Patent ID: 7371321

Claim:
A fluid filtration canister for removing contaminants from a machine fluid, the fluid filtration canister comprising: (a) a hollow housing having an open end and a closed end; (b) filter media disposed within the housing, wherein the filter media is wound around a core disposed within the housing to form a roll having a cylindrical outer surface and a first end formed by successive adjacent edges of the wound filter media, wherein the first end is convex in shape when viewed from the center of the roll; and (c) a base, coupled to the open end of the housing so as to close off the open end of the hollow housing for removably attaching the fluid filtration canister to a machine, the base including: (i) an inlet for receiving fluid from the machine; (ii) an inlet fluid passageway in fluid communication with the inlet and the filter media, at least a portion of the inlet fluid passageway being sized sufficiently small in cross-sectional area to substantially eliminate the flow of fluid due to gravity out of the housing during removal of the fluid filtration canister from the machine when the fluid is at atmospheric pressure and below a predetermined temperature; (iii) an outlet for delivering filtered fluid to the machine; and (iv) an outlet fluid passageway in fluid communication with the outlet and the filter media, at least a port of the outlet fluid passageway also being sized sufficiently small in cross-sectional area to substantially eliminate the flow of fluid due to gravity out of the housing during removal of the fluid filtration canister from the machine when the fluid is at atmospheric pressure and below a predetermined temperature.