Filtering device and dust collector

The filtering device is used for the dust collector and comprises a filter support, a filtering cylinder arranged on the outer side of the filter support in a sleeving mode, an end cap connected to the lower end of the filtering cylinder and a cover body located on the lower side of the end cap and assembled on the end cap, the end cap is provided with a through end hole, and a middle column corresponding to the end hole is arranged at the lower end of the filter support. Threads are arranged on the peripheral face of the middle column, the end cap is provided with a plurality of clamping pieces, the clamping pieces are provided with ribs, and in the process that the cover body rotates around the middle column in the rotating direction, the cover body pushes the clamping pieces to move towards the middle column, so that the clamping pieces clamp the middle column, and the ribs are embedded into the threads of the middle column. After the middle column is locked by the clamping piece, the ribs embedded in the