC, -comprising double layered plates with intermediate channel forming ribs. Such plates are commercially available and exist in different dimensions, materials and structure. A common property of such plates is a favorable relationship between strength and weight, relatively low price and simple processing. They can be cut by ordinary saws and joined by gluing in several ways. The side plates 11 and bottom plates 12 are narrowed at the front end, foπriing an

ordinary stem shape with protrusions in two directions.

At the hull stern, a vertical stern plate 15 is positioned enclosing the hull at the end of the remaining plates. The joint can be constructed as shown in Figure 3, with an angle profile 16 at the edge supporting the outside of side plates 11 and bottom plates 12 closing channels 17 and covering the edge of stern plate 15. Preferably, the stern plate 15 is oriented with horizontal channels, thereby closing the upper edge thereof.

To buttress the upper part of the hull, a selvage of e.g. plastic, aluminum or wood can be mounted. Moreover, the stern plate can be provided with a buttress plate intended for an outboard motor.

Moreover, seats, optionally provided with floating elements, can be mounted with the hull in a manner known per se.

At the rear egde of the bottom, there is provided a hole 18 from the external side into each channel 17 to establish fluid communication between the latter and the surrounding water. The purpose of this will be apparent from the description below.

In Figure 4 there is further illustrated a part of the stem section 19 between the bottom and side plate 11 joint area 20 at the stem. The bottom plates 12 are joined to a double channel 21, so that the channels 17 in the bottom plates run into its respective channel parts 21A and 21B respectively. At the upper edge, these double channels are joined by two end branches 22A, 22B of a discharge pipe 22 extending up to the upper edge of the hull and further provided with a simple valve for closing and opening. In the example, the valve comprises a plug 23 intended for insertion into the pipe end.

When launching the hull, water will penetrate through holes 18 into channels 17 in the bottom plates 12. When the pipe 22 is open, this water is permitted to fill the channels to the level of the surrounding water. When using the boat on the water, the plug 23 is inserted and the bottom plates 12, filled with a ballast means, provide stability to the boat. When the boat is to be put ashore, the plug 23 can be removed to empty the channels through holes 18. In this way, the boat can be provided with a low weight for transportation and with a heavier and more stable weight for the intended use.

In Figure 5, an example of a joint profile 24 for joining the hull plates is

illustrated. The joint profile comprises two TJ-shaped channels 25 A, 25B intended for attachment to the plate edge. The two U-shaped channels 25 A, 25B are combined with a step 26 at one side, in the example internally, having an integrated intermediate longitudinal sausage shaped hollow bar 27 extending to the opposite side. The joint profile 24 is formed from a plastic material having a certain degree of elasticity, such as PVC.

During construction the U-shaped profiles 25A,25B are guided around the edge of the adjacent plates and at the same time a suitable adhesive is applied. The hollow bar 27 is dimensioned to extend laterally, thereby providing a stabilizing fin on the boat when in use. Moreover, the dimension laterally is determined in such manner that the lateral edges locate towards the end of the respective U-shaped profile for the case when the plates form the smallest mutual angle in question. When mounting, in the case this angle is greater than the minimum angle, the U-shaped profile will compress the elastic bar 27. Optionally, an adhesive can be applied between the different parts to buttress the joint. Moreover, in the example, a reinforcing strip 28 is applied internally along the joint, covering the sides of the U-shaped profiles 25A,25B and adjacent plate areas. The reinforcing strip 28 is glued in a suitable manner. The internal sides in the U-shaped profiles 25A,25B can be stepped at 29 to establish a stop for the plate edges and thereby an internal longitudinal channel 30 capable of connecting the channels 17.

The plate connections in the hull may be accomplished in different ways, e.g. with connecting selvages having an H-profile and elastic properties, by welding the plate edges, with strips appllied internally and externally, or combinations thereof. The hull examplified above can be modified and completed to provide a boat in different manners within the scope of the invention. For example, a combination of single and double layered plates or of single layered plates and additional channel forming plates in the bottom can be used. i this way, it is possible to provide a known shell boat and in accordance with the invention attach channelled plates or similar plate structures, having a ballast chamber, externally or internally to the underside, assuming of that the boat is provided with a ballast area at the bottom, to be filled with sea water in a convenient manner prior to its use, and similary conveniently emptied for transportation or storage.

The hull in accordance with the present invention can be completed to provide a boat by using different known constructions, such as seats, edge buttressing, mounting means for an outboard motor and oarlocks, floating containers and the like. Thus, the invention comprise both a hull and a finished boat and semifinished product for the production of a hull according to the invention.