Patent ID: 7468166

Claim:
An exhaust gas cleaning apparatus for cleaning an exhaust gas emitted from a combustion engine, the apparatus comprising: a stack of plural material layers successively arranged on each other in a stacking direction, wherein the material layers are made of a porous material being permeable to the exhaust gas, wherein the stack has an entry side and an exit side; wherein plural exhaust gas flow channels are defined in the stacking direction between two adjacent material layers in the stack; wherein the exhaust gas flow channels are defined by surfaces of the material layers which have, when viewed in a flow direction of the exhaust gas from the entry side to the exit side, a plurality of concave and convex areas; wherein a first group of exhaust gas flow channels is formed to be open at the entry side of the stack and closed at the exit side thereof; wherein a second group of exhaust gas flow channels is formed to be closed at the entry side of the stack and open at the exit side thereof; wherein exhaust gas flow channels of the first and second groups are alternately arranged in the stacking direction; wherein continuous wave crests and continuous wave troughs are formed by the concave and convex surface areas; and wherein the wave crests and the wave troughs of a first material layer of the stack extend in a first direction, wherein the wave crests and the wave troughs of a second material layer adjacent to the first material layer in the stack extend in a second direction oriented under an angle of more than 10° with respect to the first direction.