BACKFLUSHABLE FILTER DEVICE FOR MOLTEN MATERIAL AND DISTRIBUTION UNIT FOR A FILTER DEVICE OF THIS TYPE

摘要

The invention relates to a backflushable filter device for molten material, in particular molten plastic, comprising a housing (1) containing a screen assembly (17), which has at least two screen sections (16) that are separated from one another. The molten material to be filtered is fed to the screen sections (16) by means of at least one distribution unit (3). The latter (3) comprises a control body (9) for the backflushing operation, said body being displaced in a housing (53) that is provided with an inlet (4) for the material to be filtered. In the filtration position, the control body (9) releases the influx of the material to be filtered to all screen sections (16) via connecting channels (23). In a backflushing position, the control body interrupts (9) the influx of the material to be filtered to the screen section (16) that is to be backflushed and links the connecting channel (23) of said screen section (16) with an evacuation channel (28) that is situated in the control body (9). At least the greater part of the periphery of the control body (9) is surrounded by a distribution chamber (7) for material to be filtered, said chamber lying in the housing (53) of the body. The distribution chamber (7) can communicate with all screen sections (16) that are connected to the distribution unit (3) via the connecting channels (23). Guide channels (6) run from the inlet (4) into the regions of the two front faces (61, 62) of the distribution chamber (7). Said front faces (61, 62) lie in the area of the outermost connecting channels (23) or outside the area of all the connecting channels (23). The evacuation channel (28), which runs out of the control body (9), can be brought into fluidic connection with the connecting channel (23) of the respective screen section (16) that is to be backflushed by means of a backflushing channel (27) of at least one projection (14) of the control body (9), said projection bridging the distribution chamber (7).