JPH06239166A - Method and device for indicating malfunction of vehicle - Google Patents

Abstract

PURPOSE: To communicate a clear trouble state indication to a driver by an appropriate emergency driving mode for the driver to go to a service garage for fixing the problem. CONSTITUTION: An apparatus for indicating trouble of a vehicle is provided with a control unit 120 for adjusting the output of the engine of the vehicle and a device 155 for identifying a state of trouble. When the occurrence of a state of trouble is detected by the trouble identifying device, the output power of an internal combustion engine 100 is reduced by the control unit. In this case, the amount by which the output is reduced is increased as a function of driving time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a method and apparatus for indicating a vehicle failure, and more particularly, a control unit for adjusting the engine output of the vehicle and means for detecting a failure condition.
The present invention relates to a vehicle failure display method and device in which a control unit reduces output when a failure occurs.

[0002]

2. Description of the Related Art A method of this kind for a vehicle fault indication and a device of this kind are known from DE-OS 3731109. There, the output of the vehicle is reduced in order to give a fault indication. Therefore, the transmission characteristic between the accelerator pedal and the member that determines the output is changed so that a considerably large amount of idling occurs when the accelerator pedal is operated when a failure is detected. This means that when the driver lightly operates the accelerator pedal, the reaction of the internal combustion engine cannot be felt.

Furthermore, it is known to use warning lamps to indicate a fault condition. The driver pays little attention to the warning light, whether intentionally or not. This is because, for example, even if a warning lamp is turned on, it is not noticeable or its function is unknown. If the warning lamp fails, the warning will be disabled.

If the maximum possible total load is simply reduced by a constant value, the choice of this reduction is problematic. If a very small reduction is selected and the driver seldom utilizes the full engine power, then the driver will usually only be able to see a slight reduction in the total load after a considerable period of time. It is noticeable. On the other hand, if it is significantly restricted, in some cases it will stop immediately. This is because, for example, a sufficient output cannot be obtained when the load is high.

[0005]

SUMMARY OF THE INVENTION It is therefore an object of the invention to provide a vehicle fault indication method and device of the type mentioned at the outset such that the driver can go to a repair shop to correct the fault by corresponding emergency travel processing. This is to give the driver a clear failure status display.

[0006]

In order to solve the above-mentioned problems, the present invention comprises a control unit for adjusting the engine output of a vehicle and a means for identifying a failure state,
In a vehicle failure display method and device in which a control unit reduces the generated output when a failure occurs, a configuration is adopted in which the amount by which the generated output is reduced by a predetermined amount increases as a function of operating time.

[0007]

The method or device according to the invention has the advantage that in the event of a fault, a warning is given by interfering with the normal driving behavior or driving characteristics of the vehicle. This ensures that the fault is detected by the driver. In that case, it is an advantage that the driver always looks for a repair shop and the vehicle can go to the repair shop by himself. The method and apparatus of the present invention is particularly suitable for indicating a fault that would otherwise cause a vehicle to be stranded.

In the preferred embodiment, the amount of decrease increases linearly with time. The increase in the decrease amount can be large at the beginning or can be small. Also,
The function that raises the reduction can be related to the type of failure.

In the self-ignition type internal combustion engine, the maximum allowable injection amount is reduced in order to reduce the generated output.

Further, the reduction amount can be reduced for a short period depending on the operating condition.

Moreover, the amount of reduction increases over a selectable period of 5 to 10 operating hours. In this case, the reduction amount is the first
At the stage of, the value rises dramatically to the first value, rises according to the continuous function for a predetermined period, and is maintained at this value after reaching the predetermined value.

[0012]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

In the following, the method of the present invention and the apparatus of the present invention will be described with reference to an example of a vehicle equipped with a self-ignition type internal combustion engine (diesel engine). The present invention is not limited to self-ignition internal combustion engines. The invention can also be used in other internal combustion engines, in particular external ignition internal combustion engines. In that case, the corresponding components must be replaced. That is, for example, a throttle valve is used instead of the control rod (control rack).

FIG. 1 shows a block diagram of the device of the present invention. Reference numeral 100 denotes an internal combustion engine,
Its output power is determined via the output-defining member 110. In this case, the member which determines the output is preferably a control rod or a member which functions in the same manner in the self-ignition type internal combustion engine. In a solenoid valve control system, for example, a solenoid valve having a corresponding output stage.

A corresponding signal is supplied from the control unit 120 to the member 110 defining this output. The control unit 120 processes various signals, in particular the output signal of a speed sensor 122 arranged on the internal combustion engine or on the crankshaft and / or the camshaft or an associated shaft.

In addition, the controller 120 processes signals related to the accelerator pedal position of the accelerator pedal position sensor 125. Further, various signals of the device 130 are transmitted to the control device 12.
Supplied to zero. The device 130 has other sensors that detect various operating conditions. But again, the device 130
Can be a system for exchanging information, in particular an interface with a so-called BUS. Various control devices, sensors and actuators exchange data with each other via this BUS.

The control unit 120 consists essentially of the following elements: A central unit 150, which is preferably embodied as a microprocessor, comprises a rotational speed sensor 122 and an accelerator pedal position sensor 12.
5 and device 130 signals.

The central unit has in particular a fault detection device 155. A fuel quantity signal Q is supplied by the central unit to the minimum value selection device 135 and a signal to the limiting means 140. The fault detection device also supplies a signal to the limiting means 140. The limiting means 140 determines the maximum allowable injection amount QMA.
X is supplied to the minimum value selection device 135. The minimum selector 135 selects the smaller of the two signals and feeds that signal to the element 110 defining the output.

The function of this type of control unit is especially
-OS3531198 (US-A4791900). This publication also particularly describes the failure detection device 155. Therefore, in the following, the function of the control unit will be described briefly.

The central unit 150 calculates a signal for driving a member whose output is determined on the basis of the driver's demand, the rotational speed and various other operating conditions detected via the accelerator pedal position sensor 125. This signal corresponds approximately to the fuel quantity to be injected. Particularly in the case of a diesel internal combustion engine, this fuel amount Q is the maximum allowable injection amount QMAX.
Being restricted to. This maximum allowable injection amount QM
AX mainly relates to various operating conditions such as the number of revolutions. This value is set by the limiting means 140.

According to the present invention, a signal is supplied from the fault detection device 155 to the limiting means 140, and based on the signal, the limiting means 140 changes the maximum allowable injection amount QMAX according to the present invention. Preferably, the fault detection device determines the amount by which the limiting means 140 has to reduce the maximum permissible injection quantity QMAX by a predetermined amount and supplies a corresponding signal to the limiting means. However, at the time of failure, the failure detection device sets the maximum allowable injection amount in the limiting means, and the limiting means selects the minimum value as the maximum allowable injection amount QMAX using the signal set by the failure detection device instead of the normal full load limit value. It is also possible to supply to the device 135. How the maximum permissible injection quantity QM after a fault is identified
As to whether AX is changed as a function of operating time,
This will be described below with reference to FIG.

FIG. 2 shows various fuel quantity values for the operating time t. The QLL shows the idling amount required to maintain the idling speed. QVL is the normal full load range. This value has a certain bandwidth. This value is usually related to various operating parameters. What is shown by the solid line is the maximum allowable injection amount transmitted from the failure detection device to the limiting means 140.

Until time T0, this value is the normal total load Q.
It exceeds VL. This means that the limiting means 140 sets the maximum allowable injection amount QMAX within the range of almost the full load amount QVL. When the fault is detected by the fault detection device 155 at time T0, the maximum allowable injection amount is
It is reduced to a first value W1 which is smaller than the total load. This change is dramatic. Subsequently, in the period between T0 and T1, the maximum allowable injection amount QMAX is reduced according to a continuous function.

This reduction takes place over a relatively long, selectable period of about 5 to 10 (running) hours. After this period, the maximum allowable injection amount QMAX is the idling amount Q
It is kept at a constant value W2 which is greater than LL. Preferably the length of said period is related to the severity of the failure. In the case of relatively minor failures, the reduction takes place over a relatively longer period than in the case of major failures.

The first value W1 at which the maximum permissible injection quantity QMAX drops drastically there corresponds to a value that the driver reaches only under full load conditions, this value W1 being a value that is rarely reached under normal driving methods. Is. Maximum allowable injection amount QMAX
The second constant value W2 at which is maintained constant corresponds to the fuel quantity which allows only a very limited running operation.

The reduction of the maximum permissible injection quantity QMAX preferably takes place linearly with respect to time. This means that the amount that decreases the maximum allowable injection amount by the predetermined amount increases linearly with time.

However, it is also possible to choose a gradual or progressive reduction of the fuel quantity. This is shown in FIG.
This means that the decrease is relatively slow at the beginning of the period and rapid at the end of the period, as indicated by the dashed line in (a).

On the other hand, it is shown by the dotted line that the decrease is very rapid at the beginning and then only fairly slowly thereafter. Preferably, the function that decreases the maximum allowable injection amount QMAX or the amount that decreases the maximum allowable injection amount QMAX is related to the type or severity of the failure. Thus, for example, in the case of more serious failures, the maximum permissible injection quantity is reduced very rapidly at the beginning.

In the case of a slight failure, the maximum allowable injection amount Q
MAX can be reduced very slowly at the beginning. In addition, in the case of a minor failure,
The period before reducing the maximum allowable injection amount QMAX can be correspondingly selected to be large.

Another preferred embodiment is illustrated in FIG. 2 (b). If a running state occurs while the maximum allowable injection amount is decreasing, the maximum allowable injection amount QMAX
The amount to reduce is withdrawn for a short period. This type of driving situation exists, for example, when the driver suddenly desires a higher output, for example to pass another vehicle.

Preferably the accelerator pedal change rate and / or
Alternatively, this type of increase occurs when the accelerator pedal position exceeds a predetermined threshold value. This type of increase is commonly referred to as the kickdown function.

As shown in FIG. 2 (b), the driver is at time T
2 wants more output. At this point, the limiting means 140
Cancels the decrease in the maximum allowable injection amount. This means that the amount that decreases the maximum allowable injection amount is preferably returned to the first value W1. Then, at time T3, the maximum allowable injection amount is returned to the value corresponding to this time again very rapidly. This allows the driver to overcome certain critical driving situations even with a defective vehicle.

In the preferred embodiment of the invention, the maximum permissible injection quantity QMAX is not reduced by a predetermined value related to the operating time, but rather the fuel quantity Q to be injected is reduced by a corresponding quantity. You can also

[0034]

As is apparent from the above description, according to the present invention, when a failure occurs, a warning is given by interfering with the normal running operation or running characteristics of the vehicle, thereby ensuring the failure. When detected by the driver, the driver always searches for a repair shop, and the vehicle can be driven to the repair shop by itself.

[Brief description of drawings]

FIG. 1 is a block circuit diagram showing a configuration of a device of the present invention.

FIG. 2 is a diagram illustrating the method of the present invention.

[Explanation of symbols]

 100 Internal Combustion Engine 120 Control Unit 140 Limiting Means 155 Failure Detection Device

Claims (10)

[Claims] 1. A vehicle failure display method, comprising: a control unit for adjusting an engine output of a vehicle; and a means for identifying a failure state, wherein the control unit reduces the generated output when a failure occurs. A method for indicating a vehicle failure, characterized in that the amount by which the generated output is reduced by that amount rises as a function of operating time. 2. Method according to claim 1, characterized in that the quantity rises linearly with time. 3. Method according to claim 1, characterized in that the increase in the quantity is large at the beginning. 4. Method according to claim 1, characterized in that the increase in the quantity is slight at the beginning. 5. The method according to claim 1, wherein the function increasing the quantity is related to the type of failure. 6. The method according to claim 1, wherein the maximum permissible injection quantity is reduced in order to reduce the output power in a self-igniting internal combustion engine. 7. The method according to claim 1, wherein the quantity can be reduced in a short period of time according to operating conditions. 8. The method according to claim 1, wherein the quantity is increased over a selectable period of 5 to 10 operating hours. 9. The quantity jumps dramatically to a first value in a first step and rises according to a continuous function for a predetermined period,
9. A method as claimed in any one of the preceding claims, characterized in that after reaching a predetermined value it is maintained at this value. 10. A vehicle failure display device, comprising: a control unit for adjusting an engine output of a vehicle; and a means for identifying a failure state, wherein the control unit reduces the generated output when a failure occurs. A failure display device for a vehicle, comprising means for setting an amount by which the generated output is reduced by that amount so as to increase as a function of operating time.