JPS63200017A - On-vehicle detecting device for residual fuel quantity - Google Patents

Abstract

PURPOSE:To enable the invariably stable and accurate detection of the residual quantity of fuel by a method wherein the residual quantity of fuel detected on the basis of the injection quantity of fuel injected from a fuel injection valve in running is corrected by the residual quantity of fuel in a fuel tank at the time of stoppage. CONSTITUTION:The residual quantity L of fuel stored in a tank is detected on the basis of a liquid level by the operation of a tank fuel residual quantity detecting means 4, irrespective of whether a vehicle runs or stops. With the residual quantity L taken as an initial value and on the basis of the injection quantity of fuel supplied to an engine by injection, the residual quantity of fuel is calculated by a fuel residual quantity calculating means 9 receiving an output signal of a running detecting means 8 while the vehicle runs. Unlike the detection of the liquid level by the means 4, this method enables the execution of stable detection not affected by variations due to the motion of a car body in running. When the running is stopped, the residual quantity of fuel calculated by the means 9 is corrected with the exact residual quantity L at the time of stoppage detected by the means 4, by an operation of a correcting means 10 on the basis of an output signal of the means 8. Accordingly, accurate detection can be attained at every stoppage even when an error occurs in the means 9.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an improvement in a remaining fuel amount detection device for detecting the remaining amount of fuel loaded in a vehicle equipped with a fuel injection engine.

(Prior Art) Conventionally, as a fuel remaining amount detection device for a vehicle, a fuel tank for storing fuel has a float that moves up and down in accordance with the liquid level of the fuel in the tank, and the amount of movement of the float is Generally, a float type is well known in which the remaining amount of fuel is detected in accordance with the liquid level of the fuel in the tank detected by a gauge having a gauge whose electrical resistance value varies accordingly.

However, with this float type, when the vehicle is moving with a tilting body, especially when accelerating or decelerating, the fuel level in the fuel tank moves up and down as the body tilts, so the output value of the gauge changes. This has the disadvantage that the remaining fuel amount may fluctuate, resulting in unstable display of the remaining fuel amount. For this reason, for example, when using a so-called touring computer that instantaneously calculates the remaining fuel level and the drivable distance based on it while the vehicle is running, and displays this data every moment, the displayed data may be incorrect. There is a risk that it will be accurate.

Therefore, conventionally, as shown in Japanese Utility Model Application Publication No. 59-31024, etc., in a vehicle equipped with a fuel injection type engine that injects fuel into the intake system through a fuel injection valve, there is a problem in the fuel tank when the vehicle is stopped. The remaining amount of fuel is set as an initial value, and while the vehicle is running, the remaining amount of fuel is detected based on the amount of fuel injected from the fuel injection valve within a unit time, and the detected value is displayed. Accordingly, a system has been proposed in which the display of the fuel cost m does not change even if the vehicle body tilts while the vehicle is running.

(Problem to be Solved by the Invention) However, in this proposal, although the fuel injection from the fuel injection valve is relatively accurate and the error is small, the number of times it is injected is large, so the error is large. This results in a large error (approximately 10%) that cannot be ignored in the remaining amount of fuel.

The present invention has been made in view of the above, and an object of the present invention is to solve the basic structure of detecting the remaining amount of fuel based on the amount of fuel injected into the engine by the fuel injection valve. Another object of the present invention is to make it possible to always accurately detect the remaining amount of fuel by effectively incorporating a method of detecting the remaining amount of fuel based on the fuel level in the fuel tank.

(Means for solving the problem) In order to achieve this object, the solving means of the present invention detects the remaining amount of fuel based on the fuel i1 injection volume injected from the fuel injection valve while the vehicle is running. When the vehicle is in a stationary state where there is no fluctuation in the level of fuel in the fuel tank, the detected fuel cost W is corrected by J: the remaining amount of fuel in the fuel tank.

Specifically, in the present invention, as shown in FIG. 1, a traveling detection means 8 for detecting the traveling state of the vehicle is used as a fuel cost detection device for detecting the fuel cost of a vehicle equipped with a fuel injection engine. and tank fuel remaining amount detection means 4 for detecting the remaining ff1L of fuel stored in the fuel tank of the vehicle based on the liquid level.

Then, the output signals of both the detection means 8 and 4 are input, and the fuel injection 9A is injected and supplied to the engine with the fuel amount ff1Lo detected by the remaining tank fuel amount detection means 4 as an initial value while the vehicle is running. A remaining fuel amount calculating means 9 is provided for calculating the remaining fuel amount based on the fuel amount.

Further, the output signals of both the detection means 8 and 4 are inputted, and when the vehicle stops running, the remaining fuel amount calculated by the fuel remaining amount calculation means 9 is calculated based on the output signal of the detection means 4. A correction means 10 for correction is provided.

(Function) With the above configuration, in the present invention, the remaining tf of fuel stored in the fuel tank of the vehicle is detected by the operation of the tank fuel remaining amount detection means 4 regardless of whether the vehicle is running or not running.
flLo is detected based on its liquid level. When the vehicle is running, the fuel remaining amount calculation means 9 that receives the output signal from the running detection means 8 calculates the remaining fuel amount using the fuel amount ff1Lo detected by the tank fuel amount detection means 4 as an initial value and the engine. It is calculated based on the fuel 11 injection ■ that is injected. At this time, since the fuel cost mff1 is calculated based on the fuel injection amount supplied to the engine, the fuel cost ff1Lo is detected based on the liquid level of fuel 1 in the fuel tank. The remaining amount of fuel does not fluctuate due to tilting of the vehicle body while driving, and the amount of remaining fuel can be detected stably.

On the other hand, when the vehicle stops running, the correcting means 10 operates in response to the output signal of the running detecting means 8, and the operation of the correcting means 10 causes the remaining fuel amount calculated by the remaining fuel amount calculating means 9 to be adjusted. However, the tank is burnt; the fuel 9 in the fuel tank detected by the remaining amount detection means 4! UILo
Corrected based on

When the vehicle is stopped, there is no tilting of the vehicle body and the liquid level of the fuel in the fuel tank does not fluctuate.
is accurate. Therefore, even if there is an error in the remaining fuel amount calculated by the fuel remaining amount calculation means 9, each time the vehicle stops, the remaining fuel amount is calculated based on the accurate fuel amount f in the tank.
This means that accurate detection can be performed based on f1Lo.

(Example) Embodiments of the present invention will be described below based on the drawings.

In FIG. 2, 1 is the body of a car as a vehicle, 2 is a fuel injection engine mounted on the front of the car body 1,
Reference numeral 3 denotes a fuel tank that is installed at the rear of the vehicle body 1 and stores fuel to be supplied to the engine 1, and this fuel tank 3 has a device that detects the fuel amount ff1Lo in the fuel tank 3 based on its liquid level. A liquid level sensor 4 is attached as means for detecting the remaining amount of fuel in the fuel tank, and this liquid level sensor 4 has a float (not shown) that moves up and down in accordance with the liquid level of the fuel in the fuel tank 3. The electrical resistance value as an output signal varies depending on the amount of movement of the float. The output signal (electrical resistance signal @) of the liquid level sensor 4 is CP
It is input to the control unit 5 which has a built-in U. In addition to signals from the liquid level sensor 4, this control unit 5 also receives a vehicle speed signal from a vehicle speed sensor v6 that detects the traveling speed of the vehicle, and an ON/OFF signal from an ignition key switch (not shown). , fuel injection ff supplied to the engine 2 within a unit time
A fuel injection signal corresponding to 1k is input. The output signal of this control unit 5 is transmitted to the vehicle interior 1.
The fuel is outputted to a fuel indicator 7 attached to the instrument panel 1b on the front side, and this fuel indicator 7 displays the remaining amount of fuel.

Here, the signal processing procedure for detecting and displaying the remaining fuel amount in the control unit 5 will be explained based on FIG. 3.

First, in the first step S1, the flag F is cleared to F=0. This flag F identifies that the residual fuel F31 is detected based on the fuel injection amount k for the engine 2, and is set to F=1 in the detection state based on the fuel injection amount k. Ru. After that, in step S2, it is determined whether the ignition key switch is in the ON state, and if it is determined that the ignition key switch is in the ON state, the ignition key switch is
After proceeding to Step 3 and inputting the value of the fuel cost mLo from the liquid level sensor 4, it is determined in Step S4 whether or not the automobile is running based on the output signal of the vehicle speed sensor 6. Here, if the determination is YES that the vehicle is running, the flow proceeds to steps 85 to S9, and the remaining amount of fuel is calculated based on the fuel injection amount k.

That is, in step S5, the fuel cost m L is set to the fuel cost iLo detected by the liquid level sensor 4 as an initial value.
+ is set, and in the next step S6, the fuel injection amount k is subtracted from the fuel r1 remaining amount L1, and the fuel amount RL1 is updated to 1 with a new fuel remaining amount. After setting the flag F@F="1 in the next step S8, the process proceeds to step S9,
The remaining fuel amount L1 detected in step S7 is displayed on the fuel indicator 7, and then the process returns to step S4.

On the other hand, if it is determined in step S4 that the vehicle is not running, the process proceeds to step 31F1-315 and the remaining fuel amount is corrected. That is, in step SIO, it is determined whether the flag FSF=1 or not, and when this determination is No (F=0), the process directly returns to step S4. If it is determined in step 31G that F=1 (YES), the value (remaining fuel amount) Lo of the liquid level sensor 4 is inputted in step So, and the value f is input in step SI2.
The fluctuation speed dLo/dt of cILo is determined, and step S
At I3, it is determined whether the fluctuating speed d Lo /d↑ is smaller than the reference value ε. In other words, while the car is running, as the car body 1 tilts, the fuel tank 3 fixedly supported by the car body 1 also moves, so the rate of fluctuation of the fuel level inside the tank 3 is large. Once the vehicle stops running, the fluctuations in the fuel level gradually subside and eventually reach zero.

Then, when the liquid level fluctuation rate d Lo /d t is lower than the reference value ε, the liquid level is considered to be in a stable state, and the fuel cost ff1Lo at that time is detected. The determination in step 313 is ε>(dLo/dt).
Repeat steps So to SI3 until ES is reached.
When the determination is YES, the process proceeds to step 314 where the fuel cost ff1Lo is calculated as the average faLo of the fuel cost ILo and the fuel cost m L + calculated above.
Correct it to 10L+)/2. Next, in step S's, the fuel cost mho corrected in step 314 is displayed on the fuel indicator 7, as in step S9, and then the process returns to step S4.

Therefore, in this embodiment, the running detecting means 8 is configured to detect the running state of the automobile by step S4 in the above-described flow.

Similarly, in steps 85 to Sy and 39, each output signal of the liquid level sensor 4 and the running detection means 8 is inputted, and the fuel cost ff1Lo detected by the liquid level sensor 4 while the car is running is set as an initial value. A remaining fuel amount calculation means 9 is configured to calculate the remaining fuel amount L1 based on the fuel injection 1k supplied to the engine 2, and display the fuel cost mL1 on the fuel indicator 7.

Furthermore, in steps 3o to S's, each output signal of the liquid level sensor 4 and the running detecting means 8 is inputted, and when the vehicle stops running, the remaining fuel amount L1 calculated by the remaining fuel amount calculating means 9 is inputted. A correction means 10 is configured to correct the difference based on the output signal of the liquid level sensor 4.

Next, the operation of the above embodiment will be explained with reference to FIG. 4.

First, when the ignition key switch is turned ON, the fuel amount iLo in the fuel tank 3 is detected by the liquid level sensor 4 in the ON state.

Thereafter, when the engine 2 is started by fuel injection and the automobile shifts to a running state, the running state is detected by the running detecting means 8, and the remaining fuel amount calculating means receives the output signal of the running detecting means 8. 9, the fuel amount 114 L 1 at the time when the fuel injection amount k per unit time that is injected and supplied to the engine 1 is gradually reduced from the fuel amount ♀Lo detected by the liquid level sensor 4. =Lo
−, and this calculated fuel cost 1jt L
1 is displayed by the fuel indicator 7 on the instrument panel 1b.

At this time, since the fuel ¥31 remaining ffi L1 is calculated based on the fuel injection amount k injected to the engine 2, the fuel cost ff1Lo detected by the liquid level sensor 4 is directly displayed by the fuel indicator 7. As in the above case, the detected and displayed fuel cost ε does not change due to fluctuations in the fuel level in the fuel tank 3 due to the tilting of the vehicle body 1, that is, the fuel tank 3 when the car is running, and therefore the remaining fuel amount does not change. can be detected and displayed stably.

When the vehicle stops running, the stopped state is detected by the running detecting means 8, and the correcting means 10 receives the output signal of the running detecting means 8, and the fuel cost m is calculated by the fuel cost m calculating means 9. The remaining fuel amount L1 is corrected by the fuel amount ff1Lo in the fuel tank 3 detected by the liquid level sensor 4 when the automobile is stopped, and the value Lo is obtained.

The average value of Ll (Lo+L+)/2 is the new fuel cost ff
This new fuel cost ff1L is calculated as 1Lo.

-(Lo+L+)/2 is displayed by the fuel indicator 7.

At this time, when the vehicle is stopped, there is no tilting of the vehicle body 1 and the fluctuation in the fuel level in the fuel tank 3 is small, so the fuel cost ωLo detected by the level sensor 4 is an accurate value. It will not be shown.

For this reason, the remaining fuel amount L1 based on the fuel injection 11
When calculating, even if an error occurs in the calculated remaining fuel amount L1, the error is equal to the accurate fuel amount iL detected by the liquid level hinter 4.

This correction allows the remaining fuel amount to be accurately detected and displayed.

Furthermore, even when the vehicle is stopped, the liquid level sensor 4
The remaining fuel amount ILo detected by is not immediately adopted as is, and the fluctuation speed dLo/dt of the remaining fuel amount LO is set to the reference value ε.
, and only the value when the fluctuation of the fuel level in the fuel tank 3 is small is adopted as the remaining fuel amount Lo.
The fuel price ff1L○ detected by the liquid level sensor 4 becomes extremely accurate, and therefore the remaining amount of fuel can be detected even more accurately.

In the above embodiment, when correcting the remaining fuel amount when the vehicle is stopped, the fuel injection ff1 that is injected and supplied to the engine 1 is
Remaining fuel ff1L calculated based on k.

and the remaining fuel amount L detected by the liquid level sensor 4 when stopped.
1 and the average value (Lo+L+)/2 is set as the new remaining fuel amount, but the remaining fuel amount ILo detected by the liquid level sensor 4 is used as it is to inject fuel into the engine 1 (9A).
It may be replaced with the remaining fuel m l-1 based on ffi, and the same effects as in the above embodiment can be achieved.

(Effects of the Invention) As explained above, according to the present invention, when the vehicle is running, the remaining amount of fuel is detected based on the fuel injection source injected to the engine, and when the vehicle stops, the amount of fuel in the fuel tank is detected. By correcting the remaining fuel amount calculated based on the fuel injection amount based on the remaining fuel amount detected by the fuel level, the fuel amount is calculated based on the fuel injection amount while the vehicle is running. It is possible to stably detect the remaining amount of fuel regardless of the tilting of the vehicle body, and the error at that time can be corrected when the vehicle is stopped, making it possible to always stably and accurately detect the remaining fuel amount of the vehicle. It is something.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of the present invention. 2 to 4 show an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the overall configuration, and FIG. 3 is a flowchart showing the processing procedure of Shintan processed by the control unit.
FIG. 4 is a timing chart for detecting the amount of fuel remaining at $31. 2... Engine, 3... Fuel tank, 4... Liquid level sensor, 5... Control unit, 8... Running detection means, 9... Fuel remaining amount calculation means, 10... Correction means.

Claims (1)

[Claims] (1) A fuel remaining amount detection device for detecting the remaining fuel amount of a vehicle equipped with a fuel injection engine, which includes a driving detection means for detecting the driving state of the vehicle, and a driving detection means for detecting the driving state of the vehicle, and a driving detection device for detecting the remaining fuel amount of a vehicle equipped with a fuel injection engine. A tank fuel remaining amount detection means detects the remaining amount based on the liquid level, and the output signals of both of the above detection means are input, and while the vehicle is running, the remaining fuel amount detected by the tank fuel remaining amount detection means is initialized. A fuel remaining amount calculating means for calculating the remaining fuel amount based on the amount of fuel injected to the engine as a value, and output signals from both of the above detection means are input, and when the vehicle stops running, the remaining fuel amount calculating means calculates the remaining fuel amount. A fuel remaining amount detection device for a vehicle, comprising: a correction means for correcting the calculated remaining fuel amount based on an output signal of the tank fuel remaining amount detection means.