WO1993008074A1

WO1993008074A1 - Spare fin arrangement

Info

Publication number: WO1993008074A1
Application number: PCT/EP1992/002433
Authority: WO
Inventors: Peter Veh; Martin Imdahl
Original assignee: Peter Veh; Martin Imdahl
Priority date: 1991-10-24
Filing date: 1992-10-23
Publication date: 1993-04-29
Also published as: DE4135173C1

Abstract

A spare fin arrangement to be taken along on a sailboard is provided as a replacement for the fin of the sailboard when it has become useless because of damage. The spare fin arrangement comprises two fins (2, 3) which are angularly arranged with respect to each other (V-shape) or essentially parallel to each other. The safety fin can easily be mounted without tools and guarantees an increased safety for the surfer. The fins can be carried in pockets included in the sail without danger of hurting the surfer.

Description

Spare Fin Arrangement

The invention relates to a spare fin arrangement for sailboards.

The fin of a sailboard is exposed to considerable strain during surfing. For instance, a total force of up to more than 500 N acts onto a conventional fin due to the transverse forces transmitted from the sail onto the sailboard. Therefore, it often happens that the fin breaks during surfing or that the fin box splits. A further cause and above all an unavoidable risk is the contact with objects floating on the surface of the water or just below it. Mainly wood and plastic parts form part of these objects. With the velocities surfed in the higher wind range today, an average windsurfer easily reaches 50 km/h (the world record is at beyond 80 km/h) . The contact with the aforementioned objects in the case of such velocities leads to the inevitable loss of the fin and most often also to the loss of the fin box. In this case the manoeuvring of the sailboard is rendered practically impossible. Therefore, in the case of a greater distance from the shore or in the case of corresponding currents, the surfer may get into a life- threatening situation when the fin becomes useless.

FR-A-2,594,785 discloses a spare fin arrangement, wherein a fin which is mounted on a supporting base is fixable to a sailboard by means of a belt arrangement. The fin is vertically adjusted with respect to the underwater hull of the sailboard by means of supports or additionally by a hinge. This spare fin arrangement can even be used when the fin box has become useless. The spare fin arrangement with its supporting base has a bulky design, which makes it difficult to have this arrangement on the sailboard in its unused condition, and when it is in use the free end of the fin is subjected to three great leverages of the water which are laterally applied and^" jeopardize the stability of the fin.

Furthermore, from the German journal "Surf Magazin", October 1991, number 10, page 41, a spare fin is known which is taken along on the sailboard in a mast protector. The spare fin can be inserted into the fin box after removal of the useless fin. Hence, the application of the spare fin requires an intact fin box and it cannot be utilized when the fin box is destroyed.

The invention is based on the problem to provide spare fins for a sailboard, which are stowed, for instance, on the sailboard and if need be, when the conventional fin has become useless, can be fixed to the sailboard easily and without the utilization of tools. The construction is not dependent on the presence of the fin box.

This problem is solved with the features of the claims.

The solution of the invention is based on the idea to provide two fins as replacement for the conventional fin, which can manually and easily be fixed to the sailboard by means of a belt structure if need be.

The advantages of the invention reside in a considerably increased safety for the surfer.

In a preferred embodiment the spare fin arrangement is designed as an angular, V-shaped arrangement of two fins. This arrangement also enables the mounting when the fin box is completely destroyed. Furthermore, the angular arrangement of the fins guarantees an increased stability against the transverse forces occurring during surfing.

In the following, the invention will be described in more detail by means of the drawings.

Fig. 1 shows a cross-section of an angular arrangement of two spare fins on a sailboard in an embodiment according to the invention,

Fig.^' 2 shows a side view of the two spare fins according to Fig. 1,

Fig. 3a shows a top view onto the rear of the sailboard with tension belts of the embodiment of the invention according to Fig. 1,

Fig. 3b shows a perspective view of the embodiment of the invention according to Fig. 3a,

Fig. 3c shows a cross-section of the embodiment of the invention according to Fig. 1 along the direction of the tension belt 6 in Fig. 3a,

Fig. 4 shows an embodiment of a mast protector on a sail of a sailboard with fin pockets in the unfolded condition and separated from the mast according to the invention, Fig. 5 shows the embodiment of the invention according to Fig. 4 in the folded condition and attached to the mast, and

Fig. 6 shows an alternative embodiment of the invention with a parallel arrangement of the two spare fins.

Fig. 1 depicts an arrangement of an embodiment according to the invention with two angularly (V-shape) arranged fins 2, 3 on the underwater hull of a sailboard 1 with a box 19 for the conventional fin which is wrenched off the box. The side views of the fins 2, 3 are depicted in Fig. 2. The fins 2, 3 are preferably releasably connected with each other at their point of contact 4. This can be performed by a belt passed through openings 21 (Fig. 2) , by rings or by fitting them into each other; it is also possible to connect these fins at this point (i.e. the free ends or tips 24) by means of a hinge. The fins can thus be unfolded up to 180°. By means of a belt arrangement 5, which preferably consists of an adjustable belt, the belt is connected with padded plastic plates 9 of each fin 2, 3. Thus the aperture angle between the fins 2, 3 can be adjusted. When tightening the safety fin on the sailboard, the belt arrangement 5 takes up the tension forces. The free ends of the belt arrangement 5 are - preferably used as front tension belts 6 and as rear tension belts 7 for the attachment of the safety fin to the sailboard (cf. Fig. 3). By means of the padded plastic plates 9 arranged at the support ends 23 of the fins 2, 3, the fins 2, 3 are supported against the underwater hull of the sailboard and damage to the skin of the vessel is avoided.

In Figures 3a to 3c, the attachment of the safety fin to the sailboard is depicted in more detail. The front tension belt 6 is, for instance, passed through the rear foot loop 8 (Fig. 3a, b) . Thus, the safety fin is guarded against sliding down towards the rear. The front and rear tension belts 6, 7 are tightened on the sailboard for example by means of a belt buckle so that the arrangement of the safety fin on the sailboard as depicted in Fig. 3c as a cross- section along the direction of the tension belt 6 results.

Instead of angularly arranged spare fins a parallel or inclined arrangement of two spare fins 2, 3 (Fig. 6) is also possible.

According to Fig. 6 (cross-section along the tension belt 6 in Fig. 3a), two parallel spare fins 2, 3 whose distance is adjustable by the belt arrangement 5 are connected with the sailboard 1 by means of tension belts 6, 7 (analogously to the angular spare fins) which are fixed to both ends of the spare fins 2, 3. If the horizontal part of the lower tension belt 5 (see Fig. 6) is shortened, the distance between the tips 24 is reduced so that the two fins are no longer parallel but - more or less - inclined towards each other.

For the case of need (i.e. for the case that the conventional fin becomes useless) the fin can be stowed in a mast protector designed according to the invention (Fig. 4) and taken along while surfing. The mast protector according to the invention consists of two padded parts 10, 11 which comprise pockets 14, 15 for receiving the fins 2, 3 and can be folded upward on both sides of the sail 13 in the area of the tack eyelet from the side of the footrope. Furthermore, the mast protector is provided with a velcro strip tongue 16 laterally fixed to one part 10 and with a padded clamping ring 18 fixed to the top of the other part 11. After the fins 2, 3 and the belt structure 5, 6, 7 have been stowed in the pockets 14, 15, the parts 10, 11 are folded upward around the sail, and fixed around the mast 17 by means of the velcro strip tongue 16 and the clamping ring 18. The longitudinal edges of the parts 10, 11 opposite to the mast 17 can additionally be stiffened by integrated rods, e.g. made of plastics. The mast is fixed to the sailboard 1 by means of the mast base 22.

Fig. 5 depicts the mast protector of the invention according to Fig. 4 in the upward folded condition fixed to the mast 17. The padding of the mast protector according to the invention protects the surfer from injuries and the sailboard from damage when the mast turns over.

Claims

C l a i m s

1. A spare fin arrangement for a sailboard (1) consisting of two fins (2, 3) supported at and projecting from the underwater hull, which is tightenable on the sailboard (1) by means of a belt structure (5, 6, 7) , wherein:

(a) the two fins (2, 3) are arranged in a parallel spaced

10 manner or are inclined towards each other,

(b) a releasable connection of the two fins (2, 3) is provided at their free ends or tips (24) , and

_jc (c) an adjustable belt arrangement (5) is located at the support portions (23) of the two fins (2, 3) which are opposite to the tips (24) of the fins (2, 3), for adjusting the distance of these two portions (23) .

0 2. The spare fin arrangement according to claim 1, wherein the tips (24) of the fins (2, 3) are connected directly forming a V-shaped fin.

3. The spare fin arrangement according to claim 1 or 2, 5 characterized in that the belt arrangement (5) comprises two spaced tension belts (6, 7) transversely running relative to the sailboard.

4. The spare fin arrangement according to claim 3, 0 characterized in that at least one tension belt, preferably the front tension belt (6), is passed through the rear foot loop (8) of the sailboard (1) .

5. The spare fin arrangement according to any one of claims 5 1 to 4, characterized by paddings (9) at the support portions (23) of the fins (2, 3) in order to support them against the underwater hull of the sailboard (1) in the tightened condition..

6. The spare fin arrangement according to any one of claims 1 to 5, characterized in that the spare fins (2, 3) with the belts are placed in a stowage (14, 15) at a mast protector.

7. A mast protector for a sailboard (1) having a stowage for two fins, particularly according to any one of claims l to 6, comprising:

(a) two padded parts (10, 11) which can be folded upward on both sides of the^" sail (13) in the area of the tack eyelet (12) from the side of the foot rope,

(b) two pockets (14, 15) at the inner side of the padded parts (10, 11) for receiving the fins,

(c) a velcro strip tongue (16) fixed to one padded part (10) and laterally connecting the two padded parts (10, 11) around the mast (17) , and

(d) a padded clamping ring (18) fixed to the other padded part (11) and connecting the two padded parts (10, 11) at their top end around the mast (17) .

8. The mast protector according to claim 7, wherein the long sides of the parts (10, 11) opposite to the mast (17) are stiffened by integrated rods.