Self-evacuating vacuum cleaner

A dust collector, comprising a a motor, a of the vane wheel the electric suction for (74) and a of the box body is through inlet pipe is wet tissue and pump according wherein a box body (32) is (104). The dust collector further comprises cutting machine and manual control module (144), wherein a liquid level of the box body is too high closing motor automatic. Further, the user can manual control the automatic closer, a annular inner side of the small pump mechanically the box body (32). The box body is provided with a gap sleeve, which is connected with the pump liquid, a valve selectively is, is provided with a pressure difference of liquid in the gap sleeve, thus priming pump.