Joining arrangement for ventilation ducts and the like

Claim 1

A joint for joining the confronting edge portions of panels of ventilation ducts or the like, said joint comprising: a first member including a pair of overlying legs defining a flat, U-shaped cross section telescopically receiving therein one panel edge to be joined, one leg of said pair of legs comprising a portion extending angularly from said one leg and forming a reverse-fold defining a raised edge, said reverse-fold continuing in a panel portion overlying said one leg forming the raised edge and comprising a free-edged panel extending beyond said one leg; and a second member including a substantially flat, S-shaped cross section including a socket portion receiving another panel edge to be joined, said free-edged panel of the first member extending into a second socket portion of said S-shaped cross section, said second socket portion of the S-shaped cross section continuing in a reverse-folded stiffening portion extending outwardly from said S-shaped cross section, said stiffening portion including a laterally projecting portion extending away from the stiffening portion and overlying the U-shaped cross section and including a depending hook portion snappingly-engaged onto said raised edge.