| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust emission control device capable of homogenizing radial direction distribution of exhaust gas temperature at a time of temperature rise of exhaust gas at a filter front surface and starting combustion of PM almost simultaneously in a filter radial direction in exhaust emission control devices having a filter 3 collecting particulate matter in exhaust gas and an oxidation catalyst carrier 2 arranged on an upstream side thereof. <P>SOLUTION: In the exhaust emission control device, the oxidation catalyst carrier 2 consists of two kinds of base material from a radial direction center part to an outer circumference part. Base material positioned at the outer circumference part has higher heat capacity than base material positioned at the center part. Also, the oxidation catalyst carrier 2 includes many cells through which exhaust gas passes, and cell density of the base material positioned at a radial direction center part is higher than cell density of the base material positioned at the outer circumference part. Moreover, axial direction length of the oxidation catalyst carrier 2 changes from the radial direction center part to the outer circumference part, axial direction length at the center part is longer than axial direction length at the outer circumference part. <P>COPYRIGHT: (C)2007,JPO&INPIT |
