EXHAUST GAS PURIFYING SYSTEM FOR INTERNAL COMBUSTION ENGINE AND SOOT FILTER REGENERATING METHOD

摘要

An exhaust gas purifying system (1) for an engine (2) is provided with a soot filter in a PM filter device (10) for capturing PM contained in exhaust gas; a regeneration execution determining means in a control device (9), determining whether or not the soot filter is to be regenerated; an air-cooled after cooler (4) for cooling intake air supercharged by an exhaust turbine supercharger (3); a cooling fan (5) for supplying cooling air to the after cooler (4); and a fan speed control means for forcible regeneration, provided in the control device (9) and reducing the speed of the cooling fan (5) when the regeneration execution determining means determines that the soot filter is to be regenerated.