EP0040757A1 - Windsurf board - Google Patents

Abstract

Windsurf board which is formed from fibre-composite laminated layers - oriented in accordance with the forces to be absorbed - and if need be from a shear binding (14) of foamed plastic or fibre composites. <IMAGE>

Description

The invention relates to a windsurf board known for use in water sports.

The aim of all of the various types of windsurfing or sailing boards that have become known is that the hydrostatic buoyancy is achieved with the smallest possible volume of the board itself, ie. H. the weight or the specific weight of the board should be kept as small as possible. Now, due to the loads to be borne, the operability and the various hydrostatic and hydrodynamic conditions, these requirements are subject to limits that could not be undercut without affecting the power conditions.

The present invention is based on the object of decisively reducing the limits previously set in reducing the specific weight and of considerably reducing the system weight.

This task is solved in a reliable and optimal manner by the measures set out in the claims, whereby the construction volume of the board and thus the mass can be significantly reduced. The measures shown at the same time make the wetted surface smaller and thus the hydrodynamic resistance. The resulting reduced system weight also has the advantage that the board can get into the more resistant sliding phase at reduced or low speed and thus the effective sliding number is considerably improved. Of course, the handling and the Transport of the device considerably improved.

• Fig. 1 eine Draufsicht auf das beschriebene Ausführungsbeispiel in schematischer Darstellung,
• Fig. la einen Schnitt entlang der Linie A-A gemäß Fig. 1
• Fig. 1b einen Schnitt entlang der Linie B-B gemäß Fig. 1a,
• Fig. 2 eine Draufsicht auf ein Ausführungsbeispiel eines Kernaufbaus des beschriebenen Surfbrettes,
• Fig. 2a einen Schnitt entlang der Linie C-C gemäß Fig. 2

The invention is described and explained below using an exemplary embodiment and shown graphically in the drawing. Show it:

• 1 is a plan view of the described embodiment in a schematic representation,
• FIG. La shows a section along the line AA according to FIG. 1
• 1b shows a section along the line BB of FIG. 1a,
• 2 is a plan view of an embodiment of a core structure of the surfboard described,
• 2a shows a section along the line CC according to FIG. 2nd

FIGS. 1a and 1b schematically show a structure of the structure of the windsurfing board designed according to the invention, which is significantly reduced in weight by the targeted use of fiber composite materials - such as glass fiber fabrics, aramid fiber plastic or carbon fiber plastic fabrics. In this case, the structure 10 comprises a longitudinal beam 10a with 0 ° unidirectional fabric fibers running essentially in the longitudinal axis on the top and bottom of the board. These unidirectional fiber structures form the upper and lower chords 11, 12 of a so-called shear field girder, the thrust web of which can be designed both as a honeycomb or foam core 15 and as a web structure with a + 45 ° fiber arrangement to the longitudinal axis or as a combination of the two aforementioned solutions. In addition to the bending stresses, this side member also takes over the longitudinal forces that occur.

, Within this carrier are also the force transmission for mast, sword and tail fin. The previously described outer structure or contour of the surfboard forms a torsion bond 13 with a fiber fabric arrangement of ± 45 ° to the longitudinal axis as already mentioned. This torsion bond 13 now encloses a core 15 made of a so-called honeycomb structure or made of foam. However, it can also enclose hollow chambers, which are then separated from one another by webs, so that if the board is damaged, sufficient buoyancy remains to ensure the necessary safety. The foam core 15 can now be composed of foam parts or foams of different densities, depending on the requirements with regard to the impact and shock resistance. The areas of the board which have to absorb increased forces and are subject to particular stress are preferably reinforced with transverse layers 16 of fiber composite fabric laminates running perpendicular to the longitudinal axis.

Fig. 2 shows an embodiment for the construction of a foam core 15, which is made of PVC foam, for example, and the structure of which is then provided at the top and bottom with a + 45 ° diagonal fabric and is designed as a closed torsion bond 13, the longitudinal belt 17 being made of There is 0 ° unidirectional tissue and 14 has 90 ° unidirectional tissue layers as a transverse layer 16 in the area of the shear bandage 14.

This foam core 15 consists of a central bridle 1-7 and a middle piece 14 made of a medium density foam which is embedded in a low density foam 15a. This core thus formed is then enclosed or enclosed by a foam jacket 18 made of shockproof high-density foam.

The manufacture of the windsurf board according to the invention can now take place in various forms. On the one hand, the structure in so-called negative molds can first be built up from the outside in for the upper and lower shells and then both shells can be connected together with the core, the bonding process and the curing process being combined.

Another manufacturing possibility is that shells are prefabricated for the left and right half of the board and then also glued together after installation of the prefabricated side member.

Another method which can be used provides that the prefabricated core, after being provided with the belt structure, is covered with a plastic fiber fabric produced by "knitting" or "knitting" and is then impregnated with synthetic resin and cured. The outer casing can then be formed, for example, by a prefabricated hollow body which, for. B. is designed as a shrink tube and clings to the structure under the influence of temperature during the hardening process.

The torsion structure or the torsion bandage can also be placed around the prefabricated core in a net-like manner using the filament winding method. The core made of plastic can also be provided with an oversize, whereby the required pressing pressure is generated in a closed mold during the curing process.

An extremely favorable surfboard weight has now been achieved by the proposed measures, which has a significantly higher effective buoyancy and thereby enables the sliding base to be achieved even at low speed.

Claims (5)

1. Windsurfing board, characterized in that it is formed from - the forces to be absorbed correspondingly oriented fiber composite laminate layers and, if necessary, a shear bandage (14) made of foam or fiber composite materials. 2. Windsurf board according to claim 1, characterized in that the upper and lower flange (11, 12) of the structure (10) made of unidirectional fiber fabric to form a torsion bandage (13) around a push bandage (14) made of foam or ± 45 ° fiber fabric and one Core structure (15) are shaped. 3. Windsurfing board according to claims 1 and 2, characterized in that perpendicular to the longitudinal axis additional transverse laminate layers (16) are arranged, which together with the unidirectional fiber laminate layers form the upper (11) and lower flange (12). 4. Windsurf board according to one of claims 1 to 3, characterized in that one or more prefabricated foam cores (15) z. B. made of PVC foam at the top and bottom with a + 45 ° diagnostic fabric and as a closed torsion bandage (13). is formed, wherein the forceps (17) consists of 0 ° unidirectional fabric and 90 ° unidirectional fabric layers are arranged as a transverse layer (16) in the region of the pusher bandage (14). 5. Windsurfing board according to one or more of claims 1- 4, characterized in that the foam core (15) consists of a central harness (17) and a middle piece (14) made of medium-density foam, which in a low-density visual space (15a ) is embedded and this structure is surrounded by a foam jacket (18) made of shockproof high density foam.

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