Abstract: To regenerate a diesel particulate filter (10) which traps particulate matter contained in the exhaust gas of a diesel engine (20), a controller (16) raises the temperature of the exhaust gas through fuel injection control of a fuel injector (23), and thus burns the particulate matter trapped in the filter (10). The controller (16) controls the fuel injector (23) to raise the temperature of the exhaust gas to a higher temperature as the amount of particulate matter trapped in the filter (10) decreases, thereby-realizing effective regeneration while preventing the temperature of the filter (10) from becoming excessively high.

Abstract: A regeneration device for the diesel particulate filter (11) which traps particulates in exhaust gas discharged from a vehicle diesel engine (20) has a condition detecting sensor (12) which detects a condition of the diesel particulate filter, a vehicle speed sensor (27) which detects a vehicle speed, and a controller (40) which stores a map defining a predetermined running region of a diesel engine (20) in which regeneration of the filter (11) is possible. The controller (40) is programmed to modify the diesel engine running point to a running point which maintains the vehicle speed and lies within the predetermined running region.

Abstract: An exhaust gas purifying system for an automotive internal combustion engine. The exhaust gas purifying system includes a particulate filter disposed in an exhaust gas passageway of the engine to collect particulate in exhaust gas flowing through the exhaust gas passageway. The collected particulate is burnt off to be removed by raising a temperature of exhaust gas in a condition in connection with the particulate filter. A plurality of devices are provided for raising the temperature of exhaust gas to be introduced into the particulate filter through the exhaust gas passageway when the collected particulate is burned off to be removed. Additionally, a control unit is configured to select at least one of the devices in accordance with an engine operating region and preferentially operate the selected at least one of the devices for raising the exhaust gas temperature.

Abstract: A particulate filter (41) which traps particulate matter in the exhaust gas of a diesel engine (1), regenerates when a controller (31) performs an exhaust gas increase operation which includes decreasing the opening of an intake throttle (42). The controller (31), during regeneration of the filter (41), determines whether or not the required load of the diesel engine (1) is increasing from an accelerator pedal depression sensor (32) or a fuel injection amount (S3), and prevents output decrease of the diesel engine (1) by interrupting the exhaust gas temperature increase operation when the required load is increasing (S5).

Abstract: An exhaust gas purification system includes a particulate filter, a sensor that detects a filter differential pressure and a controller that controls regeneration of the particulate filter. The controller is programmed to execute a control for burning particulate accumulated on the particulate filter, determine whether regeneration of the particulate filter is completed, detect, in cooperation with the sensor, a filter differential pressure immediately after it is determined that regeneration of the particulate filter is completed, and estimate an ash accumulation amount based on the detected filter differential pressure. An exhaust gas purification method is also provided.

Abstract: This invention relates to regeneration of a filter (41) which traps particulate matter contained in the exhaust gas of a diesel engine (1) for a vehicle. A programmable controller (31) performs filter regeneration appropriately in accordance with the running pattern of the vehicle by calculating a first parameter indicating the frequency with which the diesel engine (1) performs an idling operation over a predetermined time period up to the present (S7), calculating a second parameter indicating the temperature environment of the filter (41) over a predetermined time period up to the present (S3), and determining whether or not the filter (41) can be regenerated completely on the basis of the first parameter and second parameter (S13).

Abstract: A diesel particulate filter (41) which traps particulate matter contained in the exhaust gas of a diesel engine (1) comprises an oxidation catalyst (41A) which exhibits a temperature-raising effect during regeneration of the filter (41). A controller (31) calculates the amount of particulate matter trapped in the filter (41) at the start of regeneration as a first amount, and calculates the amount of particulate matter burned during regeneration of the filter (41) as a second amount (S3, S10, S18). A deterioration factor d of the oxidation catalyst is calculated from the ratio of the second amount and first amount, and a target temperature for the next regeneration of the filter is determined on the basis of this deterioration factor d. Thus deterioration of the oxidation catalyst (41A) is compensated for, and an optimum temperature environment for regenerating the filter (41) is realized.

Abstract: A diesel particulate filter (41) traps particulate matter contained in the exhaust gas of a diesel engine (1) for a vehicle. The filter (41) is regenerated by raising the exhaust gas temperature so that the trapped particulate matter burns. A controller (31) calculates a particulate matter combustion amount PMr during regeneration, and in accordance with increases in the combustion amount PMr, raises the oxygen concentration of the exhaust gas by operating an intake throttle (42) and/or a variable nozzle (24) of a turbocharger (21). As a result, the filter (41) is held at an optimum temperature for regeneration regardless of the residual particulate matter amount, and hence the time required for regeneration can be shortened without damaging the heat resistance performance of the filter (41).

Abstract: To regenerate a diesel particulate filter (10) which traps particulate matter contained in the exhaust gas of a diesel engine (20), a controller (16) raises the temperature of the exhaust gas through fuel injection control of a fuel injector (23), and thus burns the particulate matter trapped in the filter (10). The controller (16) controls the fuel injector (23) to raise the temperature of the exhaust gas to a higher temperature as the amount of particulate matter trapped in the filter (10) decreases, thereby-realizing effective regeneration while preventing the temperature of the filter (10) from becoming excessively high.

Abstract: A regeneration control device, which regenerates a filter (13) for trapping particulate matter in exhaust gas from an engine (1), is disclosed. The filter (13) supports a catalyst which oxidizes unburnt components in the exhaust gas. The regeneration control device has a temperature sensor (14) which detects a filter inlet exhaust gas temperature (Tdpf_in_mea); and a microcomputer (22). The microcomputer (22) is programmed to compute a filter outlet exhaust gas temperature (Tdpf_out_cal), not including temperature rise due to oxidation reaction of unburnt components based on the detected inlet exhaust gas temperature; compute the filter bed temperature (Tbed_cal) based on the detected inlet exhaust gas temperature and computed outlet exhaust gas temperature; compute a temperature rise (?Thc1) due to oxidation reaction of unburnt components; correct the bed temperature based on the computed temperature rise (?Thc1).

Abstract: A diesel engine (1) comprises an exhaust passage (3), and a DPM filter (4) provided on the exhaust passage (3), which traps diesel particulate matter (DPM) contained in the exhaust gas such that the diesel particulate matter accumulates therein. An engine controller (11) starts regeneration processing of the DPM filter (4) by raising the exhaust gas temperature when a regeneration timing of the DPM filter (4) is reached, sets a target exhaust gas temperature during regeneration processing to ensure that the temperature of the DPM filter (4) does not exceed an upper temperature limit of the DPM filter (4), even when the temperature of the DPM filter (4) is raised due to the engine (1) entering an idling condition during the regeneration processing, and controls the exhaust gas temperature to the target exhaust gas temperature.

Abstract: A regeneration control device which regenerates a filter (13) by increasing an exhaust gas temperature to burn exhaust gas particulates trapped in the filter, is disclosed. The filter (13) traps particulate matter in exhaust gas from an engine (1). The regeneration control device suppresses fuel cost-performance impairment due to filter regeneration. The regeneration control device has a load detection sensor (31) which detects an engine load and a microcomputer-based controller (22).

Abstract: A filter differential pressure, which is the difference between the inlet pressure and the outlet pressure of a DPM filter (11), is determined, and switching is performed in accordance with the regeneration condition of the DPM filter (11) between a first trapped DPM amount calculation process for estimating the trapped DPM amount after complete regeneration, in which all of the DPM trapped in the DPM filter (11) is burned, and a second trapped DPM amount calculation process for estimating the trapped DPM amount when a part of the DPM trapped in the DPM filter (11) has been burned away. The trapped DPM amount in the DPM filter (11) is estimated on the basis of the filter differential pressure using one of the first and second trapped DPM amount calculation processes.

Abstract: To regenerate a diesel particulate filter (10) which traps particulate matter contained in the exhaust gas of a diesel engine (20), a controller (16) raises the temperature of the exhaust gas through fuel injection control of a fuel injector (23), and thus burns the particulate matter trapped in the filter (10). The controller (16) cumulatively calculates the time during which the temperature of the filter (10) exceeds a target temperature as an effective regeneration time. By estimating the amount of particulate matter remaining in the filter (10) on the basis of the effective regeneration time, the controller (16) estimates the amount of remaining particulate matter with a high degree of precision and without consuming energy, whereupon regeneration of the filter (10) through fuel injection control ends.

Abstract: A filter (10) which traps particulate matter contained in the exhaust gas of a diesel engine (20) for a vehicle is regenerated by fuel injection control. A controller (16) calculates a representative value of the operating condition of the diesel engine (20) during a latest predetermined time period, and determines the traveling condition of the vehicle on the basis of this representative value. When the representative value corresponds to a highway traveling condition, fuel injection control is performed in accordance with a pattern for burning all of the particulate matter trapped in the filter (10). Under any other conditions, fuel injection control is performed in accordance with another pattern. Hence optimum filter regeneration can be performed depending on the traveling condition of the vehicle.

Abstract: An exhaust passage (2) of a diesel engine (1) is provided with a filter (41) for trapping particulate matter. Regeneration of the filter (41) is divided into first to third phases. In the first phase the filter temperature is raised to the combustion temperature of the particulate matter in a short period of time through control of the exhaust gas temperature. In the second phase, the oxygen concentration of the exhaust gas is held at a predetermined low level while the filter temperature is maintained so as to prevent excessive combustion of particulate matter. In the third phase, wherein the amount of trapped particulate matter has been reduced, the oxygen concentration of the exhaust gas is held at a predetermined high level while the filter temperature is maintained so as to complete the combustion of the trapped particulate matter.

Abstract: An engine exhaust gas purification device is disclosed. The purification device has a filter (13) which traps particulate matter contained in the exhaust gas from an engine; a differential pressure detection sensor (16) which detects a differential pressure of the filter; a sensor (14, 15, 21, 31, 33) which detects an engine running state, and a microcomputer (22). The microcomputer (22) is programmed to compute an estimated ash amount ASH_a of the filter based on the detected differential pressure; compute an oil consumption amount OC_total based on the detected engine running state; compute an ash density DENS_ASH from the oil consumption amount OC_total and estimated ash amount ASH_a, and compute an ash amount ASH of the filter based on the oil consumption amount OC_total and ash density DENS_ASH.

Abstract: A regeneration device for the diesel particulate filter (11) which traps particulates in exhaust gas discharged from a vehicle diesel engine (20) has a condition detecting sensor (12) which detects a condition of the diesel particulate filter, a vehicle speed sensor (27) which detects a vehicle speed, and a controller (40) which stores a map defining a predetermined running region of a diesel engine (20) in which regeneration of the filter (11) is possible. The controller (40) is programmed to modify the diesel engine running point to a running point which maintains the vehicle speed and lies within the predetermined running region.

Abstract: A controller (31) determines whether, during previous regeneration processing of a filter (41), the previous regeneration processing was interrupted or the previous regeneration processing was completed without interruption. An amount of DPM trapped in the filter (41) is estimated on the basis of a pressure loss in the filter (41) during running following uninterrupted completion of the previous regeneration processing in the previous regeneration processing of the filter (41), whereas the amount of DPM trapped in the filter (41) is estimated on the basis of an amount of discharged DPM during running following an interruption in the previous regeneration processing in the course of the previous regeneration processing of the filter (41).

Abstract: A map which defines a relationship of an exhaust gas pressure P2 at the outlet of a filter (13) to a load Q and rotation speed Ne of an engine (1) is prepared, and an exhaust gas pressure P1 at the inlet to the filter (13) is determined from a differential pressure &Dgr;P between the front and rear of the filter and the outlet pressure P2 obtained by referring to the map. The inlet pressure P1 determined in this manner is used to determine an exhaust gas volumetric flow rate Q1, and thus an accurate particulate accumulation SM, which is required to determine the need for regeneration of the filter (13), can be calculated.