Patent ID: 9707516
Date: 2017-07-18
CPC Classifications: B01D,F01N,Y02T

Claim:
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; porous cell walls defining rims of the plurality of cells; a round cross sectional shape; a ratio of length of the honeycomb filter to a diameter of the round cross sectional shape of less than 1.0; the exhaust gas introduction cells and the exhaust gas emission cells each having 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; the exhaust gas introduction cells including first exhaust gas introduction cells and second exhaust gas introduction cells, each of the second exhaust gas introduction cells 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; and a total volume of the exhaust gas introduction cells being larger than a total volume of the exhaust gas emission cells, wherein, 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 are each in a shape formed by a curved line, wherein the porous cell walls include wherein a thickness of each of the first porous cell walls is smaller than a thickness of each of the second porous cell walls.