JPS6030430A - Fuel consumption indicator - Google Patents

Abstract

PURPOSE:To indicate the quality of fuel consumption relatively by comparing the rate of fuel consumption indicated by the engine revolution in the present gear position and engine torque thereof with the rate of fuel consumption in any other assumed gear position on the iso-horsepower curve. CONSTITUTION:A Central Processing Unit 11 computes the acceleration alpha of a vehicle. It also estimates whether the present running state is in ZONE1 or ZONE2 depending upon the result of above computation. If the running state is determined to be in ZONE2 of an accelerated running state, the present engine revolution N given from a sensor shall be compared with the predetermined N1, and N2 and the result of comparison shall be determined and displayed in such a way as OK for N less than N1, CAUTION for N larger than N1 but smaller than N2 and NG for N larger than N2.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a fuel efficiency display device that displays the quality of fuel efficiency (fuel consumption rate) of a vehicle.

[Prior art and its problems]

FIG. 1 is a graph for determining the quality of fuel efficiency based on the relationship between engine speed and engine load.

That is, in such a conventional fuel efficiency display device, a predetermined region represented by engine speed N and engine load is determined as good (rOKJ) as shown in FIG.

Since the display is divided into "Caution" and defective (rNGJ) areas, for example, when pitching at point A, NGJ is displayed even though the best point with no other choice is being used. Or, when passing point B while accelerating, there are times when it would be better to have one for better fuel efficiency, and an inconvenience has arisen in which the OK message is displayed even though the actual value is Nq.

[Purpose of the invention]

This invention was made under these circumstances, and instead of displaying fuel efficiency absolutely based on the engine speed and load, it displays it relatively, so to speak, depending on the state of the gear used. The purpose is to eliminate the above-mentioned inconveniences.

[Key points of the invention]

The key point is that if the fuel efficiency expressed by the engine speed and engine torque of the gear used is smaller than the fuel efficiency when other gears are assumed to be used on the equal horsepower line, then it is considered "OK". , when it is large, "NGJ"
The point is that relative display is performed as .

[Embodiments of the invention]

Fig. 2 is a schematic diagram showing an embodiment of the present invention, Fig. 3 is a map used to determine whether the vehicle is in an acceleration zone based on vehicle speed and acceleration, and Fig. 4 is a map based on engine speed N and engine load signal. Maps for determining engine torque T; Figures 5 and 6 are maps for determining fuel efficiency based on the relationship between engine speed and engine torque; Figure 7 is a map for determining fuel efficiency based on the relationship between vehicle speed and engine speed. A map for determining the stage, and Figure 8 is a diagram to explain the operation of Figure 2.
It is a chart.

As shown in FIG. 1, the fuel efficiency display device according to the present invention uses a central processing unit (CPU) such as a microcomputer.
) 11 and a timer 12, and a display unit 2 which displays the output from the unit 1. The engine speed signal N1, the engine load signal, and the vehicle speed signal Cv are input to the console unit 1, and the CPU II performs the following processing based on these signals.

The functional operation will be explained below with reference to FIGS. 3 to 8.

First, the CPU 11 receives a signal issued by the timer 12 at predetermined intervals as an interrupt signal, and outputs a vehicle speed signal CV.
Incorporate. As a result, the vehicle speed signal CV is sequentially sampled and captured at predetermined time intervals. Here, vehicle speed data at time T and T+ΔT are respectively cvT.

Assuming that CvT+ΔT, the acceleration component α of the vehicle can be calculated from these data as shown in the following equation.

Note that an acceleration sensor, a differentiator, or the like can be used to detect the acceleration of ΔCV=CVr+1r−CVTr.

On the other hand, if we measure whether the driving state expressed by the vehicle speed C■ and the acceleration α is a steady running state) l (ZOrLHl) or an accelerated running state g (ZOILE2), it can be expressed as vinegar 3tyJ. has been confirmed. Therefore, a predetermined memory (
By pre-memorizing a map like the one shown in Figure #I\2 in the ZONffl (not shown), the operating state at the time it becomes
or ZONH2.

The process of calculating this acceleration α is indicated by the symbol ■ in FIG.
In addition, based on the processing results, the current operating status 9
N B I K t5 f3 Ka, Z ON E 2
The determination process for determining whether K'io is true or not is executed at O in the same figure. As a result, if it is determined to be ZONE 2 (acceleration running state n), the current engine speed N obtained from a sensor (not shown) is #! 5, the predetermined values Nl*N2 and
If it is smaller than N1, it will be "OK", if it is larger than N1 and smaller than N2, it will be "Caution", and if it is larger than N2, it will be judged as "NGJ" and will be displayed. (See Figure 8 O1■, θ). Note that N1 is the boundary speed of whether or not the "car knock" phenomenon occurs no matter what upshift operation is performed, and N2 is the engine speed at which the "car knock" phenomenon does not occur. Selected by rotation speed. On the other hand, if ZONgl (quasi-steady running state) is determined in Fig. 8@, first, the input signal of the control unit 1 is the engine load signal (for example, the intake air amount for a gasoline engine, or the intake air amount for a diesel engine). Calculate the engine torque T by referring to the engine torque detection map shown in Fig. 4 based on the rack position of the control rack, etc.) and the engine rotation speed signal. ”.This is done because the engine load signal is not necessarily proportional to the engine speed.The engine torque T obtained in this way is compared with a predetermined value TL as shown in FIG. (See Figure 8■)
, if T<TL, the fuel consumption is determined to be ``OK'' and displayed (see Figure 8). Here, the fact that torque T is smaller than TL means that engine braking has been determined. 0 This value of TL means that the vehicle is running at the highest rotation speed on a flat road with no cargo, using the lowest gear. The engine torque is set to be less than or equal to the engine torque TLL at the time. That is, T.L.
<TLI, .=”' (2) In the case of T>TL in FIG. 8, the following processing is further performed.

In ■, the currently used gear is determined from the vehicle speed and engine speed using a gear discrimination map as shown in Figure 7. 1st stage, 2nd stage・
...Represents the final gear position, therefore,
If the values of vehicle speed C■ and engine speed N are in either of these shaded areas, at least the crack is in a "contact" state,
Moreover, it can be seen that one of the gear stages is used.

On the other hand, if the values of vehicle speed C■ and engine speed N are outside the shaded area in FIG. 7, it can be considered that the clutch is in a "disengaged" state.

Figure 8 (■) shows how the clutch is "engaged" in this way.

This is the part that determines whether the clutch is "disconnected", and if it is determined that the clutch is "disconnected", the process advances to the above (2) and the fuel efficiency "OK" is displayed. On the other hand, if the clutch is "engaged", the fuel consumption can be increased as follows.

In other words, when the gear ratio μ is multiplied by a constant as shown below, and the engine speed at the currently used gear is Nn1 and the engine torque is Tn, then on the equihorsepower line (see point X in Figure 6. is approximately proportional to the product of the engine rotational speed and torque.) The engine rotation @ NA i and the engine torque TAi of the changed gear stage can be calculated as shown in the following equation (4) F (5).

Note that this calculation is performed as shown in Figure 8 (■), and the non-zero order is
Fuel consumption rate F(Nn) for the gear currently in use.

Tn) and the fuel efficiency rate F (NAi, TAi) for each other gear stage on the equal horsepower line from the equal fuel consumption curve Y in Figure 6 (see Figure 8 ■), and then compare each fuel efficiency rate. (see Figure 8), if the fuel consumption rate is the minimum in the gear in use, it is judged as "OK", otherwise it is judged as l'-NGJ and displayed respectively (see Figure 8 @, ■). . In addition, in FIG. 6, FL indicates a full load curve.

In this way, the accelerated driving state and the quasi-steady driving state are determined from the vehicle speed and acceleration. In the accelerated driving state, the fuel consumption state is determined from the engine speed, while in the quasi-steady driving state, each fuel efficiency rate on the equal horsepower line is determined. By determining the fuel efficiency status through comparison and displaying each, it is possible to accurately display the fuel consumption status in any case. Note that the order of processes (1) and (2) in FIG. 8 may be reversed.

Also, in the "NGJ" display of G1@ in Figure 8, "NG
It is also possible that convection does not immediately display NGJ, but displays NG'J only after the same rNGJ state continues for several seconds (1 to 4 seconds).In this case,
A "Caution" display may be displayed for a number of seconds (1 to 4) in the "Nq" state before the "NG" display is displayed.

〔Effect of the invention〕

As mentioned above, the rotation is high as when riding on the expressway.

Even when driving under high load, that is, when there is no other option, conventional equipment
GJ is displayed, but according to the present invention, it is possible to determine that the most fuel efficient point is being used to obtain the required horsepower and display l'-0KJ.
The conventional inconveniences can be solved. Also, when used in conjunction with the shift up/down instruction function, the fuel consumption "OK" display may appear (during acceleration) even though the shift up instruction is issued, or the shift operation instruction may not be issued. Since it is possible to eliminate the inconvenience of displaying the fuel efficiency of 1'-NGJ (during pitching), it is possible to achieve significant fuel-saving driving.

[Brief explanation of the drawing]

Rattan Figure 1 is a graph for determining whether fuel efficiency is good or bad based on the relationship between engine load and rotational speed, Figure 2 is a schematic diagram showing an embodiment of this invention, and Figure 3 is a graph for determining acceleration driving zones based on vehicle speed and acceleration. Figure 4 is a map to calculate engine torque from the engine rotation speed and engine load. Figures 5 and 6 are maps to calculate fuel efficiency from the relationship between engine rotation speed and engine torque. 7th map to judge the quality of
The figure is a map for determining the gear position from the relationship between vehicle speed and engine rotational speed, and FIG. 8 is a 70-chart for explaining the operation of FIG. 2. Code explanation 1... Control unit, 2...
Display unit, 11...Central processing unit (CPU
), 12... Timer agent Patent attorney Akio Namiki Agent Patent attorney Kiyoshi Matsuzaki

Claims (1)

[Claims] - A vehicle speed sensor that detects the vehicle speed, an engine speed sensor that detects the engine speed, an engine load sensor that detects the engine load, and a unit time that samples the outputs from the vehicle speed sensor at predetermined time intervals. A calculating means for calculating the acceleration component from the amount of change in the vehicle speed and a predetermined memory based on the vehicle speed and the acceleration component to determine whether the current driving state is an accelerated driving state or a quasi-steady driving state. a first fuel efficiency determining means that determines a fuel efficiency state by comparing the engine speed with a predetermined set value when it is determined that the vehicle is in an accelerated traveling state; When the determination is made, based on the output from each sensor, the fuel efficiency is determined at least at the currently used gear position and at other gear positions on the equihorsepower line, and these are compared with each other to determine the fuel efficiency status. a second fuel efficiency determination means;
, and display means for displaying the determination result by the second fuel efficiency determination means.