JP2013108474A - Exhaust emission control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To recycle a filter member only during an appropriate period.SOLUTION: A DPF recycling device includes: a starter switch 17 operated to instruct to stop an engine 3; a DPF recycle switch 16 operated to instruct to recycle a DPF 7 disposed in an exhaust device of the engine 3; an engine stop inhibition control part 28 which inhibits the stop of the engine 3 when the starter switch 17 has been operated; an input determination part 23 for detecting operating conditions of the starter switch 17 and the DPF recycle switch 16 when the engine stop inhibition control part 28 inhibits the stop of the engine 3; an engine stop control part 27 for stopping the driving of the engine when the input determination part 23 detects the operation of the starter switch 17; and first and second DPF recycle control parts 30 and 31 for recycling the DPF 7 by controlling to drive the engine 3 when the input determination part 23 detects the operation of the DPF recycle switch 16.

Description

  The present invention relates to an exhaust device for an internal combustion engine, and relates to an exhaust gas purification device for an internal combustion engine that removes carbon or the like in exhaust gas flowing through the exhaust device.

2. Description of the Related Art Conventionally, an exhaust gas purification apparatus for an internal combustion engine in which a filter member (particulate filter) is disposed in an exhaust pipe in order to remove carbon or the like contained in the exhaust gas of the internal combustion engine is known.
When the filter member continues to collect exhaust particulates and becomes saturated, it is necessary to regenerate the filter function by burning the collected exhaust particulates.

Therefore, in a conventional internal combustion engine exhaust purification device, exhaust pressure sensors are disposed upstream and downstream of the filter member, and when the differential pressure between these exhaust pressure sensors is large, it is determined that exhaust particulates are accumulated on the filter member. Then, by increasing the fuel injection amount for a predetermined time, the exhaust temperature is raised, the exhaust particulates are burned and removed, and the filter member is regenerated. In addition, as a method for estimating the accumulation amount of fine particles without using the exhaust pressure sensor, an accumulation amount per time is set in advance based on the fuel injection amount and the intake air amount, and the operation based on the accumulation amount per time is performed. There is a method for estimating the amount of deposition by calculating how many hours the operation is continued. That is, for example, when the operation with a deposition amount of 5 mm ³ per hour is continued for 10 seconds and then the operation with 20 mm ³ is continued for 10 seconds, the deposition amount is estimated to be 250 mm ³ .

Further, in order to regenerate the filter member, there is a type in which a manual switch is provided and the filter member is regenerated when the manual switch is turned on when the vehicle is stopped.
Further, when such a technique is used, if the ignition key is turned off during the regeneration of the filter member, the exhaust gas does not flow to the filter member, so the heat accumulated in the filter member loses its escape and becomes high temperature. There was a problem that the filter member deteriorated its durability.
In view of such a problem, in the exhaust gas purification apparatus for an internal combustion engine disclosed in Patent Document 1, when it is detected that the ignition key is turned off, the internal combustion engine is prohibited from being stopped until the temperature of the filter member decreases. The filter member regeneration process is continued.

JP 2005-83306 A

By the way, in the exhaust gas purification apparatus for an internal combustion engine disclosed in Patent Document 1, a manual regeneration switch for switching on and off by a user is provided in the instrument panel in order to continue the regeneration processing of the filter member.
As a result, the exhaust gas purification apparatus for an internal combustion engine automatically performs a regeneration process for the filter member when there is a request for stopping the internal combustion engine (ignition key off) when the manual regeneration switch is on.

However, in this configuration, since the manual regeneration switch can be turned on in advance by the user, if the user forgets to perform the on operation (forgets to perform the off operation), driving There is a problem that the regeneration process is performed even during a period when the person is not trying to perform the regeneration process of the filter member.
Therefore, an object of the present invention is to execute the regeneration process of the filter member only for an appropriate period.

  In order to solve the above problems, (1) according to one aspect of the present invention, an internal combustion engine is operated by being operated in an exhaust gas purification apparatus of an internal combustion engine that is disposed in an exhaust system of the internal combustion engine and regenerates a filter member that purifies exhaust gas. A stop instructing unit for instructing to stop the engine, a regeneration instructing unit for instructing regeneration of the filter member by being operated, and prohibiting the stop of the internal combustion engine when the stop instructing unit is operated A driving stop prohibiting unit; an operation state detecting unit that detects an operating state of the stop instructing unit and the regeneration instructing unit when the driving stop prohibiting unit prohibits the stop of the internal combustion engine; and A drive stop unit that stops driving of the internal combustion engine when an operation of the instruction unit is detected; and a drive stop unit that controls the internal combustion engine when the operation state detection unit detects an operation of the regeneration instruction unit. Can provide an exhaust gas purification system of an internal combustion engine, characterized in that it comprises, a reproduction processing unit that reproduces handle member.

(2) In one aspect of the present invention, the operation state detection unit includes the stop instruction unit and the stop instruction unit only during a period until a preset time elapses after the drive stop prohibition unit prohibits the stop of the internal combustion engine. An operation state of the reproduction instruction unit is detected.
(3) In an aspect of the present invention, the operation state detection unit cannot detect the operation of the stop instruction unit and the regeneration instruction unit, and stops driving the internal combustion engine when the preset time has elapsed.

According to the invention of the aspect of (1), after the occupant operates the stop instructing unit and prohibits the stop of the internal combustion engine, the drive of the internal combustion engine is stopped or the internal combustion engine is driven to regenerate the filter member. It can be selected by the selection operation of the stop instruction unit and the reproduction instruction unit.
Therefore, in the present invention, for example, in a situation where the remaining amount of fuel is insufficient, the occupant can select to stop the internal combustion engine and prevent fuel consumption.

Thus, according to the present invention, the occupant can select whether to stop the drive of the internal combustion engine or to regenerate the filter member by controlling the drive of the internal combustion engine by the selection operation of the stop instruction unit and the regeneration instruction unit. Therefore, the filter member regeneration process can be executed for an appropriate period.
According to the invention of the aspect of (2), the occupant can stop the driving of the internal combustion engine or filter because a sufficient time for examining the state of the vehicle is obtained by the standby period which is a preset time. It is possible to appropriately select whether to regenerate the member.

According to the invention of the aspect of (3), the internal combustion engine is not operated in accordance with the operation of the previous stop instruction unit after the standby period, which is a preset time, has been detected without detecting any operation of the stop instruction unit and the regeneration instruction unit. Can be stopped.
Thus, in the present invention, for example, even if the occupant forgets to operate the stop instruction unit and the regeneration instruction unit within the standby period and leaves the vehicle while driving the internal combustion engine, the standby period After the lapse of time, the driving of the internal combustion engine can be stopped. For this reason, the present invention is effective in preventing wasteful consumption of fuel and preventing theft.

It is a figure which shows the structural example of the intake / exhaust system of the vehicle which has DPF regenerated by the DPF regeneration apparatus of this embodiment. It is a block diagram which shows the structural example of a DPF reproduction | regeneration apparatus. It is a figure which shows the structural example of an instrument panel. It is a flowchart which shows the process example of DPF regeneration control by ECU. It is a flowchart which shows a part of process example of DPF regeneration control by ECU. It is a flowchart which shows a part of process example of DPF regeneration control by ECU.

Embodiments of the present invention will be described with reference to the drawings.
(Constitution)
First, FIG. 1 shows a configuration example of a vehicle intake / exhaust system in the present embodiment. As shown in FIG. 1, this vehicle has a DPF 7 that is regenerated by a DPF (Diesel particulate filter) regenerating apparatus to which the present invention is applied.

  As shown in FIG. 1, in an intake / exhaust system of a vehicle, an intake passage 1 is provided with an intake adjustment device 2 having an open / close valve in an upstream collecting pipe 1 a, and a fuel injection having a fuel injection valve directly above an engine 3. A device 4 is provided. The fuel injection device 4 injects fuel by controlling the fuel injection amount of the fuel injection valve, the fuel injection timing, and the like by an ECU (Electronic Control Unit) 20 described later. Further, the intake air adjusting device 2, the valve opening degree of the open / close valve and the like are controlled by the ECU 20 to adjust the intake air.

  Further, the collecting pipe 5a of the exhaust passage 5 is provided with a catalyst 6 and a DPF 7 toward the downstream side. The catalyst 6 removes carbon monoxide, hydrocarbons, and particulate matter that are easily oxidized. The DPF 7 collects particulate matter in the exhaust gas, and regenerates the collection function by forcibly burning the collected particulate matter when the exhaust gas temperature reaches a set temperature or higher. The DPF 7 is regenerated by the DPF regeneration device of this embodiment.

FIG. 2 is a block diagram illustrating a configuration example of the DPF regeneration device.
As shown in FIG. 2, the vehicle 10 equipped with the DPF regeneration device further includes a vehicle speed sensor 11, an accelerator sensor 12, exhaust pressure sensors 13, 14, a filter temperature sensor 15, a DPF regeneration switch 16, a starter switch 17, an ECU 20, And a warning device 50.

  The vehicle speed sensor 11 detects the vehicle speed. Then, the vehicle speed sensor 11 outputs a detection value to the ECU 20. The accelerator sensor 12 detects the amount of depression of the accelerator pedal or the opening of the throttle valve. Then, the accelerator sensor 12 outputs the detected value to the ECU 20. For example, the accelerator sensor 12 is an angle sensor. Further, as shown in FIG. 1, the exhaust pressure sensors 13 and 14 are respectively arranged in the immediate vicinity of the upstream side and the downstream side of the DPF 7 and detect the exhaust pressure. Each exhaust pressure sensor 13, 14 outputs a detected value to the ECU 20. The filter temperature sensor 15 detects the temperature of the DPF 7. Then, the filter temperature sensor 15 outputs the detected value to the ECU 20.

  The DPF regeneration switch 16 is operated by the occupant and outputs a DPF regeneration command signal Pt corresponding to the operation state to the ECU 20. The starter switch 17 is, for example, a push-type switch (push starter switch), and is operated by an occupant to output an engine drive instruction signal (engine stop instruction signal) Ps corresponding to the operation state to the ECU 20.

Further, the warning device 50 is controlled by the ECU 20 to output a warning. In the present embodiment, the warning device 50 includes a warning sound output unit 51 and a warning display unit 52, which are controlled by the ECU 20.
FIG. 3 is a diagram illustrating a configuration example of the instrument panel 60. FIG. 3 shows a configuration example in which the steering wheel is not described.

  As shown in FIG. 3, the instrument panel 60 is provided with a warning device 50. In the present embodiment, the warning device 50 is provided in the indicator 61 of the instrument panel 60. Further, the DPF regeneration switch 16 is provided on the left side of the instrument panel 60, and the starter switch 17 is provided on the right side of the instrument panel 60.

  Returning to FIG. 2, the ECU 20 is configured in a controller including a microcomputer and its peripheral circuits. For example, the ECU 20 includes a CPU, a ROM, a RAM, and the like. The ROM stores one or more programs for realizing various processes. The CPU executes various processes according to one or more programs stored in the ROM.

In the present embodiment, the ECU 20 includes an information acquisition unit 21, a process determination unit 22, an input determination unit 23, an accumulation amount estimation unit 24, a time count unit 25, a standby count unit 26, an engine stop control unit 27, and an engine stop prohibition control unit. 28, a warning output control unit 29, a first DPF regeneration control unit 30, a second DPF regeneration control unit 31, and a storage unit 40.
Here, FIGS. 4 to 6 show flowcharts of processing examples of DPF regeneration control by the ECU 20. The ECU 20 repeatedly executes FIGS. 4 to 6 every 10 msec, for example.
In the following, the processing procedures of FIGS. 4 to 6 will be described, and the processing contents of each part of the ECU 20 will be described.

  As shown in FIG. 4, first, in step S <b> 1, the information acquisition unit 21 acquires various information used in the subsequent processing. Specifically, the information acquisition unit 21 acquires detection values from the vehicle speed sensor 11, the accelerator sensor 12, the exhaust pressure sensors 13 and 14, and the filter temperature sensor 15. In addition, the information acquisition unit 21 acquires a timer count value T (timer timer count 41 shown in FIG. 2) and a standby count value Ct (standby count value 42 shown in FIG. 2) stored in the storage unit 40.

Here, the timer count value T is a time required to complete the regeneration process of the DPF 7 by the second DPF regeneration control. For example, the timer count value T is determined experimentally, empirically, or theoretically.
The standby count value Ct is determined experimentally, empirically, or theoretically. The standby count value Ct is, for example, 60 seconds.

  Next, in step S <b> 2, the accumulation amount estimation unit 24 estimates the accumulation amount of fine particles on the DPF 7. Specifically, the accumulation amount estimation unit 24 estimates the accumulation amount of fine particles based on the differential pressure between the exhaust pressure sensor 13 on the upstream side and the exhaust pressure sensor 14 on the downstream side of the DPF 7 acquired in step S1. . Here, the accumulation amount estimation unit 24 estimates that the larger the differential pressure, the larger the accumulation amount of fine particles. For example, the accumulation amount estimation unit 24 refers to a table prepared in advance stored in the storage unit 40 and estimates the accumulation amount corresponding to the differential pressure. Alternatively, the deposition amount per time may be set in advance, and the duration may be calculated to estimate the deposition amount.

Next, in step S3, the process determination unit 22 determines whether or not the accumulation amount estimation value A acquired in step S2 is equal to or greater than a preset value (set value) Ath1. Here, the set value Ath1 is a value set to start the regeneration process of the DPF 7, and is, for example, a fine particle accumulation amount that prevents the DPF 7 from properly functioning. This set value Ath1 is, for example, a value set experimentally, empirically, or theoretically. When the process determination unit 22 determines that the accumulation amount estimated value A is equal to or greater than the set value Ath1 (A ≧ Ath1), the process proceeds to step S4. Further, when the process determination unit 22 determines that the accumulation amount estimated value A is less than the set value Ath1 (A <Ath1), the process proceeds to step S7.
In step S4, the first DPF regeneration control unit 30 executes first DPF regeneration control. Further, the first DPF regeneration control unit 30 sets the first DPF regeneration control flag Ds to 1 (Ds = 1).

  Here, the first DPF regeneration control unit 30 performs, as the first DPF regeneration control, fuel injection amount correction control for increasing the fuel injection amount in the fuel injection device 4 or fuel injection timing delay control for delaying the fuel injection timing. Here, the first DPF regeneration control is different from the second DPF regeneration control performed by the second DPF regeneration control unit 31 described later, and the driving state of the engine 3 for regenerating the DPF 7 in accordance with the operating state of the engine 3 while the vehicle is traveling. To change. Specifically, the first DPF regeneration control unit 30 changes the fuel injection amount or the fuel injection timing as the driving state of the engine 3. For example, when the first DPF regeneration control unit 30 determines that the driver's accelerator depression amount is large and there is an acceleration request based on the detection value from the accelerator sensor 12 acquired in step S1, the increase amount of fuel injection Adjust the so that it is close to the appropriate injection amount. Further, the first DPF regeneration control unit 30 returns the fuel injection timing from the delayed state to approach an appropriate combustion state under the same conditions. That is, when there is an acceleration request, the first DPF regeneration control unit 30 drives and controls the engine 3 so that the priority of the acceleration request becomes higher and the priority of the regeneration process of the DPF 7 becomes lower.

  Next, in step S5, the process determination unit 22 determines whether or not the DPF temperature Td acquired by the filter temperature sensor 15 in step S1 is equal to or higher than a preset value (set value) Tdth. Here, the set value Tdth is the minimum temperature of the DPF 7 necessary for proceeding with the regeneration of the DPF 7, and is, for example, a value set experimentally, empirically, or theoretically. This set value Tdth is, for example, 300 ° C. If the process determination unit 22 determines that the DPF temperature Td is equal to or higher than the set value Tdth (Td ≧ Tdth), the process proceeds to step S6. If the process determining unit 22 determines that the DPF temperature Td is lower than the set value Tdth (Td <Tdth), the process proceeds to step S8.

In step S6, the time counting unit 25 starts counting down the time timer count value T acquired in step S1. Then, the time counting unit 25 proceeds to step S6.
In step S7, the time counting unit 25 resets the time counting count T. Then, the time counting unit 25 proceeds to step S8.

  Next, in step S8, the process determination unit 22 determines whether or not the vehicle has stopped. Specifically, the process determination unit 22 determines whether or not the vehicle speed V is less than a preset value (set value) Vth. If the vehicle speed V is less than the set value Vth, it is determined that the vehicle has stopped. To do. When the process determination unit 22 determines that the vehicle has stopped (V <Vth), the process proceeds to step S9. Moreover, if the process determination part 22 determines with the vehicle not stopping (V> = Vth), it will start a process again from the said step S1.

  In step S <b> 9, the input processing unit 23 determines whether or not the starter switch 17 is pressed based on an output signal (operation signal) from the starter switch 17. Thereby, the input processing unit 23 determines whether or not there has been an engine stop request. If the input processing unit 23 determines that the starter switch 17 has been pressed, the process proceeds to step S10. Here, the starter switch 17 outputs an engine stop command signal Ps = 1 when an operation for stopping the engine is performed by a passenger, and the input processing unit 23 detects the engine stop command signal Ps = 1. Proceed to step S10. If the input processing unit 23 determines that the starter switch 17 has not been pressed, the input processing unit 23 starts the process again from step S1.

  In step S10, the process determination unit 22 determines whether or not the first DPF regeneration control is being executed. Specifically, the process determination unit 22 determines whether or not the first DPF regeneration control flag Ds is set to 1, and when the first DPF regeneration control flag Ds is set to 1, the first DPF regeneration control is performed. Determine that it is running. If the process determination unit 22 determines that the first DPF regeneration control is being executed, the process proceeds to step S11. If the process determination unit 22 determines that the first DPF regeneration control is not being executed, the process proceeds to step S22.

  In step S11, as in step S5, the process determination unit 22 determines whether or not the DPF temperature Td acquired by the filter temperature sensor 15 in step S1 is equal to or higher than a preset value (set value) Tdth. . If the process determination unit 22 determines that the DPF temperature Td is equal to or higher than the set value Tdth (Td ≧ Tdth), the process proceeds to step S12. If the process determination unit 22 determines that the DPF temperature Td is lower than the set value Tdth (Td <Tdth), the process proceeds to step S22.

In step S12, the engine stop prohibition control unit 28 prohibits the engine stop process. Specifically, the engine stop prohibition control unit 28 cancels the engine stop command signal Ps from the starter switch 17 (Ps = 0).
Next, in step S13, the first DPF regeneration control unit 30 stops the first DPF regeneration control. Further, the first DPF regeneration control unit 30 sets the first DPF regeneration control flag Ds to 0 (Ds = 0).

  Next, in step S14, the second DPF regeneration control unit 31 performs second DPF regeneration control. Further, the second DPF regeneration control unit 31 sets the second DPF regeneration control flag Dt to 1 (Dt = 1).

  Here, as the second DPF regeneration control, the second DPF regeneration control unit 31 performs the fuel injection amount correction control for increasing the fuel injection amount in the fuel injection device 4 or the fuel injection timing delay control for delaying the fuel injection timing. Here, unlike the first DPF regeneration control, the second DPF regeneration control is a control while the vehicle is stopped, and the drive of the engine 3 is controlled according to preset drive control contents that do not depend on the operating state of the engine 3. That is, the second DPF regeneration control unit 31 controls the drive of the engine 3 with a predetermined fuel injection amount or fuel injection timing set in advance.

Next, in step S15, the warning output control unit 29 controls the warning sound output unit 51 to output a warning sound. For example, the warning output control unit 29 outputs a buzzer or a beep sound several times from the warning sound output unit 51.
Next, in step S16, the standby count unit 26 starts counting down the standby count value Ct acquired in step S1.

  Next, in step S <b> 17, the input determination unit 23 determines whether or not the DPF regeneration switch 16 has been pressed based on an output signal (operation signal) from the DPF regeneration switch 16. Specifically, the input determination unit 23 determines whether or not the DPF regeneration command signal Pt from the DPF regeneration switch 16 is 1, and when the DPF regeneration command signal Pt is 1, the DPF regeneration switch 16 is pressed. It is determined that If the input determination unit 23 determines that the DPF regeneration switch 16 has been pressed (Pt = 1), the process proceeds to step S31 in FIG. If the input determination unit 23 determines that the DPF regeneration switch 16 is not pressed (Pt = 0), the process proceeds to step S18.

  In step S <b> 18, the input determination unit 23 determines whether the starter switch 17 has been pressed based on the output signal from the starter switch 17. Specifically, the input determination unit 23 determines whether or not the engine stop command signal Ps 1 is output from the starter switch 17 again. When the input determination unit 23 determines that the starter switch 17 has been pressed (Ps = 1), the process proceeds to step S21. If the input determination unit 23 determines that the starter switch 17 has not been pressed (Ps = 0), the process proceeds to step S19.

In step S19, the input determination unit 23 determines whether or not a vehicle start request has been made. Specifically, the process determination unit 22 determines whether or not the vehicle speed V is equal to or higher than a preset value (set value) Vth based on the detection value from the vehicle speed sensor 11 acquired in step S1. When the vehicle speed V is equal to or higher than the set value Vth, it is determined that there is a vehicle start request. When the input determination unit 23 determines that there is a vehicle start request (V ≧ Vth), the process proceeds to step S51 in FIG. When the input determination unit 23 determines that there is no vehicle start request (V <Vth), the process proceeds to step S20.
In addition, the input determination part 23 can also determine with the start request | requirement of a vehicle having been received, when depression operation of the accelerator pedal by a driver | operator is detected.

  In step S20, the input determination unit 23 determines whether or not the countdown of the standby count value Ct has ended. Specifically, when the standby count value Ct is 0, the input determination unit 23 determines that the countdown of the standby count value Ct has ended. If the input determination unit 23 determines that the countdown of the standby count value Ct has ended, the process proceeds to step S21. If the input determination unit 23 determines that the countdown of the standby count value has not ended, the input determination unit 23 starts the process again from step S17.

In step S21, the warning output control unit 29 ends the warning. That is, the warning output control unit 29 ends the output if the warning sound is output in step S15 and the output is continued. Then, the warning output control unit 29 proceeds to step S22.
In step S22, the engine stop control unit 27 executes engine stop control to stop the engine 3. Then, the ECU 20 ends the process shown in FIG.

In FIG. 5, first, in step S31, the warning output control unit 29 controls the warning display unit 52 to turn on the warning lamp.
Next, in step S32, the accumulation amount estimation unit 24 estimates the accumulation amount of fine particles on the DPF 7 by the same process as in step S2.

  Next, in step S33, the input determination unit 23 determines whether or not there is a vehicle start request. Specifically, the process determination unit 22 determines whether or not the vehicle speed V is equal to or higher than a preset value (set value) Vth. If the vehicle speed V is equal to or higher than the set value Vth, there is a vehicle start request. It is determined that When the input determination unit 23 determines that there is a vehicle start request (V ≧ Vth), the process proceeds to step S51 in FIG. If the input determination unit 23 determines that there is no vehicle start request (V <Vth), the process proceeds to step S34.

  In step S34, the process determination unit 22 determines whether or not the regeneration of the DPF 7 has been completed. Specifically, the process determining unit 22 determines whether or not the time count value T is 0, or whether or not the estimated deposition value A acquired in step S32 is less than the set value Ath2. Here, when the timekeeping timer count value T is 0 (T = 0), or when the estimated accumulation value A is less than the set value Ath2 (A <Ath2), the process determination unit 22 completes the regeneration of the DPF 7 It is determined that Ath2 may be set to the same value as Ath1 in step S3, but may preferably be set to a value lower than Ath1. If the process determination unit 22 determines that the regeneration of the DPF 7 is completed, the process determination unit 22 proceeds to step S21 in FIG. If the process determining unit 22 determines that the regeneration of the DPF 7 has not been completed, the process determining unit 22 performs the process again from step S33.

At this time, in step S21, the warning output control unit 29 turns off the warning lamp and stops outputting the warning sound to end the warning.
In FIG. 6, first, in step S51, the second DPF regeneration control unit 31 stops the second DPF regeneration control. Further, the second DPF regeneration control unit 31 sets the second DPF regeneration control flag Dt to 0 (Dt = 0).

  Next, in step S52, the process determination unit 22 determines whether or not the clock timer count value T is zero. If the process determination unit 22 determines that the timer count value T is 0 (T = 0), the process proceeds to step S54. If the process determination unit 22 determines that the timer count value T is not 0, the process proceeds to step S53.

In step S53, the first DPF regeneration control unit 30 executes first DPF regeneration control. Further, the first DPF regeneration control unit 30 sets the first DPF regeneration control flag Ds to 1 (Ds = 1). Then, the first DPF regeneration control unit 30 proceeds to step S54.
In step S54, the warning output control unit 29 turns off the warning lamp and stops the output of the warning sound to end the warning.

(Operation, action, etc.)
Next, the operation and action of the DPF regeneration device will be described.
The DPF regeneration device first acquires information from the vehicle speed sensor 11 and the like (step S1). Further, the DPF regeneration device estimates the particulate accumulation amount of the DPF 7, and executes the first DPF regeneration control and sets the first DPF regeneration control flag Ds to 1 when the accumulation amount estimated value A is equal to or greater than the set value Ath1 while the vehicle is traveling. If the DPF temperature Td is equal to or higher than the set value Tdth, the timer count value T is counted down (step S1 to step S6, step S8). Further, even when the vehicle stops, the DPF regeneration device similarly performs the first DPF regeneration control and sets the first DPF regeneration control flag Ds to 1 until the starter switch 17 is operated to stop the engine. The timer count value T is counted down (step S1 to step S6, step S8, step S9). Further, when the DPF temperature Td is lower than the set value Tdth, the DPF regeneration device stops counting down the time-counting timer count value T during that period (steps S5 and S6).

  When the starter switch 17 is operated to stop the engine after the vehicle stops, the DPF regeneration device is based on the operation of the starter switch 17 if the first DPF regeneration control is being executed and the DPF temperature Td is equal to or higher than the set value Tdth. The engine stop process is prohibited and the idling state is maintained. Further, the DPF regeneration device switches the DPF regeneration control from the first DPF regeneration control to the second DPF regeneration control, sets the second DPF regeneration control flag Dt to 1, and outputs a warning sound (steps S8 to S15). Further, the DPF regeneration device does not execute the first DPF regeneration control when the starter switch 17 is operated to stop the engine after the vehicle stops (for example, regeneration of the DPF 7 has already been completed by the first DPF regeneration control), If the first DPF regeneration control is executed but the DPF temperature Td is lower than the set value Tdth, an engine stop process based on the engine stop operation of the starter switch 17 is executed (steps S8 to S11, step S22).

As described above, the DPF regeneration device switches the DPF regeneration control while the vehicle is stopped to the second DPF regeneration control, so that the DPF 7 is regenerated by the DPF regeneration control having the regeneration capability that matches the operation state of the engine 3 while the vehicle is stopped. it can.
Further, the DPF regeneration device thus switches the DPF regeneration control from the first DPF regeneration control to the second DPF regeneration control, and then starts to count down the standby count value Ct, and the countdown of the standby count value Ct ends (Ct = 0). It is determined whether or not a predetermined condition is satisfied during a period until the time is reached, that is, during a standby period corresponding to the standby count value Ct (steps S16 to S20). Specifically, the DPF regeneration device monitors the operation of the DPF regeneration switch 16, the operation of the starter switch 17, or the presence of a vehicle start request during the standby period.

If there is no operation of either the DPF regeneration switch 16 or the starter switch 17 and there is no vehicle start request during the standby period, the DPF regeneration device terminates the output of the warning sound and executes the engine stop process (step S16). -Step S22).
Further, even when the starter switch 17 is operated during the standby period (the starter switch 17 is pressed twice), the DPF regeneration device terminates the output of the warning sound and executes the engine stop process (step S18). Step S21, Step S22).

  On the other hand, when the DPF regeneration switch 16 is operated during the standby period, the DPF regeneration device turns on the warning lamp (step S31). Thereafter, the DPF regeneration device estimates the amount of particulates deposited on the DPF 7 (step S32). In other words, the DPF regeneration device estimates the amount of particulate deposition at the time when the first DPF regeneration control is switched to the second DPF regeneration control. Then, when the regeneration of the DPF 7 is completed without a vehicle start request, the DPF regeneration device ends the output of the warning sound and turns off the warning light, and executes the engine stop process (steps S33, S34, and S21). Step S22).

Here, the DPF regeneration device estimates the accumulated amount estimated when the time count timer value T, which has started counting down from the start of execution of the first DPF regeneration control, becomes 0, or when switching to the second DPF regeneration control. When A is less than the set value Ath2, it is determined that the regeneration of the DPF 7 has been completed.
In addition, here, the regeneration completion determination is performed using the accumulation amount estimation value A estimated at the time of switching to the second DPF regeneration control, for the following reason.

  As described above, during the execution of the first DPF regeneration control, the fuel injection amount and the like constantly change according to the operating state of the engine 3 (for example, giving priority to the driver's acceleration operation), and the exhaust pressure also changes accordingly. . Therefore, if the fine particle accumulation amount is estimated using the exhaust pressure value during the execution of the first DPF regeneration control, an error may occur in the accumulation amount estimation value. On the other hand, during the execution of the second DPF regeneration control, the second DPF regeneration control results in the fuel injection amount set in advance not depending on the operation state of the engine 3 and the exhaust pressure being in a stable state. Yes. Therefore, by estimating the particulate accumulation amount based on such an exhaust pressure value at the time of switching to the second DPF regeneration control, the particulate accumulation amount can be estimated with high accuracy, and completion of regeneration of the DPF 7 can be determined with high accuracy. is there. As a result, the DPF regeneration device can prevent useless regeneration processing time from occurring.

  In addition, the DPF regeneration device receives a vehicle start request before determining that regeneration of the DPF 7 is completed as described above (step S33), or during the standby period during execution of the second DPF regeneration control. When there is a start request (step S19), the second DPF regeneration control is stopped, the second DPF regeneration control flag Dt is set to 0, and after the warning is finished, the first step of the DPF regeneration control (step S1) is started. The process starts again (FIG. 6). At this time, if the clock timer count value T is not 0, the DPF regeneration device starts the process again from the first step (step S1) after starting the first DPF regeneration control (step S52 to step S54). ). Further, the DPF regeneration device restarts the process from the first step (step S1) without starting any regeneration control of the first and second DPF regeneration controls when the time count value T is 0. (Step S52, Step S54).

  With the DPF regeneration device that operates as described above, for example, the occupant stops the vehicle during the execution of the first DPF regeneration control and performs the engine stop operation of the starter switch 17 and then within a preset standby period. The engine 3 is stopped by operating the starter switch 17 again, or the regeneration process of the DPF 7 (the regeneration process by the second first DPF regeneration control) is continued until the regeneration is completed by operating the DPF regeneration switch 16. can do.

  Further, the DPF regeneration device automatically returns to the first DPF regeneration control when there is a vehicle start request during the standby period, or when there is no switch operation or vehicle start request during the standby period. Later, the engine 3 can be automatically stopped to end the DPF regeneration control (second DPF regeneration control).

  In the description of the above-described embodiment, the DPF 7 constitutes a filter member, for example. The starter switch 17 constitutes a stop instruction unit, for example. The DPF regeneration switch 16 constitutes a regeneration instruction unit, for example. The engine stop prohibition control unit 28 constitutes a drive stop prohibition unit, for example. Moreover, the input determination part 23 comprises the operation state detection part, for example. Moreover, the engine stop control part 27 comprises a drive stop part, for example. Moreover, the 1st DPF regeneration control part 30 and the 2nd DPF regeneration control part 31 comprise a regeneration control part, for example.

(Modification of this embodiment)
In this embodiment, the DPF regeneration control is divided into the first DPF regeneration control and the second DPF regeneration control. However, the present invention is not limited to this. That is, for example, the control content of the DPF regeneration control can be set to be equivalent to the control content of either the first DPF regeneration control or the second DPF regeneration control. In this case, for example, if the control content of the DPF regeneration control is only equivalent to the control content of the first DPF regeneration control, the DPF regeneration device has the engine stop operation of the starter switch 17 during the execution of the first DPF regeneration control while the vehicle is stopped. Also, the execution of the first DPF regeneration control is maintained.

  In the present embodiment, the DPF regeneration device can also set the timer count value T based on the accumulated amount estimated value acquired by the accumulated amount estimating unit 24. In this case, the time-counting timer count value T increases as the accumulation amount estimation value increases. For example, the DPF regeneration device refers to a previously prepared table or the like stored in the storage unit 40, and sets a timer count value T corresponding to the accumulated amount estimated value. Therefore, as described above, when the time count value T is set to correspond to the time required for completing the regeneration process of the DPF 7 by the second DPF regeneration control, the time count value T corresponds to the estimated accumulation amount. This is equivalent to the time required to regenerate the DPF 7 estimated to be accumulated by the second DPF regeneration control.

  Further, in this embodiment, in such a configuration, the particle accumulation amount is estimated after the starter switch 17 is operated, and the time count timer count value T is set based on the estimated particle accumulation amount. Conceivable. However, in this case, a waiting time for the processing occurs from when the starter switch 17 is pressed until the timing timer count value T is set, and as a result, the regeneration processing of the DPF 7 is prolonged and the fuel is consumed. There is a risk of being wasted. On the other hand, in the present embodiment, the amount of accumulated particulates is estimated before the starter switch 17 is pressed, and the timer count value T is set based on the estimated amount of accumulated particulates. Since the setting can be made without the waiting time, it is possible to prevent the regeneration process of the DPF 7 from being prolonged and the fuel from being wasted.

  In this embodiment, the amount of particulate deposition is estimated in step S32 when switching to the second DPF regeneration control, and the regeneration of the DPF 7 is determined to be complete in step S34 based on the estimated amount of deposition estimated. It is not limited to. For example, in the present embodiment, it is possible to determine completion of regeneration of the DPF 7 in step S34 based on the estimated accumulation amount acquired in step S2. In such a configuration, in this embodiment, after step S2, it is not necessary to operate the exhaust pressure sensor 14 used for estimating the accumulation amount, so that power supply to the exhaust pressure sensor 14 is performed. It can also be turned off.

In the present embodiment, the configurations of the DPF regeneration switch 16 and the starter switch 17 are specifically described, but it is needless to say that the present invention is not limited to this.
In the embodiment, the time-counting timer count value T is counted down in the step S5, and it is determined whether or not the time-counting timer count value T has become 0 in the step S34 or the step S52 as a process corresponding thereto. . However, the present embodiment is not limited to such a configuration example. For example, in the present embodiment, the count-up is performed in step S5, and as a process corresponding thereto, the value counted up in step S34 or step S52 reaches a preset value (for example, a timer count value T). It can also be determined whether or not.

  In the embodiment, the countdown of the standby count value Ct is started in step S16 (countdown according to the actual time), and as a process corresponding thereto, whether or not the standby count value Ct has become 0 in step S20 is determined. Judgment. However, the present embodiment is not limited to such a configuration example. For example, in the present embodiment, counting up (counting up according to real time) is started in step S16, and the value (elapsed time) counted up in step S1 is a preset value as processing corresponding thereto. It can also be determined whether or not (for example, the standby count value Ct) has been reached.

  Further, although the embodiments of the present invention have been specifically described, the scope of the present invention is not limited to the illustrated and described exemplary embodiments, and effects equivalent to those intended by the present invention. All embodiments that provide are also included. Further, the scope of the present invention is not limited to the combination of features of the invention defined by claim 1 but can be defined by any desired combination of specific features among all the disclosed features. .

  3 Engine, 7 DPF, 15 Filter temperature sensor, 16 DPF regeneration switch, 17 Starter switch, 20 ECU, 22 Process determination unit, 23 Input determination unit, 24 Accumulation amount estimation unit, 30 1st DPF regeneration control unit, 31 2nd DPF regeneration Control unit, 25 Time counting unit, 27 Engine stop control unit, 28 Engine stop prohibition control unit

Claims (3)

In an exhaust gas purification apparatus for an internal combustion engine that is disposed in an exhaust system for an internal combustion engine and regenerates a filter member that purifies exhaust gas,
A stop instruction unit for instructing to stop the internal combustion engine by being operated;
A regeneration instruction unit for instructing regeneration of the filter member by being operated;
A drive stop prohibiting portion for prohibiting the stop of the internal combustion engine when the stop instructing portion is operated;
An operation state detection unit for detecting operation states of the stop instruction unit and the regeneration instruction unit when the drive stop prohibition unit prohibits the stop of the internal combustion engine;
A drive stop unit that stops driving of the internal combustion engine when the operation state detection unit detects an operation of the stop instruction unit;
A regeneration processing unit that drives and controls the internal combustion engine to regenerate the filter member when the operation state detection unit detects an operation of the regeneration instruction unit;
An exhaust emission control device for an internal combustion engine, comprising:   The operation state detection unit detects the operation states of the stop instruction unit and the regeneration instruction unit only during a period until a preset time elapses after the drive stop prohibition unit prohibits the stop of the internal combustion engine. The exhaust emission control device for an internal combustion engine according to claim 1. 3. The driving of the internal combustion engine is stopped when the preset time has elapsed without the operation state detection unit being able to detect operations of the stop instruction unit and the regeneration instruction unit. An exhaust purification device for an internal combustion engine.

Images