The working principle of micro dust collection is that the motor of the vacuum cleaner rotates at a high speed, sucks air from the suction port, and generates a certain vacuum in the dust box. The dust enters the dust bag in the dust box through the floor brush, nozzle handle, hose and main suction pipe. The dust is left in the dust bag. The filtered air enters the motor through a layer of filter, which is a protective barrier to prevent the dust bag from breaking and the dust is sucked into the motor. The air entering the motor flows out through the motor, Because the carbon brush is constantly worn during the operation of the motor, a filter is added before it flows out of the vacuum cleaner. The finer the filter material is, the cleaner the air can be filtered, but the worse the permeability is. This affects the air volume sucked in by the motor and reduces the dust collection efficiency. But for the user, comfort and cleanliness are the main factors.