PURPOSE: To effectively peel and remove a large amt. of dust adhered to the outside surface of a filter by introducing a large quantity of air from a blasting duct into an air cleaner airtightly held between a stage and a cap plate and removing the dust sticking to the filter.

CONSTITUTION: A support 5 communicating with the blasting duct 10 of a fan 9 is disposed in an air cleaner housing case 4 communicating with a dust discharging duct 19 and an air cleaner stage 7 communicating the support 5 is freely and rotatably mounted thereon. Further, the cap plate 14 for sealing the upper part of the air cleaner W is mounted at the bottom end of a shaft 13 by freely removably and freely rotatably inserting this shaft 13 into a cap 12 covering the upper aperture of the housing case 4. A large amt. of the duct sticking to the air cleaner may be effectively peeled and removed by using this device. The suction capacity of the air cleaner may be increased to the initial capacity by flaring the respectively pleats of the filter.