Securing means for minimum weight and volume structural supports

Claim 1

A support structure comprising a plurality of elongated ducts and means extending longitudinally along a longitudinal length of said ducts and interlocking the ducts together to lend structural support to the ducts, said ducts being made of sheet metal, said interlocking means including one of said ducts having an opening extending completely therethrough and having flanges formed from said sheet metal at said opening by having opposing terminated sides of said sheet metal projecting inwardly relative to a center line longitudinally of said one of said ducts to define said opening between said opposing terminated sides, said interlocking means further including another of said ducts having a protrusion with lips thereon, said lips being positioned completely through said opening and interlocking with and completely overlapping said flanges to secure said members together, said lips and protrusion extending the longitudinal length of said another duct and said opening also extending the longitudinal length of said one duct to provide a relative light and structurally supported support structure whereby said elongated ducts can be snapped together to form said support structure, and said flanges and said lips having adhesive placed therebetween to more securely fasten the duct members together and lend additional structural support to the support structure.