The invention relates to the technical field of fans, and discloses an anti-blocking mute
centrifugal fan which comprises a fixing base, a pair of positioning frames, a fan shell, a dustproof frame and an air guide frame, the positioning frames are installed on the fixing base, the fan shell is installed between the positioning frames, the interior of an air outlet of the fan shell is rectangular, a plurality of clamping grooves are formed in the side wall of the dustproof frame, and the clamping grooves are connected with the air guide frame. Positioning base plates are installed in the clamping grooves, and a separating mechanism is arranged between the positioning base plates. Compared with the prior art, when
airflow passes through the dustproof frame, the transmission shaft can be driven to do
circular motion under the action of the fixed fan blades, so that the reset ring at the bottom deforms under the action of the transmission shaft, the
piston rod at the bottom moves, and the position of the
piston rod is changed by means of the movement of the reset ring under the conditions that the
airflow speed changes and the like; and the
piston pipe can stretch out and draw back in the radial direction under the air pressure effect, the transmission ring frame and the cleaning plate can move along with the piston
pipe, the interior of the limiting
sieve plate can be cleaned, and the dust and other blocking conditions are reduced.