Fan and cleaning equipment

The utility model discloses a draught fan and discloses a cleaning device with the draught fan, the draught fan comprises a machine shell, a stator assembly and a rotor assembly, the stator assembly is installed in the machine shell, the rotor assembly is rotatably connected with the stator assembly, the rotor assembly is provided with a rotating shaft, and the rotating shaft is fixedly provided with an impeller; the diffuser comprises a first diffusion structure and a shell, the first diffusion structure is arranged between the impeller and the machine shell, the shell comprises a diffusion part and an air guide part, and in the axial direction of the rotating shaft, the distance L2 from the end face, away from the impeller, of the shell to the end face, away from the impeller, of the first diffusion structure is larger than or equal to 1 mm; and the length L1 of the first diffusion structure is less than or equal to three times. The fan and the diffuser meet a certain parameter relation, airflow separation