초록 ▼

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

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.

대표청구항 ▼

1. A regeneration device for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, comprising:a mechanism which raises a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the mechanism being configured t

1. A regeneration device for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, comprising:a mechanism which raises a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the mechanism being configured to raise the temperature of the exhaust gas to a higher temperature as an amount of particulate matter trapped in the filter decreases;a sensor which detects the amount of particulate matter trapped in the filter;a sensor which detects a temperature of the filter; anda programmable controller programmed to:set a target exhaust gas temperature such that the target exhaust gas temperature is increased as the amount of the particulate matter trapped in the filter decreases;control the mechanism to raise the exhaust gas temperature to the target exhaust gas temperature;cumulatively calculate a time during which the temperature of the filter exceeds a target temperature;determine, when the temperature of the filter does not exceed the target temperature, whether or not the temperature of the filter exceeds a temperature allowing combustion of the particulate matter, which is lower than the target temperature, and calculate an effective regeneration time by multiplying a time during which the temperature of the filter exceeds the temperature allowing combustion of the particulate matter by a predetermined coefficient, combined with the time during which the filter temperature exceeds the target temperature, as an effective regeneration time; andestimate an amount of burned particulate matter in the filter based on the effective regeneration time.2. The regeneration device as defined in claim 1, wherein the controller is further programmed to increase the target exhaust gas temperature more than three times in a step-wise fashion during the regeneration of the filter.3. The regeneration device as defined in claim 1, wherein the controller is further programmed to determine the coefficient based on the temperature of the filter.4. The regeneration device as defined in claim 1, wherein the controller is further programmed to determine the coefficient based on the amount of particulate matter trapped in the filter.5. The regeneration device as defined in claim 1, wherein the diesel engine further comprises a combustion chamber, and the mechanism comprises a fuel injector which injects fuel into the combustion chamber and varies a fuel injection amount and a fuel injection timing in accordance with a signal from the controller.6. A regeneration device for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, comprising:a mechanism which raises a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the mechanism being configured to raise the temperature of the exhaust gas to a higher temperature as an amount of particulate matter trapped in the filter decreases;a sensor which detects the amount of particulate matter trapped in the filter;a sensor which detects a temperature of the filter; anda programmable controller programmed to:set a target exhaust gas temperature such that the target exhaust gas temperature is increased as the amount of the particulate matter trapped in the filter decreases;control the mechanism to raise the exhaust gas temperature to the target exhaust gas temperature;store the amount of particulate matter trapped in the filter at a timing when the mechanism begins to raise the temperature of the exhaust gas as an initial trapped amount;cumulatively calculate a time during which the temperature of the filter exceeds a target temperature as an effective regeneration time;calculate an amount of burned particulate matter based on the effective regeneration time;calculate an amount of remaining particulate matter in the filter by subtracting the amount of burned particulate matter from the initial trapped amount; andcontrol the mechanism to stop raising the temperature of the exhaust gas when the amount of remaining particulate matter has decreased to a predetermined target amount.7. A regeneration device for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, comprising:means for raising a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the means being configured to raise the temperature of the exhaust gas to a higher temperature as an amount of particulate matter trapped in the filter decreases;means for detecting the amount of particulate matter trapped in the filter;means for detecting a temperature of the filter;means for setting a target exhaust gas temperature such that the target exhaust gas temperature is increased as the amount of the particulate matter trapped in the filter decreases;means for controlling the temperature raising means to raise the exhaust gas temperature to the target exhaust gas temperature;means for cumulatively calculating a time during which the temperature of the filter exceeds a target temperature;means for determining, when the temperature of the filter does not exceed the target temperature, whether or not the temperature of the filter exceeds a temperature allowing combustion of the particulate matter, which is lower than the target temperature, and calculate an effective regeneration time by multiplying a time during which the temperature of the filter exceeds the temperature allowing combustion of the particulate matter by a predetermined coefficient, combined with the time during which the filter temperature exceeds the target temperature, as an effective regeneration time; andmeans for estimating an amount of burned particulate matter in the filter based on the effective regeneration time.8. A regeneration method for a diesel particulate filter which traps particulate matter contained in an exhaust gas of a diesel engine, the engine comprising a mechanism which raises a temperature of the exhaust gas in order to burn the particulate matter trapped in the filter, the method comprising:controlling the mechanism to raise the temperature of the exhaust gas to a higher temperature as an amount of particulate matter trapped in the filter decreases;detecting the amount of particulate matter trapped in the filter;detecting a temperature of the filter;setting a target exhaust gas temperature such that the target exhaust gas temperature is increased as the amount of the particulate matter trapped in the filter decreases;controlling the temperature raising mechanism to raise the exhaust gas temperature to the target exhaust gas temperature;cumulatively calculating a time during which the temperature of the filter exceeds a target temperature;determining, when the temperature of the filter does not exceed the target temperature, whether or not the temperature of the filter exceeds a temperature allowing combustion of the particulate matter, which is lower than the target temperature, and calculate an effective regeneration time by multiplying a time during which the temperature of the filter exceeds the temperature allowing combustion of the particulate matter by a predetermined coefficient, combined with the time during which the filter temperature exceeds the target temperature, as an effective regeneration time; andestimating an amount of burned particulate matter in the filter based on the effective regeneration time.