Ventilation fans

The utility model discloses a ventilation fans, including an installation section of thick bamboo and collar, the inner wall lower part annular of an installation section of thick bamboo is equipped with the connecting rod, the inner fixed mounting of connecting rod has the maintenance cover, the lower extreme fixedly connected with ring piece of maintenance cover, the inner circle fixed mountingmotor of ring piece, the fixed mounting of pivot portion of motor has the rotor, the inner wall upper portion fixed mounting ring of an installation section of thick bamboo, the upper end annular of ring is equipped with inserts the post. Loosening the swing arm, leading to the inflection power of over twisting spring, the cardboard card restricts the collar rebound in going into the draw -in groove for cross filter plate and stably install on an installation section of thick bamboo, it is very convenient. 本实用新型公开了种通风风机，包括安装筒和安装环，所述安装筒的内壁下部环形设有连接杆，所述连接杆的内端固定安装有固位套，所述固位套的下端固定连接有环件，所述环件的内圈固定安装电机，所述电机的转轴部固定安装有旋翼，所述安装筒的内壁