Patent ID: 6874642

Claim:
A filter system for filtering a fluid comprising: a cylindrical case comprising (i) a cylindrical sidewall extending about a central axis and having closed axial ends, and (ii) an inlet and an outlet; and a filter element in the form of a tubular cylinder axially positioned within said case such that axial ends of said filter element are respectively capped by said closed axial ends and the interior of the case is partitioned by said filter element into an inner radial part and an outer radial part; said filter element comprising an absorbent tissue paper material in sheet form compactly wound to form inner winding turns therein and to form said tubular cylinder, said inner winding turns exhibiting a contour which prevents the inner winding turns from unraveling inward, said filter element being devoid of a central core, said inlet communicating with said outer radial part and said outlet communicating with said inner radial part such that fluid to be filtered flows in a centripetal direction from said outer radial part across said filter element and into said inner radial part.