| 主权项 |
1. A honeycomb filter comprising:
a plurality of cells through which exhaust gas is to flow and which include exhaust gas introduction cells and exhaust gas emission cells, the exhaust gas introduction cells each having an open end at an exhaust gas introduction side and a plugged end at an exhaust gas emission side, the exhaust gas emission cells each having an open end at the exhaust gas emission side and a plugged end at the exhaust gas introduction side, the exhaust gas introduction cells and the exhaust gas emission cells each hawing a uniform cross sectional shape except for a plugged portion in a cross section perpendicular to a longitudinal direction of the plurality of cells thoroughly from the exhaust gas introduction side to the exhaust gas emission side; porous cell walls defining rims of the plurality of cells, the porous cell walls supporting an SCR catalyst; each of the exhaust gas emission cells being adjacently surrounded fully by the exhaust gas introduction cells across the porous cell walls; the exhaust gas emission cells having an average cross sectional area larger than an average cross sectional area of the exhaust gas introduction cells in the cress section perpendicular to the longitudinal direction of the plurality of cells; the exhaust gas introduction cells have a total volume larger than a total volume of the exhaust gas emission cells; the exhaust gas introduction cells including first exhaust gas introduction cells and second exhaust gas introduction cells, the second exhaust gas introduction cells each having a cross sectional area larger than a cross sectional area of each of the first exhaust gas introduction cells in the cross section perpendicular to the longitudinal direction of the plurality of cells; each of the exhaust gas emission cells having a cross sectional area equal to or larger than the cross sectional area of each of the second exhaust gas introduction cells in the cross section perpendicular to the longitudinal direction of the plurality of cells; the exhaust gas introduction cells and the exhaust gas emission cells having, in the cross section perpendicular to the longitudinal direction of the plurality of cells, one of
a first structure such that
the exhaust gas introduction cells and the exhaust gas emission cells each have a polygonal shape, a side forming a cross sectional shape of each of the first exhaust gas introduction cells faces one of the exhaust gas emission cells, a side forming a cross sectional shape of each of the second exhaust as introduction cells faces one of the exhaust gas emission cells, and the side of each of the first exhaust gas introduction cells is longer than the side of each of the second exhaust gas introduction cells, orthe exhaust gas introduction cells and the exhaust gas emission cells each have a polygonal shape, a side forming a cross sectional shape of each of the first exhaust gas introduction cells faces one of the exhaust gas emission cells, and none of sides forming a cross sectional shape of each of the second exhaust gas introduction cells faces the exhaust gas emission cells, anda second structure such that
the exhaust gas introduction cells and the exhaust gas emission cells are each in a shape formed by a curved line,the porous cell walls include
first porous cell walls separating the first exhaust gas introduction cells and the exhaust gas emission cells, andsecond porous cell walls separating the second exhaust gas introduction cells and the exhaust gas emission cells, anda thickness of each of the first porous cell walls is smaller than a thickness of each of the second porous cell walls. |
