JPH0262804B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drivable distance display device for calculating and displaying the drivable distance of a vehicle such as an automobile with its remaining fuel amount.

Conventionally, this type of product was published in Japanese Patent Application Laid-open No.
There is No. 120250 "Remaining Odometer", which calculates the instantaneous fuel consumption from the relationship with the distance traveled during that time every time a small amount of fuel is consumed, and calculates and displays the possible driving distance from this instantaneous fuel consumption and the remaining fuel at that time. There is something I did.

However, this method calculates the possible driving distance based on the instantaneous fuel consumption at the time of driving, so when driving idling, the instantaneous fuel consumption is 0.
There is a problem in that the drivable distance is incorrectly displayed as 0 even though there is fuel remaining.

The present invention has been developed in view of the above-mentioned problems, and its purpose is to prevent false indications such as 0 driving distance even though there is fuel remaining when idling continues. The object of the present invention is to provide a drivable distance display device.

The present invention will be described below with reference to embodiments shown in the drawings. Figure 1 is a book diagram showing the overall configuration of the system, in which the drivable distance is calculated and displayed using an on-vehicle microcomputer that executes digital calculation processing by software according to a predetermined distance calculation control program. There is.

In this Figure 1, 1 is the instantaneous fuel consumption of the car,
An instantaneous fuel consumption meter that detects kilometers (Km)/liters (), fuel consumption speed/sec and driving speed.
Detect Km/sec and calculate instantaneous fuel consumption (Km/) by dividing the traveling speed by the fuel consumption rate,
The instantaneous fuel consumption signal is generated as a digital signal, and is constructed in the same manner as that shown in, for example, ``Instantaneous Fuel Consumption Meter'' in Japanese Patent Application Laid-Open No. 51-80257. Then, the distance traveled by the vehicle (Km) is determined by this instantaneous fuel consumption meter.
and fuel consumption detection means for detecting momentary fuel consumption based on the fuel consumption amount (). 2 is a fuel meter which is a fuel detection means that detects the remaining fuel amount F in the fuel tank of the automobile and generates a digital remaining fuel amount signal; 3 is a repeating timer that generates an interrupt pulse at a cycle of 1 second. This interrupt pulse is used to command sampling of the instantaneous fuel consumption. 4 is a single-chip microcomputer that executes software digital calculation processing according to a predetermined distance calculation control program;
A crystal resonator 5 of several megahertz (MHz) is connected, and it is activated by receiving a stabilized voltage of 5 volts (V) from a stabilized power supply circuit (not shown) that receives the power supply voltage of an on-board battery. , the fuel consumption signal from the instantaneous fuel consumption meter 1 is sampled by the interrupt pulse from the repeat timer 3, the fuel consumption data is integrated, and when the number of samplings reaches 60, the integrated value a and the number of samplings are obtained. Calculate the average fuel consumption A by dividing A=a/60, and calculate the travelable distance D based on this average fuel consumption A and the remaining fuel amount F from the fuel remaining amount signal from the fuel gauge 2 as D=F・A It calculates the distance by multiplying it and commands the display of the distance, and also commands an alarm when the drivable distance D becomes less than 20km. This microcomputer 4 has a read-only memory (Read Only Memory) that stores the distance calculation control program that defines various calculation processing procedures for determining the travelable distance.
ROM) and a central processing unit (Central Processing Unit) that sequentially reads the distance calculation control program in this ROM and executes the corresponding calculation processing.
CPU) and temporarily stores various data related to the arithmetic processing of this CPU.
Memory that can be read by the CPU (Random
an access memory (RAM), a clock generation section that generates reference clock pulses for the various calculations described above using a crystal oscillator 5, and an input/output (I/0) circuit section that adjusts the input and output of various signals. The main part is made of a single-chip large-scale integrated circuit (LSI). 6 has a drivable distance D
Microcomputer 4 when the distance is less than 20km
This is an alarm device as an alarm means that issues an alarm based on an alarm signal from the microcomputer 4, and includes a flip-flop that is set and held by the alarm signal from the microcomputer 4 and reset by the alarm release signal, and a flip-flop that is held in this flip-flop. It has an alarm device that issues an alarm when the alarm signal is received. Reference numeral 7 denotes a display drive circuit which holds and amplifies a distance signal indicating the possible travel distance D from the microcomputer 4 to drive the display 8, and includes a latch that holds the distance signal and amplifies the signal. It has an amplifier. Further, the display 8 has a three-digit numerical display element and constitutes display means for displaying the travelable distance in units of km.

The repeat timer 3 and the microcomputer 4 constitute a calculation processing means for calculating the travelable distance.

Next, the operation of the above configuration will be explained with reference to the calculation flowchart in FIG. FIG. 2 is a calculation flowchart showing calculation processing by the distance calculation control program of the microcomputer 4. As shown in FIG.

First, the arithmetic processing of the microcomputer will be explained according to the arithmetic flowchart shown in FIG. In an automobile equipped with this device, when the key switch is turned on at the start of operation, a stabilized voltage is started to be supplied to the microcomputer 4 from the on-vehicle battery through the stabilized power supply circuit. As a result, the microcomputer 4 starts operating and periodically repeats various calculation processes according to various predetermined programs. In other words, the microcomputer 4 becomes activated by receiving power supply.
In response to an interrupt pulse from the repeat timer 3 that generates an interrupt pulse at a cycle of 1 second, the system starts interrupt processing for calculating the possible travel distance from interrupt step 101 in FIG. Proceed to step 102. In this interrupt counting step 102, "1" is added and counted based on the number of interrupts N=0, which was set to "0" in the initial setting process when the power is turned on, and the process proceeds to the next fuel efficiency data integration step 103. In this fuel efficiency data integration step 103, the fuel efficiency signal from the instantaneous fuel efficiency meter 1 is sampled and input, and the fuel efficiency data is integrated into the previous value, and the first interrupt frequency determination step 10
Proceed to step 4. This first interrupt count determination step 104
Then, it is determined whether the number of interrupts N counted in the interrupt counting step 102 is 60 or more, and when the determination becomes NO, the second
The process advances to step 105 for determining the number of interruptions. In this second interrupt count determination step 105, it is determined whether or not the interrupt count N is 10 or more.
When the answer is NO, the interrupt processing is finished and the process proceeds to return step 115, but when the judgment is YES, the process proceeds to the next alarm release step 106. In this alarm release step 106, an alarm release signal is generated, this interrupt processing is ended, and the process proceeds to return step 115.

On the other hand, when the determination in the first interrupt count determination step 104 is YES, the process advances to the next division step 107. In this division step 107, the total fuel consumption data from 60 samplings, which is the integrated value a of the fuel efficiency data accumulation step 103, is divided by the number of interruptions N (=60) to obtain the average fuel efficiency A.
The process advances to the next average fuel consumption determination step 108. In this average fuel consumption determination step 108, the division step 10
It is determined whether the average fuel consumption A obtained in step 7 is greater than "0", and if the determination is YES, the process proceeds to the next remaining fuel amount input step 109. In this fuel remaining amount input step 109, the remaining fuel amount F from the fuel gauge 2 is
The remaining fuel amount signal indicating the amount of fuel is input, and the process proceeds to the next multiplication step 110. In this multiplication step 110, the average fuel consumption A obtained in the division step 107 is multiplied by the remaining fuel amount F input and stored in the remaining fuel amount input step 109 to obtain the possible travel distance D, and the next distance is displayed. Proceed to step 111. In this distance display step 111, a distance signal indicating the drivable distance D is outputted and applied to the display drive circuit 7, and the drivable distance D is displayed numerically on the display 8. After passing through this display step 111, distance determination step 1
Proceed to step 12. In this distance determination step 112, the drivable distance D obtained in the multiplication step 110 is
If the determination is YES, the process proceeds to the next alarm step 113, but if the determination becomes NO, the alarm step 1 is executed.
The process does not proceed to step 13, but proceeds to the next reset step 114. Further, the reset step 114 is reached after the alarm step 113, and also when the determination in the average fuel consumption determination step 108 becomes NO. In this reset step 114, the number of interruptions N and the fuel consumption data integrated value a are both set to "0", and the process proceeds to the next return step 115, where it is set to 1.
After completing the calculation process of the travelable distance D, the microcomputer 4 returns to control calculations for other on-vehicle systems. Thereafter, every time an interrupt pulse from the repeat timer 3 is generated, interrupt step 10 is executed in the same manner as above.
The interrupt processing from step 1 to return step 115 through various calculation steps is repeated to display the drivable distance D numerically on the display 8, and when the drivable distance D becomes less than 20 km, the alarm step 113 is activated. Through the processing, an alarm signal is held in the alarm device 6 to warn that the remaining amount of fuel is low and refueling is necessary.

Next, the overall operation of this automobile in various states will be explained.

First, when the key switch of this car is turned on, the microcomputer 4 receives a stabilized voltage from the stabilized power supply circuit and enters the operating state, and in the first few microseconds, initial settings are made by arithmetic processing in the main routine (not shown). and starts executing control calculation processing for various in-vehicle systems. In this initial setting process, the number of interruptions N = 0 and the fuel consumption data integrated value a = 0.
Initial settings have also been processed.

When the first interrupt pulse from the repeat timer 3 is applied thereafter, the microcomputer 4 temporarily suspends the arithmetic processing of the main routine being executed at that point, and reaches interrupt step 101 to start interrupt processing. Then, the process proceeds to interrupt counting step 102, where the number of interruptions N becomes N=0+1=1, and the process proceeds to fuel efficiency data integration step 103. In this fuel efficiency data integration step 103, the fuel efficiency signal from the instantaneous fuel efficiency meter 1 is input, and the fuel efficiency signal is integrated to the initial value a=0 according to the initial setting, but the car is stopped immediately after the key switch is turned on. Therefore, the fuel efficiency signal is "0", and even if this fuel efficiency signal is integrated, the integrated value a remains "0" and does not change, and the process proceeds to the next step 104 for determining the number of interruptions. . At this time, since the number of interrupts N counted in the interrupt counting step 102 is "1",
The judgment as to whether or not the number of times has been reached is NO, and the second judgment is made as to whether or not the number of times has been reached 10.
The process proceeds to step 105 for determining the number of interruptions, but the judgment is also NO, and the process proceeds to return step 115.
After completing the interrupt process of several milliseconds due to the first interrupt pulse, the control calculation for other in-vehicle systems in the main routine that was temporarily interrupted due to the interrupt pulse is resumed.

Subsequently, when a second interrupt pulse is applied from the repeat timer 3 one second after the generation of the first interrupt pulse, the microcomputer 4 temporarily suspends the arithmetic processing of the main routine currently being executed. Then, the interrupt step 101 is reached and interrupt processing is started.
Proceed to interrupt counting step 102 and count the number of interrupts N
is set to N=1+1=2, and the process proceeds to fuel consumption data integration step 103, where the value a=0 in the previous interrupt process is set.
The current data "0" is integrated, and the new integrated value a becomes "0", and the process proceeds to the first interrupt count determination step 104, and when the result is NO, the process proceeds to the second interrupt count determination step 105. Proceed to , and the judgment is NO
The process then proceeds to return step 115, and the interrupt processing by the second interrupt pulse is completed.

Then, the same interrupt processing using the interrupt pulse from the repeat timer 3 is repeated, and the interrupt pulse is
When the 10th interrupt occurs, the number of interrupts N in the interrupt counting step 102 becomes N=0, and therefore, after passing through the fuel consumption data accumulation step 103 and the first interrupt number determining step 104, the second interrupt number determining step 105 The judgment is reversed from NO to YES, and the alarm is released in step 10.
Proceed to step 6. In this alarm release step 106, an alarm release signal is applied to the alarm device 6, and the process proceeds to return step 115. At this time, an alarm release signal is applied to the alarm device 6, and the alarm device 6 is maintained in an inactive state. Then, each time an interrupt pulse from the repeat timer 3 is applied, the process proceeds from an interrupt step 101 to an interrupt counting step 102, a fuel consumption data accumulation step 103, a first interrupt count determination step 104,
Interrupt counting is continued by repeating the interrupt process through the second interrupt count determination step 105, the alarm release step 106, and the return step 115.

In this state, even if the engine is started and becomes idling, if the vehicle has not yet started driving, the fuel efficiency signal of the instantaneous fuel efficiency meter 1 remains at "0", so the integrated value of the fuel efficiency data integration step 103 a is maintained at "0". When the 60th interrupt pulse is applied from the repeat timer 3 before the car starts running, the interrupt step 101 is executed.
From there, the process advances to interrupt counting step 102 to calculate the number of interrupts N.
is set to N=60, and after passing through the fuel consumption data integration step 103, the determination in the first interrupt count determination step 104 is reversed from NO to YES, and the process does not proceed to the second interrupt count determination step 105, but the process proceeds to the next division step. Proceed to step 107. In this division step 107, the integrated value a=0 in the fuel efficiency data integration step 103 is divided into N
= 60 to find the average fuel consumption A, but this average fuel consumption A becomes "0". Then, the process proceeds to the next average fuel consumption determination step 108, and it is determined whether the average fuel consumption A is greater than "0", but if the determination is NO, the process proceeds to reset step 114. At this reset step 114, the number of interruptions N and the integrated value a are reset to "0", and the process proceeds to return step 115. In this way, preparations are made for the start of the next cycle of calculation.

Next, when this car is running, the instantaneous fuel consumption meter 1
A fuel consumption signal indicating instantaneous fuel consumption (Km/) corresponding to the driving condition is generated. As a result, the integrated value a gradually increases each time the fuel consumption data integration step 103 is reached based on the interrupt pulse from the repeat timer 3. Then, when the 60 times of integration using the interrupt pulses is completed, the determination in the first interrupt number determination step 104 becomes YES, and the process proceeds to the division step 107. In this division step 107, the fuel consumption data accumulated in the fuel efficiency data accumulation step 103 is calculated.
Accumulated value a of fuel efficiency data from 60 samplings
is divided by the number of interruptions N (=60) to obtain the average fuel consumption A, and the process proceeds to the next average fuel consumption determination step 108. At this time, since the average fuel consumption A does not become "0", the determination in the average fuel consumption determination step 108 becomes YES, and in the remaining fuel amount input step 109, the remaining fuel amount signal indicating the remaining fuel amount F from the fuel meter 2 is output. is input and stored, and the process proceeds to the next multiplication step 110. In this multiplication step 110, the remaining fuel amount F is multiplied by the average fuel consumption A obtained in the division step 107 to obtain the travelable distance D, and the process proceeds to the next distance display step 111. In this distance display step 111, a distance signal indicating the travelable distance D obtained in the multiplication step 110 is applied to the display drive circuit 7.
Thereby, the display drive circuit 7 holds the distance signal and displays the travelable distance D numerically on the display 8.

At that time, for example, if the travelable distance D is 235 km, that value is displayed on the display 8. and,
Proceeding to drivable distance determination step 112, it is determined whether the drivable distance D is 20km or less, but if the determination becomes NO, the process does not proceed to alarm step 113, but proceeds to reset step 114, where the number of interruptions N and fuel consumption data are Reset the integrated value a to "0",
Proceed to return step 115.

Next, if the remaining fuel amount F of the vehicle decreases and the travelable distance D determined at the multiplication step 110 becomes 20 km or less, the determination is made when the travelable distance determination step 112 is reached. but
When the result is YES, the process proceeds to alarm step 113. In this alarm step 113, an alarm signal is set in the alarm device 6 to warn that the remaining fuel amount is low, and the process proceeds to the next reset step 114, where the number of interruptions N and the fuel consumption data integrated value a are set to "0". Then, the process proceeds to return step 115. Thereafter, the alarm from the alarm device 6 continues at the interrupt step 101 until the number of interrupt pulses from the repeat timer 3 reaches 10.
From then, interrupt counting step 102, fuel consumption data integration step 103, first interrupt count determination step 10
4. Perform and maintain the interrupt processing through the second interrupt count determination step 105 to the return step 115, and when the number of interrupt pulses from the repeat timer 3 reaches 10, the second interrupt count determination step is performed. Step 105
The determination is reversed from NO to YES, and the process proceeds to alarm release step 106, where an alarm release signal is applied to the alarm device 6, the alarm signal is released, and the generation of the alarm is stopped. Thereafter, when the travelable distance D becomes less than 20 km, the alarm device 6 will issue an alarm intermittently for 10 seconds at 1-minute intervals.

Therefore, it is possible to sample the fuel consumption 60 times during one minute of driving, calculate the average fuel consumption A, and calculate and display the possible travel distance D based on the remaining fuel amount F at that time.
can be efficiently processed together with control calculations for other in-vehicle systems.

In the above-described embodiment, the distance that can be traveled by an automobile is calculated and displayed, but the distance that can be traveled by other vehicles may be calculated and displayed.

Further, although the instantaneous fuel consumption meter 1 is shown as the fuel consumption detection means, the signals of the traveling speed and fuel consumption may be inputted to a microcomputer and the fuel consumption may be determined through calculation processing by this microcomputer.

Although the fuel meter 2 is shown as the fuel detection means, the remaining amount of fuel may be determined by sequentially subtracting the fuel consumption signal from the value set at the time of refueling in a microcomputer.

Further, although the numerical display 8 is shown as a display means exclusively for displaying the remaining distance, a display device that selectively displays various information in response to a requested operation is used, and one of the pieces of information is the remaining distance. may be displayed.

In addition, in order to sample the fuel efficiency, a periodic interrupt pulse is applied to the microcomputer 4 from the repeat timer 3, and the possible travel distance is calculated by the interrupt processing. The repetition timer 3 can be omitted by providing a normal processing program that inputs fuel consumption data periodically.

Furthermore, although instantaneous fuel consumption in the unit of Km/ is used as the fuel efficiency, fuel consumption in the unit of /Km may also be used. In that case, the remaining fuel amount F is used to calculate the drivable distance D. All you have to do is divide by .

As described above, in the present invention, it is determined whether the average fuel consumption detected by the fuel consumption detection means is 0,
Since we have a prohibition means that prohibits the calculation of the drivable distance based on the average fuel consumption when it is determined that the drivable distance is 0, the drivable distance display does not become 0 even when idling continues, making the driver feel uncomfortable. This has the excellent effect of being able to display the drivable distance without causing any damage.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the drivable distance display method and apparatus according to the present invention, and FIG. 2 is a calculation flowchart showing the calculation processing of the microcomputer in FIG. 1... Instantaneous fuel consumption meter, 2... Fuel gauge, 3... Repeat timer, 4... Microcomputer, 7... Display drive circuit, 8... Display device.

Claims (1)

[Scope of Claims] 1. A fuel consumption detection means for detecting an average fuel consumption based on information on the travel distance and fuel consumption of a vehicle; a fuel detection means for detecting the remaining amount of fuel in the vehicle; a calculation means for calculating a travelable distance based on the detected average fuel consumption and the remaining amount of fuel detected by the fuel detection means; a display means for displaying the travelable distance calculated by the calculation means; and a display means for displaying the travelable distance calculated by the calculation means; A drivable distance display device comprising: a prohibition means for determining whether or not a detected average fuel consumption is 0, and when determining that it is 0, prohibiting the calculating means from calculating a drivable distance based on the average fuel consumption. 2. The drivable distance display device according to claim 1, wherein the fuel efficiency detecting means repeatedly detects the immediately preceding average fuel consumption based only on the immediately preceding operating distance and fuel consumption information. 3. The fuel efficiency detection means includes an instantaneous fuel consumption detection means for detecting momentary instantaneous fuel consumption based on the travel distance and fuel consumption of the vehicle, and repeats sampling of the fuel efficiency signal from the instantaneous fuel consumption detection means at a predetermined period. and, when a predetermined number of fuel efficiency data are obtained through the sampling, an average fuel consumption calculation means for calculating the average fuel consumption based on the predetermined number of fuel consumption data. Distance display device.