Water distributor blowdown device under filtering system

The invention discloses a water distributor blowdown device under a filtering system. A water distributor blowdown device under a filtering system comprises a flange base, a water distribution device is installed on the flange base, an upper water distribution cap is connected to the water distribution device, a guide column pipe is arranged in the water distribution device, a water distribution pipe is installed on a guide column, a connecting swing ring is arranged on the water distribution pipe, a pipe body is connected to a pipe body, and a blowdown assembly is installed at one end of the pipe body. A pipe sealing cover is arranged on the sewage discharging assembly, an auxiliary rotating cylinder is fixed in the pipe sealing cover, an inner sleeve rod is installed on the auxiliary rotating cylinder, a piece carrying sleeve is nested outside the inner sleeve rod, and a linkage rod is arranged in the piece carrying sleeve. According to the invention, the sewage discharge assembly mounted at the tail end of