System for sealing the gap between a surface and a wall edge opposite it

Claim 1

A ground-effect apparatus having a solid frame designed to move above and proximate to a generally horizontal backing surface with the interposition of a pressure fluid cushion system lifting said solid frame out of physical contact engagement with said backing surface and in substantially frictionless, generally horizontal motion relationship with respect thereto, comprising: inner wall means depending from said frame and projecting towards said backing surface to end short thereof, said inner wall means bounding laterally an inner chamber wide open towards said backing surface and bottomed thereby, a compact mass of liquid contained in said inner chamber by said inner wall means, in outright wetting contact with the chamber bottoming extent of said backing surface, which is coextensive with the area of said inner chamber as defined by said inner wall means, outer wall means spaced outwardly from said inner wall means and likewise thereto depending from said frame and projecting towards said backing surface to end short thereof, said outer wall means bounding laterally an outer chamber around said inner chamber, wide open towards said backing surface and bottomed thereby, means for feeding said outer chamber with gaseous fluid at a pressure in excess of the pressure obtaining in said inner chamber, thereby precluding leakage of liquid from said inner chamber into said outer chamber through the intervening peripheral gap between said backing surface and said inner wall means ending short thereof, and means for circulating said liquid along a closed circuit which includes said inner chamber and a hydraulic loop outside the same.