Abstract: An exhaust gas heating system for an in-cylinder injection internal combustion engine is disclosed. The system includes a fuel injection device for injecting fuel directly into a combustion chamber of the engine, a spark plug for subjecting fuel, which has been injected as primary fuel from the injection device, to spark ignition such that the primary fuel undergoes primary combustion, an exhaust gas purification device arranged in an exhaust passage of the engine, a purification device temperature computing unit for determining a temperature of the purification device by detecting or estimating the temperature of the purification device, and an additional fuel injection control unit for controlling the injection device when the purification device is found to require activation from the temperature determined by the computing unit, such that an injection of fuel as additional fuel is performed during a flame lasting duration that a flame of the primary combustion remains.

Abstract: An exhaust gas purifying apparatus, which is intended to improve hydrocarbon purifying performance and simplify the after-treatment of adsorbed hydrocarbon, an in which a three way valve 51 is operated under the control of a controller 80 to cause a bypass exhaust gas passage 30 to be communicated with a main exhaust gas passage, so that hydrocarbon in exhaust gas is adsorbed onto an adsorption catalyst 40 when the temperature of a three way catalyst 20 in the main exhaust gas passage 13 is low. When the three way catalyst temperature increases, the bypass exhaust gas passage is shut off from the main exhaust gas passage by the three way valve and the adsorption catalyst is heated by a heater 60, so that the adsorbed hydrocarbon is oxidized at the adsorption catalyst to form a harmless substance.

Abstract: An apparatus for controlling an internal combustion engine having an exhaust purifying catalytic device which absorbs nitrogen oxides contained in exhaust when the engine is in a lean-combustion mode and which deoxidizes the absorbed nitrogen oxides when the engine is in a rich-combustion mode. The engine control apparatus includes an electronic control unit for estimating the amount of purifying capability reducing substances other than nitrogen oxides, which decreases the nitrogen oxide adsorbing ability of the catalytic device, absorbed by the catalytic device, on the basis of the accumulated value of vehicle travel distance, fuel consumption of engine, or intake air amount. The control unit changes the operating condition of engine so that the exhaust gas temperature is increased when it is judged that the estimated adsorption amount has reached a predetermined adsorption amount.

Abstract: In a control apparatus and control method for an internal combustion engine having an exhaust purifying catalytic device for adsorbing nitrogen oxide contained in exhaust gases from the engine, the adsorption state of nitrogen oxide adsorbed by the catalytic device is estimated by an electronic control unit during the lean-combustion driving of the engine. If the catalytic device is saturated with nitrogen oxide, the ignition timing is delayed and the exhaust gas is recirculated to the intake side of the engine with the lean air-fuel ratio kept unchanged. This starts the nitrogen oxide reduced driving mode for deteriorating the combustion state in the engine. At this time, the engine output will not change by a great amount. Further, a reducing atmosphere is created around the catalytic device by unburnt gases, generated due to the deterioration of the combustion state, to deoxidize the adsorbed nitrogen oxide.

Abstract: An engine exhaust emission control system, in which a valve is set at a hydrocarbon adsorbing position to guide exhaust emissions to a bypass line including an adsorbent sieve for adsorbing hydrocarbons during a initial period of engine start-up, and the valve is switched over to a hydrocarbon purging position to guide exhaust emissions to an exhaust line and to divert a part of the exhaust emissions to the bypass line.

Abstract: An exhaust emission control system for a motor vehicle is disposed in an exhaust path, comprises a first catalyst for purifying an exhaust gas during activation of an engine, a second catalyst disposed downstream of the first catalyst and including a lean NOx catalyst, a bypass detouring the first catalyst, a select valve for controlling the amount of exhaust gas to be introduced into the bypass and first catalyst, and a control unit for controlling the select valve and flow of the exhaust gas according to operating status of the engine.

Abstract: A feedback control system for an air-fuel ratio according to the present invention comprises a first oxygen sensor for detecting the oxygen concentration of exhaust gas flowing through a first exhaust pipe of an internal combustion engine, a second oxygen sensor for detecting the oxygen concentration of the exhaust gas passed through an exhaust gas disposer in a common exhaust passage which is connected with both first and second exhaust pipes of the engine, and an electronic control unit for calculating the amount of fuel supply to each cylinder of the engine in accordance with the oxygen concentration of the exhaust gas detected by means of the first oxygen sensor. The electronic control unit contains therein a correction circuit for correcting the amount of fuel supply to that cylinder of the engine which is associated with the second exhaust pipe, in accordance with the oxygen concentration of the exhaust gas detected by means of the second oxygen sensor.

Abstract: Flammable fine particles (particulates) consisting principally of carbon and hydrocarbons are discharged from a diesel engine to its exhaust system. A diesel particulate oxidizer (DPO) is disposed in the exhaust passage for collecting and burning the particulates without allowing the particulates to be discharged directly to the atmosphere. This DPO comprises a ceramic foam with catalyst. When the quantity of particulates collected is above a predetermined value, the DPO will undergo clogging. To prevent this, a high temperature gas containing oxygen is fed to the DPO to burn (regenerate) the collected particulates. In order to accelerate the normal regeneration of the DPO, there are provided a regeneration means for making a retard control of the fuel injection timing in the diesel engine, and a regeneration timing control means for controlling the operation of the regeneration means. Further, there is provided a regeneration timing detection means for detecting the regeneration timing of the DPO.

Abstract: A particulate oxidizer system for a diesel engine comprises a diesel particulate oxidizer (DPO) in the exhaust line to collect and burn particulates in the exhaust. The DPO comprises ceramic foam with a catalyst. When the quantity of particulates in the DPO reaches a predetermined value, high temperature gas containing oxygen is fed to the DPO to burn off (regenerate) the collected particulates. This is achieved by retard control of the injection timing under control of an engine control unit (ECU). A regeneration timing detection means detects the regeneration timing in the DPO. When the quantity of particulates in the DPO falls below a predetermined value, the ECU provides a signal to increase the idling revolution of the engine.