| 摘要 |
A liquid additive added into an exhaust gas is prevented from adhering to a sensor. An exhaust gas purification device is provided with a sensor which is provided in an exhaust gas passage for an internal combustion engine, an addition valve which is provided near or downstream from the sensor in the flow direction of the exhaust gas and adds the additive into the exhaust gas passage, a catalyst which is provided downstream from the addition valve and receives a supply of the additive from the addition valve, and a pressure difference generating means for making the pressure of the exhaust gas around the sensor higher than the pressure thereof around the addition valve. By generating the pressure difference, the additive is prevented from flowing toward the sensor. |
