JP2011144734A - Fuel consumption evaluating system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel consumption evaluating device capable of calculating fuel consumption with high accuracy despite its simple configuration. <P>SOLUTION: This fuel consumption evaluating system includes an accelerator opening detecting part 55 for detecting an accelerator opening, a speed detecting part 56 for detecting the engine speed of an engine driven travelling vehicle as a measured speed, a fuel injection amount computing means for calculating a fuel injection amount per predetermined unit from the accelerator opening and the measured speed in accordance with a correlation between an engine speed drop from a reference speed as the engine speed during no load of an engine and a change of the fuel injection amount, created with respect to each accelerator opening, and a fuel consumption evaluating part 54 for evaluating fuel consumption in accordance with the fuel injection amount calculated by the fuel injection amount computing means. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a fuel consumption evaluation system that calculates and evaluates fuel consumption during traveling in an engine-driven traveling vehicle.

  As a device for calculating and displaying the fuel consumption, conventionally, a flow sensor is attached to the fuel pipe and the actual fuel flow is measured to determine the fuel consumption, or the liquid level of the fuel tank is measured. There is a known method for determining fuel consumption. However, an apparatus for accurately performing a short-term fuel flow rate in the fuel pipe is expensive. In addition, it is difficult to calculate the short-term fuel consumption with a certain degree of accuracy from the measurement of the remaining amount of fuel in the fuel tank.

  If the engine-driven vehicle is equipped with an electronically controlled engine, it will be short-term through the fuel injection amount indicated by the common rail, or if it is equipped with an electronic governor-controlled engine, the position of the control rack will be detected. It is possible to calculate the correct fuel consumption. For example, a technique for accurately measuring and displaying the fuel consumption based on the fuel injection amount by the fuel injection control device is known from Patent Document 1, and calculating and displaying the fuel consumption amount from the detection of the position of the control rack. A fuel consumption display device is known from US Pat.

JP 10-197314 A (paragraph number [0076], FIG. 1) JP 2001-164981 A (paragraph number [0007-0013], FIG. 3)

  It is an object of the present invention to effectively calculate fuel consumption and display fuel etc. even in an engine-driven vehicle equipped with a mechanical governor engine, which is not an electronic control engine or an electronic governor control engine. To provide a fuel consumption evaluation system with a simple configuration for evaluating consumption.

  In order to achieve the above object, a fuel consumption evaluation system according to the present invention includes a rotation speed detection unit that detects an engine rotation speed of an engine-driven traveling vehicle as a measurement rotation speed, an accelerator opening detection unit that detects an accelerator opening, The accelerator opening and the measurement based on the correlation between the engine speed drop amount and the fuel injection amount change from the reference rotational speed, which is the engine speed when the engine is not loaded, created for each accelerator opening degree. A fuel injection amount calculating means for calculating a fuel injection amount per predetermined unit from the rotational speed, and a fuel efficiency evaluation section for performing fuel efficiency evaluation based on the fuel injection amount calculated by the fuel injection amount calculating means.

The present invention relates to a fuel injection amount and an engine speed generated based on a characteristic curve obtained by measuring a relationship between a torque range from no load (idling operation) to a maximum load and an engine speed for each accelerator opening. This is based on the knowledge that the fuel injection amount can be estimated from the accelerator opening and the measured rotational speed of the engine.
Therefore, if a correlation for each accelerator opening between the engine speed drop amount from the reference speed that is the engine speed when the engine is not loaded and the fuel injection amount is established and set in the fuel injection amount calculating means, The fuel injection amount per predetermined unit can be calculated from the accelerator opening detected by the accelerator opening detector and the measured rotational speed detected by the rotational speed detector. For this purpose, detection signals such as an accelerator position sensor and a rotation speed detection sensor mounted on a normal traveling vehicle can be used. The calculated fuel injection amount is calculated in accordance with a simple fuel consumption evaluation such as display on a monitor or voice notification in the form of fuel consumption (hereinafter simply referred to as fuel consumption) and a predetermined rule. Hereinafter, it is possible to evaluate whether or not eco-driving is realized.

  In one preferred embodiment of the present invention, the fuel injection amount calculation means is determined by the accelerator opening detected by the accelerator opening detector, and the measured rotational speed and the fuel injection per predetermined unit. A calculation management unit for setting a correlation with the amount, and a calculation execution unit for deriving the fuel injection amount from the measured rotational speed based on the correlation set by the calculation management unit. . In this configuration, the correlation between the measured rotational speed that differs for each accelerator opening and the fuel injection amount per predetermined unit is appropriately selected and set according to the accelerator opening detected by the accelerator opening detector by the arithmetic management unit. Is done. When a correlation suitable for the current accelerator opening is set, the calculation execution unit can derive the fuel injection amount from the measured rotational speed using the set correlation. A correlation for each accelerator opening is created in advance, and when the accelerator opening is adjusted by the driver's operation, the correlation suitable for that accelerator opening is usually calculated by a computer program. The fuel injection amount per predetermined unit is calculated from the measured rotational speeds set inside the means and sequentially input. Therefore, even if the correlation for each accelerator opening is only experimentally created in advance, even if the detection signal for the accelerator opening and the measured rotational speed is input, the sensor signal for the fuel system is not required directly. In addition, the fuel consumption is calculated, and based on the calculated fuel consumption, evaluation of the fuel consumption such as fuel consumption display is performed.

  As a preferred embodiment of the present invention, the correlation set by the arithmetic management unit is a function according to accelerator opening, wherein the measured engine speed is input and the fuel injection amount per engine rotation is output as the fuel injection amount. It is preferable that this accelerator opening-specific function is generated and stored in advance for each predetermined accelerator opening. Since the correlation set by the calculation management unit is configured by a function depending on the accelerator opening, a function, a so-called mathematical expression, should be incorporated in a program or the like for each accelerator opening allocated at intervals that satisfy the required accuracy. Then, a function to be used is determined by the detected accelerator opening, and the fuel injection amount per one engine revolution can be obtained simply by substituting the measured rotational speed into the input variable of the function and calculating the function. At this time, if the function is a linear function, it is convenient because the operation is simplified. If the error that occurs when the correlation of the function is represented by a single straight line cannot be ignored, it is represented by a curve. In other words, a quadratic or higher-order function is used, but in order to make the calculation easier, a function based on accelerator opening is expressed from a straight line of lines, that is, a combination of linear functions defined for each of a plurality of regions. Good.

  The simplest fuel economy evaluation form in the fuel efficiency evaluation unit is the display of fuel consumption per unit time, the display of fuel consumption per mileage, and the level of fuel efficiency obtained from such fuel consumption ( (Eco-driving level) display. However, when the engine-driven traveling vehicle equipped with this fuel consumption evaluation system is a work vehicle equipped with a work machine driven by engine power, a more preferable fuel consumption evaluation form is the work machine other than the fuel injection amount. This is the fuel efficiency evaluation performed using the operation status of No. as a determination condition of the fuel efficiency evaluation rule. When the load applied to the engine by the work implement is large, it is natural that the fuel consumption deteriorates, so the question is whether the load by the work implement is appropriate and whether the fuel consumption is appropriate for the load from the work implement. If a fuel efficiency evaluation rule to be solved is set in advance in the fuel efficiency evaluation section, and a comprehensive fuel efficiency evaluation is performed and displayed as a result of this rule, it is useful information for the driver of the work vehicle.

  It is well known that the fuel consumption has a close relationship with the vehicle speed. However, the driver does not determine the fuel consumption in association with the vehicle speed, and tends to determine the driving state based on only the information on the fuel consumption. In order to avoid this and to encourage driving that is always conscious of fuel consumption and vehicle speed, in a preferred embodiment of the present invention, information on fuel efficiency evaluation by the fuel efficiency evaluation unit is displayed on a monitor together with vehicle speed information of the engine-driven traveling vehicle. The

It is a schematic diagram explaining the principle of the fuel injection amount calculation process employ | adopted with the fuel consumption evaluation system by this invention. 1 is a perspective view of a tractor equipped with a vehicle driving evaluation system according to the present invention. It is an overhead view which shows the control panel area | region containing the steering wheel with which the driving | running part of the tractor was equipped. 1 is a schematic functional block diagram of a vehicle driving evaluation system according to the present invention. It is a functional block diagram of the vehicle control unit utilized with the vehicle driving evaluation system by this invention. It is explanatory drawing which shows the relationship between the flow of the control data in a vehicle control unit, and each function part.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
First, the principle of the fuel injection amount calculation process employed in the fuel consumption evaluation system according to the present invention will be described with reference to FIG. FIG. 1 (a) shows an engine performance curve of a specific engine which is a target of this fuel consumption evaluation system. The horizontal axis is the engine speed and the vertical axis is the torque. The maximum load line shows the engine speed and torque when the braking force (brake) is applied to the engine output shaft as much as possible without causing engine stall. The no-load line indicates the relationship between the engine speed and torque during so-called idling operation when no load is applied to the engine output shaft. The line connecting the maximum load line and the no-load line is the load from this state based on the no-load speed (idling speed) at each throttle opening: A from 0% to 100%. 4 is a characteristic curve for each accelerator opening indicating an engine speed (generally referred to as an engine speed drop amount) that is reduced by applying.

  The fuel injection amount characteristic with the fuel injection amount per rotation of the engine output shaft as the vertical axis instead of the torque value at each engine operating point of the engine performance curve shown in FIG. The curve is shown in FIG. The fuel injection amount characteristic curve indicates that, for each accelerator opening: A, the engine speed drop amount generated by applying a load to the engine output shaft with the engine speed at no load as a reference speed, and the fuel at that time It can be created from the injection amount. Therefore, when the accelerator opening: A is determined as a parameter of this fuel injection amount characteristic curve, one fuel injection amount characteristic curve defined by the specific accelerator opening is specified, and the fuel injection amount Using the characteristic curve, it is possible to derive the fuel injection amount per one rotation according to the engine speed at that time.

Derivation of the fuel injection amount per rotation using the fuel injection amount characteristic curve will be exemplarily described with reference to the chart enlarged in FIG. Here, it is assumed that an accelerator opening degree A set by an accelerator lever or the like and detected by a position sensor or the like is 90%. When it is detected that the accelerator opening: A is 90%, here, a function F _[90] representing the correlation between the engine speed and the fuel injection amount per rotation is set. The subscript in [] indicates the accelerator opening: A, and the function: F _[90] is a relational expression that at least approximately indicates a fuel injection amount characteristic curve with the accelerator opening: A being 90%. Practically, this relational expression: F _[A] is conveniently a linear function or a quadratic function that at least approximately shows the corresponding fuel injection amount characteristic curve. It does not exclude high-order functions. In addition, for example, even if a linear function (linear equation) is adopted, the engine speed region as the definition region is divided into a plurality of regions, and a different function (linear equation) is assigned to each divided region. May be. The plurality of straight line groups, that is, broken lines can be approximated by an actual fuel injection amount characteristic curve.
Returning to the explanation of FIG. 1C, the lower end position of the fuel injection amount characteristic curve indicated by the function F _[90] is during no-load operation, and the engine speed in the operation state is set to the reference rotation. Number: N, where n is the engine speed detected in real time, the change in the drop amount and the change in the fuel injection amount, which is the difference between the reference speed and the detected engine speed, that is, how much engine from the reference speed It can be grasped from the fuel injection amount characteristic curve how much the fuel injection amount changes if dropped. That is, assuming that the detected engine speed is n and the fuel injection amount per revolution is V, this function F _[90] leads to the following relational expression.
V = F _[90] (n)
Thereby, the fuel injection amount: V can be calculated from the detected engine speed: n.

  The present invention will be described below using an embodiment of a fuel consumption evaluation system that adopts the above-described principle of fuel injection amount calculation processing. FIG. 2 is a perspective view of a tractor equipped with this fuel consumption evaluation system. FIG. 3 is an overhead view showing a control panel area including a steering handle provided in the driving section of the tractor. This tractor transmits the power from the output shaft 10 of the engine 1 to the drive wheel 3 via the transmission 2, and also transmits the engine power to an external work machine 4 such as a tilling work machine, which is mounted on the tractor body. It is. The engine 1 is a diesel engine including a rotation controller 11 that adjusts the engine speed by controlling the fuel injection amount using the fuel supplied from the fuel tank 20, and the rotation controller 11 is a mechanical type. Governor type. Further, an accelerator lever 12 for manually setting the engine speed is also connected to the rotation controller 11, and the accelerator opening is changed, that is, the engine speed is changed depending on the operation position of the accelerator lever 12. Is called.

  The fuel consumption evaluation system is substantially constructed in the vehicle control unit 5 which is one of the vehicle-mounted electronic control units. The vehicle control unit 5 includes, as sensors particularly related to the present invention, an accelerator opening sensor 91 that detects the operation position of the accelerator lever 12 to detect the accelerator opening, and the engine output shaft 10 rotational speed. A rotational speed detection sensor 92 is connected to detect the rotational speed as measured. Information on the fuel consumption evaluated by the fuel consumption evaluation system is sent to the display control unit 7 as fuel consumption information. The display control unit 7 generates notification data in an appropriate notification form from the received fuel consumption information. When the notification data is visualization data that is a visual notification, the notification data is sent to a display panel 70 having a liquid crystal display functioning as a front monitor, where fuel efficiency evaluation information is displayed along with engine rotation and the like.

  The vehicle control unit 5 includes, as functional units specifically related to the present invention, an accelerator opening detector 55 that detects the accelerator opening, a rotation detector 56 that detects the engine rotation speed as a measured rotation speed, and an accelerator opening. And a fuel injection amount calculation means 50 for calculating the fuel injection amount per predetermined unit with the measured rotational speed as an input, and a fuel efficiency evaluation unit 54 for performing fuel efficiency evaluation from the fuel injection amount per predetermined unit, software or hardware It is built with both. In this embodiment, the accelerator opening detector 55 detects the accelerator opening that affects the fuel injection amount based on the signal from the accelerator position sensor 91, and the rotation speed detector 56 receives the rotation speed from the rotation speed detection sensor 92. Based on the signal, the measured rotational speed is detected. In addition, the fuel injection amount calculation means 50 and the fuel efficiency evaluation unit 54 are modularized as a fuel efficiency evaluation module as a function part particularly related to fuel efficiency evaluation. The fuel injection amount calculation means 50 is created for each accelerator opening, based on the correlation between the engine rotational speed drop amount from the reference rotational speed that is the engine rotational speed when the engine is not loaded and the change in the fuel injection amount. A fuel injection amount per predetermined unit is calculated from the accelerator opening and the measured rotational speed. As a unit of the fuel injection amount calculated by the fuel injection amount calculation means 50, one rotation of the engine output shaft 10 is preferably used, but is not limited to this.

  The fuel injection amount calculating means 50 determines the correlation between the measured rotational speed and the fuel injection amount per predetermined unit based on the accelerator opening detected by the accelerator opening detector 55 and sets the determined correlation. And a calculation execution unit 53 for deriving the fuel injection amount per rotation from the measured rotation speed based on the correlation set by the calculation management unit 51. In this embodiment, as a correlation between the measured rotational speed and the fuel injection amount per rotation, a function created for each accelerator opening for deriving the fuel injection amount per rotational rotation from the measured rotational speed is used. Therefore, the function created for each accelerator opening is stored in the function storage unit 52, the calculation management unit 51 specifies the function to be used, reads the specified function from the function storage unit 52, This is given to the calculation execution unit 53.

The fuel consumption information output as the evaluation result by the fuel consumption evaluation unit 54 that performs the fuel consumption evaluation from the fuel injection amount calculated by the fuel injection amount calculation means 50 has various forms as listed below.
(1) Monitor display information of fuel consumption (liter) per unit time (for example, 1 hour).
At that time, if the vehicle speed (average speed, working speed, etc.) is displayed at the same time, it is easy to understand the relationship between the fuel consumption and the vehicle speed. Therefore, it is preferable to add the vehicle speed information by the display control unit 7.
(2) Monitor display information of travel distance per unit amount of fuel.
(3) Eco level display according to fuel economy superiority or poorness evaluated based on comparison with average fuel efficiency. For example, when driving with low fuel consumption, for example, a smiley mark or the like is displayed as excellent eco-driving according to the level.
(4) Notification by voice of the fuel consumption information and eco-driving information described above.
(5) Selective notification of fuel efficiency using a lamp or the like.
It is preferable to configure the fuel consumption evaluation unit 54 so as to output any one of the above fuel consumption notification forms or any combination. For example, in the case of a tractor, it is possible to recognize whether the vehicle is traveling on a road or working using a work machine depending on the gear position being used, and therefore fuel consumption information may be selected for a display mode suitable for each.

Next, the mechanism of fuel efficiency evaluation in the fuel consumption evaluation system described above will be described with reference to FIG.
In this fuel consumption amount evaluation system, the fuel injection amount characteristic curve as described in the explanation of the principle of fuel injection amount calculation processing using FIG. 1 is obtained by an experimental measurement method such as a bench test. Further, a function approximating the fuel injection amount characteristic curve for each accelerator opening extending from the no-load state for each accelerator opening to the maximum load state constituting the fuel injection amount characteristic curve is obtained and stored in the function storage unit 52. (# 01). This characteristic curve may be a straight line or a broken line. In addition, when a fuel injection amount characteristic curve by accelerator opening at intervals narrower than the interval of the accelerator opening used for measurement is required, the fuel injection amount characteristic curve itself or a function is generated approximately using an interpolation method. Good.
In the actual fuel consumption evaluation process, the accelerator opening detection unit 55 determines the accelerator opening: A from the operation position of the accelerator lever, and transfers it to the calculation management unit 51 (# 02). The calculation management unit 51 that has received this accelerator opening: A reads a function F ₍₉₀₎ from the function storage unit 52 because A = 90% of the function that matches the value of the accelerator opening: A in this example. Then, it is set in the calculation execution unit 53 (# 03). Further, the rotational speed detection unit 56 determines the measured rotational speed n, which is the rotational speed of the engine output shaft 10, and transfers it to the calculation execution unit 53 (# 04). The calculation execution unit 53 gives the measured rotational speed: n to the set function F ₍₉₀₎ , and calculates the fuel injection amount: V per revolution from the formula: V = F ₍₉₀₎ (n). Then, it is input to the fuel consumption evaluation section 54 as a determination condition for fuel consumption evaluation (# 05). In addition to the fuel injection amount per rotation, the vehicle speed, the gear position, and the work machine operating state are input to the fuel consumption evaluation unit 54 as determination conditions as necessary.

  The fuel efficiency evaluation unit 54 evaluates the fuel efficiency based on the condition input such as the fuel injection amount per rotation and generates the fuel efficiency information as described above (# 06). If the generated fuel consumption information is for monitor display, the fuel consumption information is transferred to the display control unit 7 (# 07). Based on the transferred fuel consumption information, the display control unit 7 generates display data for displaying a suitable display image on the liquid crystal display unit of the display panel 70 and sends it (# 08). In the example of FIG. 6, the image displayed on the display panel 70 is a combination of a horizontal bar in which the smiley mark increases intermittently as the fuel efficiency is improved, and the smiley mark (eco-friendly) of the driver by this display. Driving).

[Another embodiment]
The present invention can employ the following configurations in addition to the above-described embodiments.
(1) In the above-described embodiment, the correlation that can be created by measuring the engine speed drop amount from the reference engine speed that is the engine speed when the engine is not loaded and the change in the fuel injection amount that occurs at that time. As described above, a measurement rotation speed / fuel injection amount function for deriving a fuel injection amount per rotation from a measured rotation speed of the engine output shaft 10 is created for each engine opening, and the measured rotation speed / fuel injection amount for each engine opening is calculated. The function was stored in the function storage unit 52 in advance. Instead of the measured engine speed and fuel injection amount function for each engine opening, a table that can read the fuel injection amount per rotation from the measured engine speed and the engine opening is created as the above correlation, and the fuel You may incorporate in the injection quantity calculating means 50. FIG. That is, in this other embodiment, the function storage unit 52 is made to function as a table having the measured rotational speed and the engine opening as inputs and the fuel injection amount per rotation as an output.
Instead of creating the above correlation by measuring the change in the engine speed drop from the reference speed, which is the engine speed when the engine is not loaded, and the change in the fuel injection amount that occurs at that time, Measure the engine speed curve by adjusting the engine performance curve obtained by measuring the engine speed drop amount from the reference engine speed, which is the engine speed at that time, and the change in the torque generated at that time. It is also possible to create a measured rotational speed / fuel injection amount curve for each engine opening that represents the relationship between the fuel injection amount and the fuel injection amount.
(2) In the above-described embodiment, the accelerator position detector 55 determines the accelerator position based on the signal from the accelerator position sensor 91. However, the detection of the accelerator position is performed at different positions. It is also possible to adopt a configuration in which the accelerator position is determined based on a signal from the sensor, or a configuration in which the accelerator opening determined in another ECU is directly passed to the fuel injection amount calculation means 50. Similarly, in the above-described embodiment, the rotational speed detection unit 56 determines the measured rotational speed based on the signal from the rotational speed detection sensor 82 that detects the rotation of the engine output shaft 82. Is configured to determine the measured rotational speed based on signals from other sensors installed at various positions, or to pass through the engine rotational speed determined by other ECUs as it is to give to the fuel injection amount calculating means 50 It is also possible to adopt a simple configuration.
(3) In the above-described embodiment, the fuel efficiency evaluation unit 54 generates and outputs fuel efficiency information based on a preset rule using the fuel injection amount per revolution as a condition input. The fuel injection amount per rotation is simply output as fuel consumption information, and the behavior of the fuel injection amount per rotation over time is statistically processed, for example, and the processing result is converted into fuel consumption. It can also be configured to output as information.

  The present invention can be used in the technical field of calculating the fuel consumption of an engine-driven traveling vehicle including an engine whose output is controlled by adjusting the accelerator opening.

1: Engine 10: Engine output shaft 4: Work implement 5: Vehicle control unit 55: Accelerator opening degree detection unit 56: Rotational speed detection unit 7: Display control unit 70: Display panel (monitor)
50: Fuel consumption injection amount calculation means 51: Calculation management unit 52: Function storage unit 53: Calculation execution unit 54: Fuel consumption evaluation unit 55: Accelerator opening degree detection unit 56: Revolution detection unit 91: Acceleration position sensor 92: Revolution detection Sensor

Claims (6)

A rotational speed detector for detecting the engine rotational speed of the engine-driven traveling vehicle as a measured rotational speed;
An accelerator position detector for detecting the accelerator position;
Based on the correlation between the engine speed drop amount from the reference engine speed, which is the engine speed when the engine is not loaded, and the change in the fuel injection amount, created for each accelerator opening, the accelerator opening and the measured rotation A fuel injection amount calculating means for calculating a fuel injection amount per predetermined unit from the number;
A fuel efficiency evaluation unit that performs fuel efficiency evaluation based on the fuel injection amount calculated by the fuel injection amount calculation means;
Fuel consumption evaluation system equipped with.   The fuel injection amount calculation means is a calculation management unit that sets a correlation between the measured rotational speed and the fuel injection amount per predetermined unit, which is determined by the accelerator opening detected by the accelerator opening detector. 2. A fuel consumption evaluation system according to claim 1, further comprising: a calculation execution unit that derives the fuel injection amount from the measured rotational speed based on the correlation set by the calculation management unit.   The correlation set by the calculation management unit is a function according to accelerator opening that outputs the fuel injection amount per engine revolution as the fuel injection amount with the measured rotational speed as an input, and the function according to accelerator opening is The fuel consumption evaluation system according to claim 2, wherein the fuel consumption evaluation system is generated and stored in advance for each predetermined accelerator opening.   The fuel consumption evaluation system according to claim 3, wherein the function according to accelerator opening is a combination of linear functions defined for each of a plurality of regions.   The engine-driven traveling vehicle is a work vehicle equipped with a work machine that is driven by engine power, and the fuel consumption evaluation unit uses the operation state of the work machine as a determination condition of the fuel consumption evaluation rule in addition to the fuel injection amount. The fuel consumption evaluation system according to any one of claims 1 to 4.   The fuel consumption evaluation system according to any one of claims 1 to 5, wherein information related to fuel efficiency evaluation by the fuel efficiency evaluation unit is displayed on a monitor together with vehicle speed information of the engine-driven traveling vehicle.

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