JP5221046B2 - Fuel consumption display device - Google Patents

Description

  The present invention relates to a technical field of a fuel consumption display device that displays information related to fuel consumption, for example.

  As a device for displaying the driving state of a vehicle, for example, there are devices (hereinafter referred to as “fuel consumption display devices” as appropriate) that display information relating to fuel consumption listed in Patent Documents 1 to 4. For example, Patent Literature 1 and Patent Literature 2 disclose configurations for calculating and displaying fuel consumption based on a fuel consumption rate map or an engine total performance map. Patent Document 3 discloses a configuration for displaying an actual fuel consumption with respect to a reference fuel consumption. Patent Document 4 discloses a configuration that issues a warning when the fuel efficiency is worse than a target value.

JP 2004-60548 A JP 2002-89349 A JP-A-11-220807 JP-A-4-366729

  According to these configurations, the driver can recognize the current fuel consumption or can recognize that the fuel consumption has deteriorated. However, in these configurations, it is not possible to recognize how the vehicle travels improves or deteriorates. In other words, the above-described configuration has a technical problem that the driver cannot intuitively recognize what kind of traveling the fuel efficiency is improved.

  The present invention has been made in view of, for example, the above-described conventional problems. For example, it is an object of the present invention to provide a fuel consumption display device that can display fuel consumption in a more preferable manner to a driver.

  The fuel consumption display device according to the present invention includes a fuel consumption calculation unit that calculates a current fuel consumption, an estimation unit that estimates a rate of change of the fuel consumption when the current vehicle speed fluctuates based on the calculated current fuel consumption, Display means for displaying the estimated rate of change in fuel consumption in association with the current change in vehicle speed.

  According to the fuel consumption display device of the present invention, for example, based on the current fuel consumption calculated from the fuel injection amount from the injector and the vehicle speed, the rate of change in fuel consumption when the vehicle speed fluctuates from the current vehicle speed (specifically, ) Is estimated, and the estimated rate of change in fuel consumption is displayed in association with the current change in vehicle speed. More specifically, for example, there is a graph showing the fluctuation of the vehicle speed on one axis (for example, the horizontal axis) and the fluctuation rate of the fuel consumption based on the current fuel consumption on the other axis (for example, the vertical axis). Is displayed.

  As a result, the driver can intuitively or visually recognize how much the vehicle speed changes and how much the fuel consumption improves or deteriorates. For example, the driver can intuitively or visually recognize the energy saving merit by decreasing the vehicle speed and the deterioration of fuel consumption by increasing the vehicle speed. In other words, the driver can intuitively or visually recognize how much the vehicle speed needs to be changed in order to improve fuel efficiency. As described above, since the fuel consumption fluctuation rate when the vehicle speed is changed can be intuitively or visually recognized, the driver can be more actively encouraged to save energy.

  In addition, while the current fuel consumption tends to fluctuate greatly depending on the running state of the vehicle, the fluctuation rate of the fuel consumption based on the current fuel consumption tends not to vary so much. That is, the display content of the current fuel consumption changes frequently and greatly, while the change rate of the fuel consumption does not change the display content frequently or greatly. For this reason, the driver can recognize the variation rate of the fuel consumption more suitably compared to the current fuel consumption in which the display content changes frequently and greatly. That is, according to the present invention, by displaying the rate of change in fuel consumption, it is possible to present information related to fuel consumption in a manner that is easy for the driver to see.

  Of course, the fuel consumption fluctuation rate itself may vary greatly depending on the running state of the vehicle. For this reason, it is preferable that the vehicle is in a steady running state from the viewpoint of presenting information related to fuel consumption that is easy to see for the driver. If the vehicle is in a steady running state, not only the rate of change of the fuel consumption but also the current fuel consumption hardly fluctuates so that information related to the fuel consumption can be presented in an easy-to-see manner for the driver.

  In one aspect of the fuel consumption display device of the present invention, the estimation means estimates the fuel consumption fluctuation rate based on a fuel consumption rate map indicating a fuel consumption rate according to a running state of the vehicle.

  According to this aspect, by using the fuel consumption rate map that takes into account the characteristics of the vehicle (or the characteristics of various components constituting the vehicle), it is possible to suitably estimate the fluctuation rate of the fuel consumption.

  In the aspect of the fuel consumption display device that estimates the fuel consumption fluctuation rate based on the fuel consumption rate map as described above, the fuel consumption estimated based on the fuel consumption rate map is calculated when the vehicle is in a steady running state. If the deviation rate from the current fuel consumption is equal to or greater than a predetermined threshold value, a correction means for correcting the fuel consumption rate map may be further provided based on the calculated current fuel consumption.

  With this configuration, the actual vehicle characteristics (that is, the actual fuel efficiency that is actually calculated) and the characteristics indicated by the fuel efficiency map (that is, the current fuel efficiency estimated based on the fuel efficiency map). Even if the difference between them increases, the fuel efficiency can be corrected based on the actual characteristics of the vehicle. For this reason, it is possible to estimate the fuel consumption fluctuation rate with higher accuracy according to the actual vehicle characteristics.

  In another aspect of the fuel consumption display device of the present invention, the estimation means estimates the rate of change of the fuel consumption at a vehicle speed within a predetermined fluctuation range centered on the current vehicle speed.

  According to this aspect, in consideration of the fact that there is almost no sudden acceleration, sudden start, or sudden stop in normal vehicle travel, the current vehicle speed is changed to a vehicle speed that falls within a certain range. If the fluctuation rate of fuel consumption is estimated, the fluctuation rate of fuel consumption within a range that sufficiently covers realistic fluctuations in vehicle speed can be estimated. In other words, since it is not necessary to estimate the rate of change in fuel consumption when the vehicle speed changes to an excessively high or low vehicle speed, the processing load can be reduced, while the fuel efficiency rate when the vehicle speed changes to a realistic vehicle speed is It can be estimated and displayed suitably.

  In another aspect of the fuel consumption display device of the present invention, the display means displays the calculated current fuel consumption in addition to the estimated fuel consumption fluctuation rate.

  According to this aspect, since the current fuel consumption is displayed together with the variation rate of the fuel consumption, the driver can recognize how much the fuel consumption will be changed by changing the vehicle speed. For this reason, the driver can intuitively or visually recognize how much the vehicle speed needs to be changed in order to set the fuel consumption to the target value.

  The operation and other advantages of the present invention will become more apparent from the embodiments described below.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(1) Basic Configuration First, the configuration of a vehicle including an embodiment according to the fuel consumption display device of the present invention will be described with reference to FIG. FIG. 1 is a configuration diagram conceptually showing the basic configuration of the vehicle provided with the fuel consumption display device according to this embodiment.

  As shown in FIG. 1, the cylinder head portion of the cylinder 2 of the engine 1 provided in the vehicle is provided with an injector 11 together with a spark plug (not shown) for each cylinder. Fuel is supplied to the injector 11 via a fuel supply unit and a fuel pipe 15 (not shown).

  Then, the air taken into the combustion chamber 5 via the intake manifold 3 and the intake port and the fuel injected from the injector 11 are mixed in the combustion chamber, and a spark plug (not shown) sparks, so that the combustion chamber 5 The mixed gas burns. The exhaust gas after combustion is discharged to the outside of the engine 1 via the exhaust port and the exhaust manifold 4. As the mixed gas burns in the combustion chamber in this manner, the piston in the combustion chamber 5 repeats reciprocating motion, and the reciprocating motion is converted into a rotational driving force to drive the drive wheels.

  In addition, the vehicle is provided with a vehicle speed sensor 18, an ECU 20, and a display panel 30 that constitutes a specific example of “display means” in the present invention. In particular, the ECU 20 is configured to perform various controls on the engine 1 and the like. In particular, in the present embodiment, the ECU 20 constitutes a specific example of the actual fuel consumption calculation unit 21 that constitutes a specific example of the “fuel consumption calculation means” in the present invention and the “estimation means” in the present invention. The fuel consumption fluctuation rate estimation unit 22, the fuel consumption rate map storage unit 23, the display control unit 24 that constitutes a specific example of the “display unit” in the present invention together with the display panel 30, and the “correction unit” in the present invention The fuel consumption rate map correction part 25 which comprises one specific example is provided. These specific operations will be described in detail below (see FIG. 2 and the like).

(2) Operation Example Next, with reference to FIG. 2, an operation example of the fuel consumption display device according to the present embodiment will be described. FIG. 2 is a flowchart conceptually showing a flow of the operation example of the fuel consumption display device according to this embodiment.

  As shown in FIG. 2, it is first determined by the operation of the ECU 20 whether or not fuel is being injected from the injector 11 (step S101).

  As a result of the determination in step S101, when it is determined that the fuel is not injected from the injector 11 (step S101: No), the operation is terminated. When the operation is finished, it is preferable to restart the operation from step S101 after a predetermined period has elapsed.

  On the other hand, as a result of the determination in step S101, when it is determined that the fuel is being injected from the injector 11 (step S101: Yes), subsequently, the operation of the actual fuel consumption calculation unit 21 causes the fuel from the injector 11 to be injected. Based on the injection amount and the vehicle speed (that is, the vehicle speed) detected by the vehicle speed sensor 18, the current actual fuel consumption value is calculated (step S102). For example, the current actual fuel consumption value is calculated by dividing the integral value of the vehicle speed for a certain period (that is, the travel distance for a certain period) by the integral value of the fuel injection amount from the injector 11 for a certain period.

  Subsequently, the estimated fuel consumption value in the case of the current vehicle speed and the estimated fuel consumption value in the case where the vehicle speed fluctuates from the current vehicle speed are estimated by the operation of the fuel consumption fluctuation rate estimation unit 22 based on the fuel consumption rate map and the R / L line. (Step S103). The fuel consumption rate map and the R / L line are stored in advance in the fuel consumption rate map storage unit 23.

  Here, the fuel consumption rate map and R / L line used for the estimation operation of the estimated fuel consumption value will be described with reference to FIGS. 3 and 4. FIG. 3 is a graph conceptually showing a fuel consumption rate map and an R / L line when the vehicle adopts AT (Automatic Transmission) or MT (Manual Transmission), and FIG. 5 is a graph conceptually showing a fuel efficiency map and an R / L line when a CVT (Continuously Variable Transmission) or a hybrid mechanism is adopted. The R / L line shown in FIGS. 3 and 4 is an R / L line during steady running with the same gear.

  The target output for realizing the desired vehicle speed is uniquely determined according to the characteristics of the vehicle (or the engine 1 or the like). On the other hand, the actual output is determined by the rotational speed of the engine 1 and the torque. Here, the rotational speed of the engine 1 is determined according to the gear (or gear ratio) selected during traveling and the vehicle speed. For this reason, under the condition that the actual output is set to the target output, the torque is inevitably determined if the rotational speed of the engine 1 is determined.

  If the rotational speed and torque of the engine 1 are determined, the fuel efficiency at the vehicle speed is determined based on the fuel efficiency map and the R / L line shown in FIGS. If the fuel consumption rate is determined, the fuel consumption for a certain period can be estimated by performing a calculation process based on the fuel consumption rate. If the fuel consumption for a certain period is estimated, the estimated fuel consumption value is estimated by dividing the integral value of the vehicle speed for a certain period (that is, the mileage for a certain period) by the estimated fuel consumption for the certain period. can do. The fuel consumption fluctuation rate estimation unit 22 performs such calculation on the current vehicle speed and the vehicle speed after the fluctuation, thereby obtaining the estimated fuel consumption value in the case of the current vehicle speed and the estimated fuel consumption value in the case where the vehicle speed fluctuates from the current vehicle speed. Estimated.

  Here, considering that there is almost no sudden acceleration, sudden start or sudden stop in normal vehicle travel, the estimated fuel consumption value when changing from the current vehicle speed to a vehicle speed that falls within a certain range of width Is estimated, it is possible to estimate an estimated fuel consumption value in a range that sufficiently covers realistic fluctuations in vehicle speed. That is, since it is not necessary to estimate the estimated fuel consumption value when the vehicle speed is changed to an excessively high or low vehicle speed, the processing load in the fuel consumption fluctuation rate estimation unit 22 can be reduced, while the vehicle speed changes to a realistic vehicle speed. In this case, the estimated fuel consumption value can be estimated and displayed suitably. In the present embodiment, it is preferable to calculate an estimated fuel consumption value when the vehicle speed fluctuates within a range of about ± 15 km / h or ± 20 km / h centering on the current vehicle speed.

  In FIG. 2 again, subsequently, by the operation of the fuel consumption fluctuation rate estimation unit 22, the estimated fuel consumption value estimated in step S103 is converted into a fluctuation rate with respect to the actual fuel consumption value calculated in step S102 (step S104). Specifically, the estimated fuel consumption value is converted into a variation rate (%) represented by (| actual fuel consumption value−estimated fuel consumption value |) / actual fuel consumption value × 100.

  Thereafter, a graph in which the change rate converted in step S104 and the vehicle speed (more specifically, the increase / decrease amount of the vehicle speed) are associated with each other is displayed on the display panel 30 by the operation of the display control unit 24 (step S40). S105).

  Here, an example of display on the display panel 30 will be described with reference to FIGS. 5 and 6. FIG. 5 is a graph showing a display mode of the change rate of the fuel consumption associated with the vehicle speed, and FIG. 6 is a plan view showing a display mode of the actual fuel consumption value.

  As shown in FIG. 5, a graph may be displayed on the display panel 30 with the horizontal axis as the vehicle speed increase / decrease amount based on the current vehicle speed and the vertical axis as the fuel consumption fluctuation rate based on the actual fuel consumption value. In this case, in order to make the graph easy to see, it is preferable to set the center of the horizontal axis to 0 km / h (that is, the current vehicle speed) and the center of the vertical axis to 0% (that is, the actual fuel consumption value).

  According to such a graph, the driver can recognize that, for example, if the vehicle speed is reduced by 10 km / h, the fuel consumption can be improved by about 13%. Similarly, the driver can recognize that, for example, if the vehicle speed is increased by 10 km / h, the fuel consumption is deteriorated by about 13.5%.

  At this time, the display panel 30 may be configured to simultaneously display the actual fuel consumption value as shown in FIG. According to the display shown in FIG. 6, the driver can recognize that the current actual fuel consumption value is about 10 km / h.

  Of course, the display mode of the change rate of the fuel consumption associated with the vehicle speed shown in FIG. 5 and the display mode of the actual fuel consumption value shown in FIG. 6 are examples, and the increase / decrease rate of the fuel consumption associated with the vehicle speed in other modes. Needless to say, the actual fuel consumption value may be displayed.

  In FIG. 2 again, subsequently, it is determined by the operation of the ECU 20 whether or not the vehicle is in a steady running state (step S106). Here, the “steady running state” indicates, for example, a state in which the fuel injection amount from the injector 11 is constant and the vehicle speed is constant. The steady running state is realized when, for example, auto cruise control is used.

  As a result of the determination in step S106, when it is determined that the vehicle is not in a steady running state (step S106: No), the operation is terminated.

  On the other hand, as a result of the determination in step S106, when it is determined that the vehicle is in a steady running state (step S106: Yes), the actual fuel consumption value (specifically, by the operation of the fuel consumption rate map correction unit 25). Is determined whether or not the degree of divergence between the actual fuel consumption value at the current vehicle speed) and the estimated fuel consumption value (specifically, the estimated fuel consumption value at the current vehicle speed) is large (step S107). Specifically, it is determined whether or not the difference between the actual fuel consumption value at the current vehicle speed and the estimated fuel consumption value at the current vehicle speed is greater than or equal to a predetermined threshold value. If the difference between the actual fuel consumption value at the current vehicle speed and the estimated fuel consumption value at the current vehicle speed is equal to or greater than a predetermined threshold, the degree of deviation between the actual fuel consumption value at the current vehicle speed and the estimated fuel consumption value at the current vehicle speed is large. Determined.

  As a result of the determination in step S107, when it is determined that the difference between the actual fuel consumption value at the current vehicle speed and the estimated fuel consumption value at the current vehicle speed is not large (step S107: No), the operation is terminated.

  On the other hand, as a result of the determination in step S107, if it is determined that the degree of deviation between the actual fuel consumption value at the current vehicle speed and the estimated fuel consumption value at the current vehicle speed is large (step S107: Yes), the fuel consumption rate map correction unit By the operation of 25, the fuel consumption rate map is corrected based on the actual fuel consumption value at the current vehicle speed (step S108). Here, the fuel consumption rate map is corrected so that the actual fuel consumption value at the current vehicle speed substantially matches the estimated fuel consumption value at the current vehicle speed. That is, the fuel consumption rate map is corrected to match the current running state.

  As described above, according to the present embodiment, the change rate of the fuel consumption associated with the vehicle speed is displayed. Accordingly, the driver can intuitively or visually recognize how much the actual fuel consumption value is improved or how much the actual fuel consumption value is improved by changing the vehicle speed. For example, the driver can intuitively or visually recognize the energy saving merit by decreasing the vehicle speed and the deterioration of fuel consumption by increasing the vehicle speed. In other words, the driver can intuitively or visually recognize how much the vehicle speed needs to be changed in order to improve the actual fuel consumption value. As described above, since the fuel consumption fluctuation rate when the vehicle speed is changed can be intuitively or visually recognized, the driver can be more actively encouraged to save energy.

  In addition, while the current fuel consumption tends to vary greatly depending on the running state of the vehicle, the fuel consumption variation rate based on the current actual fuel consumption value does not tend to vary significantly. That is, the display content of the current actual fuel consumption value changes frequently and greatly, while the change rate of the fuel consumption does not change frequently or greatly. For this reason, the driver can recognize the variation rate of the fuel consumption more suitably as compared with the current actual fuel consumption value whose display contents frequently and greatly change. That is, according to the present embodiment, by displaying the rate of change in fuel consumption, it is possible to present information related to fuel consumption in a manner that is easy for the driver to see.

  Of course, the fuel consumption fluctuation rate itself may vary greatly depending on the running state of the vehicle. For this reason, it is preferable that the vehicle is in a steady running state from the viewpoint of presenting information related to fuel consumption that is easy to see for the driver. If the vehicle is in a steady running state, not only the rate of change in fuel consumption but also the current actual fuel consumption value will hardly fluctuate, so that information relating to fuel consumption can be presented in a manner that is easier for the driver to see.

  Further, if the actual fuel consumption value is displayed together with the fuel consumption fluctuation rate associated with the vehicle speed, the driver can recognize how much the fuel consumption is changed by changing the vehicle speed. For this reason, the driver can intuitively or visually recognize how much the vehicle speed needs to be changed in order to set the fuel consumption to the target value.

  In addition, by correcting the fuel consumption rate map when the degree of deviation between the actual fuel consumption value and the estimated fuel consumption value becomes large, the estimated fuel consumption value according to the actual driving state of the vehicle (in other words, more accurate) Can be estimated. In particular, in order to correct the fuel consumption rate map when the vehicle is in a steady running state (that is, when the fluctuation of the actual fuel consumption value is small), the fuel consumption rate map is corrected based on the actual fuel consumption value that is stably calculated. be able to. That is, it is possible to improve the accuracy of correcting the fuel consumption rate map.

  The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist or concept of the invention that can be read from the claims and the entire specification. Moreover, it is included in the technical scope of the present invention.

It is a block diagram which shows notionally the basic composition of the vehicle provided with the fuel consumption display apparatus which concerns on this embodiment. It is a flowchart which shows notionally the flow of the operation example of the fuel consumption display apparatus which concerns on this embodiment. 4 is a graph conceptually showing a fuel efficiency map and an R / L line when a vehicle adopts AT (Automatic Transmission) or MT (Manual Transmission). It is a graph which shows notionally a fuel-consumption-rate map and R / L line in case a vehicle employs CVT (Continuously Variable Transmission) or a hybrid mechanism. It is a graph which matched the change rate of a fuel consumption, and a vehicle speed. It is a top view which shows the display mode of an actual fuel consumption value.

Explanation of symbols

1 Engine 11 Injector 18 Vehicle speed sensor 20 ECU
21 actual fuel consumption calculation unit 22 fuel consumption fluctuation rate estimation unit 23 fuel consumption rate map storage unit 24 display control unit 25 fuel consumption rate map correction unit

Claims (5)

Fuel consumption calculation means for calculating the current fuel consumption;
Estimating means for estimating a fluctuation rate of fuel consumption when the current vehicle speed fluctuates based on the calculated current fuel consumption;
Display means for displaying the estimated change rate of fuel consumption in association with the current change in vehicle speed,
The estimation means estimates the rate of change of the fuel consumption at a vehicle speed within a predetermined fluctuation range centered on the current vehicle speed ,
The display means (i) displays the vehicle speed within the predetermined fluctuation range centered on the current vehicle speed, and (ii) displays the estimated fluctuation rate of fuel consumption within the displayed predetermined fluctuation range. A fuel consumption display device characterized by being displayed in association with each other .   The fuel consumption display device according to claim 1, wherein the estimation unit estimates the fuel consumption fluctuation rate based on a fuel consumption rate map indicating a fuel consumption rate according to a running state of the vehicle.   When the vehicle is in a steady running state and the deviation rate between the fuel consumption estimated based on the fuel consumption rate map and the calculated current fuel consumption is equal to or greater than a predetermined threshold, the calculated current fuel consumption is The fuel consumption display device according to claim 2, further comprising correction means for correcting the fuel consumption rate map based on the fuel consumption rate map.   The fuel consumption display device according to claim 1, wherein the display unit displays the calculated current fuel consumption in addition to the estimated change rate of the fuel consumption.   The display means displays the estimated fuel consumption on a graph in which the vehicle speed is associated with one of the vertical axis and the horizontal axis, and the variation rate of the fuel consumption is associated with the other of the vertical axis and the horizontal axis. The fuel consumption display apparatus according to any one of claims 1 to 4, wherein a change rate is displayed in association with the change in the current vehicle speed.

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