Surface aerator

The utility model discloses a surface aerator which comprises a foundation, a driving motor and a speed reducer, the driving motor and the speed reducer are located above the foundation, the output end of the driving motor is connected with the input end of the speed reducer through a coupler, the output end of the speed reducer is connected with a rotating shaft, and an inverted-umbrella-shaped impeller and a stirring impeller are fixedly installed on the rotating shaft. The inverted-umbrella-shaped impeller comprises an impeller shaft sleeve fixed to the outer side of the rotating shaft, a plurality of straight blades welded to the impeller shaft sleeve and a plurality of conical plates arranged at equal angles, the adjacent straight blades are connected through the conical plates, and aplurality of tooth-shaped protrusions are arranged on the outer edges of the straight blades. The aeration device has the beneficial effects that the water flow diffusion area can be increased, and the aeration effect is enh