JPH06101450A - Exhaust gas purifying device for diesel engine - Google Patents

Abstract

PURPOSE:To provide an exhaust gas purifying device which is caused to prevent the stop of operation of an engine in the middle of running even when a vehicle is started again by a driver to key OFF during continuance of regeneration, in an exhaust gas purifying device to continue regeneration through continuance of operation even when key OFF is effected during the regeneration of a filter. CONSTITUTION:In an exhaust gas purifying device having a filter 2 and an electric heater 3, a lapse time Toff between OFF of an engine key switch 7 and the restarting of a vehicle is measured. It is decided from the length of the lapse time whether a present driver is the same as a driver to effect OFF of an engine key. When the present driver is the same, operation is continued even after the regeneration of the filter and when the present drive is not the same, the feed of fuel to an engine E is stopped to bring running of a vehicle into an impossible state.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust gas purification apparatus having a filter for trapping particulate matter contained in exhaust gas of a diesel engine in an exhaust passage, and particularly when the engine key is turned off during filter regeneration. ,
The present invention relates to an exhaust emission control device that continues engine operation until filter regeneration is completed (strictly speaking, heater energization is completed).

[0002]

2. Description of the Related Art Generally, exhaust gas of a diesel engine contains a large amount of exhaust particulates, that is, particulates. Therefore, a filter for collecting particulates is attached to the exhaust passage of the engine. As the amount of particulates accumulated inside the filter increases as it is used, the air permeability gradually deteriorates and engine performance deteriorates.Therefore, it is regularly regenerated depending on the amount of particulates collected. It is supposed to be done. The filter regeneration means, for example, activating the regeneration means such as an electric heater provided on the end face of the filter or an electric air pump for supplying the air required for particulate combustion, so that the particulates are ignited and combusted, and the air permeability of the filter is regained. Means to secure.

In the exhaust gas purifying apparatus as described above, if the engine operation is stopped (engine key-off) while the filter is being regenerated, the electric heater and the air pump are usually stopped due to the key-off. , The filter is in an incomplete playback state,
At the time of restart, if the particulate collection is restarted in this state, problems such as a reduction in collection efficiency and a reduction in the accuracy of regeneration timing determination will occur.

Therefore, in order to solve such a problem, the actual Kaihei 3-4
According to Japanese Patent No. 3519, even if the engine key is turned off during the filter regeneration, the engine operation is continued and the heater and the air pump are supplied with electricity for the filter regeneration until the filter regeneration is completed. An exhaust emission control device is disclosed in which the engine operation is stopped after completion.

[0005]

However, in the exhaust gas purifying apparatus of the type described above, the driver who temporarily shuts off the engine key under the condition that the engine continues to run to continue the filter regeneration despite the engine key off. However, if the engine operation is confirmed and the vehicle is started again with the engine key off, the engine will stop after the filter regeneration is completed, and the driver must start the engine again. It was inconvenient.

In view of the problem of such a regeneration continuing type exhaust gas purifying apparatus, the present invention can avoid an unintended engine stoppage in the middle of traveling even if the driver who has the engine key off starts the vehicle in the regeneration continuing state. The purpose of the present invention is to provide an exhaust gas purification device.

[0007]

To achieve the above object, according to the present invention, there is provided a filter provided in an exhaust passage of a diesel engine for collecting particulates in exhaust gas, and a particulate collection amount of the filter. A diesel engine exhaust purification device that continues the engine operation during filter regeneration even when the engine key is off during filter regeneration, and filter regeneration after engine key off. When the vehicle is started during, the vehicle driver at that time determines whether or not the engine key is off first, and if the engine key is off, the driver continues driving even after the engine is regenerated. If you are not the driver with the engine key off, Exhaust purification device for a diesel engine is provided, characterized in that it comprises a gin operation control means.

[0008]

When the engine key-off is performed during the filter regeneration, the engine operation is automatically continued and the vehicle continues to run after the regeneration vehicle is started and after the regeneration is finished. In order to prevent theft, stop the engine operation at the end of playback.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. With reference to FIG. 1 showing a schematic configuration of an exhaust emission control device of the present invention, 1 is an exhaust pipe (exhaust passage) through which exhaust gas from a diesel engine E flows, and 2 is a patty in exhaust gas provided in the exhaust pipe 1. A filter that collects curates,
An electric heater 3 is provided in the filter 2 and constitutes a regeneration means thereof. In addition to this, as the filter regenerating means, there is an air pump or the like for supplying a regenerating gas (for example, secondary air) for particulate combustion, but it is omitted here.

The electric heater 3 is electrically connected to the battery 4 so that power is supplied from the battery 4 at the time of filter regeneration, and energization is controlled by a heater relay 6 operated by a control circuit (ECU) 5. It has become so. Between the ECU 5 and the battery 4, an engine key switch (or an ignition switch) 7 that is operated by a driver when the engine is operated or stopped is provided. The engine key switch 7 will be described later. In order to supply electric power to the electric circuit of the vehicle even when the engine key is off according to the program
Sub ignition relay 8 whose operation is controlled by 5
Are electrically connected in parallel.

In the present embodiment, a shift position sensor 10 is provided in the transmission mechanism (T / M) 9 in order to determine whether the vehicle is in a driving state, that is, a traveling stop state or a traveling (starting) state. The shift position signals from here are always input to the ECU 5.
A fuel supply line connected from a fuel supply pump (not shown) to the engine E is provided with a normally open type fuel cut solenoid valve 11 that constitutes the operation control means of the present invention together with the ECU 5 and is controlled to open / close by the ECU 5. When the fuel supply is stopped, the ECU 5 turns on the fuel solenoid relay 12 provided between the fuel cut solenoid valve 11 and the battery 4, thereby closing the fuel supply path to the engine E. In this embodiment, E
Fuel solenoid relay 1 whose operation is controlled by CU5
An emergency stop switch 13 that allows the driver to manually stop the engine is connected in parallel to the switch 2.

[0012] Hereinafter, depending on the length of time elapsed from the time the engine key is turned off during the filter regeneration until the vehicle restarts,
The present invention will be described by taking as an example a device for determining whether or not the vehicle driver at the time of restarting is a driver who has turned off the engine key. A timer unit for measuring the elapsed time is provided in the ECU 5 described above. FIG. 2 is a flowchart showing a control routine of the ECU 5 of the exhaust purification system according to the present embodiment, and this routine is executed by the ECU 5 regardless of whether the engine is running or stopped.
In addition to this program, a conventional filter regeneration continuation processing program for operating the heater relay 6 according to the amount of particulate collection and energizing the electric heater 3 of the filter 2 is installed in the ECU 5, As long as electric power is supplied to the reproducing means, the reproducing process is executed as in the conventional case.

Referring to the routine of FIG. 2, it is determined in step 21 whether or not the engine key switch 7 is currently keyed off by the driver. If the key is not off (No), the engine E is driven. Since this is the state, the following steps are skipped and this routine is ended, and the routine proceeds to the next routine. If it is determined Yes in step 21 and the engine E is in the key-off state, the routine next proceeds to step 22 and activates the timer in the ECU 5 described above. The elapsed time Toff of is counted.

In step 23 following step 22, E
Whether or not the electric heater 3 is currently energized is determined by checking whether or not there is an output from the CU 5 to the heater relay 6, and here, No, that is, when filter regeneration is not in progress (or filter regeneration completion). In this case), the routine proceeds to step 27, and for example, the engine operation may be continued even though the engine key is off to continue the filter regeneration. Therefore, the fuel solenoid relay 12 is turned on in this case. The cut solenoid valve 11 is closed to stop the fuel supply to the engine E and stop the engine.

On the other hand, if it is determined Yes in step 23, and if the output is currently being made to the heater relay 6 and the heater is being energized despite the engine key being off, it is necessary to continue the filter regeneration. Therefore, in this case, the routine proceeds to step 24, where the sub-ignition relay 8 is turned on to continuously operate the electric circuit required for the operating state of the vehicle, and the fuel solenoid relay 12 is turned off to open the fuel cut solenoid valve 11. , So that fuel supply to the engine E is continued.

In step 25 following step 24, in the state where the filter regeneration is continued with the vehicle stopped as described above, it is determined whether the vehicle continues to be stopped or the driver is about to start the vehicle. judge. That is, here, the shift position sensor 1 described above is used.
By looking at the shift position of T / M by 0, it is determined whether the current shift position is P (parking) or N (neutral).

If it is determined Yes in this step 25 and the vehicle is currently stopped, then in step 26, is it determined whether the heater energization time has passed and the output from the ECU 5 to the heater relay 6 is currently stopped. Determine whether or not. If it is determined Yes in step 26,
Since the rest is only the particulate combustion propagation process that does not require much driving power, the process proceeds to step 27 so as to stop the engine operation, resets the elapsed time Toff from key-off together with the above-described fuel supply stop process, and executes this routine. finish. In this step 27, the sub-ignition relay 8 is not turned off for the remaining filter regeneration processing (for example, driving the secondary air supply air pump for particulate combustion), and the predetermined air pump drive time ends. It is preferable that it is turned off for the first time at the time.

On the other hand, if No in step 26, that is, if the heater is being energized, it is necessary to continue engine operation, so the routine skips step 27 and ends this routine. Here, returning to step 25 again, the case where it is determined to be No will be described. This state is T /
The shift position of M is any one of D, 1st, 2nd, and R. Specifically, the engine operation is continued because the filter is being regenerated even though the driver has turned off the engine key. In, the driver is trying to start the vehicle as it is or corresponds to a state in which the vehicle is traveling.

Therefore, in this embodiment, in such a state, when the current driver is the same as the driver who previously turned off the engine key, the engine operation is continued even when the heater energization is completed, and the vehicle is running. If there is a high possibility that the engine will not be stopped unintentionally and that the driver is not the same as the driver who turned off the engine key, the engine operation will be stopped at the same time when the heater energization is terminated to prevent vehicle theft as in the conventional case.

In order to achieve such a device operation, in the present embodiment, in step 28 following step 25, the elapsed time Toff from the engine key-off started in step 22 is checked, and the same driver of different sizes is used. Determine whether there is. In other words, this means that if the same driver is used, under the condition where the engine operation is continued with the engine key off, even if the vehicle is left for a period of time for a certain reason, etc. The situation in which a different driver (in extreme cases, a car thief) is driving is that the driver who is keying off leaves the vehicle, rather than after a short time. This is because it is possible that some time has passed.

Therefore, the elapsed time Toff from the key-off is longer than the predetermined time a (for example, 1 minute), and the step 2
When it is determined to be Yes in step 8, it is determined that the driver is not the same driver, and the routine proceeds to step 26 and subsequent steps to execute a process of stopping the engine operation when the heater energization is completed. For this, the elapsed time Tof from the key-off until the vehicle starts to travel
If f is shorter than the predetermined time a and it is determined No in step 28, it is determined that the driver who has turned off the engine key and the driver who actuated the shift lever this time are the same, and the routine proceeds to step 29 where the elapsed time is elapsed. Reset Toff,
The process proceeds to step 30.

Step 30 is provided on the assumption that the driver will stop the engine operation as necessary when the engine continues to be operated with the engine key off after the filter regeneration as described above. Then, for example, if the engine key switch 7 is turned on from the off position for a moment, the engine operation is immediately stopped.

That is, here, by looking at the position of the engine key switch, it is judged whether or not it is currently in the on position (may be a momentary on), and unless it is in the on state (N
o), the routine returns to step 25 and the shift position is P
Unless it is N or N, the steps 25, 28, 29 and 30 are circulated to continue the engine operation. On the other hand, the driver switches the engine key switch 7 from the previously off state to the on state in order to stop the engine operation.
If it is determined to be es, the routine returns to step 26, and it is confirmed whether or not the heater energization has ended. If the heater energization has ended, in step 27, fuel supply stop processing for engine operation stop is performed. As described above, as another means for stopping the engine operation when the present apparatus continues the operation despite the engine key-off, the present apparatus allows the driver to set the shift position to P or N. It is conceivable that the fuel cut solenoid valve 11 is operated by switching to the position (because it is determined as Yes in step 25) or the driver manually turns on the emergency stop switch 13 described above.

As described above, depending on the length of time elapsed from the engine key-off to the start of re-driving (when the shift position is other than P and N), the driver at the start of re-driving is the driver who is key-off during filter regeneration. Although the operation of the device of the present invention has been described based on the embodiment for determining whether or not there is any, the driver determination means of the present invention is not limited to the above embodiment, and for example, at the start of re-traveling and key-off. Change of the driving position at the time of detection, or at the start of re-driving, whether to continue / stop the engine operation at the end of filter regeneration under the condition of an active predetermined signal input from the owner driver side good.

[0025]

As described above, according to the present invention,
If the driver turns off the engine key during filter regeneration, the engine will continue to operate automatically after the regeneration of the vehicle is started even after the regeneration of the filter is started, which is unintended as seen in conventional exhaust emission control systems. A vehicle traveling stop is avoided.

On the contrary, in the case of a driver other than the engine key-off, the engine key-off is activated and the engine operation is stopped at the same time when the filter regeneration is completed as before, so that the vehicle is prevented from being stolen. be able to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an exhaust emission control device according to an embodiment of the present invention.

FIG. 2 is a flow chart of a control circuit for explaining an example of operation of the apparatus of the present invention.

[Explanation of symbols]

 1 ... Exhaust pipe 2 ... Filter 3 ... Electric heater 4 ... Battery 5 ... ECU 7 ... Engine key switch 11 ... Fuel cut solenoid valve 12 ... Fuel solenoid relay E ... Diesel engine

Claims (1)

[Claims] 1. A filter provided in an exhaust passage of a diesel engine for collecting particulates in exhaust gas, and a filter regeneration means for burning the particulates according to the amount of particulates collected by the filter, further comprising: A diesel engine exhaust purification system that continues engine operation during filter regeneration even when the engine key is turned off during filter regeneration, and a vehicle driver who starts the vehicle during filter regeneration after engine keyoff If the driver is the engine key-off, the engine continues to operate even after the engine is regenerated, and if the driver is not the engine key-off A diesel engine characterized by having means Gas purification equipment.