| 摘要 |
A filter (10) has a housing (16), a rigid, porous filtering element (54), a primary filter path (80) along the filter element (54), a non-rigid expanding element (56), and discrete annular compartments (78) along the length of the filtering element (54) when a pressure source supplies pressure to the expanding element (56), so that when a solution to be filtered flows through the primary filter path (80), filtrate passes through the rigid filter element (54) and out of the filter and particulate matter is retained on or in the filter element (54). When the filter surface becomes clogged, the incoming solution is bypassed, reduced, or discontinued and the non-rigid expanding element (56) is expanded to first form discrete compartments (78) of filtrate between the expanding element (56) and the filtering element (54) and secondly to force the discrete volumes of filtrate back through the filtering element (54) into the flow path for removal. There are three embodiments used, in all of which suitable inlet and outlet connections and valving structure for switching flow sequentially are provided to control filtering and backflushing cycles. |
