JPH02157468A - Device for feeding fuel of vehicle - Google Patents

Abstract

PURPOSE:To make a driver artificially realize the condition of fuel shortage by reducing a fuel feeding quantity bit by bit based on a signal which is generated at the time of detecting that the remaining quantity of fuel in a fuel tank becomes small. CONSTITUTION:In a processing device 7, when the liquid surface in a tank 1 is high, a thermistor input is at a low level of (a) and a current (b) flows in a solenoid 3a. When the liquid surface is lowered, the thermistor is exposed in the air and its temperature rises to increase the quantity of a current, generating a signal A. The processing device 7 controls the voltage of a third terminal by this signal and turns on/off a transistor 8 to control a solenoid current, thereby gradually reducing a conduction time at a defined period T to gradually reduce the exciting time of the solenoid 3a in accordance with the lapse of time (t). Thereby, the fuel quantity passing through a solenoid valve 3 is reduced in proportion to the exciting time. Hence, the output of an engine is gradually lowered enabling a drive to sense this.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a fuel supply device for an automobile, a work vehicle, etc., which is equipped with a fuel exhaustion warning device.

(Prior art) When the remaining amount of fuel in a fuel tank becomes low, the remaining amount is electrically detected and a warning is generated by flashing a reserve warning lamp. A device in which the fuel passage is opened is known from Japanese Utility Model Application No. 49-148310.

There are also known fuel stop devices that automatically stop the fuel pump or stop the function of the negative pressure cock in the fuel supply system to cut off the fuel supply after warning that the remaining amount is low. .

(Problem to be Solved by the Invention) In each of the above-mentioned conventional technologies, even if a warning is issued from the reserve warning lamp due to a decrease in the remaining amount, the fuel supply amount does not change much for a while and remains almost normal. Because it can run,
The driver may ignore the warning and not take immediate steps to refuel. In such a case, the vehicle will run out of fuel while driving. Further, among the above-mentioned conventional technologies, those equipped with an automatically operating fuel stop device have a problem in that the engine stops unexpectedly.

In addition, in a fuel supply system that has two types of discharge ports, high and low, in the fuel tank and a fuel cock that switches between the discharge ports, even if the fuel liquid level becomes lower than the higher discharge port, it will remain high for a while due to the waves in the tank. Fuel is supplied from one outlet, and the engine gradually runs out of gas. Therefore, the driver can recognize that the gas is running out before the engine completely stops.

Therefore, an object of the present invention is to provide means for warning the driver that the amount of fuel remaining is low with a feeling equivalent to the feeling of running out of gas in the above-mentioned discharge port switching type fuel supply device.

(Means for Solving the Problems) The means for solving the above problems of the present invention include a fuel supply system that supplies fuel from a fuel tank to an engine, and a system that detects when the remaining amount of fuel in the fuel tank becomes small. The fuel supply system for a vehicle is characterized in that the fuel supply system includes a control means for decreasing the amount of fuel supplied little by little based on the signal.

(Function) Since the above-mentioned means is provided, when the remaining amount of fuel decreases, the amount of fuel supplied to the engine is gradually reduced, and the output of the engine gradually decreases and the speed decreases. This allows the driver to feel the decrease in the remaining amount.

(Example) Examples of the present invention will be described below with reference to the drawings. In Fig. 1, 1 is a fuel tank installed in an automobile, 2 is a fuel supply pipe, and 3 is a solenoid valve equipped with a solenoid 3a, which is normally open, but the flow rate can be adjusted by the solenoid 3a, and the fuel It is supplied to the engine's carburetor via the solenoid valve 3.

A thermistor 4 as a liquid level detection means is installed at a low position in the fuel tank 1, and generates a signal based on temperature changes when the liquid level drops.

5 is a control unit that controls the solenoid valve 3 based on the signal.
This gradually reduces the fuel flow rate and reduces engine output. Reference numeral 6 denotes a return switch, which is installed at an easily accessible location 1 on the inside of the fairing or around the steering wheel, and when the driver closes the switch, the action of the control unit 5 is stopped and the solenoid valve 3 is opened. The state returns to the state where the normal amount of fuel is supplied. This state is the same as when the preliminary fuel supply port in the conventional device is opened.

Figure 2 shows the configuration of the control unit 5.
A processing device 7, a transistor 8 that operates the solenoid 3a, and a transistor l that operates the reserve warning lamp 9.
O, and a voltage divider 11 for detecting disconnection of the solenoid 3a.

In the processing device 7, when the liquid level in the tank 1 is high, the thermistor input is at a low level a, as shown in FIG. When the surface lowers, the thermistor is exposed to the air and increases in temperature, increasing the amount of current and generating signal A.

The processing device 7 controls the voltage of the third terminal by this signal A, controls the solenoid current by turning on and off the transistor 8, and sequentially decreases the conduction time 1...T,... with a constant period T. , duty control is performed to sequentially decrease the excitation time of the solenoid 3a as time t elapses. As a result, the amount of fuel passing through the solenoid valve 3 decreases in proportion to the excitation time. Therefore, a so-called gas starvation condition gradually appears in the engine, and the output decreases, which can be detected by the driver.

A voltage is generated at the fourth terminal of the processing device 7 for 3 seconds when the engine switch is closed, and this voltage lights up a warning lamp for 3 seconds to detect whether or not the engine is out of power. Depending on the fifth terminal, the voltage of the voltage divider 11 is introduced to detect whether or not the solenoid 3a is disconnected.

FIG. 4 is a flowchart of the processing device 7.

First, by turning on the main key of the engine, in step ■, the reserve warning lamp 9 is lit for 3 seconds to detect the presence or absence of a drain, and in the next step ■, it is detected whether the liquid level is low, and if the liquid level is normal. Step (2) turns on the circuit of the solenoid 3a, step (2) detects whether or not the solenoid 3a is disconnected, and if it is broken, the reserve warning lamp 9 is blinked in step (2).

Further, in step (2), when a drop in the liquid level is detected in step (2), the reserve warning lamp 9 is blinked, but if the solenoid is disconnected and the lamp is blinking, it continues to blink. Then, when a drop in the liquid level is detected and the return switch is turned off (in other words, in the normal position), the output is duty-controlled by controlling the current flowing through the solenoid 3a as shown in FIG. 3 in (). If the return switch 6 is turned on in step ■, turn on the solenoid 3a in step ■, and connect it to step ■.

As mentioned above, the combustion supply amount is controlled by a solenoid valve that is directly driven by the solenoid 3a, but it is not limited to such a solenoid valve, but a valve that is adjusted by a servo motor or a negative pressure cock whose negative pressure can be adjusted can also be used. Can be used.

These means may be either a natural fall type or a pump type for feeding the fuel O (yarn feeding), and the operation mode of the fuel control means is not limited to adjusting the on/off time, but also gradually narrowing down the flow path area. If a fuel pump is used, the operating speed of the pump may be gradually slowed down.

(Effects of the Invention) As described above, the present invention reduces the amount of fuel supplied to the engine when the remaining amount of fuel decreases, lowers the engine output and vehicle speed, and artificially makes the driver feel a state of fuel shortage. Therefore, there is no risk that the condition will be ignored or disregarded.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of the present invention, FIG. 2 is a system diagram of the control unit, FIG. 3 is a diagram for explaining the operation, and FIG. 4 is a flow chart. 1... Fuel tank 4... Detection means (thermistor) 5... Control means (control unit) Patent applicant Honda Motor Co., Ltd. Figure 1 Figure 3

Claims (1)

[Claims] A fuel supply system for a vehicle, comprising a fuel supply system that supplies fuel from a fuel tank to an engine, and a detection means that detects that a small amount of fuel remains in the fuel tank and generates a signal, A fuel supply device for a vehicle, characterized in that the fuel supply system is equipped with a control means for decreasing the amount of fuel supplied little by little based on the signal.