Sheet metal faced slab door

Claim 1

In an insulated sheet metal slab door formed of a rectangular shaped wood frame comprising a pair of vertical stiles joined together at their upper and lower edges by horizontal rails, with the opposite vertical exposed edges of the stiles each having a central internal vertical groove extending the full height thereof, each groove being generally T-shaped in cross-section and having wider side walls perpendicular to the stile edge and opening onto the stile edge to form the head of T-shaped groove, said wider side walls tapering inwardly and terminating in narrower side walls parallel to the wider side walls to form the leg of the T-shaped groove and each of the opposite vertical faces of the frame covered by a metal sheet, which sheets overlap and are secured to the faces of the stiles and rails, and with the opposite edge portions of each of the sheets bent approximately perpendicular to the planes of the sheets to form edge portions overlapping their adjacent stile exposed edges up to the groove head, the improvement comprising: each of the free edges of said edge portions being bent approximately perpendicularly thereto and inwardly relative to their respective stiles to form a flange arranged approximately parallel to the plane of the sheets and loosely inserted within its adjacent stile groove wider side wall, which is roughly parallel to said flanges and with the wider side walls being of sufficient width so that the adjacent flanges are horizontally spaced apart from each other a considerable distance; and with the wider side walls of the grooves being of sufficient depth so that said flanges terminate at a considerable distance away from the bottoms of their respective grooves; each groove having a T-shaped, in cross-section, plastic spacer strip whose leg is inserted between the pair of flanges and having a barbed free end portion extending beyond the pair of flanges towards the bottom Of the groove with the barbed portion interlocking with the narrower side walls of the groove near the bottom thereof, and the head of the strip spanning the space between the flanges and overlapping and in contact with the edge portion areas adjacent to the flanges along substantially the full length of the stiles, with the strip extending substantially the full length of the groove; and upper and lower end cap strips secured to and enclosing said horizontal rails and said vertical stiles; and the strip head holding the said overlapped edge portion areas, and thereby the edge portions, against their stile edges, and holding said flanges between the wider side walls with the barbed leg thus holding and locking the head against outward movement relative to the groove and simultaneously forming a thermal barrier between the flanges, which thermal barrier is sealed by the head contacted against said edge portion areas.