Multistage air filtering and dust removing device based on Coanda effect

The utility model relates to a multistage air filtering dust removal device based on a Coanda effect. The multistage air filtering dust removal device comprises a Coanda effect air multiplication airsuction device, a separation device, a large particle collection box, a small particle collection box and a sealing device, the Coanda effect air multiplication air suction device, the separation device, the large particle collection box and the small particle collection box are sealed in the shell through the sealing device. The Coanda effect air multiplication air suction device is connected with the separation module; the bottom of the separation device is connected with the large particle collection module, the upper portion of the separation device is connected with the small particle collection module, the air suction port is formed in the front end of the Coanda effect air multiplication device and communicated with the exterior of the shell to suck in dust-containing waste gas, andthe exhaust pipe is arran