Surfboard with overlap

Abstract

The invention relates to an inflatable surfboard having a hull component (2) with a receptacle (4) at the stern end, a drive unit (3) which fits into the receptacle (4) at the stern end in a positively locking manner, and a gap (6) on the underwater surface between the hull component (2) and the drive unit (3), wherein an overlap (8) which covers the gap (6) at least in some sections is arranged on an underwater surface (7) of the hull component (2).

Claims

1. A Surfboard comprising: a hull component (2) with a receptacle (4) at a stern end, a drive unit (3) which fits into the receptacle (4) at the stern end in a positively locking manner, a U-shaped gap (6) on an underwater surface (7) between the hull component (2) and the drive unit (3), an overlap (8) which covers the gap (6) at least in some sections is arranged on the underwater surface (7) of the hull component (2) characterized in that the overlap (8) is adapted to the configuration of the gap (6) and the overlap (8) is formed as a U-shape stripe and is a flap.

2. Surfboard according to claim 1, characterised in that the hull component (2) is inflatable.

3. Surfboard according to claim 1, characterised in that the hull component (2) has two lateral arms which engage in a U shape around the drive unit (3), and the overlap (8) is likewise U-shaped and at least covers a section of the gap (6) at a bow end.

4. Surfboard according to claim 1, characterised in that a releasable fastening means is arranged between an inner side of the overlap (8) and the underwater surface (7) of the drive unit (3).

5. Surfboard according to claim 1, characterised in that the overlap (8) is open towards the stern end.

6. Surfboard according to claim 1, characterised in that on a leading edge in a direction of travel (F) the overlap (8) is chamfered towards the underwater surface (7).

Description

(1) The invention is described with reference to an embodiment in six drawings. In the drawings:

(2) FIG. 1 shows a schematic sectional view of a conventional surfboard,

(3) FIG. 2 shows a view of a detail of the gap between the hull component and the drive unit,

(4) FIG. 3 shows a sectional view according to FIG. 1 of the surfboard according to the invention with the overlap,

(5) FIG. 4 shows a view of a detail of FIG. 3,

(6) FIG. 5 shows a view from below of the surfboard according to the invention with the overlap between the hull component and the drive unit,

(7) FIG. 6 shows a view of the surfboard according to the invention with the overlap.

(8) FIG. 1 and FIG. 2 show surfboards 1 according to the prior art. The surfboard 1 has a hull component 2 which is inflatable. In a view from above the hull component 2 is substantially U-shaped in a stern section. A drive unit 3 is introduced into a U-shaped receptacle 4 of the hull component 2.

(9) The hull component 2 can preferably be made from a drop stitch material. The drop stitch material is produced by the drop stitch method, wherein two or more synthetic fabric webs, preferably denier polyester fabric webs, are laid one above the other. The two synthetic fabric webs are connected to one another by a plurality, i.e. thousands, of polyester threads. In this case the maximum spacing of the two fabric webs is fixed, so that the space between the fabric webs which is filled with polyester can be filled later with compressed air and the fabric webs are then substantially parallel to one another. The polyester threads are sewn on both sides to the two fabric webs, for example with the aid of a drop stitch sewing machine. The two fabric webs which are sewn to one another form the support structure which gives the hull component 2 its mechanical strength in the inflated state.

(10) The two fabric webs which are connected to one another are cut to the required shape. The upper and the lower fabric webs are preferably coated with PVC layers, preferably with three layers, and are pressed and glued in layers. The faces are glued, overlapping, to the seam strip and are pressed, so that the airtight hull component 2 is produced.

(11) The drop stitch method makes it possible to produce the inflatable hull component 2 with outstanding mechanical strength properties, which withstand not only tensile loads but also compressive loads and shearing loads. The drop stitch outer skin of the inflatable hull component 2 is airtight and in the inflated state is exceptionally resistant to deformation, so that a surfer can stand and surf on the hull component 2 whilst retaining the external shape of the inflated hull component 2. The inflatable hull component 2 is filled with air under high pressure. The filling can take place by means of an air pump or a compressor. The compressor can be supplied with electrical power by batteries incorporated in the surfboard 1.

(12) The hull component 2 made from the drop stitch material is preferably sound-damping, so that the volume of sound generated by the breaking of waves, but also by the drive, is damped by the hull. The hull component 2 is subject to little vibration during operation, because vibrations are reduced by the drop stitch material. Since the hull component 2 is somewhat deformable, impacts and waves etc. are advantageously absorbed. Furthermore, by comparison with conventional surfboards 1 it is advantageous that the softer hull causes fewer injuries, for example if the surfboard 1 collides with the surfer in the event of the surfer falling off.

(13) The stern region of the hull component 2 includes the receptacle 4 for the drive unit 3. The drive unit 3 can comprise a jet drive. The jet drive comprises an opening for the water inlet on an underwater surface 7 of the drive unit 3 as well as a water channel towards the stern end surface of the drive unit 3. The water outlet can be formed there by a nozzle. The nozzle can be arranged pivotably or fixed.

(14) In the water channel a rotor is provided which, due to its high rotational speed in operation, draws water into the water channel and sprays it out rearwards through the nozzle and thus gives the surfboard 1 the propulsion. The rotor is connected by means of a drive train to a motor, preferably an electric motor which is optionally controllable by means of a controller and is supplied with power by means of the battery. The drive unit 3 as a whole is replaceable. The term “rotor” should be understood broadly here. It may be a propeller, an impeller or the like.

(15) A gap 6 is produced between the drive unit 3 and the hull component 2. Since the hull component 2 has a convex configuration into the receptacle 4 along a lateral inner wall running around about three-quarters of the drive unit 3, an outer periphery of the drive unit 3 is adapted in a positively locking manner to this contour, but this adaptation may never be so exact that no gap 6 is produced, in particular not directly on the underwater surface 7, on the joint between the hull component 2 and the drive unit 3. In the illustration in FIG. 2 the width of the gap 6 is exaggerated. However, the problem is discernible that during the ride on the surfboard 1 water is really forced into the gap 6 due to the flow speed. The current of water is illustrated by the longer arrows. A direction of travel F of the surfboard 1 is illustrated by a broad arrow.

(16) FIG. 3 shows the surfboard 1 according to the invention which has an overlap 8 on the underwater surface 7. The overlap 8 is a flap made from PVC, PE, PET or another plastic material, which is likewise U-shaped in a view from above substantially according to FIG. 5 and covers the gap 6 at least in some sections. However, the overlap 8 can also be made from leather or other natural materials or also a metal foil. The overlap 8 is in particular provided at a gap section 6a which is arranged transversely in the direction of travel F, and is located between a leading edge of the drive unit 3 in the direction of travel F and a corresponding, transversely arranged inner wall 2a of the hull component 2, and completely overlaps the transversely extending gap section 6a. The flap 8 is firmly sewn, glued or welded to the hull component 2. For this purpose a welded, glued or sewn seam 9 is provided, or a plurality of welded, glued or sewn seams 9 are provided, which follow(s) the edge 11 of the overlap 8 remote from the receptacle 4. The edge 11 which runs ahead of the overlap 8 in the direction of travel F or runs at the side thereof is preferably chamfered in the direction of travel F and glued to the hull component 2 along the entire edge 11 so that, even during the ride through the water current no water can penetrate between the underwater surface 7 of the hull component 2 and the overlap 8, but the water current according to FIG. 4 is deflected below the flap. The overlap 8 can be releasably connected to the drive unit 3 in a section which overlaps with the drive unit 3; in this connection a hook-and-loop fastener 12 according to FIG. 3 or the like can be formed between the edge of the overlap 8 facing the drive unit 3 and the drive unit 3 itself.

(17) The overlap 8 preferably rests closely and without creases on the underwater surface 7 of the drive unit 3.

(18) FIG. 6 shows the overlap 8 in a view from below. The view from below shows the U-shaped receptacle 4 which is formed by the hull component 2. Inflatable arms of the hull component 2, which are circular in cross-section perpendicular to the direction of travel F, and which between them engage around the drive unit 3, are arranged laterally on the drive unit 3. On the forward part of the drive unit 3 in the direction of travel F the overlap 8 is provided which is connected to the hull component 2 and which does not necessarily completely cover the gap 6, but completely covers the gap section 6a which extends transversely, preferably perpendicularly to the direction of travel F and into which a particularly large amount of water has penetrated.

LIST OF REFERENCE NUMERALS

(19) 1 surfboard 2 hull component 2a inner wall 3 drive unit 4 receptacle 6 gap 6a gap section 7 underwater surface 8 overlap 9 welded or sewn seam, fastening line 11 edge 12 hook-and-loop fastener F direction of travel