Cabin ventilation device

The utility model discloses a cabin ventilation device which comprises an oxygen sensor, a carbon dioxide sensor, an in-cabin electric control valve, a first in-cabin ball valve, an in-cabin air source, a first in-cabin silencer, a second in-cabin silencer, an in-cabin one-way valve and a second in-cabin ball valve which are arranged in a cabin. The first outboard ball valve, the outboard electric control pneumatic ball valve, the buffer tank, the second outboard ball valve, the negative pressure fan and the industrial control computer are arranged outside the cabin; the oxygen sensor, the carbon dioxide sensor and the in-cabin electric control valve are all electrically connected with the industrial control computer, the in-cabin air source is in pipeline connection with the in-cabin electric control valve through the first in-cabin ball valve, the in-cabin electric control valve is in pipeline connection with the first in-cabin silencer, and the second in-cabin silencer is in pipeline connection with the se