Abstract: An exhaust gas purifier for a diesel engine is positioned in the middle of an inlet system for supplying air to a combustion chamber. The exhaust gas purifier includes an HC (hydrocarbon) supply source, and a zeolite catalyst converter, which is activated by the hydrocarbon as a reduction agent to crack NOx (oxides of nitrogen) in the exhaust gas, for thereby purifying the exhaust gas.

Abstract: A Diesel engine exhaust particulate purging apparatus includes sensors (11a, 11b) for detecting the quantity of particulates accumulating in a trap (2), a temperature sensor (10) disposed on the upstream side of the trap for measuring the temperature of exhaust gas flowing into the trap (2), and a control device (12) for controlling current supply to an electric heater (8) and for controlling an open--close operation of a bypass control valve on the basis of output signals from the accumulated quantity detecting means (11a, 11b) and the temperature sensor (10).

Abstract: An exhaust emission purifier for a diesel engine has a particulate trap disposed in the exhaust emission passage of the diesel engine for entrapping particulates contained in exhaust gases emitted from the diesel engine, the particulate trap being housed in a canning container. An electric heater is disposed in the canning container upstream of the particulate trap for heating the exhaust gases to a temperature which is high enough to burn particulates entrapped by the particulate trap. A heat conductor/converter device disposed in the canning container upstream of the electric heater for absorbing heat radiated from the electric heater and discharging the absorbed heat into air flowing from a position upstream of the canning container into the particulate trap. The heat generated by the electric heater is efficiently utilized to heat the air introduced into the particulate trap for reliably and quickly igniting and burning the entrapped particulates.