Accessory device for enlarging the area of the fin of a surfboard or similar water craft

Abstract

A device that can be attached to a fin of a suf board or similar water craft. The device contains an opening ( 13 ) for receiving the fin ( 3 ). The device is made of elastic material and the area of the device is at least 1.5 times larger than the area of the fin of the surfboard or similar water craft. In one embodiment, the area of the device is 1.5 to 5 times larger that the area of the fin. In another embodiment, the area of the device is about 3 times larger than the area of the fin. The device may be equipped with clamping means for securely fixing the device to the fin.

1 . An accessory device for improving the steerability and increasing the stability of a surfboard or similar water craft said device comprising;
 two side elements connected to each other at their edges; and   an opening surrounded by the side elements for receiving a fin of the surfboard or similar water craft, wherein the device is made of an elastic material and the area of the device is at least 1.5 times larger than the area of the fin and the device comprises deformable extrusions within the device for supporting and holding the device on the fin.   
   
   
       2 . The device as in  claim 1 , wherein the deformable extrusions are in the form of strips that are substantially parallel with the axis of the fin. 
   
   
       3 . The device as in  claim 2 , wherein an outer surface of the device is streamlined by shape and finishing for reducing water resistance. 
   
   
       4 . The device as in  claim 3 , the device comprises clamping means near to the opening for attaching the device to the fin. 
   
   
       5 . The device as in  claim 4 , wherein an end of the device closer to the surfboard is made more rigid than the rest of the device. 
   
   
       6 . A method for increasing the stability of a surfboard or similar water craft, the method comprising increasing an area of the fin by a device attached over the fin, characterized in that the surface area of the device is at least 1.5 times larger than the surface area of the fin. 
   
   
       7 . The method as in  claim 6 , comprising fixing the device removably to the fin by clamping means integrated to the device.