Filter unit for contaminated liquid

摘要

Contaminated liquid medium, e.g. coolant-lubricant used for machining, is passed (20) to a bar screen (24), at the outlet of which is an overflow (26), from which the filtered liquid passes into a clean tank (16). The entry side of the screen is directed downwards and is above the inlet. A dredging chain (34, 36) in the dirty liquid tank (14) has flights which pass by the entry side of the screen and a package of plates (28) in the dirty liquid tank is positioned in the flow path of the liquid medium with its entry side (30) below the screen. Preferably the dirty liquid tank is sealed at the top by a cover with a n enclosed neck (18) for the chain, having it end above the dirty liquid tank.