JP2023057009A - Fuel amount calculation device, fuel consumption calculation device, travel management system and program - Google Patents

Abstract

To improve calculation accuracy of fuel amount in a fuel tank of a vehicle or fuel consumption.SOLUTION: A travel management system 1 has a voltage value recording function for recording transition of a voltage value between a fuel sensor 3 in which a resistance value varies depending on increase/decrease of fuel amount of a fuel tank of a vehicle and a battery 4 supplying electric power to the fuel sensor 3. A CPU calculates transition of the fuel amount on the basis of the transition of the voltage value recorded by the voltage value recording function. A voltage value at a point of time when an ignition switch is turned on while oil is not supplied is replaced with a voltage value when the ignition switch is turned off immediately before the point of time, and the voltage value is corrected so that the voltage value linearly shifts from a value after the replacement at the point of time when the ignition switch is turned on to a value when the ignition switch is turned off immediately after the point of time.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fuel amount calculation device, a fuel efficiency calculation device, an operation management system, and a program.

2. Description of the Related Art There is known an operation management device including an input interface for branching and inputting a voltage value inputted from a sensor that detects a fuel amount in a fuel tank of the vehicle as a voltage value to an instrument device of the vehicle (see, for example, Patent Literature 1). In addition, the display is switched so that the remaining amount of fuel (fuel amount) at the time the ignition switch is turned off is stored, and the stored remaining amount of fuel is displayed when the ignition switch is turned on. is known (see, for example, Patent Document 2).

Japanese Patent No. 5668030 JP-A-60-82927

In the operation management system, the resistance value of the fuel sensor changes according to the increase or decrease in the fuel amount in the fuel tank of the vehicle, and the voltage value that changes according to the change in the resistance value is recorded to confirm the transition of the fuel amount. The voltage value fluctuates according to the battery voltage. Specifically, when the battery temperature is low immediately after the ignition switch is turned on, the battery voltage is lower than when a certain period of time has passed since the ignition switch was turned on. As a result, the fuel amount is calculated excessively.

In view of the circumstances described above, the present invention relates to a fuel amount calculation device, a fuel consumption calculation device, an operation management system, and a program capable of improving calculation accuracy of a fuel amount in a fuel tank of a vehicle.

The fuel amount calculation device of the present invention has a voltage value recording function that records changes in the voltage value between a fuel sensor whose resistance value changes as the amount of fuel in a fuel tank of a vehicle increases or decreases and a battery that supplies power to the fuel sensor. In an operation management system comprising: a fuel amount calculation device for calculating the transition of the fuel amount based on the transition of the voltage value recorded by the voltage value recording function, wherein the ignition switch is turned on when fuel is not supplied replacing the voltage value at the point in time with the voltage value at the point in time when the ignition switch is turned off immediately before the point in time, and the voltage value is changed from the value after the replacement at the point in time when the ignition switch is turned on, The voltage value is corrected so as to linearly transition to the value at the time when the ignition switch is turned off immediately after that time.

The fuel efficiency calculation device of the present invention has a voltage value recording function that records changes in the voltage value between a fuel sensor whose resistance value changes as the amount of fuel in a fuel tank of a vehicle increases or decreases and a battery that supplies power to the fuel sensor. In the operation management system, the transition of the fuel amount is calculated based on the transition of the voltage value recorded by the voltage value recording function, and the fuel consumption of the vehicle is calculated based on the calculated transition of the fuel amount. A fuel efficiency calculation device, wherein the voltage value at the time when the ignition switch is turned on when fuel is not supplied is replaced with the voltage value at the time when the ignition switch is turned off immediately before the time, and the voltage value is , the voltage value is corrected so as to linearly transition from the value after replacement at the time when the ignition switch is turned on to the value at the time when the ignition switch is turned off immediately after that time.

The operation management system of the present invention has a voltage value recording function that records changes in the voltage value between a fuel sensor whose resistance value changes as the amount of fuel in a fuel tank of a vehicle increases or decreases and a battery that supplies power to the fuel sensor. An operation management system comprising an on-vehicle device and a fuel amount calculation device that calculates the transition of the fuel amount based on the transition of the voltage value recorded by the voltage value recording function, wherein the fuel amount calculation device is and replacing the voltage value at the time when the ignition switch is turned on when fuel is not supplied with the voltage value at the time when the ignition switch is turned off immediately before that time, and the voltage value is used when the ignition switch is turned on. The voltage value is corrected so as to transition linearly from the value after the replacement at the time when the ignition switch is turned off to the value at the time when the ignition switch is turned off immediately after that time.

The program of the present invention is an operation management having a voltage value recording function for recording changes in the voltage value between a fuel sensor whose resistance value changes according to an increase or decrease in the amount of fuel in a fuel tank of a vehicle and a battery that supplies power to the fuel sensor. In a system, a program for causing a computer to execute a fuel amount calculation process for calculating the transition of the fuel amount based on the transition of the voltage value recorded by the voltage value recording function, the fuel amount calculation process comprising: The voltage value when the ignition switch is turned on while fuel is not supplied is replaced with the voltage value when the ignition switch is turned off immediately before that time, and the voltage value is used when the ignition switch is turned on. It includes a process of correcting the voltage value so as to linearly transition from the value after replacement at the point in time to the value at the point in time when the ignition switch is turned off immediately after the point in time.

According to the present invention, the amount of fuel in the fuel tank of the vehicle and/or the fuel efficiency can be accurately calculated without being affected by the battery voltage before and after the ignition switch is turned on/off.

FIG. 1 is a diagram conceptually showing an operation management system according to one embodiment of the present invention. FIG. 2 is a diagram showing the digital tachograph, the branching unit, the vehicle-mounted meter, the fuel sensor, etc. shown in FIG. FIG. 3 is a block diagram showing functions of the CPU of the digital tachograph and the CPU of the personal computer. FIG. 4 is a graph showing the relationship between the travel distance and the fuel amount when the transition of the fuel amount in the fuel tank is calculated using the measured value of the output voltage _Vout as it is. FIG. 5 is a graph showing the relationship between the travel distance and the fuel amount when the transition of the fuel amount in the fuel tank is calculated by correcting the measured value of the output voltage _Vout . FIG. 6 is a graph showing simplified data of the graphs shown in FIGS. 4 and 5 for comparison. FIG. 7 is a flow chart showing fuel consumption calculation processing of the CPU of the personal computer shown in FIG. FIG. 8 is a flow chart showing the "non-refueling state" determination process included in the fuel consumption calculation process of the CPU of the personal computer shown in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below along with preferred embodiments. It should be noted that the present invention is not limited to the embodiments described below, and can be modified as appropriate without departing from the gist of the present invention. In addition, in the embodiments shown below, there are places where illustrations and explanations of some configurations are omitted, but the details of the omitted technologies are provided within the scope that does not cause contradiction with the contents explained below. , Appropriately known or well-known techniques are applied.

FIG. 1 is a diagram conceptually showing an operation management system 1 according to one embodiment of the present invention. The operation management system 1 shown in this figure is a system for managing the operation of vehicles such as trucks and buses using a digital tachograph 10 mounted on the vehicle. This operation management system 1 has a function of calculating the amount of fuel (remaining amount of fuel) in a fuel tank (not shown) of the vehicle.

The operation management system 1 includes on-vehicle equipment such as a digital tachograph 10 and a branch unit 20, and office equipment such as a recording medium reader/writer 30 and a personal computer 40. The digital tachograph 10 is mounted on a vehicle subject to operation management, and is a digital travel recorder that records information such as speed, travel time, travel distance, fuel amount, etc. of the vehicle in a recording medium M such as a memory card. In particular, in this embodiment, the digital tachograph 10 records, on the recording medium M, changes in voltage value (output voltage V _out described later) corresponding to changes in the amount of fuel in the fuel tank.

A vehicle on which the digital tachograph 10 is mounted includes an onboard meter 2 , a fuel sensor 3 and a battery 4 . The vehicle-mounted meter 2 includes a fuel gauge 21 . The fuel sensor 3 is a resistor provided in the fuel tank, and functions as a variable resistor whose resistance value changes according to the amount of fuel in the fuel tank. The battery 4 supplies electric power to the vehicle-mounted meter 2, the fuel sensor 3, the branch unit 20, the digital tachograph 10, and the like.

FIG. 2 is a diagram showing the digital tachograph 10, the branch unit 20, the onboard meter 2, the fuel sensor 3, etc. shown in FIG. As shown in this figure, the vehicle-mounted meter 2 includes the fuel gauge 21 described above, a CPU (Central Processing Unit) 22, and internal circuits 23, 24, and 25. FIG. Battery 4 is connected to internal circuit 23 . The fuel sensor 3 and the internal circuit 24 are connected in parallel to the internal circuit 23 , and the CPU 22 and the internal circuit 25 are connected in parallel to the internal circuit 24 .

The internal circuit 23 and the fuel sensor 3 constitute a voltage dividing circuit, and the internal circuit 24 and the internal circuit 25 constitute a voltage dividing circuit. The input voltage _Vin in the voltage dividing circuit composed of the internal circuit 23 and the fuel sensor 3 is the voltage of the battery 4, and the output voltage _Vout of the voltage dividing circuit is expressed by the following equation (1).
_Vout =( _R2 /( _R1 + _R2 ))* _Vin (1)
However, R ₁ is the resistance value of the internal circuit 23 and R ₂ is the resistance value of the fuel sensor 3 .

The output voltage V _out of the voltage dividing circuit including the fuel sensor 3 is input to the voltage dividing circuit composed of the internal circuit 24 and the internal circuit 25 . The output voltage V _out ' of the voltage dividing circuit composed of the internal circuit 24 and the internal circuit 25 is expressed by the following equation (2).
V _out ′=(R ₄ /(R ₃ +R ₄ ))×V _out (2)
However, R ₃ is the resistance value of the internal circuit 24 and R ₄ is the resistance value of the internal circuit 25 .

As the amount of fuel in the fuel tank increases, the resistance value _R2 of the fuel sensor 3 decreases, and the output voltage _Vout of the voltage dividing circuit including the fuel sensor 3 decreases. The output voltage V _out ' of the voltage dividing circuit decreases. Conversely, a decrease in the amount of fuel in the fuel tank causes the resistance value _R2 of the fuel sensor 3 to increase and the output voltage _Vout of the voltage dividing circuit including the fuel sensor 3 to rise, thereby causing the internal circuits 24 and 25 to The output voltage V _out ' of the configured voltage divider circuit rises.

The CPU 22 receives an output voltage V _out ' of a voltage dividing circuit composed of internal circuits 24 and 25 . The CPU 22 calculates the amount of fuel in the fuel tank according to the input output voltage V _out ' and transmits it to the fuel gauge 21 . A fuel gauge 21 displays the amount of fuel calculated by the CPU 22 .

The branch unit 20 is connected between the internal circuit 23 and the fuel sensor 3 and receives the output voltage V _out from the voltage dividing circuit including the fuel sensor 3 . The branch unit 20 includes a voltage division/impedance conversion circuit (not shown), and performs impedance matching between the input side and the output side. The output terminal of the branch unit 20 is connected to the input terminal of the digital tachograph 10, and the digital tachograph 10 receives the output voltage _Vout .

The digital tachograph 10 has a recording function for recording various information such as the output voltage _Vout input from the branching unit 20. A recording medium M such as a memory card for realizing the recording function and the recording medium M are It has a slot (not shown) for attachment and detachment.

The digital tachograph 10 records the output voltage V _out input from the branch unit 20 in association with the travel distance of the vehicle every time the ignition switch (not shown) of the vehicle is turned on/off. Here, an ignition switch ON/OFF signal is input to the digital tachograph 10 from a vehicle ECU (Electronic Control Unit) (not shown). The digital tachograph 10 records the output voltage _Vout in the recording medium M in association with the traveling distance of the vehicle and the ignition switch ON/OFF timing each time an ignition switch ON/OFF signal is input.

The recording medium reader/writer 30 shown in FIG. 1 reads various information recorded on the recording medium M. FIG. Various information such as the output voltage V _out read from the recording medium M by the recording medium reader/writer 30 is analyzed by the personal computer 40, and the analysis results are displayed on the monitor. In particular, in this embodiment, the personal computer 40 calculates changes in the amount of fuel in the fuel tank. Specifically, the personal computer 40 calculates changes in the amount of fuel in the fuel tank corresponding to the traveled distance of the vehicle based on the output voltage V _out , the traveled distance of the vehicle, and the information on the on/off timing of the ignition switch of the vehicle. It can be displayed on the monitor.

Here, the resistance value _R2 of the fuel sensor 3, the circuit configuration of the in-vehicle meter 2, the capacity of the fuel tank, and the like differ depending on the vehicle type and vehicle type. Therefore, the output voltage V _out in each of the fuel amount Full state and the fuel amount Empty state differs for each vehicle type and vehicle type. In addition, when the digital tachograph 10 is retrofitted to a vehicle, the fuel in the fuel tank cannot be full or empty. It is not possible to measure the output voltage V _out in each state.

Therefore, in the operation management system 1 of the present embodiment, the output voltage V _out and the capacity value of the fuel tank in each of the fuel amount full state and the fuel amount empty state are determined for each vehicle type and vehicle type. obtained in advance. Then, the personal computer 40 uses the pre-recorded output voltage V _out corresponding to each of Full and Empty and the capacity value of the fuel tank to determine the amount of fuel based on the output voltage V _out detected by the branch unit 20. is calculated.

FIG. 3 is a block diagram showing functions of the CPU 11 of the digital tachograph 10 and the CPU 41 of the personal computer 40. As shown in FIG. As shown in this figure, the CPU 11 of the digital tachograph 10 includes an information acquisition section 111 , a travel distance calculation section 112 and a recording section 113 . The functional units of the CPU 11 operate according to programs stored in a memory (not shown). The information acquisition unit 111 acquires various types of information such as the output voltage V _out , the ignition switch ON/OFF timing, and vehicle speed from the ECU of the vehicle.

When the information acquisition unit 111 acquires a signal instructing the start of operation management, the travel distance calculation unit 112 calculates the travel distance from the travel information such as the vehicle speed of the vehicle acquired by the information acquisition unit 111 . The recording unit 113 records the information acquired by the information acquisition unit 111 and the travel distance information calculated by the travel distance calculation unit 112 on the recording medium M. FIG. Specifically, when the information acquisition unit 111 acquires a signal for instructing the start of operation management, the recording unit 113 records the output voltage V _out and the ignition switch on/off timing acquired by the information acquisition unit 111 as the vehicle running. It is recorded in the recording medium M in association with the travel distance calculated by the distance calculation unit 112 .

The CPU 41 of the personal computer 40 includes an information acquisition section 411 , a fuel amount calculation section 412 and a data generation section 413 . The functional units of the CPU 41 operate according to programs stored in a memory (not shown). The information acquisition unit 411 acquires from the recording medium reader/writer 30 information in which the output voltage V _out , the ignition switch ON/OFF timing, and the travel distance are associated with each other.

The fuel amount calculator 412 refers to a table or formula showing the relationship between the output voltage V _out and the fuel amount, and calculates the fuel amount in the fuel tank from the output voltage V _out acquired by the information acquisition unit 411 . The data creation unit 413 creates fuel data indicating the relationship between the fuel amount calculated by the fuel amount calculation unit 412 and the travel distance, that is, the transition of the fuel amount according to the travel distance.

Here, at a timing soon after the ignition switch is turned on, the temperature of the battery 4 is low and the voltage of the battery 4 (input voltage Vin ₎ will be lower. The output voltage V _out of the voltage dividing circuit including the fuel sensor 3 is affected by voltage fluctuations of the battery 4 . Specifically, this output voltage V _out is detected to be relatively low when the voltage of the battery 4 is relatively low. Therefore, if the output voltage V _out when the ignition switch is turned on (at the time of starting) is used as it is without correction, the fuel amount in the fuel tank is calculated to be excessive. .

FIG. 4 is a graph showing the relationship between the travel distance [km] and the fuel amount [L] when the transition of the fuel amount in the fuel tank is calculated using the measured value of the output voltage _Vout as it is. In order to obtain the data shown in this graph, an actual vehicle was driven, and the output voltage _Vout at the time when the ignition switch was turned on/off was measured and recorded on the recording medium M by the digital tachograph 10 .

As shown in this graph, when the transition of the fuel amount in the fuel tank is calculated using the measured value of the output voltage _Vout as it is, the fuel amount is calculated to be excessive when the ignition switch is turned on. . In addition, the amount of fuel between the time when the ignition switch is turned on and the time when the ignition switch is turned off next to that time is calculated to be excessive.

Therefore, in the operation management system 1 of the present embodiment, the fuel amount calculation unit 412 calculates the output voltage V _out at the time when the ignition switch is turned on by to the output voltage V _out at . Then, the fuel amount calculation unit 412 corrects the output voltage _Vout between the time when the ignition switch is turned on and the time when the ignition switch is turned off next to that time. Specifically, the fuel amount calculation unit 412 determines that the replaced output voltage V _out at the time when the ignition switch is turned on and the output voltage V _out at the next time the ignition switch is turned off are linearly calculated. The output voltage V _out is corrected so as to have a profile connected in a shape.

In the graph of FIG. 4, there is also a phenomenon that the amount of fuel when the ignition switch is turned off exceeds the amount of fuel when the ignition switch is turned off just before that time, even though the vehicle is not refueled. The cause of this phenomenon is the change in the output voltage _Vout due to the vehicle stop posture, the voltage change of the battery 4, and the like. As an example of the fluctuation of the output voltage _Vout due to the parking posture of the vehicle, the resistance value of the fuel sensor 3 fluctuates due to the inclination of the fuel in the fuel tank when the vehicle is stopped on a slope. Variations in the output voltage V _out due to voltage variations in the battery 4 can be exemplified by voltage variations in the battery 3 that occur when the ignition switch is repeatedly turned on and off in a short period of time.

Therefore, in the operation management system 1 of the present embodiment, the fuel amount calculation unit 412 determines that the ignition switch is turned on/off when the fuel is not supplied, and the output voltage V _out at the time when the ignition switch is turned off (at this time when the ignition switch is turned off) is It is determined whether or not the output voltage is lower than the output voltage V _out at the time when the ignition switch was turned off immediately before the time (when the ignition switch was turned off last time). If the output voltage V _out at the current OFF time is lower than the output voltage V _{out at the previous OFF time during non-refueling, the fuel amount calculation unit 412 calculates the output voltage V out at} the current OFF time as the output voltage at the previous OFF time. V _out .

Furthermore, the fuel amount calculation unit 412 corrects the output voltage V _out based on the tilt information of the vehicle transmitted from a detection unit (not shown) that detects the tilt angle of the vehicle, such as an acceleration sensor (not shown).

FIG. 5 is a graph showing the relationship between the travel distance [km] and the fuel amount [L] when the transition of the fuel amount in the fuel tank is calculated by correcting the measured value of the output voltage V _out . In order to obtain the data shown in this graph, an actual vehicle was driven, and the output voltage _Vout at the time when the ignition switch was turned on/off was measured and recorded on the recording medium M by the digital tachograph 10 .

As shown in this graph, when calculating the fuel amount in the fuel tank by correcting the actual measurement value of the output voltage _Vout as described above, the fuel amount at the time when the ignition switch is turned on is properly calculated. be done. In addition, the amount of fuel between the time when the ignition switch is turned on and the time when the ignition switch is turned off before and after that is properly calculated.

In addition, regardless of fluctuations in the output voltage _Vout caused by factors such as the stopping posture (inclination) of the vehicle and repetition of turning the ignition switch on and off in a short period of time, the amount of fuel at the time the ignition switch is turned off is Properly calculated. Also, the amount of fuel between the time when the ignition switch is turned off and the time when the ignition switch is turned on before or after that is properly calculated.

FIG. 6 is a graph showing simplified data of the graphs shown in FIGS. 4 and 5 for comparison. As shown in this graph, the fuel amount calculated using the actual measurement value of the output voltage V _out indicated by the solid line is calculated excessively starting from the ignition switch ON/OFF time. On the other hand, the fuel amount (correction value) calculated using the corrected output voltage _Vout indicated by the dashed line in the graph is calculated appropriately without being affected by the voltage fluctuation of the battery 4 when the ignition switch is turned on. be done.

In addition, the fuel amount calculated using the actual measurement value of the output voltage V _out indicated by the solid line in the graph is affected by factors such as the parking attitude (inclination) of the vehicle and the repetition of turning the ignition switch on and off in a short period of time. It is erroneously calculated according to the variation of the voltage V _out . On the other hand, the fuel amount (correction value) calculated using the corrected output voltage _Vout indicated by the dashed line in the graph is determined by the vehicle stop posture (inclination) and the repetition of turning the ignition switch on and off in a short time. It is properly calculated without being affected by fluctuations in the output voltage _Vout caused by factors such as the following.

FIG. 7 is a flow chart showing fuel consumption calculation processing of the CPU 41 of the personal computer 40 shown in FIG. The processing shown in this flowchart is correction processing of the output voltage _Vout at one point (same traveling distance) where the ignition switch is turned on/off.

In step S1, the fuel amount calculation unit 412 (see FIG. 3) determines whether or not fuel is being supplied during the period from when the ignition switch is turned off to when it is turned on. For example, the fuel amount calculation unit 412 determines whether or not refueling was performed during the period from when the ignition switch was turned off to when the ignition switch was turned on, based on whether the amount of fuel increases by a threshold value or more for the same travel distance. If an affirmative determination is made in step S1, the process proceeds to step S2, and if a negative determination is made in step S1, the process ends without correcting the output voltage _Vout .

In step S2, the fuel amount calculation unit 412 determines that the output voltage _Vout at the time when the ignition switch is turned off (currently turned off) is the output voltage at the time when the ignition switch is turned off immediately before that time (previous time when it was turned off). Determine if it is lower than V _out . Here, if the output voltage V _out at the current OFF time point is lower than the output voltage V _out at the previous OFF time point, the fuel amount _at the current OFF time point would be is calculated to be larger than the fuel amount at the time of the previous OFF. If an affirmative determination is made in step S2, the process proceeds to step S3, and if a negative determination is made in step S2, the process proceeds to step S4.

In step S3, the fuel amount calculation unit 412 replaces the output voltage V _out at the current OFF time with the output voltage V _out at the previous OFF time. As a result, the fuel amount at the current OFF time is calculated to be equal to the fuel amount at the previous OFF time. Further, the fuel amount calculation unit 412 corrects the output voltage V _out so as to linearly transition from the output voltage V _out at the previous OFF time to the post-replacement output voltage V _out at the current OFF time. The process proceeds from step S3 to step S4.

In step S4, the fuel amount calculation unit 412 calculates the output voltage V _out at the time when the ignition switch is turned off (at the time when the ignition switch is turned off) for the same traveling distance as the output voltage V out at the time when the ignition switch is turned on (at the time when the ignition switch _is turned on). Determine whether it is lower than Here, when the output voltage V _out at the ON time is lower than the output voltage V _out at the OFF time, if the output voltage V _out is not corrected, the fuel amount at the ON time will be off even though refueling is not performed. Calculated more than the fuel amount at the time. If an affirmative determination is made in step S4, the process proceeds to step S5, and if a negative determination is made in step S4, the process proceeds to step S6.

In step S5, the fuel amount calculator 412 replaces the output voltage V _out at the ON time with the output voltage V _out at the OFF time. The process proceeds from step S5 to step S6.

In step S6, the fuel amount calculation unit 412 determines whether or not the tilt angle of the vehicle is greater than a threshold value according to the tilt information of the vehicle from when the ignition switch is turned off to when it is turned on. If an affirmative determination is made in step S6, the process proceeds to step S7, and if a negative determination is made in step S6, the process of correcting the output voltage _{Vout ends} .

In step S7, the fuel amount calculation unit 412 corrects the output voltage V _out at the OFF time and the ON time according to the tilt angle of the vehicle. The process of correcting the output voltage V _out is completed as described above, and the fuel amount calculation unit 412 calculates the transition of the fuel amount (that is, the fuel consumption) based on the corrected transition of the output voltage V _out .

As described above, in the operation management system 1 of the present embodiment, the fuel amount calculation unit 412 (see FIG. 3) of the personal computer 40 calculates the output voltage V _out at the time when the ignition switch is turned on, immediately before that time. is replaced with the output voltage V _out when the ignition switch of is turned off. Then, the fuel amount calculation unit 412 linearly changes the output voltage V _out from the value after replacement when the ignition switch is turned on to the value when the ignition switch is turned off immediately after that time. Correct the output voltage V _out so that it transitions. As a result, the fuel amount calculator 412 can properly calculate the fuel amount without being affected by voltage fluctuations of the battery 4 before and after the ignition switch is turned on/off. Therefore, it is possible to appropriately calculate the change in the fuel consumption of the vehicle subject to operation management.

In addition, in the operation management system 1 of the present embodiment, the fuel amount calculation unit 412 determines that the output voltage _Vout at the time when the ignition switch is turned off during non-fueling is It is determined whether or not it is lower than the output voltage V _out . Then, when the output voltage V _out at the time when the ignition switch is turned off while fuel is not being supplied is lower than the output voltage V _out at the time when the ignition switch is turned off immediately before that time, the fuel amount calculation unit 412 determines whether the ignition is turned off. The output voltage V _out when the switch is turned off is replaced with the output voltage V _out when the ignition switch is turned off just before that time. Furthermore, the fuel amount calculation unit 412 corrects the output voltage V _out so as to linearly transition from the value when the ignition switch is turned off immediately before that time to the value after the replacement at that time. . As a result, the fuel amount calculation unit 412 can calculate the fuel amount without being affected by fluctuations in the output voltage _Vout caused by factors such as the stopping posture (inclination) of the vehicle and repetition of turning the ignition switch on and off in a short period of time. It can be calculated properly. Therefore, it is possible to appropriately calculate the change in the fuel consumption of the vehicle subject to operation management.

In addition, in the operation management system 1 of the present embodiment, the recording unit 113 (see FIG. 3) of the digital tachograph 10 stores travel data corresponding to the time when the ignition switch is turned on and the time when the ignition switch is turned off. The distance is recorded, and the transition of the output voltage V _out is recorded in association with the distance traveled. Then, the fuel amount calculation unit 412 of the personal computer 40 calculates the output voltage Vout corresponding to the travel distance recorded by the recording unit 113 when the ignition switch is turned on, and calculates the output voltage V _out corresponding to the travel distance when the ignition switch is turned off. is replaced by the output voltage V _out at that time. As a result, when calculating the fuel consumption in the personal computer 40 as a logistic support terminal, the correspondence information between the ignition switch ON/OFF timing and the travel distance is acquired, and the fuel amount at the ignition switch ON/OFF timing is adjusted appropriately. can be corrected to

FIG. 8 is a flow chart showing the "non-refueling state" determination process included in the fuel consumption calculation process of the CPU 41 of the personal computer 40 shown in FIG. The processing shown in this flowchart is included in the correction processing of the output voltage _Vout at one point (same traveling distance) where the ignition switch is turned on/off. In particular, the determination process of the "non-refueling state" corresponds to the determination process of step S1 in the flowchart shown in FIG.

The determination process starts when the ignition switch is turned off. First, in step S11, the fuel amount calculator 412 (see FIG. 3) records the output voltage _Vout when the ignition switch is turned off. Next, in step S12, the fuel amount calculator 412 determines whether or not the ignition switch is turned on. While a negative determination is made in step S12, step S12 is repeated, and when an affirmative determination is made in step S12, the process proceeds to step S13.

In step S13, the fuel amount calculator 412 records the output voltage _Vout when the ignition switch is turned on. Next, in step S14, the fuel amount calculator 412 calculates the difference ΔV _out between the output voltage V _out when the ignition switch is turned on and the output voltage V _out when the ignition switch is turned off. Next, in step S15, the fuel amount calculation unit 412 determines whether or not the difference ΔV _out calculated in step S14 is less than the threshold value V0 represented by the following equation (3).
V0=(V _Empty -V _Full )×α (3)
where V _Full is the output voltage V _out when the fuel tank is full, V _Empty is the output voltage V _out when the fuel tank is empty, and α is greater than 0 and less than 1. is the coefficient.

α is appropriately set as a threshold value for determining the "non-refueling state", and may be set within a range of 0.1 to 0.3, for example. When α=0.2, V _Full =0.1 V, and V _Empty =1.0 V, _V0 =0.18 V. ” is determined.

If an affirmative determination is made in step S15, correction processing of the output voltage V _out of steps S2 to S7 in FIG. 7 is executed, and if a negative determination is made in step S15, correction of the output voltage V _out is performed. Processing ends without execution.

As a result, regardless of the type of vehicle and the capacity of the fuel tank, it is possible to reliably execute the determination process of the "non-refueling state" and improve the accuracy of fuel consumption calculation.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the above-described embodiments, and may be modified without departing from the scope of the present invention. You can combine techniques.

For example, in the above-described embodiment, the change in the output voltage V _out is recorded _in the recording medium M in association with the traveled distance, and the fuel amount corresponding to the traveled distance is calculated. The data may be recorded in the recording medium M in association with each other, and the fuel amount corresponding to the running time may be calculated.

Further, in the above embodiment, the CPU 41 as the fuel amount calculation device is provided in the personal computer 40, but it may be provided in the digital tachograph 10 or the server. Furthermore, the digital tachograph 10 and the personal computer 40 may be configured to be communicable via a server.

1 : Operation management system 3 : fuel sensor 4 : Battery 10 : Digital tachograph (in-vehicle device)
40 : Personal computer (logistical support terminal, computer)
41 : CPU (fuel amount calculation device, fuel consumption calculation device)
M. : Recording medium R ₂ : Resistance value V _out : Output voltage (voltage value, value)
V _Empty : Output voltage (voltage value when the fuel tank is empty)
V _Full : Output voltage (voltage value when the fuel tank is full)
V0 : threshold (difference)
ΔV _out : difference α :coefficient

Claims (9)

An operation management system having a voltage value recording function for recording changes in a voltage value between a fuel sensor whose resistance value changes according to an increase or decrease in the amount of fuel in a fuel tank of a vehicle and a battery that supplies power to the fuel sensor, wherein the voltage value A fuel amount calculation device that calculates the transition of the fuel amount based on the transition of the voltage value recorded by a recording function,
replacing the voltage value at the time when the ignition switch is turned on while not refueling with the voltage value at the time when the ignition switch is turned off immediately before that time;
The voltage value changes linearly from a value after replacement when the ignition switch is turned on to a value when the ignition switch is turned off immediately after that time. A fuel amount calculation device that corrects the If the voltage value at the time when the ignition switch is turned off while fuel is not being supplied is lower than the voltage value at the time when the ignition switch is turned off immediately before that time, the voltage value at that time is Replace with the voltage value at the time when the ignition switch is turned off immediately before,
2. The fuel according to claim 1, wherein the voltage value is corrected so that the voltage value changes linearly from the value at the time when the ignition switch is turned off immediately before that time to the value at that time. Quantity calculator. The operation management system has an ignition recording function that records the traveled distance or traveled time at the time when the ignition switch is turned on and the time when the ignition switch is turned off,
The voltage value recording function records the transition of the voltage value in association with the running distance or running time,
The fuel amount calculation device stores the voltage value corresponding to the travel distance or travel time when the ignition switch is turned on, which is recorded by the ignition recording function, when the ignition switch is off at the travel distance or travel time. 3. The fuel amount calculation device according to claim 1, wherein the voltage value at the time when the voltage becomes . The difference ΔV _out between the voltage value at the time the ignition switch is turned off and the voltage value at the time the ignition switch is turned on immediately after that time is the 3. The non-fueling state is determined when the difference ΔV out between the voltage value and the voltage value when the fuel tank is empty is less than a value obtained by multiplying the difference ΔV _out by a coefficient greater than 0 and less than 1. fuel amount calculator. An operation management system having a voltage value recording function for recording changes in a voltage value between a fuel sensor whose resistance value changes according to an increase or decrease in the amount of fuel in a fuel tank of a vehicle and a battery that supplies power to the fuel sensor, wherein the voltage value A fuel consumption calculation device for calculating a change in the fuel amount based on the change in the voltage value recorded by a recording function, and calculating a fuel consumption of the vehicle based on the calculated change in the fuel amount,
replacing the voltage value at the time when the ignition switch is turned on while not refueling with the voltage value at the time when the ignition switch is turned off immediately before that time;
The voltage value changes linearly from a value after replacement when the ignition switch is turned on to a value when the ignition switch is turned off immediately after that time. A fuel consumption calculation device that corrects the A vehicle-mounted device having a voltage value recording function that records changes in the voltage value between a fuel sensor whose resistance value changes according to an increase or decrease in the amount of fuel in a fuel tank of the vehicle and a battery that supplies power to the fuel sensor;
An operation management system comprising a fuel amount calculation device that calculates the transition of the fuel amount based on the transition of the voltage value recorded by the voltage value recording function,
The fuel amount calculation device is
replacing the voltage value at the time when the ignition switch is turned on while not refueling with the voltage value at the time when the ignition switch is turned off immediately before that time;
The voltage value changes linearly from a value after replacement when the ignition switch is turned on to a value when the ignition switch is turned off immediately after that time. Operation management system that corrects The vehicle-mounted device has an ignition recording function that records the travel distance or travel time at the time when the ignition switch is turned on and the time when the ignition switch is turned off,
The voltage value recording function records the transition of the voltage value in association with the running distance or running time,
The fuel amount calculation device stores the voltage value corresponding to the travel distance or travel time when the ignition switch is turned on, which is recorded by the ignition recording function, when the ignition switch is off at the travel distance or travel time. 7. The operation management system according to claim 6, wherein the voltage value is replaced with the voltage value at the time when the voltage becomes . 8. The operation management system according to claim 7, wherein the fuel amount calculation device is provided in a rear support terminal capable of inputting the information recorded in the vehicle-mounted device via a recording medium or communication. An operation management system having a voltage value recording function for recording changes in a voltage value between a fuel sensor whose resistance value changes according to an increase or decrease in the amount of fuel in a fuel tank of a vehicle and a battery that supplies power to the fuel sensor, wherein the voltage value A program for causing a computer to execute a fuel amount calculation process for calculating the transition of the fuel amount based on the transition of the voltage value recorded by a recording function,
The fuel amount calculation process includes:
replacing the voltage value at the time when the ignition switch is turned on while not refueling with the voltage value at the time when the ignition switch is turned off immediately before that time;
The voltage value changes linearly from a value after replacement when the ignition switch is turned on to a value when the ignition switch is turned off immediately after that time. A program that includes processing to correct for

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