JP7286252B2 - Remaining amount of fuel calculation device for vehicle - Google Patents

Description

TECHNICAL FIELD The present invention relates to a remaining fuel amount calculating device for a vehicle that calculates the amount of remaining fuel in a fuel tank.

Displaying the remaining amount of fuel in a vehicle such as an automobile is important for the driver to accurately grasp the amount of remaining fuel. Either the sender method that detects the liquid level by the fuel injection device (injector) or the injector method that calculates the remaining fuel amount by subtracting the fuel consumption from the fuel at the time of refueling. Recruitment is taking place.

In the sender method, the remaining amount of fuel A is calculated by the following equation (1) based on a short-time average value (for example, an average value of about 3 seconds) calculated from the input value of the fuel sender. That is, when remaining fuel amount A>short-time average value, the current remaining fuel amount A(n) is calculated by subtracting a predetermined amount Ka from the previous remaining fuel amount A(n-1).
Remaining amount of fuel A(n)=Remaining amount of fuel A(n-1)-Ka (1)
In addition, when remaining fuel amount A<short-time average value, as in the following equation (2), a predetermined amount Ka is added to the previous remaining fuel amount A (n-1) to obtain the current remaining fuel amount A Calculate (n).
Remaining amount of fuel A(n)=Remaining amount of fuel A(n-1)+Ka (2)

However, since the remaining fuel amount A calculated by this sender method uses the fuel sender input value, when the vehicle is approaching an inclined road surface, the actual remaining fuel amount may be affected by changes in the liquid level. There is a problem that it deviates greatly from .

On the other hand, in the case of the injector system, the current remaining amount of fuel B(n) is calculated by subtracting the accumulated fuel consumption value from the previous remaining amount of fuel B(n-1) according to the following equation (3).
Remaining amount of fuel B(n) = Remaining amount of fuel B(n-1) - Integrated fuel consumption value (3)

However, since the remaining amount of fuel B calculated by the above formula (3) in the injector method uses the fuel consumption, it is not affected by the road surface inclination as in the above sender method. Since deviations in the initial value of the remaining amount of fuel and miscalculation of the accumulated amount are accumulated, a deviation from the actual remaining amount of fuel also occurs.

Therefore, a method has been proposed in which the injector method is modified so as to gradually approach the remaining amount of fuel A based on the sender input value.
Remaining amount of fuel B(n)=Remaining amount of fuel B(n-1)-Integrated fuel consumption value+K (4)
where K is a correction value.

In the case of this correction method, the correction value K is set according to the difference between the remaining amount of fuel B and the remaining amount of fuel A calculated from the fuel sender. is subtracted as K<0, and when the remaining fuel amount B is smaller than the remaining fuel amount A, addition is performed as K>0. However, even in this correction method, since the remaining amount of fuel A is used as a parameter, there remains the problem of being affected by the slope of the road surface as in the sender method.

By the way, as described in Patent Document 1, similarly to the injector method, the amount of fuel consumption is calculated from the valve opening time of the injector, and the remaining fuel amount is displayed by subtracting the fuel consumption amount from the fuel amount at the time of refueling. A quantity indicator has been proposed. In addition, in consideration of the fact that the remaining amount becomes inaccurate due to manufacturing errors in the fuel injection device, this patent document 1 discloses that when the liquid level in the fuel tank reaches a preset level, the remaining amount is calculated. It has also been proposed to correct the display.

However, in the device described in Patent Document 1, the correction is performed only at the preset liquid level height, and in other states, there is a possibility that the error from the actual remaining amount becomes large. In addition, as in the injector method and its modification method described above, in the fuel remaining amount calculation using the fuel consumption, two filters with different responsiveness are compared to determine the stable state of the liquid surface, and the stable state is determined. Although it is conceivable to make corrections only at certain times of the day, there is no opportunity to make corrections in conditions such as mountain roads where the liquid level is constantly swaying, and there is a risk that cumulative errors in fuel consumption will accumulate. On the other hand, if feedback correction is performed using the fuel sender input value to avoid this, the frequency of unnecessary correction increases.

JP-A-58-122433

However, as shown in FIG. 6, the fuel tank T thermally expands as the outside air temperature rises, and the full tank capacity increases. Especially when the fuel tank T is made of resin, the increase is greater than that of metal. On the other hand, the float FL of the fuel sender S of the fuel tank T has a structure in which the liquid level cannot rise above the limit level L and cannot be measured unless the liquid level drops to the limit level L. Since there is a non-measurable remaining amount area (shaded area in FIG. 6) where it is not possible to measure, when the fuel tank T thermally expands as indicated by the one-dot chain line in FIG. 6, the non-measurable area increases. As a result, when the fuel tank is filled with fuel, the period during which the meter indicating the remaining amount of fuel indicates that the tank is full becomes abnormally long, giving the driver a sense of discomfort. occurs. Note that P in FIG. 6 represents a fuel pump.

Specifically, for example, when the fuel tank is 36 liters before expansion and the measurable level L of the fuel sender S is 32 liters, the remaining amount unmeasurable region is 4 liters (36 liters - 32 liters). When the capacity of the fuel tank increases to 40 liters due to thermal expansion, the remaining amount unmeasurable area increases to 8 liters (40 liters - 32 liters). When subtraction is started from the nominal full tank, the remaining fuel is above the sender F, which is the upper limit of the liquid level that can be measured due to the structure, but the meter display shows the remaining fuel below the full tank first. Lower to volume display. Specifically, when the meter indicates that the tank is full by lighting 8 segments, the remaining amount is displayed by lighting 7 segments, which is one less segment than when the meter is full. Even if the fuel is refueled at , the amount of fuel remaining in the tank is equal to or greater than that of the sender F, so refueling cannot be detected, and the number of lit segments of the meter does not increase, giving the driver a sense of discomfort.

However, the device described in Patent Document 1 and the conventional method for correcting the remaining amount of fuel cannot solve such problems caused by the swelling of the fuel tank.

SUMMARY OF THE INVENTION It is an object of the present invention to suppress the deviation between the amount of remaining fuel indicated on a meter and the actual remaining amount of fuel in a fuel tank.

In order to achieve the above-described object, the vehicle remaining fuel amount calculating device of the present invention provides a first value calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank. A fuel remaining amount of a vehicle equipped with a control unit that calculates an estimated remaining fuel amount using a remaining amount of fuel and a second remaining amount of fuel calculated based on an input value from a fuel sender that detects the liquid level of a fuel tank. In the amount calculating device, the control unit corrects the first remaining amount of fuel at a predetermined correction rate so that the first remaining amount of fuel approaches the second remaining amount of fuel, When the second remaining amount of fuel exceeds a predetermined remaining amount based on the measurable upper limit of the fuel sender, instead of the predetermined correction factor, the nominal full tank value of the fuel tank and the fuel tank's It is characterized in that constant correction is performed using a correction factor for anti-swelling measures based on the swelling full tank value at the time of swelling.

According to such a configuration, the second remaining fuel amount calculated based on the input value from the fuel sender that detects the liquid level of the fuel tank exceeds the predetermined remaining amount value based on the measurable upper limit of the fuel sender. If so, instead of the predetermined correction factor, a swelling countermeasure correction factor based on the nominal full-tank value of the fuel tank and the swelling full-tank value of the fuel tank when the fuel tank swells is used for constant-rate correction. Even when the fuel tank is filled with fuel, the fuel consumption obtained from the injector valve opening time is subtracted from the fuel amount when the fuel tank is refueled, and the first remaining amount of fuel is calculated. By the time the display starts to decrease from a full tank, it is possible to suppress the discrepancy between the remaining fuel amount displayed on the meter and the actual remaining amount. Thus, it is possible to prevent the problem that the display does not increase even after refueling.

In addition, a first remaining amount of fuel calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank, and the amount of fuel from the fuel sender that detects the liquid level height of the fuel tank. In a vehicle remaining fuel amount calculation device including a control unit that calculates an estimated remaining fuel amount using a second remaining fuel amount calculated based on an input value, the control unit controls the amount of the first remaining fuel amount to the above In order to approach the second remaining amount of fuel, the first remaining amount of fuel is adjusted according to the divergence of the difference between the first remaining amount of fuel and the second remaining amount of fuel and the stability of the liquid surface of the fuel tank. A quantitative correction is performed by subtracting a predetermined value from the remaining amount of fuel, the second amount of remaining fuel does not exceed a predetermined amount of remaining amount based on the measurable upper limit of the fuel sender, and the first amount of remaining fuel is not exceeded. When the remaining fuel amount exceeds a predetermined remaining amount value based on the measurable upper limit of the fuel sender, the predetermined remaining amount of fuel is reduced from the first remaining amount of fuel regardless of the state of divergence and the state of stability of the liquid surface of the fuel tank. Quantitative correction by subtracting the value may be forcibly performed.

According to such a configuration, the second remaining fuel amount calculated based on the input value from the fuel sender that detects the liquid level of the fuel tank exceeds the predetermined remaining amount value based on the measurable upper limit of the fuel sender. and the first remaining fuel amount calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank is a predetermined remaining fuel amount based on the measurable upper limit of the fuel sender. While the condition that the quantity value is exceeded is satisfied, a predetermined value is subtracted from the first remaining fuel amount regardless of the difference between the first and second remaining fuel amounts and the stability of the liquid level in the fuel tank. For example, even if the fuel tank is not full and the automatic stop function of the refueling machine stops refueling before it is full, the forced quantitative correction will It is possible to suppress the deviation between the remaining amount display on the meter and the actual remaining amount, and to more quickly match the remaining amount display on the meter with the actual remaining amount.

According to the present invention, it is possible to suppress the deviation between the remaining fuel amount indicated on the meter and the actual remaining amount of fuel in the fuel tank.

1 is a block diagram of an embodiment of a vehicle remaining fuel amount calculating device according to the present invention; FIG. FIG. 2 is an operation explanatory diagram of FIG. 1; FIG. 2 is an operation explanatory diagram of FIG. 1; FIG. 2 is an operation explanatory diagram of FIG. 1; FIG. 2 is a flowchart for explaining the operation of FIG. 1; FIG. FIG. 10 is an explanatory diagram of swelling of a conventional fuel tank;

An embodiment of a vehicle remaining fuel amount calculating apparatus according to the present invention will be described in detail with reference to FIGS. 1 to 5. FIG.

A vehicle residual fuel amount calculation device 1 according to the present embodiment is configured as shown in FIG. A vehicle speed sensor 3, a float-type fuel sender 4 for detecting the remaining amount of fuel from the height of the liquid surface in the fuel tank T shown in FIG. A fuel consumption amount detection unit 5 for outputting the amount of fuel is connected, and on the output side of the control unit 2 is a fuel remaining amount display unit 6 (hereinafter also referred to as a meter 6) consisting of a liquid crystal display etc. ) are connected. Here, the fuel remaining amount display unit (meter) 6 indicates that the tank is full by lighting, for example, eight segments. ing.

The control unit 2 performs calculations based on the input value from the fuel sender 4 and the first remaining fuel amount B calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank. The estimated remaining amount of fuel is calculated using the second remaining amount of fuel A. Further, the control unit 2 inputs the remaining amount of fuel detected from the liquid level of the fuel sender 4 to the remaining amount of fuel calculation unit 8 via the short-time average value calculation unit 7, and obtains it from the injector valve opening time. The amount of consumed fuel is integrated by the integration unit 9, and the remaining fuel amount calculation unit 8 calculates as follows.

That is, the remaining fuel amount calculation unit 8 of the control unit 2 calculates the difference between the first remaining fuel amount B calculated from the consumed fuel and the second remaining fuel amount A calculated based on the input value from the fuel sender 4. Calculated from the fuel consumption when the amount of divergence (BA) is equal to or greater than a first threshold value C1 (eg, 3 liters) and continues for a first predetermined time period T1 (eg, 5 minutes) or longer. It is determined that there is a deviation in the first remaining amount of fuel B, and a second value calculated based on the short-time (for example, 3 seconds) average value of the input value of the fuel sender 4 and the input value from the fuel sender 4 When the difference from the remaining amount of fuel A is within a second threshold value C2 (for example, 1 liter) and this state continues for a second predetermined time T2 (for example, 10 seconds) or more, the liquid level of the fuel tank is stable, the second remaining fuel amount A calculated based on the input value from the fuel sender 4 is correct, and the fuel sender 4 calculates the first remaining fuel amount B calculated from the consumed fuel. In order to approach the second remaining fuel amount A calculated based on the input value from the Quantitative correction is performed by correcting the first remaining amount of fuel B by a predetermined amount, depending on whether the fuel is stable or unstable.

Further, when the vehicle speed input from the vehicle speed sensor 3 is equal to or higher than a predetermined vehicle speed (for example, 20 km/h), the control unit 2 calculates the fuel consumption calculated from the fuel consumption to the first value calculated from the input value of the fuel sender 4. Correction is performed so as to bring it closer to the remaining combustion amount B. This is because the short-term average value and the remaining amount of fuel match over time when the vehicle speed drops on a long uphill road or curve.

Also, in order to eliminate accumulation of errors, the control unit 2
(1) magnitude relationship between the first remaining fuel amount B obtained from the injector valve opening time and a preset predetermined remaining fuel amount C0;
(2) The amount of deviation between the first remaining amount of fuel B obtained from the injector valve opening time and the second remaining amount of fuel A based on the input of the fuel sender 4 is the first and second thresholds. greater than the values C1, C2 (<C1);
(3) whether the deviation direction between the first remaining amount of fuel B obtained from the injector valve opening time and the average value of the input value of the fuel sender 4 for a short period of time (for example, 3 seconds) is positive or negative;
Constant rate correction is performed by correcting with a correction rate according to the conditions of .

Specifically, as shown in FIG. 2, when the quantitative correction flag provided in the control unit 2 is set to "1", quantitative correction is performed, so the correction rate of the constant rate correction is set to "1". On the other hand, when the fixed amount correction flag is cleared to be "0", the input value (sender value) of the fuel sender 4 is the "predetermined residual amount" in the present invention, which corresponds to the upper limit of the liquid level that can be measured structurally. is greater than or equal to sender F (first remaining fuel amount B≧sender F), the result of the determination is NO, that is, the first remaining combustion amount B is smaller than sender F. In a state where the fuel level in the fuel tank T can be measured by the fuel sender 4, as the condition (1), the first remaining amount of fuel B obtained from the injector valve opening time is set in advance. It is divided into two cases: when it is greater than a predetermined residual fuel amount value C0 (B>C0) and when it is equal to or less than a predetermined residual fuel value C0 (B≤C0). >C0), as the above condition (2), the difference between the first remaining fuel amount B and the second remaining fuel amount A, that is, the divergence amount (BA) is greater than the first threshold value C1. The first remaining fuel amount B is classified into the case where it is large ((B−A)>C1) and the case where it is equal to or less than the first threshold value C1 ((B−A)≦C1). If C0 or less (B≤C0), the difference between the first remaining fuel amount B and the second remaining fuel amount A, that is, the divergence amount is greater than the second threshold value C2 ((B−A) >C2) and the first threshold C1 or less ((B−A)≦C2).

Furthermore, after dividing the condition (2) in this way, the first remaining amount of fuel B and the input value of the fuel sender 4 for a short time (for example, 3 seconds) as the condition (3). If the direction of deviation from the average value of , for example "1.4", "0.6", "1.1", "0.9", "1.6", "0.4", "1.4", "0.6" is set. It is desirable to store such a correction factor as a map in the built-in memory of the controller 2 or the like.

Then, according to the conditions (1) to (3), the control unit 2 reads the corresponding correction factor from the memory and corrects the first remaining amount of fuel B at a constant rate.

However, the volume of the fuel tank T (see FIG. 6) fluctuates due to thermal expansion due to the outside air temperature, and the float of the fuel sender 4 in the fuel tank T cannot float above the limit level of the fuel level. However, since it is a structure that cannot be measured unless the liquid level of the fuel drops to the limit level, there is a region where the remaining amount cannot be measured in the fuel sender 4 as described above. I can't. Further, for example, even if the fuel tank T is not fully filled with fuel and the automatic stop function of the fueling machine stops refueling before the tank is full, the quantitative correction described above cannot sufficiently cope with the situation.

Therefore, in the present embodiment, the deviation between the remaining amount displayed on the meter 6 and the actual remaining amount in such an unmeasurable region is reduced so that the fuel tank T is not filled with fuel, and the refueling machine automatically stops. Even when refueling is stopped before the fuel tank is full due to a function, the following control is performed by the control unit 2 in order to minimize the deviation between the remaining amount displayed on the meter 6 and the actual remaining amount.

That is, the second remaining amount of fuel A, which is equal to the actual remaining amount calculated based on the input value of the fuel sender 4 that detects the liquid level of the fuel tank T, corresponds to the upper limit of the liquid level that can be measured structurally. If the value is F or higher, the fuel sender 4 cannot measure the level of the fuel in the fuel tank T. Therefore, as shown in FIG. If the value (sender value) is greater than or equal to sender F (sender value≧sender F), the determination is YES, and the correction factor at that time is “0.6”. For the first residual fuel amount B calculated by subtracting the consumed fuel obtained from time from the fuel amount at the time of refueling to the fuel tank, the correction factor of the constant correction is, for example, "0.6" for swelling countermeasures. Constant rate correction is performed by a correction factor.

At this time, the swelling countermeasure correction factor is determined as follows.

When all eight segments of the meter (remaining amount of fuel display) 6 are illuminated, the fuel tank is full. Since the sender 4 is in a non-measurable state, all eight segments of the meter 6 remain lit even if the fuel is consumed, and as fuel consumption progresses, the liquid level of the fuel reaches the measurable upper limit of the fuel sender 4. When the fuel tank T is lowered further, the 8th segment of the meter 6 is turned off and 7 segments are turned on. It can be determined that the fuel inside has dropped to the liquid level that can be measured by the fuel sender 4 .

At this time, as shown in FIG. 3, the fuel in the fuel tank T reaches the nominal full level of the fuel tank T when the liquid level at which the lighting state of the meter 6 switches from 8 to 7 is used as a reference. It is set based on the ratio (=x/y) between the height x and the height y of the fuel tank T up to the level when the fuel tank T is swollen and full. With the shape of the tank shown in FIG. 2, the ratio of x/y is approximately 0.6. Therefore, the swelling countermeasure correction factor of the resin fuel tank T is set to "0.6" shown in FIG. It should be noted that this swelling countermeasure correction factor can be calculated almost uniquely according to the material and capacity of the fuel tank T. As shown in FIG.

As shown in FIG. 3, when the swollen fuel tank T is filled with fuel, the fuel level is in a region where the fuel sender 4 cannot measure the fuel level. The first remaining amount of fuel B calculated by subtracting the consumed fuel from the amount of fuel at the time of refueling to the fuel tank approaches the second remaining amount of fuel A, so that the first remaining amount of fuel B is set to a predetermined value. Instead of performing constant rate correction using the correction rate, the control unit 2 performs constant rate correction using the anti-swelling correction rate.

That is, the first remaining fuel amount B calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank decreases from the nominal full tank level as the fuel is consumed, The second remaining amount of fuel A calculated based on the input value from the fuel sender 4 is in a state where it decreases from the swelling full level as the fuel is consumed, and the second remaining amount of fuel A is the fuel sender 4. When the liquid level exceeds the sender F, which corresponds to the upper limit of the liquid level that can be measured structurally, the control unit 2 switches the display of the fuel in the fuel tank T from the 8-segment display of the meter 6 to the 7-segment display. The rate of decrease of the first remaining amount of fuel B is corrected by subtracting the first remaining amount of fuel B by 0.6 times the actual amount of fuel consumption until the surface height decreases. Loosening control is performed.

By doing this, as shown in FIG. 2, the first remaining amount of fuel B, which has been corrected at a constant rate as the fuel level in the fuel tank T decreases, changes from the 8-segment display of the meter 6 to the 7-segment display. , the second remaining amount of fuel A calculated based on the input value from the fuel sender 4 has a similar value, so the remaining amount of fuel reflecting the swelling of the fuel tank T is displayed. can suppress the discrepancy between the remaining amount display on the meter and the actual remaining amount.

On the other hand, even if the fuel tank T is not completely filled with fuel and the automatic stop function of the fueling machine stops the refueling before the tank is full, the lighting state of the meter 6 is changed from 8 to 7. In order to bring the remaining amount displayed on the meter 6 closer to the actual remaining amount, the following forced quantitative correction is performed.

That is, since refueling is stopped before the tank is full due to the automatic stop function of the refueling machine, if constant correction is performed with the above swelling countermeasure correction factor from the full tank state, the remaining amount measurement will be Since the degree of decrease is moderated, the display value of the meter 6 indicated by the two-dot chain line in FIG. Therefore, the second remaining amount of fuel A (one-dot chain line in FIG. 4) does not exceed the sender F, which corresponds to the upper limit that can be measured due to the structure of the fuel sender 4, and is the estimated remaining amount by calculation. 1 (double-dot chain line in FIG. 4) exceeds the sender F, the difference between the first and second remaining fuel amounts B and A and the liquid level of the fuel in the fuel tank T Instead of the normal quantitative correction that is performed depending on the situation, the quantitative correction of the first remaining amount of fuel B is forcibly performed regardless of the deviation situation (divergence amount) and the liquid level situation (fluid level stability). .

More specifically, as shown in FIG. 4, the second remaining amount of fuel A (one-dot chain line in FIG. 4) is below the sender F, and the fuel is discharged until the float of the fuel sender 4 can operate. From time T1 when the surface falls below the lower end of the sender corresponding to the lowered level, the first remaining amount of fuel A is lowered to below the lower end of the sender due to forced quantitative correction, and the first remaining amount of fuel is forcibly corrected quantitatively. Until time T2 when the difference between A and the second remaining amount of fuel A reaches a predetermined amount (for example, 2 liters), the controller 2 continues the forced quantitative correction. At time T3, when the lighting state of the meter 6 is switched from 8 to 7 after switching to normal quantitative correction, the difference between the second remaining fuel amount B and the first remaining fuel amount A is suppressed, and the actual and the remaining amount displayed on the meter 6 substantially match.

Thus, the control procedure for quantitative correction including forced quantitative correction will be described with reference to the flowchart of FIG.

Now, as shown in FIG. 5, when the control unit 2 executes a routine for determining whether or not to perform a quantitative correction every 3.2 seconds, for example, the vehicle speed detected by the vehicle speed sensor 3 reaches a predetermined value. A determination is made as to whether or not the speed (for example, 20 km/h) is higher (step S1), and if the detected vehicle speed is lower than the low speed and the determination result in step S1 is NO, the operation ends, and the detected vehicle speed is higher than the low speed. If the determination result in step S1 is YES, the input value (sender value) of the fuel sender 4 and the sender F whose fuel level in the fuel tank T corresponds to the measurable upper limit due to the structure of the fuel sender 4. In order to determine whether the fuel sender 4 is in a measurable state or a measurable state by comparison, it is determined whether or not the sender value is smaller than the sender F (step S2).

If the determination result in step S2 is NO, the fuel level in the fuel tank T is too high and the fuel sender 4 cannot measure, so the operation is terminated and the determination result in step S2 is YES. If so, it is determined that the fuel level is lowered and the fuel sender 4 is in a measurable state, and it is determined whether or not the second remaining fuel amount A, which is the estimated remaining amount, is greater than or equal to the sender F. is performed (step S3).

If the determination result in step S3 is YES, the process proceeds to step S6, which will be described later, in order to perform the forced quantitative correction described above. 2, that is, the amount of deviation (B−A) and the first threshold value C1 (step S4). A first threshold value C1 (for example, 3 liters) or more is a state in which the divergence amount (BA), which is the difference between the first remaining fuel amount B and the second remaining fuel amount A, is equal to or greater than the first threshold value C1. It is determined whether or not the first remaining fuel amount B calculated from the consumed fuel and the second remaining fuel amount A measured by the fuel sender 4 do not come close to each other for a predetermined time T1 (for example, 5 minutes) or longer. be judged.

If the deviation determination result in step S4 is NO, it is determined that there is no deviation, and the operation ends. It is determined that there is a deviation without approaching the remaining amount of fuel A, and determination of liquid level stability is made in the next step S5. In this determination of the liquid level stability, as described above, the second remaining fuel amount A calculated based on the short-time (for example, 3 seconds) average value of the input value of the fuel sender 4 and the input value from the fuel sender 4 is within a second threshold value C2 (eg, 1 liter) and the state continues for a second predetermined time T2 (eg, 10 seconds) or longer.

If the determination result in step S5 is NO, the liquid level of the fuel in the fuel tank T is unstable and the operation is terminated. If the determination result in step S5 is YES, the liquid level is stable. A quantitative correction flag provided in the control unit 2 is set to "1" (step S6). is done and then the operation ends. At this time, when the step S3 is passed with YES, the quantitative correction is forcibly executed with a predetermined correction amount regardless of the divergence state and the liquid level state based on the determinations in steps S4 and S5, and the step S3 is NO. , quantitative correction is performed with a predetermined correction amount according to the state of divergence and the state of the liquid surface based on the determinations in steps S4 and S5.

In this way, by performing the forced quantitative correction regardless of the divergence, the liquid level stability, or the instability, when the lighting state of the meter 6 switches from 8 to 7, the fuel sender 4 is in the measurable region. It is possible to substantially match the actual remaining amount with the remaining amount displayed on the meter 6 by suppressing the deviation between the remaining amount displayed on the meter 6 and the actual remaining amount.

Therefore, according to the above-described embodiment, the second remaining amount of fuel A calculated based on the input value from the fuel sender 4 that detects the liquid level of the fuel tank T is based on the measurable upper limit of the fuel sender 4. If the remaining amount exceeds the predetermined remaining amount (sender F), instead of the predetermined correction factor, the nominal full tank value of the fuel tank T and the swollen full tank value of the fuel tank (previously The value obtained by adding the expected amount of swelling) is used for the correction factor for anti-swelling measures (=x/y). However, the second remaining fuel amount A is made closer to the first remaining fuel amount B calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount when refueling the fuel tank T. It is possible to suppress the deviation between the remaining amount displayed on the meter 6 and the actual remaining amount, and prevent the driver from feeling uncomfortable due to the meter continuously displaying the full tank as in the conventional art. can be prevented.

Further, while the condition that the second remaining fuel amount A does not exceed the sender F and the first remaining fuel amount B exceeds the sender F is satisfied, the first and second remaining fuel amounts are Regardless of the divergence between the amounts B and A and the stability of the liquid level in the fuel tank T, the quantitative correction is forcibly performed by subtracting a predetermined value from the first remaining amount of fuel B. Even if refueling is stopped before the tank is full due to the automatic stop function of the refueling machine, the discrepancy between the remaining amount displayed on the meter 6 and the actual remaining amount is suppressed by forced quantitative correction. This allows the display of the remaining amount of fuel on the meter 6 to match the actual remaining amount more quickly.

The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the scope of the present invention.

For example, the correction rate in the constant rate correction exemplified in the above embodiment is not limited to the values shown in FIG. In particular, the swelling countermeasure correction factor (=x/y) is not limited to "0.6", and may be appropriately set according to the material and capacity of the fuel tank.

In the above-described embodiment, the fixed rate correction using the anti-swelling correction factor when the fuel tank T swells and the forced quantitative correction under predetermined conditions are performed. Only correction, or only forced quantitative correction under predetermined conditions, may be performed.

INDUSTRIAL APPLICABILITY The present invention can be widely applied as a vehicle remaining fuel amount calculating device for calculating the amount of fuel remaining in a fuel tank.

DESCRIPTION OF SYMBOLS 1... Remaining amount of fuel calculating device 2... Control part 4... Fuel sender T... Fuel tank

Claims (2)

The first remaining amount of fuel calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank, and the input value from the fuel sender that detects the liquid level height of the fuel tank In a vehicle remaining fuel amount calculation device including a control unit that calculates an estimated remaining fuel amount using a second remaining fuel amount calculated based on
The control unit
constant-rate correction of the first remaining amount of fuel at a predetermined correction rate so that the first remaining amount of fuel approaches the second remaining amount of fuel;
When the second remaining amount of fuel exceeds a predetermined remaining amount based on the measurable upper limit of the fuel sender, instead of the predetermined correction factor, the nominal full tank value of the fuel tank and the fuel tank's 1. A remaining amount of fuel calculation device for a vehicle, characterized in that constant rate correction is performed using a correction factor for anti-swelling based on a swelling full tank value at the time of swelling. The first remaining amount of fuel calculated by subtracting the fuel consumption obtained from the injector valve opening time from the fuel amount at the time of refueling to the fuel tank, and the input value from the fuel sender that detects the liquid level height of the fuel tank In a vehicle remaining fuel amount calculation device including a control unit that calculates an estimated remaining fuel amount using a second remaining fuel amount calculated based on
The control unit
Deviation of the difference between the first remaining amount of fuel and the second remaining amount of fuel, and stabilization of the liquid level of the fuel tank so that the first remaining amount of fuel approaches the second remaining amount of fuel. According to the situation, quantitative correction is performed by subtracting a predetermined value from the first remaining fuel amount,
The second remaining amount of fuel does not exceed a predetermined remaining amount of fuel based on the measurable upper limit of the fuel sender, and the first remaining amount of fuel does not exceed the predetermined remaining amount of fuel based on the measurable upper limit of the fuel sender. A quantitative correction is forcibly performed by subtracting the predetermined value from the first remaining amount of fuel when the amount exceeds the amount, irrespective of the state of divergence and the state of stability of the liquid surface of the fuel tank. Vehicle fuel remaining amount calculation device.

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