JP2023017565A - Control device for vehicle - Google Patents

Abstract

To provide a control device for a vehicle capable of suppressing deterioration of a charge state of a battery and wear of a starter at restart from idling stop of an internal combustion engine.SOLUTION: Restartability of an internal combustion engine when first fuel is used is inferior to that of the internal combustion engine when second fuel is used. When restart is performed by using the first fuel after satisfaction of a restart condition (Yes in Step S3), a control section determines whether or not a predetermined restart interruption condition is satisfied during the restart (Step S8). When the restart interruption condition is satisfied (Yes in Step S8), the control section interrupts the restart (Step S9), switches to the second fuel (Step S10), and resumes the restart (Step S11).SELECTED DRAWING: Figure 2

Description

The present invention relates to a vehicle control device.

2. Description of the Related Art In recent years, among vehicles such as automobiles, there are bi-fuel vehicles equipped with an engine that switches between two different types of fuel. As a conventional vehicle of this type, one described in Patent Document 1 is known. In Patent Document 1, in a bi-fuel internal combustion engine that can be operated on either CNG (Compressed Natural Gas), which is a gaseous fuel, or gasoline, which is a liquid fuel, fuel injection is performed at the time of fuel switching. A technique for correcting the amount, etc. is described. According to the technique described in Patent Document 1, it is possible to suppress torque steps and fluctuations at the time of fuel switching.

Japanese Patent Application Laid-Open No. 2004-211610

However, in the technique described in Patent Document 1, CNG has a higher ignition point than gasoline and does not have good startability of the engine. It could crank for an extended period of time, potentially draining the battery's state of charge or depleting the starter. These problems are more pronounced in vehicles with an idle stop function, since the engine automatically stops and restarts frequently.

The present invention has been made by focusing on the above problems, and is a vehicle control device capable of suppressing the deterioration of the state of charge of the battery and the consumption of the starting device when the internal combustion engine is restarted from an idle stop. It is intended to provide

The present invention is a control device for a vehicle equipped with an internal combustion engine that switches between a first fuel and a second fuel of different types, and automatically stops the internal combustion engine when a predetermined automatic stop condition is satisfied. and a control unit for restarting the internal combustion engine when a predetermined restart condition is satisfied while the internal combustion engine is automatically stopped, and the restartability of the internal combustion engine when the first fuel is used is determined by the above-described It is inferior to the restartability of the internal combustion engine when the second fuel is used. If the restart interruption condition is satisfied, the restart is interrupted, the second fuel is selected, and the restart is resumed.

As described above, according to the present invention, it is possible to provide a control device for a vehicle that can suppress the deterioration of the state of charge of the battery and the wear and tear of the starting device when the internal combustion engine is restarted from idle stop.

FIG. 1 is a configuration diagram of a vehicle equipped with a control device according to a first embodiment or a second embodiment of the invention. FIG. 2 is a flow chart for explaining the operation of the vehicle control device according to the first embodiment of the present invention. FIG. 3 is a flow chart for explaining the operation of the vehicle control device according to the second embodiment of the present invention.

A control device for a vehicle according to an embodiment of the present invention is a control device for a vehicle equipped with an internal combustion engine that switches between a first fuel and a second fuel that are different in type from each other, the control device having a predetermined automatic stop condition. is satisfied, the internal combustion engine is automatically stopped, and the internal combustion engine is restarted when a predetermined restart condition is satisfied during the automatic stop of the internal combustion engine, and the internal combustion engine is restarted when the first fuel is used. The restartability is inferior to the restartability of the internal combustion engine when the second fuel is used. It is characterized in that whether or not a restart interruption condition is satisfied is determined, and if the restart interruption condition is satisfied, the restart is interrupted, switched to the second fuel, and the restart is restarted. As a result, the vehicle control apparatus according to the embodiment of the present invention can suppress the deterioration of the state of charge of the battery and the consumption of the starting device when the internal combustion engine is restarted from idle stop.

A vehicle control apparatus according to a first embodiment of the present invention will be described below with reference to the drawings. 1 and 2 are diagrams for explaining a vehicle control apparatus according to a first embodiment of the present invention. As shown in FIG. 1, a vehicle 1 equipped with a vehicle control apparatus according to an embodiment of the present invention includes an internal combustion engine 2 (referred to as an engine in the drawing) as a drive source, and power from the internal combustion engine 2. A transmission 4 to which power is transmitted, a clutch 3 provided between the internal combustion engine 2 and the transmission 4, and driving wheels 5 to which power is transmitted from the transmission 4 are provided.

The vehicle 1 also includes an accelerator pedal sensor 12A, a brake pedal sensor 13A, a clutch pedal sensor 14A, a vehicle speed sensor 15, an acceleration sensor 16, and an ECU (Electronic Control Unit) that controls the internal combustion engine 2 and the transmission 4. 11.

The internal combustion engine 2 performs a series of four strokes consisting of an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke. It is configured. In addition to the internal combustion engine 2, the vehicle 1 may include a motor as a drive source. The vehicle 1 has a starter 6 as a starting device for starting the internal combustion engine 2 .

The starter 6 is driven by electric power supplied from a battery (not shown), and rotates (cranks) the output shaft 2A of the internal combustion engine 2 to start the internal combustion engine 2 . Note that the starting device is not limited to the starter 6 . If the vehicle 1 is a hybrid vehicle provided with a motor for running, the motor may be used as the starting device.

The transmission 4 is configured, for example, as a parallel shaft gear type transmission mechanism that is commonly used in manual transmissions. The clutch 3 is configured as a dry single-plate friction clutch, and has a flywheel 3A connected to the output shaft 2A of the internal combustion engine 2 and a clutch disk 3B connected to the transmission 4 .

The clutch 3 transmits power between the internal combustion engine 2 and the transmission 4 when the clutch disk 3B is switched to the engaged (connected) state with respect to the flywheel 3A, and is switched to the released (disconnected) state. power transmission between the internal combustion engine 2 and the transmission 4 is interrupted when the

In the vehicle 1 configured as described above, the rotation output from the internal combustion engine 2 is changed at a gear ratio corresponding to the gear stage established by the transmission 4, and is driven through a differential device and a drive shaft (not shown). transmitted to wheel 5;

The accelerator pedal sensor 12A is provided on the accelerator pedal 12 and detects the amount of operation of the accelerator pedal 12 . The brake pedal sensor 13A is provided on the brake pedal 13 and detects the amount of operation of the brake pedal 13 . The clutch pedal sensor 14A is provided on the clutch pedal 14 and detects the amount of operation of the clutch pedal 14 . Here, the amount of operation of each pedal is the amount of depression by the driver, and the greater the amount of depression, the greater the amount of operation. The brake pedal sensor 13A may detect the oil pressure of the master cylinder connected to the brake pedal 13 (master cylinder pressure) instead of the amount of depression of the brake pedal 13 . Hereinafter, the depression amount of the brake pedal 13 or the master cylinder pressure will be referred to as a brake operation amount.

A vehicle speed sensor 15 is provided on the drive wheel 5 and detects the vehicle speed based on the rotational speed of the drive wheel 5 . Acceleration sensor 16 detects the acceleration and attitude of vehicle 1 .

The internal combustion engine 2 is a bi-fuel internal combustion engine that can be used by switching between a first fuel and a second fuel of different types. Therefore, the vehicle 1 is a bi-fuel automobile. The first fuel is gaseous CNG (Compressed Natural Gas). The second fuel is gasoline, which is a liquid fuel. The internal combustion engine 2 is not limited to CNG and gasoline, and may be configured to be able to switch between and use a plurality of types of fuel with different fuel characteristics.

The vehicle 1 includes a first fuel storage portion 8 (referred to as "fuel 1" in FIG. 1) that stores a first fuel, and a second fuel storage portion 9 (referred to as "fuel 2" in FIG. 1) that stores a second fuel. ”). The first fuel, which is CNG, is injected into the intake path by an injector (not shown) for gaseous fuel. A first fuel, which is gasoline, is injected into an intake passage or a combustion chamber by an injector (not shown) for liquid fuel.

The vehicle 1 includes a fuel switching device 7 for switching the fuel to be supplied to the internal combustion engine 2 to the first fuel or the second fuel, and a fuel selection switch 18 for the driver to select the fuel to be used. The fuel selected by the used fuel selection switch 18 is supplied to the internal combustion engine 2 via the fuel switching device 7 .

The vehicle 1 includes a start switch 19 for the driver to start the internal combustion engine 2 . The start switch 19 includes an ignition key for starting the internal combustion engine 2 by rotating the key, and a start button for starting the internal combustion engine 2 by pressing the key.

The ECU 11 includes a computer unit having a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an input port, and an output port. Control the target electrically.

The ROM of the ECU 11 stores a program for causing the computer unit to function as the ECU 11 along with various control constants, various maps, and the like. The computer unit functions as the ECU 11 when the CPU of the ECU 11 executes a program stored in the ROM.

Input ports of the ECU 11 are connected to the internal combustion engine 2, various sensors such as an accelerator pedal sensor 12A, a brake pedal sensor 13A, a clutch pedal sensor 14A, a vehicle speed sensor 15, an acceleration sensor 16, a fuel selection switch 18, and a start switch. 19 are electrically connected.

Control targets such as the internal combustion engine 2, the starter 6, and the fuel switching device 7 are connected to the output port of the ECU 11. FIG. The ECU 11 controls the control target connected to the output port based on detection signals from sensors and the like input to the input port.

In this embodiment, the ECU 11 includes a control section 11A, and the control section 11A automatically stops the internal combustion engine 2 when a predetermined automatic stop condition is satisfied. Further, the control unit 11A restarts the internal combustion engine 2 when a predetermined restart condition is satisfied while the internal combustion engine 2 is automatically stopped. Thus, the control unit 11A of the ECU 11 performs so-called idling stop control for automatically stopping and restarting the internal combustion engine 2. FIG.

Here, the first fuel, which is CNG, has the characteristic of being able to reduce emissions compared to the second fuel, which is gasoline. Therefore, it is preferable to use the first fuel as the fuel for the internal combustion engine 2 in order to reduce emissions.

On the other hand, the first fuel, which is CNG, has the characteristic of having a higher ignition point than the second fuel, which is gasoline. Therefore, the first fuel can ignite (start combustion) only at a temperature higher than that of the second fuel, and the startability of the internal combustion engine 2 is relatively poor. Therefore, when starting the internal combustion engine 2 using the first fuel, it is necessary to crank the internal combustion engine 2 by the starter 6 as a starting device for a long time.

Further, in the internal combustion engine 2 that switches between the first fuel, which is CNG, and the second fuel, which is gasoline, the path from the injector for the first fuel to the combustion chamber extends from the injector for the second fuel to the combustion chamber. Longer than the path to the room. Therefore, the time (starting time) required for starting the internal combustion engine 2 when using the first fuel is longer than the starting time when using the second fuel.

Thus, the first fuel and the second fuel differ in fuel characteristics, fuel supply structure, and the like. As a result, the restartability of the internal combustion engine 2 when using the first fuel is inferior to the restartability of the internal combustion engine 2 when using the second fuel. Here, the restartability is the ease with which the internal combustion engine 2 can be restarted. It can be quantified by the degree of increase in the engine rotation speed after the start of the ranking.

When the internal combustion engine 2, which is a bi-fuel internal combustion engine, uses the second fuel, which is a liquid fuel (gasoline), at each restart, the fuel efficiency is inferior to the first fuel, which is a gaseous fuel (CNG). worsens. Therefore, it is desirable to operate the internal combustion engine 2 using the first fuel in order to improve fuel efficiency, but the first fuel has a higher ignition point and is therefore inferior to the second fuel in restartability. have characteristics.

When the internal combustion engine 2 is restarted using the first fuel, restartability is inferior to that of the second fuel. may decrease, or the starter 6 may wear out. Therefore, it is desirable to suppress the deterioration of the state of charge of the battery and the consumption of the starter 6 when the internal combustion engine 2 is restarted using the first fuel during idle stop.

Therefore, in the present embodiment, when the internal combustion engine 2 is restarted using the first fuel due to the establishment of the restart condition, the control unit 11A of the ECU 11 determines whether the predetermined restart interruption condition is established during the restart. Determine presence/absence. In other words, when restarting the internal combustion engine 2 during idle stop using the first fuel, the control unit 11A determines whether or not the restart interruption condition is satisfied. Then, when the restart interruption condition is satisfied, the control unit 11A interrupts the restart, switches to the second fuel, and restarts the restart. It should be noted that "when the internal combustion engine 2 is restarted using the first fuel due to the establishment of the restart condition" means that the internal combustion It refers to restarting of the engine 2, and does not include restarting after switching to the second fuel (restarting after interruption).

When interrupting the restart and switching the fuel to be used, the control unit 11A may notify the driver that the fuel will be switched to the second fuel. In addition, it has a learning unit that records the fuel used, temperature, and atmospheric pressure when the restart is interrupted and the fuel used is switched. You may make it select at times.

Further, in the case where "interruption" of restart from idle stop is treated as "engine stop", the restart process after engine stop is executed when the driver performs a start operation. Therefore, in such a control mode, the control unit 11A performs restart on the condition that the driver has performed the starting operation after interrupting the restart, and switches to the second fuel prior to the restart. good too.

Further, in the present embodiment, the control unit 11A does not determine whether or not the restart interruption condition is satisfied when restarting is performed using the second fuel due to the establishment of the restart condition.

Further, in the present embodiment, the restart interruption condition is that the engine rotation speed is less than a predetermined rotation speed after the first predetermined time has elapsed from the start of the restart (cranking), or that the restart (cranking) elapse of the second predetermined time without reaching self-sustaining rotation from the start of the rotation. Therefore, when the engine rotation speed does not increase smoothly during cranking, or when the internal combustion engine 2 does not rotate independently even though cranking is performed for a long time, the restart interruption condition is satisfied.

Further, in this embodiment, the restart interruption condition is set according to the type of fuel. That is, in the present embodiment, since the internal combustion engine 2 can be used by switching between the first fuel and the second fuel, which are different in fuel type, the restart interruption condition is set to a condition that matches either the first fuel or the second fuel. If the restart interruption condition is set without considering the fuel type, or if the restart interruption condition is set common to the first fuel and the second fuel, restart The timing at which the start interruption condition is satisfied may be too early or too late than the appropriate timing. Therefore, in the present embodiment, since the target for determining whether or not the restart interruption condition is satisfied is the restart when the fuel type is the first fuel, the restart interruption condition is the ignition point or the like of the first fuel. Conditions are set according to fuel characteristics. In the second embodiment, which will be described later, whether or not the restart interruption condition is satisfied is determined for both restarts when the fuel type is the first fuel and when the fuel type is the second fuel. In addition to the restart interruption condition according to the fuel type for the fuel, the restart interruption condition according to the fuel type for the second fuel is also set. The restart interrupt condition for the first fuel and the restart interrupt condition for the second fuel are different from each other.

Further, in this embodiment, the control unit 11A uses the fuel that was used at the time of automatic stop at the time of restart. Therefore, for example, if the first fuel is being used at the time of automatic stop, the restart is performed while continuing to use the first fuel.

In addition, if the second fuel is used during automatic stop, restart is performed using the second fuel, and when restarting using the second fuel, normal restart is performed without judging the restart interruption condition. is done.

Next, the operation flow of the vehicle control device according to the present embodiment will be described with reference to the flowchart shown in FIG. FIG. 2 shows the operation of restarting the internal combustion engine 2 from idling stop.

In FIG. 2, the control unit 11A repeatedly determines whether or not the engine is automatically stopped until the engine is automatically stopped (step S1). The automatic engine stop state refers to a state in which the internal combustion engine 2 is automatically stopped by idle stop control.

When the engine is automatically stopped (YES in step S1), the control unit 11A repeatedly determines whether or not the engine restart condition is satisfied until the engine restart condition is satisfied (step S2).

When the engine restart condition is satisfied (YES in step S2), the control unit 11A determines whether or not the fuel used for restarting the internal combustion engine 2 is the first fuel (CNG) (step S3). In this embodiment, the fuel used at the time of automatic stop continues to be used at the time of restart. Therefore, in step S3, if the first fuel was used when the internal combustion engine 2 was automatically stopped, it is determined that the fuel to be used for restarting is the first fuel. Further, in this embodiment, the internal combustion engine 2 uses two types of fuel, the first fuel and the second fuel (gasoline). It is determined which of the second fuels.

When the fuel used for restarting the internal combustion engine 2 is the first fuel (YES in step S3), the control unit 11A supplies the first fuel to the internal combustion engine 2 (step S4), and uses the first fuel. restart is started (step S5). At step S5, the control unit 11A drives the starter 6 to start cranking the internal combustion engine 2. As shown in FIG.

Next, the control unit 11A determines whether or not the restart interruption condition for the used fuel is satisfied during the restart (step S8). In this step S8, the restart interruption condition corresponding to the first fuel, which is the used fuel, is applied. If the restart interruption condition is not satisfied (NO in step S8), the controller 11A ends the current operation.

When the restart interruption condition is satisfied (YES in step S8), the controller 11A interrupts the restart (step S9). At step S9, the control unit 11A suspends cranking of the internal combustion engine 2. FIG. Next, the controller 11A controls the fuel switching device 7 to switch the used fuel to the second fuel (step S10).

Next, the control unit 11A starts (resumes) the restart using the second fuel (step S11), and ends the current operation.

On the other hand, when the fuel used for restarting the internal combustion engine 2 is not the first fuel (NO in step S3), the control unit 11A supplies the second fuel to the internal combustion engine 2 (step S6), Use it to start restarting (step S7) and finish this operation.

As described above, the vehicle control apparatus of this embodiment automatically stops the internal combustion engine 2 when a predetermined automatic stop condition is satisfied, and when a predetermined restart condition is satisfied while the internal combustion engine 2 is automatically stopped. is provided with a control unit 11A for restarting the internal combustion engine 2. Further, the restartability of the internal combustion engine 2 when using the first fuel is inferior to the restartability of the internal combustion engine 2 when using the second fuel.

Then, when the restart condition is satisfied and the restart is performed using the first fuel, the control unit 11A determines whether or not the predetermined restart interruption condition is satisfied during the restart. When the restart interruption condition is satisfied, the control unit 11A interrupts the restart, switches to the second fuel, and restarts the restart.

As a result, when it is difficult to restart using the first fuel with poor startability, the restart interruption condition is satisfied and the restart is interrupted, so restart of the internal combustion engine 2 can be interrupted early.

Here, the switching period in which the fuel is switched from the first fuel to the second fuel is a period in which the internal combustion engine 2 cannot be restarted. Therefore, if the starter 6 continues to be driven even during the fuel switching period in which restart is not possible, the driving time of the starter 6 is increased by the amount of the switching period, and the state of charge of the battery decreases and the starter 6 is consumed. occurs.

Therefore, in this embodiment, the restart is interrupted during the fuel switching period from when the restart interrupting condition is established until switching to the second fuel, and the starter 6 is driven after switching to the second fuel. . As a result, deterioration of the state of charge of the battery and consumption of the starter 6 due to long-time driving of the starter 6 can be suppressed.

Further, in this embodiment, the internal combustion engine 2 can be restarted more reliably by switching the fuel to be used to the second fuel, which is superior in startability to the first fuel. Therefore, deterioration of the state of charge of the battery and consumption of the starter 6 due to long-time driving of the starter 6 can be suppressed.

As a result, when the internal combustion engine 2 is restarted from idling stop, the deterioration of the state of charge of the battery and the consumption of the starter 6 can be suppressed.

Further, in the vehicle control apparatus of the present embodiment, the control unit 11A does not determine whether or not the restart interruption condition is satisfied when restarting is performed using the second fuel due to the establishment of the restart condition.

That is, when the second fuel having excellent restartability is used when the internal combustion engine 2 is restarted from the idle stop, it is not determined whether or not the restart interruption condition is satisfied, and the restart is not interrupted. A normal restart will occur.

As a result, it is possible to prevent the internal combustion engine 2 from prolonging the time until the restart is completed due to the interruption of the restart and from increasing the number of restarts due to the interruption. Consumption of the starter 6 can be suppressed.

Further, in the vehicle control apparatus of the present embodiment, the restart interrupting condition is that the engine rotation speed is less than a predetermined rotation speed when the first predetermined time has elapsed from the start of restart, or at least either one of: elapse of the second predetermined time without reaching self-sustaining rotation.

As a result, it is possible to determine whether or not the restart interruption condition is satisfied based on the engine speed at a predetermined timing during restart or the drive time of the starter 6 from the start of restart. It is possible to accurately determine whether or not the condition is established, and to interrupt the restart at an early stage. Therefore, deterioration of the state of charge of the battery and consumption of the starter 6 due to driving the starter 6 for a long time can be suppressed.

Further, in the vehicle control apparatus of the present embodiment, the restart interruption condition is set according to the type of fuel.

As a result, the restart of the internal combustion engine 2 can be interrupted at an early stage based on the restart condition suitable for the type of fuel. can be suppressed, and the restart can be reliably performed.

Further, in the vehicle control apparatus of the present embodiment, the control unit 11A uses the fuel that was used during the automatic stop during the restart.

As a result, if the first fuel was being used when the internal combustion engine 2 was automatically stopped, the engine is restarted using the first fuel. Then, when the restart interruption condition is satisfied at the time of restart using the first fuel, the restart is restarted after switching to the second fuel. In this case, the next automatic shutdown and restart will be with the second fuel. Therefore, at the timing when the internal combustion engine 2 is automatically stopped and restarted by the idle stop control, it is possible to automatically switch to a fuel with excellent restartability, so the fuel to be used can be switched without impairing the drivability. be able to.

Further, if the second fuel is being used at the time of automatic stop, the second fuel is used to restart the engine. Then, when restarting using the second fuel, a normal restart is performed without judging the restart interruption condition. Therefore, when the second fuel is used at the time of automatic stop, the internal combustion engine 2 is quickly restarted, suppressing deterioration of the state of charge of the battery and exhaustion of the starter 6 due to driving the starter 6 for a long period of time. can.

Next, the operation flow of the vehicle control apparatus according to the second embodiment will be described with reference to the flowchart shown in FIG. In this embodiment, part of the operation of the control section 11A of the ECU 11 is changed in the vehicle 1 having the configuration shown in FIG. In this embodiment, when the restart condition is satisfied and the restart is performed using the second fuel, the control unit 11A controls the Determines whether or not the restart interruption condition is established. If the restart interruption condition is met during the restart using the second fuel, the control unit 11A interrupts the restart, but does not switch the fuel or resume the restart thereafter. Other than this operation, the second embodiment is the same as the first embodiment.

Further, in the present embodiment, the object for determining whether or not the restart interruption condition is met is the restart when the fuel type is the first fuel and when the fuel type is the second fuel. In addition to the restart interruption condition according to the fuel type, the restart interruption condition according to the fuel type for the second fuel is also set.

Note that when the second fuel, which is superior in restartability to the first fuel, is used, the threshold for the restart interruption condition is relaxed, making it difficult for the restart interruption condition to be satisfied. For example, the engine rotation speed threshold for the restart interruption condition when the second fuel is used is set higher than the engine rotation speed threshold for the restart interruption condition when the first fuel is used. The reason for this is that the second fuel has a relatively low ignition point, can ignite (start combustion) at a lower temperature, and has excellent restartability, but the restart interruption condition is met when the second fuel is used. This is because if it is easily established and the restart is frequently interrupted, convenience may deteriorate.

The operation of the control section 11A of the ECU 11 will be described below. FIG. 3 shows the operation of restarting the internal combustion engine 2 from idle stop.

In FIG. 3, the control unit 11A repeatedly determines whether or not the engine is automatically stopped until the engine is automatically stopped (step S21).

When the engine is automatically stopped (YES in step S21), the control unit 11A repeatedly determines whether or not the engine restart condition is satisfied until the engine restart condition is satisfied (step S22).

When the engine restart condition is satisfied (YES in step S22), the control unit 11A determines whether or not the fuel used for restarting the internal combustion engine 2 is the first fuel (CNG) (step S23). In this embodiment, the fuel used at the time of automatic stop continues to be used at the time of restart. Therefore, in step S23, if the first fuel was being used when the internal combustion engine 2 was automatically stopped, it is determined that the fuel to be used for restarting is the first fuel. In this embodiment, the internal combustion engine 2 uses two types of fuel, the first fuel and the second fuel (gasoline). It is determined which of the second fuels.

When the fuel used for restarting the internal combustion engine 2 is the first fuel (YES in step S23), the control unit 11A supplies the first fuel to the internal combustion engine 2 (step S24), and uses the first fuel. restart is started (step S26). At step S26, the control unit 11A drives the starter 6 to start cranking the internal combustion engine 2. As shown in FIG.

On the other hand, if the fuel used for restarting the internal combustion engine 2 is not the first fuel in step S23 (NO in step S23), the control unit 11A supplies the second fuel to the internal combustion engine 2 (step S25), 2 fuel is used to start restarting (step S26).

After starting the restart of the internal combustion engine 2 in step S26, the control unit 11A determines whether or not the restart interruption condition for the used fuel is satisfied during the restart (step S27). In this step S27, if the used fuel is the first fuel, the restart interruption condition corresponding to the first fuel is applied. Further, if the used fuel is the second fuel, the restart interruption condition corresponding to the second fuel is applied. If the restart interruption condition is not satisfied (NO in step S27), the controller 11A ends the current operation.

When the restart interruption condition is satisfied (YES in step S27), the control unit 11A interrupts the restart (step S28). At step S28, the control unit 11A suspends the cranking of the internal combustion engine 2.

Next, the control unit 11A determines whether or not the fuel used at the time of restart interruption is the first fuel (step S29). If the control unit 11A determines in step S29 that the fuel is not the first fuel (if the fuel is the second fuel), the current operation is terminated.

When the controller 11A determines that the fuel is the first fuel in step S29, it controls the fuel switching device 7 to switch the fuel to be used to the second fuel (step S30).

Next, the control unit 11A starts (resumes) the restart using the second fuel (step S31), and ends the current operation.

As described above, in this embodiment, when the restart condition is satisfied and the restart is performed using the second fuel, the control unit 11A determines whether or not the restart interruption condition is satisfied during the restart. Then, the control unit 11A suspends the restart when the restart suspension condition is satisfied.

This prevents restarting (cranking) using the second fuel, which has excellent startability, from continuing for a long time without succeeding in restarting.

As a result, when the internal combustion engine 2 is restarted from idling stop, the deterioration of the state of charge of the battery and the consumption of the starter 6 can be suppressed.

Although embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

1 vehicle 2 internal combustion engine 11 ECU (vehicle control device)
11A control unit

Claims (6)

A control device for a vehicle equipped with an internal combustion engine that switches between a first fuel and a second fuel of different types,
a control unit that automatically stops the internal combustion engine when a predetermined automatic stop condition is satisfied and restarts the internal combustion engine when a predetermined restart condition is satisfied during the automatic stop of the internal combustion engine;
The restartability of the internal combustion engine when using the first fuel is inferior to the restartability of the internal combustion engine when using the second fuel,
The control unit
determining whether or not a predetermined restart interruption condition is satisfied during the restart when the restart is performed using the first fuel due to the satisfaction of the restart condition;
A control device for a vehicle, wherein when the restart interruption condition is satisfied, the restart is interrupted, and the restart is restarted by switching to the second fuel. The control unit
2. The control device for a vehicle according to claim 1, wherein when the restart is performed using the second fuel due to the establishment of the restart condition, it is not determined whether or not the restart interrupt condition is established. The control unit
determining whether or not the restart interruption condition is satisfied during the restart, when the restart is performed using the second fuel due to the satisfaction of the restart condition;
2. A control device for a vehicle according to claim 1, wherein said restart is interrupted when said restart interruption condition is satisfied. The restart interruption condition is that the engine rotation speed is less than a predetermined rotation speed when a first predetermined time has elapsed from the start of the restart, or a second predetermined engine speed without reaching self-sustaining rotation from the start of the restart. 4. The vehicle control device according to any one of claims 1 to 3, wherein at least one of the elapse of time and the elapse of time. 5. The control device for a vehicle according to claim 1, wherein the restart interruption condition is set according to the type of fuel. 6. The control device for a vehicle according to claim 1, wherein the control unit uses the fuel used during the automatic stop during the restart.

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