JP7211015B2 - Vehicle control device for bi-fuel vehicle - Google Patents

Description

The present invention relates to a vehicle control device for a bi-fuel vehicle.

In Patent Document 1, in a bi-fuel engine, a command from a manual switch during operation switches to a gasoline fuel supply valve or a gas fuel supply valve with a signal from an electronic control device, and injects gasoline fuel or gas fuel into an intake pipe. What to do is listed.

JP 2015-17594 A

However, since the fuel is not injected while the engine is automatically stopped, even if the driver performs the fuel switching operation, the fuel switching cannot be performed, and the driver cannot recognize whether the switching operation has been accepted or not, which causes confusion. There was a problem.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a vehicle control device for a bi-fuel vehicle that allows the driver to recognize that the vehicle control device has accepted a fuel switching operation.

In order to solve the above problems, the present invention provides an internal combustion engine, a first fuel supply system that supplies a first fuel to the internal combustion engine, and a second fuel supply system that supplies a second fuel to the internal combustion engine. a fuel switching operation unit for receiving a switching operation of the fuel used in the internal combustion engine; automatically stopping the internal combustion engine when a predetermined automatic stopping condition is satisfied; and when a predetermined restarting condition is satisfied, the a control unit for restarting the internal combustion engine, wherein when a fuel switching operation is input to the fuel switching operation unit during the automatic stop, the control unit restarts the fuel supply used before the automatic stop. The internal combustion engine is restarted using fuel from the same fuel supply system as the system .

Thus, according to the present invention, the driver can be made to recognize that the vehicle control device has accepted the fuel switching operation.

FIG. 1 is a block diagram of a vehicle control system for a bi-fuel vehicle according to one embodiment of the present invention. FIG. 2 is a flow chart showing a procedure of fuel switching control processing of the vehicle control system for a bi-fuel vehicle according to one embodiment of the present invention.

A vehicle control system for a bi-fuel vehicle according to one embodiment of the present invention includes an internal combustion engine, a first fuel supply system that supplies a first fuel to the internal combustion engine, and a second fuel that supplies the internal combustion engine. A second fuel supply system, a fuel switching operation unit that receives a switching operation of the fuel used in the internal combustion engine, and automatically stops the internal combustion engine when a predetermined automatic stop condition is satisfied, and a predetermined restart condition is satisfied. and a control unit for restarting the internal combustion engine when the engine is automatically stopped, and the control unit is configured to restart the internal combustion engine when a fuel switching operation is input to the fuel switching operation unit during automatic stop. .

As a result, the vehicle control device for the bi-fuel vehicle according to the embodiment of the present invention can make the driver aware that the vehicle control device has accepted the fuel switching operation.

A vehicle control system for a bi-fuel vehicle according to an embodiment of the present invention will now be described in detail with reference to the drawings.

In FIG. 1, a bi-fuel vehicle (hereinafter also simply referred to as "vehicle") 1 equipped with a vehicle control system for a bi-fuel vehicle according to one embodiment of the present invention includes an engine 2 as an internal combustion engine and a transmission 3. , and an ECU (Electronic Control Unit) 8 as a control unit.

A plurality of cylinders are formed in the engine 2 . In this embodiment, the engine 2 is constructed so that each cylinder performs a series of four strokes consisting of an intake stroke, a compression stroke, an expansion stroke and an exhaust stroke.

A starter 21 is connected to the engine 2 . Starter 21 is connected to the crankshaft of engine 2 . The starter 21 rotates when supplied with electric power, thereby rotating the crankshaft and giving the engine 2 a rotational force for starting.

The engine 2 is supplied with one selected from two types of fuel, gasoline as a first fuel and CNG (Compressed Natural Gas) as a second fuel, as fuel to be injected into the combustion chamber of each cylinder. be. The engine 2 has a first fuel supply system that supplies gasoline stored in the gasoline tank 4 into the combustion chamber, and a second fuel supply system that supplies CNG stored under high pressure in the gas fuel tank 5 into the combustion chamber. It has

A first fuel supply system includes a gasoline tank 4 and a gasoline injector 41 . The gasoline injector 41 injects gasoline into the combustion chamber of each cylinder of the engine 2 .

The second fuel supply system includes a gas fuel tank 5 and gas fuel injectors 51 . The gas fuel injector 51 injects CNG into the combustion chamber of each cylinder of the engine 2 .

A fuel supply system that supplies fuel into the combustion chamber of each cylinder of the engine 2 is switched between a first fuel supply system and a second fuel supply system under the control of the ECU 8 .

The transmission 3 changes the speed of the rotation output from the engine 2 to drive the drive wheels 10 via the drive shaft 11 . The transmission 3 includes a constant-mesh transmission mechanism (not shown) consisting of a parallel shaft gear mechanism. The transmission 3 selects a gear stage in the transmission mechanism according to the operation of a shift lever (not shown) by the driver.

The transmission 3 is, for example, a shift state of 1st speed to 5th speed corresponding to a predetermined gear ratio, a neutral state in which the rotation output from the engine 2 is not transmitted to the drive shaft 11, and a vehicle 1 shift state, depending on the operation of the shift lever. take one of the reverse states for moving backward.

A dry single-plate clutch 31 , for example, is provided between the engine 2 and the transmission 3 , and the clutch 31 connects or disconnects power transmission between the engine 2 and the transmission 3 .

The state transition between the connected state and the disconnected state of the power transmission in the clutch 31 corresponds to the depressed position of the clutch pedal 81, that is, the clutch stroke.

When the clutch pedal 81 is not depressed, the clutch 31 is engaged and the rotation of the crankshaft is transmitted to the transmission 3 .

On the other hand, when the clutch pedal 81 is depressed, the clutch 31 is disengaged and power transmission from the crankshaft to the transmission 3 is cut off.

A clutch pedal switch 82 is provided on the clutch pedal 81 . A clutch pedal switch 82 detects whether or not the clutch 31 is in a disengaged state.

The ECU 8 is a computer having a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory for storing backup data, an input port, and an output port. made up of units.

In the ROM of this computer unit, various constants, various maps, etc., and a program for causing the computer unit to function as the ECU 8 are stored.

That is, the computer unit functions as the ECU 8 in this embodiment by the CPU executing a program stored in the ROM using the RAM as a work area.

In addition to the above-described clutch pedal switch 82, the input port of the ECU 8 is equipped with various sensors such as a fuel selection switch 9 as a fuel switching operation unit, an accelerator opening sensor 84, a brake switch 86, a vehicle speed sensor 87, a water temperature sensor 88, and the like. is connected.

A fuel selection switch 9 receives a driver's operation and outputs a signal for selecting either gasoline or CNG as the fuel to be injected into the combustion chamber of each cylinder of the engine 2 . The ECU 8 switches the fuel to be injected into the combustion chamber of each cylinder of the engine 2 according to the signal from the fuel selection switch 9 to be used.

The accelerator opening sensor 84 detects the accelerator opening, which is the opening of the accelerator pedal 83 operated by the driver. A brake switch 86 detects whether or not the brake pedal 85 has been depressed by the driver. A vehicle speed sensor 87 detects the speed of the vehicle 1 from the rotational speed of the driving wheels 10 and the like. A water temperature sensor 88 detects the temperature of cooling water for the engine 2 .

On the other hand, the output port of the ECU 8 is connected to various control objects including the starter 21, the gasoline injector 41, and the gas fuel injector 51 described above. By controlling the starter 21, the gasoline injector 41, and the gas fuel injector 51, the ECU 8 controls starting and stopping of the engine 2, output torque, and the like.

The ECU 8 controls an idling stop function that stops the engine 2 when a preset automatic stop condition is satisfied and restarts the engine 2 when a preset restart condition is satisfied.

The automatic stop conditions include, for example, that the vehicle speed is equal to or less than a predetermined vehicle speed, that the transmission 3 is in a neutral state, that the brake pedal 85 is depressed, that the clutch pedal 81 is not depressed, and that the accelerator pedal 81 is not depressed. The condition is that all conditions such as that the degree of opening is equal to or less than a predetermined degree of opening are satisfied. On the other hand, the restart condition is, for example, that either the clutch pedal 81 is depressed or the brake pedal 85 is not depressed while the transmission 3 is in the neutral state.

The ECU 8 restarts the engine 2 when an operation for switching the fuel is input to the fuel selection switch 9 while the automatic stop condition is satisfied and the engine 2 is automatically stopped.

When the ECU 8 restarts the engine 2 by inputting a fuel switching operation to the used fuel selection switch 9 while the engine 2 is automatically stopped due to the establishment of the automatic stop condition described above, the fuel is switched. Instead, the engine 2 is restarted using the same fuel supply system that was used before the automatic stop.

The first fuel supply system and the second fuel supply system cannot detect any abnormality unless the fuel injection device is stuck closed, unless the system is in operation. In addition, the fuel supply system that was used before the automatic stop has already detected an abnormality in the same driving cycle, and the possibility of an abnormality is low compared to the fuel supply system that was not used.

For this reason, during automatic stop, the fuel used is not switched according to the driver's instructions, and the possibility of starting failure and engine stall when restarting due to an abnormality in the fuel supply system after switching is prevented. .

Further, the fuel is switched during the automatic stop, and an abnormality in the fuel supply system after the switching is detected during the restart of the engine 2. If an abnormality is detected in the fuel supply system after switching, the fuel In the case of a configuration that returns to the fuel before switching, even if an abnormality in the fuel supply system after switching is detected during restarting, the engine speed during restarting is lower than during running, and the fuel before switching is used. There was a possibility that the restart would fail and the engine would stall before returning to fuel. It should be noted that when the fuel is switched while the vehicle is running, the number of rotations of the engine 2 is a certain number or more, and even if an abnormality in the fuel supply system is detected after the fuel is switched, the engine stalls. It is possible to return to the fuel supply system before switching before the number of revolutions is reached.

For these reasons, during the automatic stop, the fuel used is not switched according to the driver's instructions, and the engine 2 is started using the same fuel supply system fuel that was used before the automatic stop. By restarting the engine, an abnormality in the fuel supply system after switching can prevent the engine from stalling due to starting failure at the time of restarting.

Also, after the engine 2 is restarted, the fuel may be switched. However, even if an abnormality is detected in the fuel supply system after switching, the condition for switching may be that the engine speed reaches a level at which the fuel can be returned to the fuel before switching without engine stall.

After the engine 2 is restarted, for example, automatic stop of the engine 2 by idling stop is prohibited until the vehicle speed reaches or exceeds a predetermined speed. By doing so, it is possible to suppress the repetition of the idling stop while the vehicle is stopped, and to prevent the driver from being confused.

As another example, the ECU 8 may be configured such that when an operation for switching the fuel is input to the fuel selection switch 9 when the automatic stop condition described above is satisfied and the engine 2 is automatically stopped, If no abnormality is detected in the fuel supply system that was not used before the automatic stop, switch the fuel and restart the engine 2 using the fuel in the fuel supply system that was not used before the automatic stop. If an abnormality is detected in the fuel supply system that was not used before the automatic stop, the engine 2 may be restarted using the same fuel in the fuel supply system that was used before the automatic stop.

A fuel switching control process performed by the vehicle control apparatus for a bi-fuel vehicle according to the present embodiment configured as described above will be described with reference to FIG. Note that the fuel switching control fuel processing described below is started when the engine 2 is automatically stopped by idling stop, and is executed at preset time intervals.

In step S<b>1 , the ECU 8 determines whether or not the fuel switching instruction is given by the driver by operating the fuel selection switch 9 . When determining that there is no fuel switching instruction from the driver, the ECU 8 terminates the process.

If it is determined that the driver has issued a fuel switching instruction, the ECU 8 starts the engine 2 in step S2 and terminates the process.

As described above, in the above-described embodiment, the engine 2 is restarted when the operation for switching the fuel is input to the fuel selection switch 9 while the engine 2 is automatically stopped.

This makes it possible for the driver to recognize that the vehicle control device has accepted the fuel switching operation, thereby preventing the driver from being unable to recognize whether the fuel switching operation has been accepted.

In addition, by restarting the engine 2, the driver can check whether the fuel switching operation has been received during the automatic stop when the vehicle is stopped on a public road by a traffic signal or a road sign such as a stop sign. While keeping an eye on the direction of movement of the vehicle, the vibration and sound of restarting can be used to safely and reliably recognize the vehicle.

Further, when the operation of fuel switching is input to the fuel selection switch 9 while the engine 2 is automatically stopped, the engine 2 is started using the same fuel supply system used before the automatic stop. restart.

As a result, the engine 2 can be reliably restarted by preventing starting failure at the time of restarting, so that the driver's inability to recognize whether or not the fuel switching operation has been accepted can be suppressed.

In addition, when the operation of fuel switching is input to the fuel selection switch 9 during automatic stop of the engine 2, if no abnormality is detected in the fuel supply system that was not used before automatic stop, before automatic stop If the engine 2 is restarted using the fuel in the fuel supply system that was not used and an abnormality is detected in the fuel supply system that was not used before the automatic stop, the fuel that was used before the automatic stop is detected. The engine 2 may be restarted using fuel from the same fuel supply system as the fuel supply system.

As a result, the fuel is switched only when no abnormality is detected in the fuel supply system of the switching destination. It is possible to suppress things that people cannot perceive.

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 bi-fuel vehicle 2 engine (internal combustion engine)
4 gasoline tank 5 gas fuel tank 8 ECU (control unit)
9 Used fuel selection switch (fuel switching operation part)
41 petrol injector 51 gas fuel injector

Claims (2)

an internal combustion engine;
a first fuel supply system that supplies a first fuel to the internal combustion engine;
a second fuel supply system that supplies a second fuel to the internal combustion engine;
a fuel switching operation unit that receives a fuel switching operation for use in the internal combustion engine;
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;
When a fuel switching operation is input to the fuel switching operation unit during the automatic stop, the control unit uses the fuel of the same fuel supply system as the fuel supply system used before the automatic stop. A vehicle control device for a bi-fuel vehicle that restarts an internal combustion engine. an internal combustion engine;
a first fuel supply system that supplies a first fuel to the internal combustion engine;
a second fuel supply system that supplies a second fuel to the internal combustion engine;
a fuel switching operation unit that receives a fuel switching operation for use in the internal combustion engine;
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;
When a fuel switching operation is input to the fuel switching operation unit during the automatic stop, the control unit detects that no abnormality is detected in the fuel supply system of the switching destination, the fuel being used before the automatic stop. The internal combustion engine is restarted using the fuel in the fuel supply system that was not used, and if an abnormality is detected in the fuel supply system of the switching destination, the same fuel as in the fuel supply system used before the automatic stop A vehicle control device for a bi- fuel vehicle that restarts the internal combustion engine using fuel from a supply system.

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