Month in the Patent Office

A jet nozzle consists of a conical portion which discharges through a rectangular opening formed by an upper plate 2b, side plates 2d, and a semi‐cylindrical lower plate 2e, the surface of which latter the jet tends to follow and is thus deflected down‐wardly, the extent of such deflexion being controlled by a tapered guide flap 3 carried by arms 3b, and movable over the wall 2e by the rotation of crank arms 5. With the flap 3 in its lowest position the jet is deflected vertically downwards. The side plates 2d extend below the end of the plate 2e to prevent atmospheric air from entering sideways and thus causing premature separation of the jet from the surface of the plate 2e.