FAN Russian patent published in 2017 - IPC F04D29/66 

FIELD: ventilation.

SUBSTANCE: invention includes a housing, an air inlet duct, and a nozzle connected to the housing. The nozzle includes an internal passage for receiving airflow from the housing and an air outlet through which the airflow is emitted from the fan. The internal passage extends around the opening or channel through which air from outside the nozzle is drawn by air emitted from the air outlet. The housing comprises a channel having an air inlet and an air outlet, and also comprises an impeller installed in the channel and allowing airflow through the channel, and an electric motor driving the impeller. The annular guide member extends around the channel for guiding air from the air inlet duct of the housing to the air inlet of the channel. The guide member together with the channel defines an annular noise-suppressing cavity.

EFFECT: improved device reliability.

18 cl, 11 dwg