Backwash air filtering silencer

The utility model relates to the technical field of silencers, in particular to a backwashing air filtering silencer. According to the technical scheme, the silencer comprises a filter cylinder and a silencing cylinder which are arranged in a hollow mode, a plurality of sets of filter elements are installed in the filter cylinder, the filter cylinder and the silencing cylinder are communicated through a main ventilation pipe, the silencer further comprises an airflow rotation channel, and the airflow rotation channel is arranged in the silencing cylinder and communicated with the exhaust end of the main ventilation pipe; one end of the switching pipe is communicated with the outside of the silencing barrel, and the other end of the switching pipe is correspondingly communicated with the main ventilation pipe and the airflow rotation channel; and the switching assembly is arranged in the silencing barrel and is used for adjusting the position of the switching pipe so as to adapt to switching of a silencing mod