Structural panel

Claim 1

A structural building panel comprising a plurality of beam elements interlocked together to form an open grid frame, all of said elements having substantially the same cross-sectional configuration including a central web having opposed longitudinally extending edges, at least one longitudinally extending flange integral with each opposed edge of said central web and extending outwardly therefrom substantially perpendicular to said central web, said flanges opposed to each other and projecting outwardly from the same side of said central web, and a retaining lip integral with each projecting edge of said flanges and extending longitudinally therealong substantially parallel to said central web, said lips extending inwardly toward each other over said central web to define a prescribed opening between the innermost edges thereof, an inwardly opening longitudinally extending recess defined between the opposed surfaces of said central web and each of said lips and the inside surface of each of said flanges, said lip defining an outer abutting surface along the length thereof, a cutout defined in opposite corners of the ends of certain of said beam elements defining a projecting tongue in said central web, said cutouts having a length substantially equal to the distance from said central web to the outer abutting surface of said lip and a width substantially equal to the distance between the innermost edge of said lip and the outside surface of said flange so that the projecting end of said tongue is just slidably received through said opening between said lips on another of said beam elements and the ends of said flanges at said cutouts on said certain beam element abuts said outer abutting surface of said lips of said when the projecting end of said tongue substantially abuts said central web of said, an inwardly extending notch defined in opposite sides of said tongue and opening into said cutout, each of said notches spaced from the ends substantially said flanges at said cutout a distance substantailly equal to the thickness of said lip; and, an interlock received through each of said cutouts in said certain beam element and within said recess of said another beam element to lock said certain beam element onto said another beam element, each of said interlocks including an elongatE main body having a generally square cross-sectional shape and slidably received within said recess with that side of said main body facing said tongue abutting the edge of said tongue at said cutout, and a retaining rib integral with said main body at that corner adjacent said notch and extending into said notch so that as a separation force is applied to said beam elements to pull said tongue from between said lips, said retaining lip rotates said main body of said interlock into binding engagement with said tongue and the inside surface of said flange of said another beam element to lock said beam elements together.