Backflushable filter device for molten material and distribution unit for a filter device of this type

Abstract

A backflushable filtering apparatus for a molten material, particularly for a plastic melt, comprises a housing () in which a sieving arrangement () is provided which includes at least two sieving sections () separated from one another. The melt to be filtered is supplied to the sieving sections () through at least one distributor (). The distributor () includes at least one control body () for backflushing which is moveable within a housing () that is provided with an inlet opening () for the material to be filtered. The control body (), in a filtering position, unblocks the influx of material to be filtered to all sieving sections () through connection channels (). However, in a backflushing position, the control body () interrupts the influx of material to the filtering section () to be backflushed and interconnects the connection channel () of the sieving section () flushed back with a discharge channel () located in the control body (). At least the majority of the circumference of the control body () is surrounded by a distribution space () for the material to be filtered which is situated within its housing (). The distribution space () is connectable through the connection channels () to all sieving sections () in communication with the distributor (). Guiding channels () lead from the inlet opening () to the regions of the two front ends () of the distribution space (). These front ends () are situated in the region of the outermost connection channels () or outside the region of all connection channels (). The discharge channel (), which leads away from the control body (), may be caused to communicate with the connection channel () of the respective sieving section () to be flushed back through a flush back channel () of at least one cross-piece () of the control body () which overbridges the distribution space ().