Patent attributes
An exhaust gas purification system includes an exhaust purifying element for purifying exhaust gas, and a selective reduction catalyst for promoting reduction of NOx contained in the exhaust gas with a reducing agent. A housing for accommodating the exhaust purifying element includes an outer wall having an accommodating portion. A supply hole is formed on a bottom of the accommodating portion. A pipe that is located inside the housing has a passage through which an interior of the pipe communicates with an exterior of the pipe. The pipe is configured to guide exhaust gas toward the selective reduction catalyst through the passage and the interior of the pipe. The pipe has an end communicating with the supply hole. The injection device of the exhaust gas purification system injects the reducing agent to an interior of the pipe through the supply hole.
