Readily detachable self-aligning joint

Claim 1

A structural framework capable of being put together and taken apart repeatedly with little damage to the components thereof comprising: a plurality of frame members, each of said frame members having a fixed projection on the outside thereof near at least one end thereof, and a plurality of joint elements for releasably joining said frame members, each of said joint elements comprising a body having a plurality of cavities therein, each of said cavities having a recess in the periphery thereof which is shaped to receive one of said fixed projections, being shaped to receive an end of one of said frame members but having a cross-section enough greater than the cross-section of said end of said frame member so that said end of frame member, including said fixed projection thereon, can be freely conveyed in and out of said cavity and a plurality of extendable elements, each of said extendable elements being mounted on said body and extendable into one of said cavities to bear against the surface of said end of said frame member in a manner tending to cause said fixed projection to seat into said recess, whereby said structural framework can be put together by positioning the ends of said frame members in said cavities and subsequently extending said extendable elements into said cavities and can be taken apart by withdrawing said extendable elements from said cavities and subsequently removing the ends of said frame member from said cavities.