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　　Here is an introduction to the structure of the negative pressure fan:

　　1. Fan casing: the outer frame and shutters are made of galvanized sheet material and moulded.

　　2. Fan blades: The fan blades are stamped and formed at one time, fastened by forging screws, and are precisely balanced and calibrated by a computer.

　　3. Shutters: The shutter connecting pieces are made of high-strength plastic steel materials and closed tightly and have a long service life. They are mainly dust-proof and rain-proof when the fan is not in use.

　　4. Motor: Use grade 4 high-quality copper wire motors, generally 380V and 220V.

　　5. Belt: Use common rubber triangle belt.

　　6. Diversion hood: divert the air to the exhaust outlet of the fan and exhaust it out of the room.

　　7. Protection net: safety protection net to prevent human hands and foreign objects from entering the fan.

　　8. Pulley: Convert the speed of the motor to a low speed through the large and small pulleys, reducing the fan's operating noise and motor load.

　　The above is the structure of the negative pressure fan. I hope you can understand it. For more information, please log in: www.dlyunfeng.cn