Inflatable structure

Abstract

This invention comprises an inflatable structure that is constructed by combining polyhedron structural elements to form more complex geodesic structures. The structural elements are constructed out of straight inflatable tubes, in which the warp of the polyester reinforced fabric is aligned with the principal tube axis, giving it high resistance to bending. The complementary leg ends are connected at the vertices with connectors that comprise a slider and track formation, fixed along the axial angle at the end of each leg. Each leg end is shaped along the natural complimentary lines along the intersecting surfaces of the adjacent structural element. Once assembled, in combination with a fabric cover and groundsheet, the tent is stable and completely freestanding.

I claim:  
     
         1 . A structure comprising: 
 at least three structural units, each of said at least three structural units consisting of three inflatable legs constituting two support legs and an apical leg,    each leg having a free end and an inner end, the inner ends of the three legs being joined at a centrepoint,    the legs being arranged to define a tetrahedron with the three legs lying on three adjacent edges of the tetrahedron and with adjacent pairs of legs lying in planes of three sides of the tetrahedron, and the free ends of the legs defining the fourth side of the tetrahedron;    wherein the apical legs of the units are joined to corresponding legs of the other units at ajoin position.    
     
     
         2 . A structure as claimed in  claim 1  wherein the three legs of each unit are of the same length.  
     
     
         3 . A structure as claimed in  claim 1  wherein two of the legs are of the same length and the third leg is of a different length.  
     
     
         4 . A structure as claimed in  claim 1  wherein each leg is straight.  
     
     
         5 . A structure as claimed in  claim 1  wherein each leg comprises a plastic reinforced by a woven fabric.  
     
     
         6 . A structure as claimed in  claim 5  wherein the warp of the fabric is aligned with the tube axis.  
     
     
         7 . A structure as claimed in  claim 1  wherein a connector unit is provided at the free end of at least one of the legs of each element.  
     
     
         8 . A structure as claimed in  claim 1  wherein the apical legs are all joined directly together.  
     
     
         9 . A structure as claimed in  claim 1  wherein some of the apical legs are connected to other legs through an intermediate beam.  
     
     
         10 . A structure as claimed in  claim 1  wherein the outer ends of the legs are shaped complementary to permit interconnection of the structural elements along the axial angle of the completed structure.