Cloth bag dust collector is a kind of dry dust filtering device. Filter material to use after a period of time, due to the screen, collision, stranding, diffusion, electrostatic effect, such as a layer of dust accumulation on the surface of filter bag, at the beginning of the dust layer is called layer, after the movement process, early become the main filter to filter material layer, depending on the role of the first layer, large mesh filter material can also get higher filtration efficiency. As in the accumulation of dust on the surface of the filter material, filter efficiency and resistance are corresponding increase, when the pressure difference on both sides of the filter material is very big, can put some tiny dust particles are attached to the filter material has been squeezed in the past, the dust collector efficiency decline. In addition, the resistance is too high will make the system of dust control of air volume dropped significantly. Therefore, filter resistance after reaching a certain value, the soot cleaning in time. Soot cleaning could not be broken when the first layer, in order to avoid efficiency decline.