| 摘要 |
<p>PURPOSE:To increase a regeneration interval without melt-damaging a filter by providing a particulate capture means in the downstream side from the filter in a flow of exhaust gas, reversed to flow, when the filter is regenerated. CONSTITUTION:The second honeycomb filter 36, in which a honeycomb filter 16 is made small, is provided as a particulate capture means halfway the second bypass passage 34 provided to connect an exhaust passage 12 between the first open-close valve 22 and the honeycomb filter 16 to communicate with a part closed by the second open-close valve 26. Here for filter regeneration, prior to electrification to a heater 18 of the filter 16, the open-close valves 22, 26 are actuated to the second operational position for a predetermined time to allow exhaust gas, introduced to the exhaust passage 12 through the first bypass passage 14, to reversely flow to the filter 16. In this way, a particulate, accumulated in the filter 16, is reduced while collecting the splashed particulate by the second filter 36.</p> |
