PURPOSE: To easily advance the pressure wave of compressed air into an exhaust gas passage at the backwash of a filter, and separate nearly all particulates from the filter by the impact of the pressure wave.
CONSTITUTION: A honeycomb filter 13 is provided in the course of an exhaust pipe connected to the exhaust manifold of an engine. The filter body 13a of this filter is formed into a cylinder extended in the direction of exhaust gas flow, and plural lines of bulkheads 13b extended in the direction of exhaust gas flow are provided in the filter body in parallel to each other at prescribed intervals in the direction orthogonal to the exhaust gas flow. Plural lines of exhaust gas passages 13c having substantially a rectangular section are formed in the filter body by the bulkheads. The outlet ports of the exhaust gas passages are sealed by outlet side stoppers every other line, and the inlet ports of the exhaust gas passages never sealed by the outlet side stoppers are sealed by inlet side stoppers 13e. A compressed air is sprayed to the filter from the exhaust gas downstream side, whereby the particulates collected by the filter are removed from the filter.
UEMITSU ISAO
DOBASHI KEIICHI
