Patent ID: 7591951

Claim:
A fuel filter comprising a filter housing with a fuel inlet and a fuel outlet, a filter element for cleaning fuel situated in said filter housing between the inlet and the outlet, and a water discharge device disposed in said housing, said filter housing including a collecting space for collecting water separated from the fuel, wherein said water discharge device comprises a discharge device housing with a water discharge inlet, a water discharge outlet and a water-permeable membrane arranged in the discharge device housing between the water discharge inlet and outlet, said water-permeable membrane having channel structures which are closed in a sealed manner at their upper ends and open at their lower ends, the channel structures being arranged to receive water molecules which pass through the water-permeable membrane and combine to form water droplets, wherein the open lower ends of the channel structures open into a separated water receiving area of the discharge device housing which is arranged to receive the water droplets discharged from the open lower ends of the channel structures.