Patent ID: 8236084

Claim:
A particulate filter comprising a ceramic cylindrical filter body having a central longitudinal axis, the filter body comprising a plurality of adjacent troughs circumferentially arranged around the longitudinal axis, each trough having an inner surface and an outer surface, each trough comprising a pair of walls extending generally radially, each trough having an open end and a closed end disposed opposite the open end, the closed end being disposed radially inward of the open end; and wherein the walls of each trough have rounded surfaces proximate to their open end and rounded surfaces proximate to their closed end and wherein the rounded surfaces proximate to said open end round toward adjacent troughs, such that adjacent trough walls converge to form a common radially extending wall segment between the outermost part of rounded surfaces proximate to said open end and an outer radius of the troughs; and wherein the troughs comprise first and second subsets of troughs, the closed ends of the troughs of the first subset being disposed farther away from the central longitudinal axis than the closed ends of the troughs of the second subset.