JP3846452B2 - Engine control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an engine control device provided with a particulate filter in an exhaust passage.
[0002]
[Prior art]
The particulate filter needs to be regenerated by burning and removing the collected particulates when the collected amount of particulates (exhaust particulates) exceeds a predetermined amount. Regarding the regeneration of this filter, an oxidation catalyst is disposed in the exhaust passage upstream of the filter, and the unburnt fuel is supplied to the oxidation catalyst to oxidize and burn, thereby increasing the temperature of the exhaust gas flowing into the filter, It is known to burn filter particulates (see Patent Document 1).
[0003]
In Patent Document 1, the temperature of the exhaust gas flowing into the oxidation catalyst is detected, and when the exhaust gas temperature is equal to or higher than a predetermined value, fuel is injected into the in-cylinder combustion chamber near the top dead center of the compression stroke. Thereafter, unburned fuel is supplied to the oxidation catalyst by performing post-injection in which fuel is injected into the in-cylinder combustion chamber immediately before the exhaust valve is closed. That is, based on the exhaust gas temperature flowing into the oxidation catalyst, it is determined whether or not the oxidation catalyst is in an active state, and when the exhaust gas temperature is low, post-injection for filter regeneration is not performed. .
[0004]
[Patent Document 1]
JP-A-8-42326 [0005]
[Problems to be solved by the invention]
By the way, even when the temperature of the oxidation catalyst is low, if post-injection is executed at a relatively early stage of the expansion stroke after the main injection, the injected fuel burns in the cylinder and the exhaust gas temperature rises. It is possible to regenerate the filter by promoting the activity of the catalyst. Further, the post-injection at the early stage of the expansion stroke prevents the temperature of the oxidation catalyst from decreasing, that is, maintains its active state, improves the oxidative combustion of the unburned fuel, and makes the regeneration of the filter more reliable. it can.
[0006]
However, if the post-injection is executed early in the expansion stroke, the engine is heated excessively by the combustion of the post-injected fuel in the cylinder. Therefore, when the outside air temperature is high, the engine water temperature rises excessively and the engine There is a concern of overheating. Of course, if the cooling performance is increased by increasing the size of the cooling fan for the engine, the problem will be eliminated. However, increasing the cooling performance will increase the cost and increase the size of the cooling device, which is not a good idea.
[0007]
That is, an object of the present invention is to prevent engine overheating when post-injection is executed early in the expansion stroke for regeneration of the filter.
[0008]
Another object of the present invention is to efficiently regenerate the filter while avoiding overheating of the engine.
[0009]
[Means for Solving the Problems]
In the present invention, for the above-described problems, even if the filter is being regenerated, if the engine water temperature tends to rise, post-injection at an early stage of the expansion stroke is suppressed.
[0010]
That is, the invention according to claim 1 is a particulate filter provided in an exhaust passage of an engine,
A collection amount detection means for detecting the particulate collection amount collected by the filter,
An oxidation catalyst provided in the exhaust passage upstream of the filter;
In the expansion stroke after the main injection in which fuel is injected into the in-cylinder combustion chamber of the engine near the top dead center of the compression stroke when the collected amount detected by the collected amount detection means becomes a predetermined value or more. A first post-injection for injecting fuel into the in-cylinder combustion chamber so that the temperature of the exhaust gas flowing into the oxidation catalyst rises; and the unburned fuel is supplied to the oxidation catalyst after the first post-injection. In a control apparatus for an engine, comprising: a regenerating unit that regenerates the filter by burning the particulates collected by the filter by performing second post-injection for injecting fuel into the in-cylinder combustion chamber And a detecting means for detecting a parameter value related to the engine water temperature (cooling water temperature) of the engine,
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post-injection and the second post-injection, the first post-injection It is characterized by suppressing.
[0011]
Accordingly, when the trapped amount of the particulate filter exceeds a predetermined value, the first post-injection is executed, whereby the temperature of the exhaust gas flowing into the oxidation catalyst rises, and the activity of the oxidation catalyst is promoted, or the The oxidation catalyst is maintained in a highly active state, and the unburned fuel supplied by the second post-injection can be efficiently oxidized and burned. Due to the oxidative combustion of the unburned fuel, the temperature of the exhaust gas flowing into the filter increases, and the particulates collected in the filter are efficiently burned and removed.
[0012]
Then, the engine water temperature increases due to the execution of the first post-injection. When the engine water temperature becomes equal to or higher than the first predetermined value, the first post-injection is suppressed (not only the stop of the first post-injection). Therefore, the engine water temperature is prevented from excessively rising due to the high outside air temperature, and the engine overheating is avoided.
[0013]
The second post-injection may be executed in the expansion stroke after the first post-injection or in the subsequent exhaust stroke. Further, the suppression of the first post-injection may be to reduce the injection amount thereafter or to stop the post-injection. Further, the means for detecting the parameter value related to the engine water temperature is not limited to the temperature sensor for detecting the engine water temperature, and any means can be used as long as it can determine the engine water temperature.
[0014]
The invention according to claim 2 is the engine control apparatus according to claim 1,
The regeneration means releases the suppression when it is determined that the engine water temperature has become equal to or lower than a second predetermined value lower than the first predetermined value based on the parameter value after the suppression of the first post-injection. It is characterized by.
[0015]
Therefore, it is advantageous in regenerating the filter without causing overheating of the engine while avoiding hunting in which execution / stop of the first post-injection is frequently repeated.
[0016]
The invention according to claim 3 is the engine control apparatus according to claim 2,
Means for detecting a parameter value related to the outside air temperature;
Threshold correction means for decreasing the first predetermined value and the second predetermined value as the outside air temperature increases based on a parameter value related to the outside air temperature is provided.
[0017]
That is, the higher the outside air temperature, the higher the engine water temperature due to the first post-injection, and the more likely it is to overheat. Therefore, in the present invention, the first predetermined value is decreased as the outside air temperature increases, and the first post-injection is suppressed early when the engine water temperature starts to rise, so that the overheating can be reliably prevented. It is what. The second predetermined value is also changed in conjunction with the first predetermined value so as to avoid the hunting.
[0018]
The means for detecting the parameter value related to the outside air temperature is not limited to the temperature sensor for detecting the outside air temperature, and may be a temperature sensor for detecting the intake temperature of the engine, and the means is not limited. For example, the level of the outside air temperature can be determined based on the change speed of the parameter value related to the engine water temperature when the first post-injection is executed. That is, with the execution of the first post-injection, the engine water temperature (water temperature determined based on the engine water temperature related parameter value) increases, but the water temperature is a third predetermined value lower than the second predetermined value. It is also possible to measure the time until the second predetermined value is reached after exceeding, and to decrease the first predetermined value and the second predetermined value, assuming that the outside air temperature is higher as the time is shorter.
[0019]
The invention according to claim 4 is the engine control apparatus according to claim 2 or 3, wherein
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post injection and the second post injection, the first post injection is performed. And suppressing the second post-injection when it is determined that the engine water temperature is below a predetermined value intermediate between the first predetermined value and the second predetermined value. And
[0020]
That is, since the second post-injection supplies unburned fuel to the oxidation catalyst, the influence on the engine water temperature is not great. However, when the first post-injection is suppressed, the temperature of the oxidation catalyst is lowered and the activity is increased. The unburnt fuel from the second post-injection may not be effectively used for the regeneration of the filter. Therefore, when it is determined that the engine water temperature has exceeded the first predetermined value, the first post-injection is performed together with the first post-injection. Two injections are also suppressed.
[0021]
On the other hand, when the engine water temperature falls below a predetermined value intermediate between the first predetermined value and the second predetermined value, after a while, the engine water temperature falls below the second predetermined value and the suppression of the first post-injection is released. Is done. Therefore, the suppression of the second post-injection is canceled in advance and unburned fuel is supplied to the oxidation catalyst to cause oxidative combustion, thereby preventing an excessive decrease in the oxidation catalyst temperature and the filter temperature. When the suppression of the first post-injection is released and the temperature of the oxidation catalyst becomes high, full-scale filter regeneration can be resumed promptly.
[0022]
The invention according to claim 5 is the engine control apparatus according to claim 1,
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post-injection and the second post-injection, the first post-injection Only the second post-injection is continued.
[0023]
That is, since the second post-injection supplies unburned fuel to the oxidation catalyst and has little influence on the engine water temperature, the present invention suppresses the first post-injection (not only stopping the first post-injection) The second post-injection is continued even when the first post-injection amount is reduced.). Thus, when the second post-injection is continued and the suppression of the first post-injection is subsequently released and the temperature of the oxidation catalyst becomes high, full-scale filter regeneration by oxidative combustion of unburned fuel is performed. It can be resumed promptly.
[0024]
【The invention's effect】
As described above, according to the first aspect of the present invention, the detection unit that detects the parameter value related to the engine water temperature is provided, and the parameter is reproduced during regeneration of the particulate filter by the first post-injection and the second post-injection. Since the first post-injection is suppressed when it is determined that the engine water temperature is equal to or higher than the first predetermined value based on the value, the engine water temperature rises excessively as the filter is regenerated. It is possible to prevent overheating.
[0025]
According to the invention of claim 2, when it is determined in claim 1 that the engine water temperature has become equal to or lower than a second predetermined value lower than the first predetermined value after the suppression of the first post-injection. Since the suppression is released, it is advantageous to regenerate the filter without causing overheating of the engine while avoiding hunting in which execution and stop of the first post-injection are frequently repeated.
[0026]
According to the invention according to claim 3, when the engine water temperature starts to rise in claim 2, the apparatus includes threshold correction means for decreasing the first predetermined value and the second predetermined value as the outside air temperature increases. The first post-injection can be suppressed early and the overheating can be reliably prevented, and the hunting can also be avoided.
[0027]
According to the invention of claim 4, when it is determined in claim 2 or claim 3 that the engine water temperature has become equal to or higher than the first predetermined value during filter regeneration by the first post-injection and the second post-injection. The second post-injection is suppressed together with the first post-injection, and the second post-injection is suppressed when it is determined that the engine water temperature is below a predetermined value intermediate between the first predetermined value and the second predetermined value. Since the second post-injection is performed unnecessarily and the fuel consumption rate is not deteriorated, when the suppression of the first post-injection is released, the full-scale oxidative combustion of the unburned fuel is performed. Filter regeneration can be resumed promptly.
[0028]
According to a fifth aspect of the present invention, in the first aspect, the engine water temperature exceeds a first predetermined value based on the parameter value during regeneration of the filter by the first post-injection and the second post-injection. When the determination is made, the first post-injection is suppressed and the second post-injection is continued. Therefore, when the suppression of the first post-injection is released and the activity of the oxidation catalyst becomes high, unburned fuel Full-scale filter regeneration by oxidation combustion of can be quickly resumed.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0030]
In the engine control device shown in FIG. 1, 1 is a multi-cylinder diesel engine (only one cylinder is shown in FIG. 1), 2 is its intake passage, and 3 is its exhaust passage. A deep dish combustion chamber 5 is formed on the top surface of the piston 4 of the engine 1. The cylinder head of the engine 1 is provided with a fuel injection valve 7 so that fuel can be directly injected and supplied to the in-cylinder combustion chamber 5 near the top dead center of the compression stroke, and intake air when the engine is cold. A glow plug 8 is provided for warming up.
[0031]
In the intake passage 2, parameter values related to the air cleaner 9, the air flow sensor 10, the blower 11 a of the turbocharger 11, the intercooler 12, the intake throttle valve 13, and the outside air temperature in order from the upstream side to the downstream side. An intake air temperature sensor 14 and an intake air pressure sensor 15 are disposed as means for detecting. In the exhaust passage 3, a turbine 11 b, an oxidation catalyst 16, and a particulate filter 17 of the turbocharger 11 are disposed in order from the upstream side to the downstream side.
[0032]
Exhaust pressure sensors 18 and 19 are disposed upstream and downstream of the particulate filter 17. Both exhaust pressure sensors 18 and 19 constitute particulate collection amount detection means. That is, the particulate amount collected by the particulate filter 17 is detected based on the differential pressure between the exhaust pressures detected by the sensors 18 and 19, and the larger the differential pressure, the larger the collected amount. Can be determined to be large.
[0033]
An exhaust gas recirculation passage in which a portion of the exhaust passage 3 upstream of the turbine 11b and a portion of the intake passage 2 downstream of the intake pressure sensor 15 returns a part of the exhaust gas to the intake system. 21 is connected. Hereinafter, the exhaust gas recirculation is referred to as EGR. In the middle of the EGR passage 21, a negative pressure actuator type EGR valve 22 and a cooler 23 for cooling the exhaust gas with engine coolant are disposed.
[0034]
Fuel is supplied to the fuel injection valve 7 by a fuel supply pipe 25 from a fuel injection pump (not shown) through a common rail (not shown) as pressure accumulating means, and returned to a fuel tank (not shown) by a fuel return pipe 24. It is. 26 is a water temperature sensor that detects the engine water temperature, 27 is a crank angle sensor that detects the engine speed, 28 is a first exhaust gas temperature sensor that detects the temperature of the exhaust gas flowing into the oxidation catalyst 16, and 29 is the particulate filter 17. A second exhaust gas temperature sensor 30 detects the inflowing exhaust gas temperature, and a third exhaust gas temperature sensor 30 detects the exhaust gas temperature flowing out from the particulate filter 17.
[0035]
Thus, the fuel injection valve 7, the glow plug 8, the turbocharger 11 and the EGR valve 22 are controlled by an ECU (Engine Control Unit) 35 using a microcomputer shown in FIG. .
[0036]
The fuel injection control using the fuel injection valve 7 by the ECU 35 includes main injection control for injecting fuel near the top dead center of the compression stroke to generate engine output, and post-injection control for regeneration of the particulate filter 17. There is.
[0037]
The main injection control is basically performed based on the engine speed and the engine load, and further corrected based on the engine water temperature, the intake air temperature, and the like. Regarding the engine load, a detection signal is given to the ECU 35 from an accelerator opening sensor 32 that detects an accelerator opening (a depression amount of an accelerator pedal).
[0038]
Post-injection control, that is, filter regeneration control, is based on the intake temperature sensor 14, exhaust pressure sensors 18, 19, water temperature sensor 26, crank angle sensor 27, exhaust gas temperature sensors 28-29, accelerator opening sensor 32, and the like. Done. For this filter regeneration control, the ECU 35 is provided with a regeneration means 36 and a threshold value correction means 37.
[0039]
(Filter regeneration control)
Hereinafter, the regeneration control of the filter 17 will be specifically described.
[0040]
The regenerating means 36 operates the fuel injection valve 7 to inject fuel so that the temperature of the exhaust gas flowing into the oxidation catalyst 16 rises when the particulate collection amount of the filter 17 exceeds a predetermined value. The first post-injection to be performed and the second post-injection to inject the fuel so that unburned fuel is supplied to the oxidation catalyst 16 are executed.
[0041]
Further, when it is determined that the engine water temperature has become equal to or higher than the first predetermined value during the regeneration of the filter 17, the regenerating unit 36 suppresses the first post injection and the second post injection, and the engine water temperature is set to the first predetermined value. When it is determined that the value is equal to or smaller than a second predetermined value smaller than the value, the suppression of the first post-injection is canceled, and the engine water temperature is intermediate between the first predetermined value and the second predetermined value for suppressing the second post-injection. It is comprised so that it may cancel | release when it determines with it being below the 4th predetermined value.
[0042]
The threshold correction means 37 is configured to decrease the first predetermined value and the second predetermined value as the outside air temperature detected by the intake air temperature sensor 14 increases. That is, as shown in FIG. 3, when the outside air temperature is 0 ° C. or lower, the first predetermined value and the second predetermined value are set to a substantially constant high temperature, but the outside air temperature rises above 0 ° C. Along with this, the first predetermined value and the second predetermined value gradually decrease. However, the temperature difference between the first predetermined value and the second predetermined value is set to be substantially constant regardless of the level of the outside air temperature.
[0043]
FIG. 4 shows the flow of filter regeneration control. In step S1 after the start, a differential pressure ΔP is obtained based on the pressures detected by the exhaust pressure sensors 18 and 19 before and after the particulate filter 17, and in step S2, the particulate collection amount M is calculated based on the differential pressure ΔP. To do. In step S3, the engine water temperature TW detected by the water temperature sensor 26 is read.
[0044]
In subsequent step S4, it is determined whether or not the particulate collection amount M is equal to or greater than a predetermined value α (for example, 10 g per 1 L of filter). If the collected amount M is not equal to or greater than the predetermined value α, the process returns. When the collection amount M is equal to or greater than the predetermined value α, the process proceeds to step S5, and the first post-injection A and the second post-injection B are executed. However, the process proceeds to step S5 on the condition that the temperature of the exhaust gas flowing into the oxidation catalyst 16 is equal to or higher than a predetermined value (temperature at which the oxidation catalyst 16 exhibits a predetermined activity) based on the output of the exhaust gas temperature sensor 28.
[0045]
The injection amount and injection timing of the first post-injection A and the second post-injection B are set with reference to the map based on the engine operating state. FIG. 5 shows an example of the first post-injection amount map, and FIG. 6 shows an example of the second injection amount map. The numerical values given to the respective regions in FIGS. 5 and 6 represent the fuel injection amount per one cylinder, one stroke (one expansion stroke). These maps are basically set so that the post-injection amount increases as the engine load decreases and as the engine speed decreases. This is because the lower the engine load and the lower the engine speed, the lower the exhaust gas temperature due to main injection and the smaller the amount of exhaust gas. However, the second post-injection amount is generally smaller than the first post-injection amount.
[0046]
FIG. 7 shows an example of the first post-injection timing map, and FIG. 8 shows an example of the second injection timing map. 7 and 8 represent the crank angle of ATDC (after compression stroke top dead center). As for the first post-injection timing, in order to increase the exhaust gas temperature while avoiding the influence on the engine output (torque shock), the engine load increases as the engine load increases in the range of ATDC 20 to 35 ° CA (crank angle). The higher the number, the slower. On the other hand, with respect to the second post-injection timing, the engine load becomes higher in the range of ATDC 50 to 120 ° CA so that the post-injected fuel is slightly pyrolyzed and discharged so as to be easily burned by the oxidation catalyst. The higher the number of revolutions, the slower it is set.
[0047]
By executing the first post-injection A, the exhaust gas temperature of the engine 1 rises, and accordingly, the oxidation catalyst 16 rises in temperature and exhibits high activity. Therefore, the unburned fuel supplied to the oxidation catalyst 16 by the second post-injection B efficiently oxidizes and burns, the temperature of the exhaust gas flowing into the filter 17 increases, the particulates ignite and burn, and the filter 17 is regenerated. Will progress.
[0048]
In step S6 following the execution step S5 of the post injections A and B, it is determined whether or not the engine water temperature TW detected by the water temperature sensor 26 is equal to or higher than a first predetermined value. When the engine water temperature TW is not equal to or higher than the first predetermined value, the process proceeds to step S7, where the particulate collection amount M is equal to or lower than the predetermined value β (for example, 1 g per filter 1L), that is, the regeneration of the filter 17 is finished. Determine whether or not. When the regeneration of the filter 17 is finished, the routine proceeds to step S8, where the post-injections A and B are stopped and the routine returns. When the regeneration of the filter 17 is not completed, the process returns to step S5 and the regeneration of the filter 17 by the post injections A and B is continued.
[0049]
On the other hand, when it is determined in step S6 that the engine water temperature is equal to or higher than the first predetermined value, the process proceeds to step S9 to suppress the first post-injection A and the second post-injection B. That is, the post injections A and B are stopped (the post injection amount may be reduced). As a result, as shown in FIG. 9, the engine water temperature that has risen with the execution of the first post-injection A falls before entering the overheat zone.
[0050]
In the subsequent step S10, it is determined whether or not the engine water temperature has dropped below a fourth predetermined value. When the engine water temperature becomes equal to or lower than the fourth predetermined value, the routine proceeds to step S11, where the suppression of the second post-injection B is released (the second post-injection B is restarted). As a result, unburned fuel is supplied to the oxidation catalyst 16, and the oxidation combustion heat prevents the temperature of the oxidation catalyst 16 and the filter 17 from excessively decreasing, or the temperature of the oxidation catalyst 16 and the filter 17 can be increased.
[0051]
In the subsequent step S12, it is determined whether or not the engine coolant temperature TW has dropped below the second predetermined value. When the engine water temperature TW falls below the second predetermined value, the process proceeds to step S13, the suppression of the first post-injection A is canceled (the first post-injection A is restarted), and the process proceeds to step S7. In this case, as described above, since the second post-injection B is restarted in advance and the temperature reduction of the oxidation catalyst 16 and the filter 17 is prevented, the temperature of the oxidation catalyst 16 is increased by the restart of the first post-injection A. When this occurs, efficient oxidative combustion of unburned fuel starts quickly, and the regeneration efficiency of the filter 17 increases.
[0052]
Further, the first predetermined value and the second predetermined value are gradually decreased by the correction by the threshold correction means 37 when the outside air temperature exceeds 0 ° C. Therefore, when the outside air temperature is high, the engine When the water temperature starts to rise, the first post-injection is suppressed early, and the first post-injection A prevents the engine water temperature from rising excessively and causing overheating. In addition, since the second predetermined value also changes while maintaining a substantially constant temperature difference in conjunction with the first predetermined value with respect to the change in the outside air temperature, the hunting in which the execution and stop of the first post-injection A are frequently repeated. Can be avoided.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of an engine control apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram relating to filter regeneration control of the control apparatus.
FIG. 3 is a graph showing a relationship between first and second predetermined values of the regeneration control and an outside air temperature.
FIG. 4 is a flowchart of the reproduction control.
FIG. 5 is a control map diagram of a first post-injection amount in the regeneration control.
FIG. 6 is a control map diagram of a second post-injection amount in the regeneration control.
FIG. 7 is a control map diagram of first post injection timing in the regeneration control.
FIG. 8 is a control map diagram of second post-injection timing in the regeneration control.
FIG. 9 is a graph showing a change over time in engine water temperature in the regeneration control.
[Explanation of symbols]
1 Engine 2 Intake passage 3 Exhaust passage 5 In-cylinder combustion chamber 7 Fuel injection valve 14 Intake temperature sensor 16 Oxidation catalyst 17 Particulate filter 18, 19 Exhaust pressure sensor 26 Water temperature sensor 35 ECU
36 Playback means 37 Threshold correction means

Claims (5)

A particulate filter provided in the exhaust passage of the engine;
A collection amount detection means for detecting the particulate collection amount collected by the filter,
An oxidation catalyst provided in the exhaust passage upstream of the filter;
In the expansion stroke after the main injection in which fuel is injected into the in-cylinder combustion chamber of the engine near the top dead center of the compression stroke when the collected amount detected by the collected amount detection means becomes a predetermined value or more. A first post-injection for injecting fuel into the in-cylinder combustion chamber so that the temperature of the exhaust gas flowing into the oxidation catalyst rises; and the unburned fuel is supplied to the oxidation catalyst after the first post-injection. In a control apparatus for an engine, comprising: a regenerating unit that regenerates the filter by burning the particulates collected by the filter by performing second post-injection for injecting fuel into the in-cylinder combustion chamber And a detecting means for detecting a parameter value related to the engine water temperature of the engine,
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post-injection and the second post-injection, the first post-injection The engine control apparatus characterized by suppressing. In claim 1,
The regeneration means releases the suppression when it is determined that the engine water temperature has become equal to or lower than a second predetermined value lower than the first predetermined value based on the parameter value after the suppression of the first post-injection. An engine control device. In claim 2,
Means for detecting a parameter value related to the outside air temperature;
A control device for an engine, comprising: threshold correction means for decreasing the first predetermined value and the second predetermined value as the outside air temperature increases based on a parameter value related to the outside air temperature. In claim 2 or claim 3,
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post injection and the second post injection, the first post injection is performed. And suppressing the second post-injection when it is determined that the engine water temperature is below a predetermined value intermediate between the first predetermined value and the second predetermined value. Engine control device. In claim 1,
When the regeneration means determines that the engine water temperature has become equal to or higher than a first predetermined value based on the parameter value during regeneration of the filter by the first post injection and the second post injection, Engine control means, wherein only the injection is suppressed and the second post-injection is continued.

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