| 摘要 |
<p>PURPOSE:To remove the clogging of two filters easily and quickly by a method wherein a burner provided on the upstream side of one of the filters is operated only when the engine is operated in a high speed and high load operation zone. CONSTITUTION:Main and auxiliary filters 5 and 6 are arranged in series with each other midway in the exhaust gas passage 4 of an engine 1 and a part of the exhaust passage 4 on the upstream side of the filter 5 and a part of the passage 4 between the filters 5 and 6 are made to communicate with each other through a bypass passage 7. Further, the downstream side of the filter 5 and a part of the exhaust gas passage 4 adjacent to the bypass passage 7 are made to communicate with each other through a communication passage 8. In the ordinary condition, first changeover valves 12 and 13 open a part of the passage 4 on the downstream side of the filter 5 and close the communication passage 8 so that the exhaust gas is discharged into the atmosphere through the passage 4 and the filters 5 and 6 and the particle component of the exhaust gas is collected by the filter 5. On the other hand, when the filter 5 is clogged and the engine shifts to its high speed and high operation zone, the burner 9 is operated to heat and burn the collected particle component of the exhaust gas.</p> |
