Air perimeter seal for opening

Abstract From the Canadian patent

A seal disposed about the periphery of an opening such as a warehouse door includes an inflatable head bag and a pair of facing inflatable side bags. The head and side bags are each comprised of a plurality of serially coupled, elongated, aligned pleated sections which are separated by apertured baffles for regulating air flow between adjacent pleated sections. A source of air under pressure such as a blower directs air into an upper head bag which, in turn, directs the air flow into the facing side bags via respective duct arrangements coupling the head bag to the side bags. Under pressure the head and, side bags expand toward the center of the opening to enclose in a sealed manner an …