Hull for a water craft

Abstract

The present invention relates to a hull for a water craft. More particularly it relates to an inflatable hull with flexible tension members acting in tension, and extending between the gunnels to aid in maintaining the hull shape in operation.

1 . A hull for a water craft, the hull comprising;
 a. an inflatable body comprising two flanks configured to be inflated, each flank forming port and starboard sides meeting together to form a vee shaped hull; the flanks when inflated extending away from each other to terminate at gunnels; and   b. at least one flexible member extending directly between the gunnels, the flexible member being in tension in a beam direction between the gunnels when the body is inflated.   
     
     
         2 . The hull as claimed in  claim 1 , wherein the flexible member is of a size so as to be in tension when the body is inflated. 
     
     
         3 . The hull as claimed in  claim 1 , wherein the flexible member is a strap, cable or planar sheet. 
     
     
         4 . The hull as claimed in  claim 1 , wherein the flexible member cannot act in compression between the port and starboard sides. 
     
     
         5 . The hull as claimed in  claim 3 , wherein the flexible member is a strap. 
     
     
         6 . The hull as claimed in  claim 5 , wherein there are multiple straps spaced apart along the length of the body. 
     
     
         7 . The hull as claimed in  claim 1 , wherein there is an inflatable tube along the length of the gunnels. 
     
     
         8 . The hull as claimed in  claim 1 , wherein the body is relatively stiff when inflated. 
     
     
         9 . The hull as claimed in  claim 1 , wherein the two flanks meet together to form a, or part of a, keel. 
     
     
         10 . The hull as claimed in  claim 9 , wherein the flanks form a depth between the uppers surfaces and where the flanks meet. 
     
     
         11 . The hull as claimed in  claim 10 , wherein the straps extend over the depth. 
     
     
         12 . The hull as claimed in  claim 1 , wherein the hull comprises rigid floor boards configured to be laid upon the straps, when the body is inflated. 
     
     
         13 . The hull as claimed in  claim 12 , wherein the rigid flow boards act in compression, when the straps act in tension. 
     
     
         14 . The hull as claimed in  claim 13 , wherein the straps indirectly compress the floor boards. 
     
     
         15 . The hull as claimed in  claim 9 , wherein the distance between gunnels with the straps in tension is less than the distance between gunnels without the straps. 
     
     
         16 . The hull as claimed in  claim 9 , wherein the straps extend between the port and starboard sides to pull in the flanks of the vee shaped body towards each other. 
     
     
         17 . The hull as claimed in  claim 9 , wherein the vee shaped body flanks are always pushing outwards, or resisting the force of the strap. 
     
     
         18 . The hull as claimed in  claim 1 , wherein the hull is configured to plane. 
     
     
         19 . The hull as claimed in  claim 1 , wherein tension in the flexible member is increased as vertical load on the body and/or keel increases during operation. 
     
     
         20 . A water craft comprising the hull as claimed in  claim 1 .