Fan capable of increasing air volume

The utility model relates to a fan capable of increasing air volume, which comprises a volute wall, a front side plate and a rear side plate, an air cavity is enclosed by the volute wall, the front side plate and the rear side plate, an air outlet is arranged at one end of the air cavity, an air inlet is arranged on the front side plate, an air inlet ring is arranged in the air inlet, a motor frame is arranged on the rear side plate, and a motor is arranged on one side of the motor frame in the air cavity. A motor is arranged on the front side plate, a wind wheel driven by the motor to rotate is arranged on the motor, a plurality of blades forming a circle in a surrounding mode are arranged on the wind wheel, the blades are in an arc sheet shape, and the blades extend in the direction from the front side plate to the rear side plate. The air guide straight edges obliquely extend from the ends of the blades to the edges close to the center of the wind wheel, and the air guide straight edges are connected with