| 摘要 |
<p>PURPOSE:To make reliability of a filter improvable without generating any smoke by allowing exhaust gas, when one filter is regenerated, to previously pass through the other filter thereafter with one part of the exhaust gas guided to the regenerated filter. CONSTITUTION:In the case of regenerating the first honeycomb filter 16, an open-close valve 24 is actuated so as to close a branch pipe 12, and the other open-close valve 26 is opened. While an open-close valve 28 is actuated to close a little an exhaust passage 10 so that flow resistance of exhaust gas, fluidized in a part of this passage 10, is increased. An open-close valve 32 is opened with another open-close valve 34 closed. Thus by allowing all the exhaust gas, flowing in an exhaust pipe 10, to pass through the second honeycomb filter 18, a particulate in the exhaust gas is removed. The exhaust gas after passing through the honeycomb filter 18 is allowed to partly flow reversely in the direction of the honeycomb filter 16 by a valve opening of the open-close valve 28, and the propagation of firing combustion to the particulate is executed.</p> |
