| 摘要 |
<p>PURPOSE:To improve the renewability of a filter by providing an exhaust air throttle valve, which throttles when the filter is being renewed, more to the downstream of a exhaust system than the filter to seize the exhaust minute particles and by restraining the increase of the internal EGR amount while the throttle valve is throttling. CONSTITUTION:A ceramic filter 14 is provided intermediately in an exhaust passage 13 of a diesel engine E to seize the minute particles in the exhaust gas and an exhaust throttle valve 15 is provided intermediately more to the downstream than the filter 14. A exhaust fine particle purifier is composed of the exhaust throttle valve 15, an inlet throttle valve 10 and a shutter valve 12 forming an exhaust minute particle purifier. Upon regeneration treatment of the intake throttling filter 14 the exhaust gas temperature is raised by heating the inlet air with an electric heater 11 while the exhaust throttle valve 15 is throttled tightly. In addition, increase of EGR amount is restrained, suction of the inlet air is promoted and the oxygen contained in the exhaust gas is secured by keeping the shutter valve 12 half opened and switched to a smaller overlapping inlet/exhaust air amount of the valve timing thus raising the combustibility of the exhaust minute particles.</p> |
