Duct with air-distributing means

Claim 1

IN A DUCT STRUCTURE, A PAIR OF SPACED PARALLEL LONGITUDINAL WALLS DEFINING AN AIR-DISCHARGING THROAT, A LONGITUDINAL INVERTED CHANNEL DISPOSED BEYOND THE ENDS OF SAID WALLS, SAID CHANNEL COMPRISING A TRANSVERSE WALL HAVING OPENINGS THROUGH WHICH AIR FROM THE THROAT ENTERS THE CHANNEL, AND CHANNEL SIDE WALLS FORMING LOWER EXTENSIONS TO THE MENTIONED PARALLEL WALLS, A FIXED VANE DISPOSED IN SAID CHANNEL BETWEEN AND SPACED FROM THE SIDE WALLS THEREOF TO DIVIDE THE CHANNEL INTO TWO SIDE THROATS EACH DEFINED BETWEEN ONE OF SAID SIDE WALLS OF THE CHANNEL AND AN EDGE OF THE VANE, REMOVABLE SUPPORT MEANS DEPENDING FROM SAID TRANSVERSE WALL TO SUPPORT SAID FIXED VANE, AND AN ANGULARLY ADJUSTABLE VANE DISPOSED IN THE CHANNEL BETWEEN THE FIXED VANE AND THE TRANSVERSE WALL OF THE CHANNEL, SAID ANGULARLY ADJUSTABLE VANE BEING ROTATABLY MOUNTED ON SAID SUPPORT MEANS WHEREBY THE FLOW THROUGH THE TWO SIDE THROATS MAY BE VARIED ACCORDING TO THE ANGULAR ADJUSTMENT OF THE ADJUSTABLE VANE.