RECIRCULATING AIR CURTAIN Russian patent published in 2014 - IPC F24F9/00 

FIELD: ventilation.

SUBSTANCE: recirculating air curtain for covering a door opening in a wall of a building with a vestibule includes a ventilation unit having inlet and outlet slot nozzles connected to fan branch pipes, the outlet slot nozzle of which is arranged in the vestibule on the opening side; besides, the outlet nozzle is equipped with a damper kinetically connected to one of the guide blades that have a curved shape and are attached to side walls of the vestibule with possibility of its opening; besides, the blades are made from polymer composite material, and on inner surface of a suction branch pipe from inlet to outlet holes there located are longitudinal curved grooves connected to an annular groove arranged before the inlet hole of the suction branch pipe; besides, the annular groove in its lower part is connected to a pollutant collector; the fan is equipped with a drive with a speed-regulating governor and a temperature control; the suction branch pipe is made in the form of the first elastic section in the suction air flow direction and a stiff section with longitudinal curved grooves and a circular groove on inner surface, which are connected to each other; besides, the elastic section includes an end plate installed at the inlet of the suction branch pipe with possibility of its being moved on rod-like guides and tightly attached to the elastic section.

EFFECT: supply of constant amount of suction air to a fan and optimisation of energy consumption for a fan drive.

1 cl, 3 dwg