Patent ID: 8702830

Claim:
A filtering apparatus comprising: first and second adjacent longitudinally extending channels facing one another and separated by a sheet of porous filtering medium to define a filtering unit having first and second longitudinally extending passages fluidly communicating only through said filtering medium; said first and second passages each having an inlet and an outlet at opposite ends thereof with said inlet and said outlet of said first passage being respectively adjacent said inlet and said outlet of said second passage; the filtering medium having edges terminating at the inlet and outlet ends of the channels so that the filter medium does not block the inlet or outlets ends, the inlet and outlet ends being open; said inlet of said first passage and said outlet of said second passage each being provided with a non-blocking flow restrictor to cause a pressure differential across said filtering medium in response to pressurized fluid being presented to said inlets of said first and second passages to promote fluid flow between said first and second passages through said filtering medium while also permitting some fluid flow directly along said first and second passages from said inlets and through said outlets thereof, wherein said first and second channels are not completely blocked by filtering media so as to permit flow directly along said first and second channels if said filtering media becomes blocked.