| 摘要 |
<p>PURPOSE:To certainly prevent the dissolving loss of a filter by an exhaust gas flow control means to make exhaust gas to flow in the second direction opposite to an ordinary exhaust gas flow direction when an engine is judged to have turned into a state where particulate fuel can burn itself. CONSTITUTION:In an engine provided with an enlarged diameter part 14 having accommodated a filter 15 at the middle of an exhaust pipe 13, the first bypass pipe 21 is provided to connect a coupling part 22 between an engine 11 and the enlarged diameter part 14 with a coupling part 23 between the enlarged diameter part 14 and a muffler 16. In addition, the second bypass pipe 24 is provided to connect a coupling part 25 between the coupling part 22 and the enlarged diameter part 14 with a coupling part 26 between the coupling part 23 and the muffler 16. When collected particulate fuel is judged to be in a self-burning state, change-over valves 31, 32 provided on the bypass pipes 21, 24 respectively are controlled through a control circuit 51 so that exhaust gas may flow through the bypass pipe 21 from the side of a heater 41 into filter 15, and then discharge through both the second bypass pipe 24 and the muffler 16 into the atmosphere.</p> |
