Ventilation device for closed space

The utility model discloses a ventilation device for a closed space, which relates to the technical field of ventilation, comprises an air pipe, a filter screen for filtering particle impurities is arranged at one end of the inner wall of the air pipe, and is characterized in that a clearing mechanism is arranged outside the air pipe, and the clearing mechanism is used for clearing the particle impurities adsorbed on the outer surface of the filter screen. The cleaning mechanism is arranged, the motor drives the connecting rod to drive the suction nozzles arranged on the collecting box to revolve with the first connecting shaft as the rotating center, meanwhile, the air pump sucks air into the collecting box through the connecting pipe, and particle impurities adsorbed on the outer surface of the filter screen enter the collecting box through the suction nozzles and then are discharged. Therefore, the multiple suction nozzles in the rotating state clean particle impurities adsorbed on the outer surface of the