| 摘要 |
A filter arrangement for the exhaust gas of an i.c. engine, for example a Diesel engine, comprises a pair of filter units (16, 17) through one of which the exhaust gas flow passes and through the other of which the engine inlet air flow passes at a given time, and ganged valves (18, 19) which periodically switch the exhaust gas flow from one filter unit to the other, and simultaneously switch the inlet air flow from the said other to the said one filter unit to flow through the latter in the opposite direction to the preceding exhaust gas flow so as to back-flush that filter unit, dislodging deposited solid particulate matter and transporting the dislodged matter into the engine air intake. The operation of valve means may be effected automatically in response to the increase in gas pressure difference across the filter element being traversed by the exhaust gas flow. In another arrangement, instead of two filter units a single rotary filter unit (101 or 120) of drum or disc type is provided, each sectional portion of whose element is traversed first by the exhaust gas flow in one direction and thereafter by the inlet air flow in the opposite direction to dislodge previously-deposited matter. <IMAGE> |
