Watercraft which can be propelled by human power

Abstract

The watercraft includes: an open rigid frame having a concavity, two rigid oblong floats ( 11, 12 ) respectively fastened at the two ends of the frame, extending transversely with respect to the frame, on either side thereof, so as to offer a user a grip for his hands, and seat element ( 7 ) serving to support a user positioned astride. The frame is tubular and provided in its lower part with at least one water access orifice ( 8, 9, 10 ) and in its upper part with at least one vent (E 1 , E 2 ) enabling the frame to fill at least partially with water and act as a ballast.

1 . A watercraft which can be propelled by human power comprising:
 a rigid frame ( 30 ) having a shape defining a concavity,   two rigid oblong floats ( 11 ,  12 ) respectively fastened to the two ends of the frame, these two floats ( 11 ,  12 ) extending transversely in relation to said frame, on either side thereof, so as to offer a user a grip for his hands, and   seat means ( 7 ) serving to support a user positioned astride in said concavity,   
     characterized in that said frame is tubular and comprises, in its lower portion, at least one water access orifice ( 8 ,  9 ,  10 ) and in its upper portion, at least one air passage orifice or vent (E 1 , E 2 ) provided such that, when the craft is in the water, the frame fills at least partially with water and the water contained inside the frame acts as a ballast. 
   
   
       2 . The watercraft according to  claim 1 , characterized in that the aforementioned vent (E 1 , E 2 ) is provided with sealing means (O 1 , O 2 ) so as to allow the user to control the amount of water inside the frame. 
   
   
       3 . The watercraft according to  claim 1 , characterized in that the frame is equipped with propulsion means using the rotational movements of the frame. 
   
   
       4 . The watercraft according to  claim 3 , characterized in that the aforementioned propulsion means consist of a flipper ( 23 ) or flexible fin, elastically deformable, fastened on one of the posts of the frame, essentially at mid-height thereof, this flipper ( 23 ) extending toward the outside of the frame. 
   
   
       5 . The watercraft according to  claim 4 , characterized in that the aforementioned flipper ( 23 ) extends in a plane passing through the axis of rotation (R) of the frame or in the vicinity of said axis. 
   
   
       6 . The watercraft according to  claim 4 , characterized in that the aforementioned flipper ( 23 ) has a cardioid shape. 
   
   
       7 . The watercraft according to  claim 4 , characterized in that the posts of the aforementioned frame are provided with means allowing a disconnectable assembly of said flipper ( 23 ). 
   
   
       8 . The watercraft according to  claim 1 , characterized in that the central portion of said frame comprises a zone covered with a flexible lining ( 7 ) in the form of a semi-cylindrical shell serving as a seat. 
   
   
       9 . The watercraft according to  claim 8 , characterized in that said lining ( 7 ) is made of a closed-cell expanded plastic material. 
   
   
       10 . The watercraft according to  claim 1 , characterized in that said frame is made in a light material such as a plastic. 
   
   
       11 . The watercraft according to  claim 1 , characterized in that it comprises at least one flipper rotatingly mounted on the rear portion of the frame ( 30 ) as well as at least one actuating lever ( 52 ,  53 ) rotatingly mounted on the front portion of the frame ( 30 ) as well as transmission means making it possible to cause a flapping movement of the flipper ( 58 ,  59 ) under the effect of an alternating tilting movement of the drive lever ( 52 ,  53 ). 
   
   
       12 . The watercraft according to  claim 11 , characterized in that it comprises two levers ( 52 ,  53 ) articulated on the front portion of the frame ( 30 ), and in that the flapping movements of the flipper ( 58 ,  59 ) are caused by the alternating tilting of the two levers ( 52 ,  53 ). 
   
   
       13 . The watercraft according to  claim 11 , characterized in that it comprises two flippers ( 58 ,  59 ) rotatingly mounted on the rear portion of the frame ( 30 ) as well as two actuating levers ( 52 ,  53 ) articulated under the front portion of said frame ( 30 ), each lever ( 52 ,  53 ) being coupled to a corresponding flipper ( 58 ,  59 ) by an independent transmission means. 
   
   
       14 . The watercraft according to  claim 11 , characterized in that said transmission means are of the cable/drum and return wheel type. 
   
   
       15 . The watercraft according to  claim 11 , characterized in that said flippers ( 58 ,  59 ) and said levers ( 52 ,  53 ) are rotatingly mounted on a rigid structure ( 51 ) housed inside the frame ( 30 ). 
   
   
       16 . The watercraft according to  claim 11 , characterized in that it comprises an additional actuating lever ( 70 ,  71 ) integral with said flipper or said flippers ( 58 ,  59 ). 
   
   
       17 . The watercraft according to  claim 15 , characterized in that said rigid structure ( 51 ) also supports said transmission means and is fastened on the frame using disconnectable fastening means so as to be able to assemble and disassemble said rigid structure ( 51 ) with its equipment like a cassette. 
   
   
       18 . The watercraft according to  claim 11 , characterized in that the tubular frame ( 30 ) is made in two half-shells ( 32 ,  33 ) which can be assembled together at their lateral edges, and in that said rigid structure ( 51 ) engages between said lateral edges for its fastening on the frame. 
   
   
       19 . The watercraft according to  claim 11 , characterized in that said actuating levers ( 52 ,  53 ) have a bent shape and engage in indentations ( 39 ,  40 ) provided in said floats. 
   
   
       20 . The watercraft according to  claim 11 , characterized in that the transmission means comprise a disengageable connection making it possible to adjust the travel of the lever(s) ( 52 ,  53 ) in relation to the travel of the flipper(s) ( 58 ,  59 ). 
   
   
       21 . The watercraft according to  claim 1 , characterized in that the frame ( 30 ) is provided with a foldable support foot and/or rolling means to ensure the stability of the craft on the ground and/or of any movement thereof on the ground. 
   
   
       22 . The watercraft according to  claim 11 , characterized in that the ends of the frame ( 30 ) engage in cavities provided in the floats ( 35 ,  36 ).