| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent that a filtering pore size becomes excessively fine by the collapse of the filter material of a dielectric type filter caused by wind pressure to fasten clogging. SOLUTION: A thin upper layer filter material 3 having charge properties, a rough and stiff middle layer filter material 4 low in charge properties and a lower layer filter material 5 having charge properties and denser than the middle layer filter material 4 are laminated to be held between the metal net- like electrodes 1, 2 of a dielectric type air filter. When the filter materials are charged to allow air to flow, the dust bonded to the upper layer filter material 3 is flocculated to become large and blown off to be caught by the middle filter material 4 and the remaining dust is caught by the lower layer filter material 5. The middle layer filter material 4 is a coarse filter material and, since the bonded dust is made large, the clogging of the filtering pore size of the lower layer filter material 5 is reduced. Since the respective layers act on the catching of dust equally, the local clogging of a specific layer is not generated and clogging life is extended as a whole.</p> |
