Air quantity regulating device for air-suction type potato seeding unit

The invention relates to an air quantity regulating device for an air-suction type potato seeding unit and belongs to agricultural machinery. The air quantity device is characterized in that the air quantity device is mounted between each seed sucking pipe and the corresponding suction nozzle of the air-suction type potato seeding unit and comprises an inner tube and an outer tube, the sector areaof the bottom ventilation part of the inner tube is 1/3 of the area of the bottom circle of the inner tube, the three ventilation area of the bottom surface of the outer tube is 18.84mm , 56.52mm and 131.88mm which are in geometric progression, the included angle between every two areas is 120 degrees, and corresponding pores in the lateral walls of the inner tube and the outer tube are used for positioning. The air quantity regulating device has the advantages that the device is used to regulate the ventilation area of the seeding unit to allow the ventilation area to increase or decrease in a geometric progression