Abstract: An exhaust gas purification system with a diesel particulate filter in an exhaust passage of an internal combustion engine. A surface filtration cake layer formation enhancement control or a particulate matter generation amount reduction control is temporarily performed immediately after a forced regeneration treatment on the diesel particulate filter. The system and a method are directed to a particulate matter slip-through phenomenon in which the particulate matter slip-through amount temporarily increases immediately after particulate matter re-combustion in a forced regeneration treatment on the diesel particulate filter. The diesel particulate filter is disposed in the exhaust passage of the internal combustion engine and reduces the total amount of particulate matter emitted to the atmosphere immediately after the particulate matter re-combustion in the forced regeneration treatment on the diesel particulate filter.

Abstract: Exhaust gas of an internal combustion engine is made to pass through an exhaust gas purification device after passing through a pre-oxidation catalyst. When a first temperature of the exhaust gas on an upstream side of the device is lower than a first set temperature, multistage temperature rise injection is performed. When the first temperature becomes the first set temperature or more, post injection is performed in addition to the multistage temperature rise injection, and feedback control of the post injection is executed so that a second temperature of the exhaust gas on a downstream side of the exhaust gas purification device becomes a second set temperature.

Abstract: A high-temperature NOx occlusion reduction type catalyst in which an NOx occlusion material containing an alkali metal is supported, and a low-temperature NOx occlusion reduction type catalyst in which an NOx occlusion material containing an alkaline earth metal is supported, are disposed in series on an upstream side and a downstream side, respectively, of an exhaust gas purification system. An oxidation catalyst is disposed on an upstream side of the high-temperature NOx occlusion reduction type catalyst. The desulfurization of the NOx occlusion reduction type catalysts is facilitated, and the NOx reduction efficiency is improved by the partial oxidation of hydrocarbons in the exhaust gas, while a wide NOx active temperature window is achieved.

Abstract: An exhaust gas purification device 1 includes an exhaust gas processing device 30 provided in an exhaust passage 11 of an internal combustion engine 10, an in-exhaust pipe fuel injection device 24 provided on an upstream side of the exhaust gas processing device 30 to supply fuel to the exhaust gas processing device 30, a NOx sensor 13 provided on a downstream side of the exhaust gas processing device 30, and a control unit 40 that controls combustion in the internal combustion engine 10 based on operating state of the engine 10. To burn and remove PM trapped in the exhaust gas processing device 30, the control unit 40 causes the in-exhaust pipe fuel injection device 24 to supply the fuel to the exhaust gas processing device 30 and stores a detection value from the NOx sensor 13 as a NOx value at an outlet of the engine 10.

Abstract: An exhaust-pipe injection system capable of accurately monitoring a lowered injection pressure generated in a fuel line due to exhaust pipe injection and appropriately perform feedback control for the exhaust injection amount. The exhaust-pipe injection system includes: an exhaust pipe injector that injects fuel to an exhaust pipe of an internal combustion engine; a supply pump that sends a fuel to the exhaust pipe injector via a fuel line; a pressure compensating device provided in the vicinity of the exhaust pipe injector of the fuel line; a fuel pressure sensor provided in the fuel line in an upstream side from the pressure compensating device; and an injection control device that adjusts an injection amount of the exhaust pipe injector based on a monitoring value of the fuel pressure sensor.

Abstract: The present invention pertains to a diesel engine starting device, and achieves stable combustion in a short time when the diesel engine is restarted after stoppage of idling. The diesel engine starting device includes injectors (11) that inject fuel in respective cylinders, and glow plugs (13) that generate heat upon receiving electricity to increase the temperature of the respective cylinders. The diesel engine starting device also includes a starter motor (40) that is driven when the engine starts, and an electronic control unit (ECU) (70) that controls the injectors (11), the glow plugs (13), and the starter motor (40). The ECU (70) stops the piston of the cylinder #1 at the bottom dead center of the compression stroke when the idling is stopped, and starts the electricity feeding to the glow plug (13).

Abstract: A diesel particulate filter (“DPF”) system is provided with temperature sensors at an entrance side and an exit side of a diesel oxidation catalyst, an SV ratio determining device that determines an exhaust gas SV ratio by measuring flow rate of exhaust gas during the DPF forcible regeneration, and an injector diagnosing device including a heat-generation region determining unit to which detection values of the temperature sensors and a determination value of the SV ratio determining device are input to determine whether or not these values are within a theoretical heat-generation region, and an actual injection amount diagnosing unit that diagnoses a decrease amount in an actual injection amount of an exhaust pipe injector, when the detection values of the temperature sensors and the determination value of the SV ratio determining device are within the theoretical heat-generation region.

Abstract: An apparatus for on-board diagnoses of causes of NOX conversion efficiency degradation including: a diagnosis exhaust-pipe fuel injection control unit; a NOX purification device failure specifying unit; and an oxidizing catalyst device failure specifying unit.

Abstract: The exhaust gas purification device includes an exhaust gas post-processing device 30 provided in an exhaust passage 11 of an engine 10, an exhaust injection valve 22, a first catalyst 35, a second catalyst 36 for thermally decomposing fuel injected by the exhaust injection valve 22, an exhaust temperature estimation unit 41 for estimating an exhaust temperature, an engine injection control unit 42 for controlling fuel injection in the engine 10, and regeneration control units 43, 44 for controlling regeneration of the exhaust gas post-processing device 30. When an output value output by the exhaust gas temperature estimation unit 41 is equal to or lower than a threshold during regeneration by the regeneration control units 43, 44, the engine injection control unit 42 controls fuel injection in the engine by performing a multistage injection, which includes a post injection for supplying fuel to the first catalyst 35.

Abstract: An exhaust gas purification system which feeds hydrocarbon by a post-injection under preset conditions to an upstream side of an exhaust gas purification device positioned on the exhaust path of an internal combustion engine, restoring the purifying capacity of the device or purifying the exhaust gas of the device. Under hydrocarbon feed conditions, if a combination of the exhaust gas temperature and exhaust gas flowrate or intake flowrate during control is deemed to be in a misfire region in which hydrocarbon which is fed to the exhaust path no longer combusts in the exhaust gas purification unit, the feed of hydrocarbon is stopped. As a result, it is possible to prevent deposit of hydrocarbon on catalysts or other exhaust gas purification units of the device, making it possible to constantly maintain the temperature of the unit in a controllable state.

Abstract: An engine exhaust gas post-treatment device including a mechanism that can vary opening timing of an exhaust valve, and a control method. A unit is configured to raise a temperature of a part or all of the device to not less than a preset temperature by the mechanism opening the exhaust valve in an exhaust stroke at normal combustion within a range of an afterburning period, and the mechanism feeds the device an exhaust gas whose temperature and pressure are high due to combustion of fuel injected into a cylinder. After the exhaust gas is treated by the device, or when the device is regenerated, the unit adds an unburned fuel component to the exhaust gas by an additional injection of an injector in the cylinder or an injection of a hydrocarbon addition nozzle provided at an exhaust port in accordance with the valve opening timing by the unit.

Abstract: An exhaust gas purification method of a diesel engine, which purifies exhaust gas while suppressing deterioration in drivability and fuel consumption, including when exhaust gas enters a rich reduction state, opening an EGR valve and closing an intake throttle, if a temperature of an NOx occlusion reduction catalyst is at or above a predetermined temperature, and a vehicle having a diesel engine is decelerating from a speed at or above a predetermined speed, and then closing an exhaust throttle provided downstream of the NOx occlusion reduction catalyst and supplying fuel to the NOx occlusion reduction catalyst as a reductant.

Abstract: An NOx purification system and a method for control of the NOx purification system. Two oxidation catalysts are provided upstream of an ammonia solution supply unit, and an in-cylinder fuel injection is so controlled that hydrocarbon in exhaust gas is mainly oxidized by an upstream one of the oxidation catalysts and nitric oxide in the exhaust gas is mainly oxidized by a relatively downstream one of the oxidation catalysts. NOx in the exhaust gas is purified by feeding an ammonia solution to a selective reduction NOx catalyst. The system adjusts to the concentrations of HC, NO and NO2 going to the selective reduction NOx catalyst to proper values so as to purify the NOx efficiently by the selective reduction NOx catalyst, and improve NOx purification performance in a lower temperature range.

Abstract: An exhaust gas purification method, and system. In order from an upstream side of an engine exhaust passage there are provided, a NOx occlusion-reduction catalyst, a hydrocarbon (“HC”) adsorbing member, and a catalyzed diesel particulate filter or oxidation catalyst. During NOx regeneration control, an air-fuel ratio of exhaust gas in terms of excess air factor is taken to be 0.8 to 1.1 when an index temperature representative of the HC-adsorbing member is a first judgment temperature or less, is taken to be 1.0 to 1.1 when the index temperature is between a first judgment temperature and a second judgment temperature, and is taken to be 0.8 to 1.1 when the index temperature is the second judgment temperature or above, causing an outflow of HC to the atmosphere to be reduced.

Abstract: Provided is a fuel injection control device that affords a wider lower limit range of injection amount by a injector for cylinder outside injection, and that can respond to injection requirements over a wider injection amount range. A fuel injection control device includes: a injector 14 for cylinder outside injection that injects fuel into an exhaust passage 12 of an engine 1, in an amount corresponding to a duty ratio; and a control means 15 for controlling the injector 14 for cylinder outside injection, wherein the control means 15 changes an injector driving frequency upon determining the duty ratio, such that the frequency is lowered, stepwise or continuously, as the required injection amount decreases.

Abstract: An exhaust gas purifier including an NOx catalyst of the selective reduction type and a diesel particulate filter arranged in series, and being disposed in an exhaust passage of an internal combustion engine. The purifier includes a passage for urea supply having a hydrolysis catalyst therein and a passage for hydrocarbon supply having an oxidation catalyst therein. The passages are parallel to each other and separate on an upstream side of both the NOx catalyst and the diesel particulate filter. A urea feeder which supplies urea to the passage for urea supply and a hydrocarbon feeder supplies hydrocarbon to the passage for hydrocarbon supply. The injection of an urea is thereby reconciled with the direction injection of hydrocarbon into the exhaust pipe in a compact space.

Abstract: An apparatus for on-board diagnoses of causes of NOx conversion efficiency degradation including: a diagnosis exhaust-pipe fuel injection control unit; a NOx purification device failure specifying unit; and an oxidizing catalyst device failure specifying unit.

Abstract: An exhaust gas purification apparatus including a first exhaust gas treatment member carrying an oxidation catalyst, a three-way catalyst, or a NOx storage reduction catalyst which is used for purifying exhaust gas from an internal combustion engine, a second exhaust gas treatment member having a hydrocarbon (“HC”) storing function disposed on the downstream side of the first exhaust gas treatment member, and a heat dissipating unit disposed between the first exhaust gas treatment member and the second exhaust gas treatment member. An upstream side of the heat dissipating unit is formed into a heat insulating structure, and a further upstream side thereof is formed into a heat retaining structure. Even when an internal combustion engine is accelerating, the exhaust gas flowing into the HC adsorption material can be cooled efficiently and HC can be adsorbed before the temperature of the three-way catalyst or the NOx purification catalyst rises to an HC light-off temperature.

Abstract: A diesel particulate filter (“DPF”) system is provided with temperature sensors at an entrance side and an exit side of a diesel oxidation catalyst, an SV ratio determining device that determines an exhaust gas SV ratio by measuring flow rate of exhaust gas during the DPF forcible regeneration, and an injector diagnosing device including a heat-generation region determining unit to which detection values of the temperature sensors and a determination value of the SV ratio determining device are input to determine whether or not these values are within a theoretical heat-generation region, and an actual injection amount diagnosing unit that diagnoses a decrease amount in an actual injection amount of an exhaust pipe injector, when the detection values of the temperature sensors and the determination value of the SV ratio determining device are within the theoretical heat-generation region.

Abstract: An exhaust-pipe injection system capable of accurately monitoring a lowered injection pressure generated in a fuel line due to exhaust pipe injection and appropriately perform feedback control for the exhaust injection amount. The exhaust-pipe injection system includes: an exhaust pipe injector that injects fuel to an exhaust pipe of an internal combustion engine; a supply pump that sends a fuel to the exhaust pipe injector via a fuel line; a pressure compensating device provided in the vicinity of the exhaust pipe injector of the fuel line; a fuel pressure sensor provided in the fuel line in an upstream side from the pressure compensating device; and an injection control device that adjusts an injection amount of the exhaust pipe injector based on a monitoring value of the fuel pressure sensor.