GB2048787A - Inflatable boat structure - Google Patents

Abstract

An inflatable boat structure comprises pneumatic tubular elements (1), defining the boat shape to the lower portion thereof a bottom cloth (2) is attached. A substantially rigid shell (3) is effective to be movably associated to the inside of the zone delimitated by said tubular elements and said bottom cloth. Said shell at least partially contacts said bottom cloth in such a way as to be effective to determine the shape of the boat keel. <IMAGE>

Description

SPECIFICATION Inflatable boat structure The present invention relates to a boat structure of the pneumatic type.

As it is known, the boats of pneumatic type, which in Italy are commonly called "gommoni", consist df one or more tubular pneumatic elements, forming the boat side edges and which, practically, define the shape of said boat, to the lower portion of said tubular elements being associated a cloth, this latter being generally formed by cloth portions as impregnated by elastomeric materials.

Said cloth practically forms the bottom of the boat and contacts the water.

The flexible cloth, which also forms the keel of the boat is, practically, maintained stretched in the transversal direction by the inflation of the tubular pneumatic elements forming the boat edge.

In order to longitudinally stretch the cloth, systems are nowadays used providing for a pneumatic type of keel, said keel being practically formed by a bottom pneumatic tubular element, which is stretched by inflation.

According to another conventionally used approach, is provided a rigid type of keel, generally made of wood, and located at the longitudinal middle portion, contributing to maintain stretched the cloth, jointly to the side ends of the dunnage; these latter are connected to the side pneumatic tubular elements.

In the two approaches thereinabove described, the bottom is only formed by a cloth, being more or less flexible, acting as a keel for the boat.

Accordingly, the water lines which may be obtained, and which practically provide the hydrodynamic attitude of the boat, are greatly variable depending on the dynamic loads and the cloth characteristics.

Between these latter are cited the resiliency of the cloth proper, the mechanical strength thereof and the yielding resistance thereof, in addition to the force which is necessary for stretching the cloth during the assembling operation.

Another drawback is furthermore the fact that, owing to the continuous shocking against water, during the sailing, the flexible cloth, forming the boat keel, is inevitably subjected to a vibration effect, which, practically, consists of a side skidding, causing parasite phenomena deteriorating a satisfactory "sliding" of the boat on the water.

Accordingly, the task of the present invention is to eliminate the thereinabove cited drawbacks, by providing a pneumatic type of boat structure which, in addition to be easily disassemblable and foldable, as the so called "gommoni" of known type, offers a possibility of making a permanent shape keel, i.e. a keel having a shape which is not affected in any ways by the dynam-ic loads on the boat and by the intrinsic characteristics of the cloth thereby the bottom cloth element is made.

Within that general task, a specific object of the invention is to provide a boat structure, of pneumatic type, which, while having all of the advantages usually present in this type of boat, offers the possibility of adopting a keel having an optimal shape for any specific types of boats.

Another object of the present invention is to provide a boat, of pneumatic type, effective to be easily disassembled and stored according to the conventional procedures.

Yet another object of the present invention is to provide a boat, of pneumatic type, which may be easily obtained starting from easily commercially available elements and materials and which, in addition, is highly competitive from a mere economic point of view.

Said task and objects, and yet other objects which will become more apparent thereinafter are achieved by a boat structure, of pneumatic type, according to the invention, comprising pneumatic tubular elements defining the boat shape.

At the lower portion of said tubular element a bottom cloth is associated, and a substantially rigid shell, effective to be movably associated in the inside of the zone defined by said tubular elements and said bottom cloth, is, at least partially, in contact with said bottom cloth, in order to define the shape of the keel of the boat.

Further characteristics and advantages will become more apparent from the following description of a preferred, though not exclusive, embodiment of a pneumatic type of boat structure, as illustrated by way of an indicative and not limitative example in the accompanying drawing, where: Fig. 1 is a cross-section view illustrating a boat according to the invention as provided with a rigid shell completely contacting the cloth; Fig. 2 is a schematic cross-section view illustrating a boat having a rigid shell partially contacting the cloth; Fig. 3 is a schematic perspective view illustrating a rigid shell formed by cross elements; and Fig. 4 is a schematic perspective view illustrating a rigid shell formed by longitudinal elements.

Referring particularly to the number references of said figures, the pneumatic type of boat according to the invention comprises one or more pneumatic tubular elements (1) defining the side edges and the bow zone of the boat and which, practically, define the shape of the boats itself.

Said tubular elements (1), which are of known type, are connected, at the lower portions thereof, by a bottom cloth (2) which is conventionally formed by cloth portions impregnated by elastomeric materials.

The characterizing feature consists in that in the inside of the zone delimitated by the tubular elements (1) and bottom cloth (2), it is provided a rigid shell, indicated generally at (3) (Fig. 1) which is in contact with the flexible bottom formed by the cloth (2).

Practically it is this rigid shell which determined the shape of the boat bottom and, accordingly, the desired shape of the bottom keel, this latter being not affected by changes during the sealing or even at rest.

As it is illustrated in Fig. 1, the shell (3) is provided with a substantially V-shaped crosssection and completely contacts the cloth (2).

Fig. 2 illustrates a conceptually analogous embodiment, the only difference being that the shaped shell, indicated at (34), is provided, at the middle portion thereof, with a longitudinally extending and projecting zone (4), meeting with planar portions (5) connected to slanted portions (6), at the sides of the cloth (2), near to the attaching zone of the tubular elements (1).

In this embodiment too, the shape of the keel is not determined by the flexible cloth but it is substantially defined by the shape of the rigid shell.

The rigid shell (3) or (3') has the characteristic of being an autobearing type of shell, i.e. it is provided with a suitable stiffness which, in addition to provide a keel of stable shape, acts as a strengthening or ribbing element for the boat thereto it is applied.

Said shell is movably applied on the cloth, i.e. it is practically maintained in positidn~by pneumatic tubular elements clamping said shell at the side edges and at the bow zone.

Advantageously it is possible to make said rigid shell by means of a plurality of composable elements, which are suitably located side-by-side and connected to one another, in such a way as to provide the desired stiffness for the structure.

As it is illustrated in Figures 3 and 4, the rigid shell (3) or (3') is made by using composable elements which can consist of cross elements, indicated at (10).

These latter are connected to one another by strengthening joints, for example of the cutch type, as it is indicated at (II) in the accompanying drawing.

Referring particularly to Figure 4, the rigid shell (3) or (3') is made by using longitudinal elements, indicated at (20), which are mutually located sideby-side and being provided, at the adjoining edges thereof, with suitable fixed joints, allowing for said cross elements to be easily coupled, and providing, in the meanwhile, a sufficient necessary stiffness.

By the proposed approaches is therefore obtained a shell effective to provide the desired shape of the boat keel, i.e. it provides the shape to be adopted by the bottom cloth (2).

Furthermore, in order to provide a more comfortable inside of the boat, a dunnage is provided, indicated at (30) and not described in further details since it is. of a type known per se, simply resting on the shell (3) or (3').

The use of the boat according to the invention is obvious, since it performs as a conventional boat, and furthermore provides the added advantage of presenting a permanent shape keel, since the bottom cloth does not form per se the keel, but simply the outside coating of a rigid shell, having a predetermined shape.

Furthermore, as thereinabove stated, the rigid shell, which may be easily disassembled in order to not present problems during the storing of the boat, helps, in a sensible and efficient way, to stiffen the boat, mainly in the transversal direction, and in the longitudinal direction, possibly by means of stiffening longitudinal members, constituting an integrant part of the rigid shell.

The invention as described is susceptible to several modifications and variations all falling within the inventive concept scope.

Furthermore all of the details may be replaced by other technically equivalent elements.

In the practice, the used materials, provided that they are compatible with the specific intended use, and the contingent shape and size maV be any, according to the needs.

Claims (8)

1. A pneumatic type of boat structure, comprising pneumatic tubular elements, defining the boat shape, to the lower portion thereof a bottom cloth is associated, characterized in that it comprises asubstantially rigid shell, effective to be movably associated to the inside of the zone delimitated by said tubular elements and a bottom cloth, said shell at least partially contacting said bottom cloth in such a way as to be effective to determine the shape of the boat keel.

2. A pneumatic type of boat structure, according to the preceding Claim, characterized in that said substantially rigid shell is provided with a substantially V-shaped cross-section and completely contacting the bottom cloth.

3. A pneumatic type of boat structure, according to one or more of the preceding Claims, characterized in that said substantially rigid shell is provided, on the cross-section thereof, with a middle projecting portion, thereto planar portions are connected, this latter being connected at the ends thereof to slanted portions, located at the pneumatic tubular elements, said cloth contacting said shell at the middle portions of said slanted portions.

4. A pneumatic type of boat structure, according to one or more of the preceding Claims, characterized in that said substantially rigid shell is formed by composable elements effective to be movably associated to one another.

5. A pneumatic type of boat structure, according to one or more of the preceding Claims, characterized in that said composable elements . are formed by cross elements effective to be coupled to one another by means of stiffening joints.

6. A pneumatic type of boat structure, according to one or more of the preceding Clairns, characterized in that said composable elements are formed by longitudinal composable elements, effective to be coupled at the adjoining edges thereof, bv means of fixed joints.

7. A pneumatic type of boat structure, according to one or more of the preceding Claims, characterized in that said substantially rigid shell acts as a stiffening element for said boat.

8. A pneumatic type of boat structure, according to the preceding Claims, and as broadly described and illustrated in the specification and several figures of the drawing accompanying the instant Patent Application.