Patent ID: 8216469
Filing Date: 2012-07-10
Classification: B01D

Abstract:
1. A filter device comprising: a filter housing having a filter inlet for receiving fluid to be filtered and a filter outlet for discharging filtered fluid; a plurality of filter elements received in said filter housing for fluid flow for filtration and for backflushing in both directions therethrough, some of said filter elements can filter while at least one of said filter elements can be backflushed to clean an active filter surface thereof, each of said filter elements having inner filter cavity and an element input opening to said inner filter cavity; a backflusher including a pressure control supporting backflushing of said filter elements, said pressure control having a blocking element selectively blocking and clearing a fluid connection between said filter inlet and said inner filter cavities in said filter elements at said element inlets, said blocking element clearing said fluid connection during filtration and blocking said fluid connection at least one of at a start backflushing and during backflushing, said blocking element including a blocking valve movable by a fluid pressure operated piston that quickly blocks said fluid connection at said one of said filter elements being backflushed creating a hydraulic shock on said one of said filter elements being backflushed and producing a feeding effect increasing removal of dirt on said one of said filter elements being backflushed, said blocking valve having a laterally extending valve plate adjacent said element input of said one of said filter elements being backflushed, said piston extending perpendicularly to a lateral extent of said valve plate, said backflusher having a movable backflushing arm connected by a drive to said discharge opening of said one filter element being backflushed, said blocking element being moved by said drive with said backwashing arm into alignment with said element input of said one filter element being backflushed and connected to said backflushing arm, said drive having a rotatable drive shaft extending along a drive axis, said filter elements being parallel to and arranged concentrically about said drive axis, said blocking element being coupled to said shaft to rotate therewith and being radially spaced from said drive axis, said fluid pressure operated piston being parallel to and laterally spaced from said drive axis; and a longitudinal axis defined by the inner filter cavity of each filter element and extending between said element input thereof and an end-side discharge opening thereof on opposite filter element ends, dirty fluid being dischargeable from each said discharge opening during backflushing, said blocking plate successively blocking each said element input for backflushing.