The front double-door opening mechanism is adopted, which has low wind resistance, good sealing and high efficiency;

The duct adopts a plug-in connection mechanism, which reduces the cumbersome bolt and nut fastening, reduces the labor intensity of workers, and increases the aesthetics of the fan;

The belt automatic tensioning device made of aluminum-magnesium alloy is not deformed and has a long service time, and the inner side of the belt is tightened to reduce the reverse twisting of the belt and greatly increase the use time of the belt;

When the double door of the fan is closed, a rubber sealing device is added, and when multiple fans are started at different times according to the environmental conditions, the outdoor air enters from other stop fans, which greatly increases the working efficiency of the fan, and the air enters through the wet curtain or ventilation window;

The motor is installed reasonably, which not only reduces the wind resistance of the motor to the fan blades, but also makes the fan frame firm by the connection of the motor bottom plate.