US Patent 7681739 Filter device

A filter device includes a filter housing (10), a filter inlet (12), a filter outlet (14), and a filter element (16). The filter element divides a filter area (18) into two partial areas (20, 22). One partial filter areas is conical in form with the cross-section of that partial area (20) being tapered from the filter inlet (12) to the filter outlet (14). The partial areas are separated from each other by the filter element. This arrangement results in an optimum residence time distribution inside the filter device at a uniform flow rate, which is particularly useful for highly viscous fluids such as polymer melts or similar.