JPH0893587A - Fuel level warning device for vehicles - Google Patents

Abstract

(57) [Summary] (Correction) [Purpose] To provide a vehicle fuel level warning device that re-warns the driver that the fuel level is low even after the fuel pump is restarted. Constitution: When the fuel reaches a predetermined position (step 1), the central processing unit stops the fuel pump (step 2), while the fuel pump stopped by the pump restart switch can be restarted (steps 3, 4). ), The central processing unit counts the ignition signal from the igniter or the shaft rotation signal from the vehicle speed sensor when the fuel pump is first stopped, and the number of signals reaches a predetermined value. At this time, the central processing unit is configured to limit the operation of the engine (step 5).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle fuel level warning device.

[0002]

2. Description of the Related Art Some vehicles are equipped with means for issuing a warning to a driver when the amount of fuel in a fuel tank falls below a prescribed amount.

As a means for this, for example, a float is floated on the fuel in the fuel tank, and the vertical movement of the float associated with the consumption or replenishment of the fuel is mechanically or electrically detected to operate the fuel gauge, and the driver is informed. There is something to inform you of the remaining fuel amount.

Further, as another means, for example, there is one in which a fuel sensor is provided in the fuel tank. This fuel sensor utilizes changes in the resistance value of the thermistor due to temperature.The thermistor is fixed at a predetermined liquid level in the fuel tank, and the temperature difference between liquid and air in the thermistor is detected as the resistance value. However, when the fuel reaches a predetermined liquid level, for example, the fuel pump is stopped to shut off the fuel supply to the engine to warn the driver that the fuel level is low. . In this means, the driver restarts the fuel pump to enable traveling until refueling.

[0005]

However, even though the fuel pump is stopped because the fuel in the fuel tank is low and the driver is warned that the fuel level is low, the driver restarts the fuel pump. You may forget to start it. Then, if the vehicle is run for a long time while the fuel pump is restarted, the fuel will run out unexpectedly.

The present invention has been made in consideration of the above-mentioned circumstances, and provides a vehicle fuel remaining amount warning device which re-warns the driver that the fuel remaining amount is low even after the fuel pump is restarted. The purpose is to

[0007]

In order to solve the above-mentioned problems, a vehicle fuel level warning device according to the present invention comprises a thermistor at a predetermined position in a fuel tank as described in claim 1. An electric tachometer or an engine for calculating the engine speed by an ignition signal from an igniter provided on the crankshaft of the engine, which has a fuel sensor and a fuel pump for supplying the fuel in the fuel tank to the engine. At least one of the electric speedometer that calculates the vehicle speed by the shaft rotation signal from the vehicle speed sensor provided on the output shaft of the, while the central processing unit stops the fuel pump when the fuel reaches the predetermined position, In a vehicle configured to restart the above fuel pump stopped by the pump restart switch The central processing unit counts the ignition signal from the igniter or the shaft rotation signal from the vehicle speed sensor from the time the fuel pump is first stopped, and when the number of signals reaches a predetermined value, the central processing unit Is configured to limit the operation of the engine.

[0008]

According to the present invention having the above-mentioned structure, the engine has a fuel sensor having a thermistor at a predetermined position in the fuel tank, and a fuel pump for supplying the fuel in the fuel tank to the engine. At least one of an electric tachometer that calculates the engine speed by an ignition signal from an igniter provided on the shaft or an electric speedometer that calculates the vehicle speed by a shaft rotation signal from a vehicle speed sensor provided on the output shaft of the engine. The central processing unit of a vehicle configured to restart the fuel pump stopped by a pump restart switch while the central processing unit stops the fuel pump when the fuel reaches the predetermined position. From the above igniter since the fuel pump was first stopped When the fire signal or the shaft rotation signal from the vehicle speed sensor is counted and the central processing unit is configured to limit the operation of the engine when the number of signals reaches a predetermined value, the driver restarts the fuel pump. Even if the driver forgets to start the vehicle, normal running of the vehicle becomes difficult due to the limitation of the operation of the engine, and the driver can be re-warned that the remaining fuel amount is low.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing an example of a vehicle fuel remaining amount warning device to which the present invention is applied, and FIG. 2 shows a first embodiment of an operating procedure of the vehicle fuel remaining amount warning device. It is a flowchart. As shown in FIG. 1, a fuel sensor 2 including a thermistor 1 is provided in a fuel tank (not shown), and the thermistor 1 is arranged at a preset reserve surface position. The signal from the thermistor 1 is sent through the input circuit 3 to the central processing unit Central Proc.
It is input to the essing Unit 4 (hereinafter referred to as CPU).

As shown in FIG. 2, the CPU 4 determines whether the fuel in the fuel tank has reached the reserve surface (step 1). If it is determined that the fuel has reached the reserve surface,
The operation of the fuel pump 6 that supplies fuel to the engine (not shown) via the pump drive circuit 5 is stopped, thereby notifying the driver that the engine has stopped and the fuel has reached the reserve surface (step 2). In addition, the fuel pump 6 whose start has been stopped has a pump restart switch 7
It can be restarted by turning ON (step 3) (step 4).

The vehicle is equipped with a tachometer 8 and a speedometer 9. The tachometer 8 and the speedometer 9 are of an electric type. For example, the tachometer 8 is a tachometer that passes through an input circuit 11 after the ignition signal from an igniter 10 provided on a crankshaft of an engine (not shown) is waveform-shaped. After being input to the drive circuit 12 and the engine speed is calculated, it is displayed on the tachometer 8.

Further, the speedometer 9 is input to the speedometer drive circuit 15 via the input circuit 14 after the waveform of the shaft rotation signal from the vehicle speed sensor 13 provided on the output shaft of the engine (not shown) is shaped. After the arithmetic processing, it is displayed on the speedometer 9. The ignition signal from the igniter 10 and the vehicle speed sensor 1
The shaft rotation signal from 3 is also input to the CPU 4.

By the way, the pump restart switch 7 is turned on.
When the operation (step 3) is performed and the fuel pump 6 is restarted, the CPU 4 causes the ignition signal number N from the igniter 10 to be N.
When the number of ignition signals Ne is equal to or more than a preset reference value C (Ne ≧
C), the CPU 4 again determines whether or not the fuel in the fuel tank has reached the reserve surface (step 1), and restarts the fuel pump 6 again (step 2). As a result, the driver does not forget that the fuel pump 6 has been restarted, and the vehicle will not run for a long time while the fuel pump 6 is restarted.

The CPU 4 may count the number of shaft rotation signals from the vehicle speed sensor 13 instead of the number of ignition signals Ne from the igniter 10.

FIG. 3 (a) is a flow chart showing a second embodiment of the operating procedure of the fuel quantity warning device for a vehicle. As shown in FIG. 3A, the operation of the second embodiment is the same as that of the first embodiment until the fuel pump 6 is restarted (step 4), but when the fuel pump 6 restarts, the CPU 4 When the number of ignition signals from the igniter 10 (or the number of shaft rotation signals from the vehicle speed sensor 13) Ne is counted and the number of ignition signals Ne becomes equal to or more than a preset first reference value C ₁ (Ne ≧
C ₁ ), CPU 4 is the ignition coil 1 shown in FIG.
A signal is issued to 6 (step 5) to instruct the ignition of the spark plug to be thinned at the thinning rate A (step 6).
As a result, the rotation of the engine becomes unstable, and the driver is prompted to refuel.

If the driver continues to run without refueling, the CPU 4 keeps counting the number of ignition signals Ne from the igniter 10 (or the number of shaft rotation signals from the vehicle speed sensor 13) Ne, and this ignition is performed. The second reference value C ₂ (C ₁ <C in which the number of signals Ne is larger than the preset first reference value C _1
2 ) When it is equal to or more than (Ne ≧
C _2), CPU 4 issues a re signal to an ignition coil 16 (step 7), commands the thinned in more than thinning rate A of the ignition of the spark plug thinning ratio B (A <B) (Step 8). This further impairs the rotation of the engine, makes normal driving difficult, and strongly encourages the driver to refuel.

FIG. 3B is a flow chart showing a third embodiment of the operating procedure of the vehicle fuel remaining amount warning device. As shown in FIG. 3B, the operation of the third embodiment is CP
U4 counts the number of ignition signals from the igniter 10 (or the number of shaft rotation signals from the vehicle speed sensor 13) Ne, and this number of ignition signals Ne becomes equal to or more than a preset first reference value C _1. Until the determination (Ne ≧ C ₁ ) is the same as in the second embodiment, when the determination is made, CP
U4 sends a signal to the rev limiter 17 shown in FIG. 1 (step 5), and controls the ignition coil 16 so that the engine does not operate at a preset first rotation speed (limiter rotation speed) N ₁ or higher (step 9). ). As a result, traveling at a certain speed or higher is restricted, and the driver is urged to refuel.

If the driver continues to run without refueling, the CPU 4 continues to count the number of ignition signals Ne from the igniter 10 (or the number of shaft rotation signals from the vehicle speed sensor 13) Ne, and this ignition is performed. The second reference value C ₂ (C ₁ <C in which the number of signals Ne is larger than the preset first reference value C _1
2 ) When it is equal to or more than (Ne ≧
C ₂ ), the CPU 4 again outputs a signal to the rev limiter 17 (step 10), and the engine outputs a second limiter rotation speed N _{2 that} is less than the preset first limiter rotation speed N _1.
Ignition coil 16 is controlled so as not to operate above (N ₁ > N ₂ ) (step 11). As a result, the regulated traveling speed is further reduced, and the driver is strongly urged to refuel.

According to the above-described embodiment, although the fuel in the fuel tank is reduced, the fuel pump 6 is stopped, and the driver is warned that the remaining amount of fuel is low, the driver does not operate the fuel pump 6. Even if you forget to restart the vehicle, it becomes difficult to drive the vehicle normally, and the driver can be re-warned that the remaining fuel amount is low. If the vehicle is run without refueling despite the re-warning, normal running of the vehicle becomes more difficult, and the driver is strongly urged to refuel. As a result, the fuel will not run out unexpectedly while the vehicle is running.

[0021]

As described above, according to the vehicle fuel remaining amount warning device of the present invention, the fuel sensor having the thermistor at a predetermined position in the fuel tank and the fuel in the fuel tank are supplied to the engine. An electric tachometer for calculating the engine speed by an ignition signal from an igniter provided on the crankshaft of the engine or a shaft rotation signal from a vehicle speed sensor provided on the output shaft of the engine. According to the present invention, at least one of the electric speedometers for calculating the vehicle speed is provided, and when the fuel reaches the predetermined position, the central processing unit stops the fuel pump and restarts the fuel pump stopped by the pump restart switch. In a vehicle that is configured to be capable, the central processing unit is best equipped with the fuel pump. When the ignition signal from the igniter or the shaft rotation signal from the vehicle speed sensor is counted from the time when the signal is stopped, the central processing unit limits the operation of the engine when the number of signals reaches a predetermined value. Due to the configuration, even if the driver forgets to restart the fuel pump, normal running of the vehicle becomes difficult due to the limitation of the engine operation, and the driver is re-warned that the fuel level is low. You can

[Brief description of drawings]

FIG. 1 is a circuit diagram showing an embodiment of a vehicle fuel remaining amount warning device according to the present invention.

FIG. 2 is a flowchart showing a first embodiment of an operating procedure of a vehicle fuel remaining amount warning device.

3 (a) and 3 (b) are flow charts showing a second embodiment and a third embodiment of the operation procedure of the vehicle fuel remaining amount warning device, respectively.

[Explanation of symbols]

1 Thermistor 2 Fuel Sensor 4 CPU (Central Processing Unit) 6 Fuel Pump 7 Pump Restart Switch 8 Tachometer 9 Speedometer 10 Igniter 13 Vehicle Speed Sensor 16 Ignition Coil 17 Rev Limiter A, B Ignition Thinning Ratio C, C ₁ , C ₂ Number of Signals Reference value N ₁ , N ₂ Limiter rotation speed Ne Ignition signal number (shaft rotation signal number)

Claims (1)

[Claims] 1. A fuel sensor having a thermistor at a predetermined position in a fuel tank, and a fuel pump for supplying the fuel in the fuel tank to an engine, and a fuel pump from an igniter provided on a crankshaft of the engine. At least one of an electric tachometer for calculating the engine speed from the ignition signal or an electric speedometer for calculating the vehicle speed from the shaft rotation signal from the vehicle speed sensor provided on the output shaft of the engine is provided, and the fuel is at the predetermined position. When the central processing unit stops the fuel pump when it reaches, in the vehicle configured to restart the fuel pump stopped by the pump restart switch, in the central processing unit, the fuel pump is stopped first. The ignition signal from the igniter or the vehicle speed A remaining fuel amount warning device for a vehicle, wherein the central processing unit limits the operation of the engine when the shaft rotation signal from the sensor is counted and the number of signals reaches a predetermined value.