JPS5825212B2 - Vehicle mileage display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device that displays a vehicle's drivable distance with respect to the remaining amount of fuel. By using a two-step display to display a highly accurate drivable distance after the amount has decreased to a predetermined value, accidents such as running out of fuel at an unexpected location can be prevented.

Resistance type fuel meter units used in general automobiles have difficulty in accurately determining the remaining fuel level due to factors such as variations in resistance, installation errors, and the complexity of the fuel tank shape. It is safe to say that it displays the approximate amount of fuel remaining.

Therefore, when the remaining fuel level is low, since the bottom shape of the tank is particularly complex, the error in the fuel meter display is large, and the fuel may suddenly run out in an unexpected place. This makes the driver very anxious.

The present invention has been made to address the above-mentioned conventional problems, and will be described below with reference to embodiments shown in the accompanying drawings.

As shown in FIG. 1, the present invention basically includes a first calculating circuit A that calculates the distance that can be traveled with the current amount of fuel from the remaining fuel level signal from an ordinary resistance type fuel meter unit. , a second arithmetic circuit B which is switched over from the first arithmetic circuit when the fuel becomes less than a set value and accurately calculates the travelable distance from the remaining amount of fuel below the set value.

That is, in FIG.
and B via the switching device 2, and the first arithmetic circuit A
A fuel remaining amount signal 3 from a resistance type fuel meter unit commonly used at present, a vehicle speed signal 5 from a vehicle speed sensor, and a fuel consumption flow rate signal 4 are input to the input terminal.

If the fuel in the tank is above a predetermined value, the first arithmetic circuit A side of the switching device 2 is turned on, and the circuit A is activated.

If the average remaining fuel amount within a certain period of time is Q, the fuel flow rate during that time is q, and the average speed is ■, then the fuel consumption flow rate can be calculated by 1, so it is possible to drive with the average remaining fuel amount at that time. The time T is once, and the distance that can be traveled is L = TV - X V ・・・・・・・・・・・・
・・・・・・・・・(1) It can be found by '.

The first arithmetic circuit A performs calculations as shown in equation (1) above from the remaining fuel amount signal (i.e., Q), the vehicle speed signal (i.e., ■), and the fuel consumption flow signal (i.e., Y). The signal a is held in a latch circuit 6, and displayed on a display section 8, such as a light emitting diode, via a decoder 7.

Since the display based on the operation of the first arithmetic circuit A is based on the remaining fuel amount signal from the fuel meter unit, a value that is a rough guide is displayed.

The fuel tank is provided with a predetermined fuel remaining amount detection device 9 that outputs a signal when the remaining fuel amount accurately decreases to a set value (for example, 51 tons remaining), and when the fuel decreases to the J set value, the detection device 9 is activated. The switching device 2 is switched to the second arithmetic circuit B side by the signal.

The second arithmetic circuit B determines the predetermined fuel level Q based on the signal from the predetermined fuel level detection device 9 and the fuel consumption flow rate signal 4'.
The accurate remaining fuel amount is obtained by subtracting the fuel consumption amount q1 from 1, and the accurate remaining fuel amount and the fuel consumption amount q2/' are calculated from the vehicle speed V as in the case of the first calculation circuit A. Qh (1+ L=-XV・・・・・・・・・・・・・・・・・・
. . . (2) -Force- is calculated, a travelable distance signal is generated, and displayed on the display section 8 via the latch circuit 6 and decoder 7.

The display by the second arithmetic circuit B is based on the first arithmetic circuit A.
Unlike in the case of , the remaining fuel amount is the value obtained by subtracting the subsequent 2 fuel consumption amount q1 from the accurately set predetermined fuel remaining amount Q1, and it is calculated because it is based on the accurate remaining fuel amount. The possible travel distance is extremely accurate, and the occupant can accurately recognize how much further the vehicle can travel if the vehicle travels under the same conditions as the vehicle at that time.

Next, specific circuit examples of arithmetic circuits A and B are shown in FIGS. 2 and 3.
This will be explained with reference to the figures.

FIG. 2 shows a specific example of the first arithmetic circuit A, in which the remaining amount of fuel is detected by the resistance change of the resistive fuel meter unit 10, and this is detected by the A-D converter 11 as a pulse signal (for example, 1 pulse 11t). The counter 2 counts the pulse signal, and the n-ary signal converter 13 sends a signal of Q(lt) to the divider 14.

1. The fuel consumption flow rate is determined by counting the number of times the fuel pump 16 is operated, that is, the number of discharges, as a pulse signal by the counter 7, and sending this to the divider 14 as a q/l signal by the n-ary signal converter 18, Based on the remaining amount signal Q and the fuel consumption flow rate signal q/l, the divider 14 calculates Q/l.
Calculate q/l, find the possible running time T, and calculate this T
The signal is input to multiplier 15.

The vehicle speed is detected by a vehicle speed sensor 9 that connects a magnet to the last stage of the transmission and detects the vehicle speed using a pulse signal from a reed relay.This pulse signal is counted by a counter 20 and then converted to an n-ary signal converter 21. As a signal of vehicle speed V,
This is sent to the multiplier 15, where the Q/, /l-T signals input from the divider 14 are multiplied by the vehicle speed signal □, and a signal representing the possible travel distance is output.

22 is a timing pulse generator, and the pulse count time of each counter 2, 17.20 is controlled by the signal of this 22. For example, the pulse signal from the A-D converter 11 is set to 1 pulse 11t, and the vehicle speed is is set so that 1 pulse is 1/cfn/h. In this way, calculations can be easily made without multiplying by constants.

A specific example of the second arithmetic circuit B is as shown in FIG.

In FIG. 3, the fuel consumption flow rate and vehicle speed detection means, signal transmission means, etc. are exactly the same as in the case of the first arithmetic circuit A, and corresponding parts are shown with the same symbols as in FIG. 2 with a dash added. be.

The remaining amount of fuel is determined by the signal Q1 of the n-ary signal generator 23 indicating the remaining amount of fuel, which is sent to the subtracter 25 via the switching circuit 24, based on the signal from the predetermined remaining fuel amount detection device 9 provided in the tank. The counter 26 starts counting the number of fuel discharges from the fuel pump 16' based on the signal from the remaining fuel amount detection device 9, and the n-ary signal converter 27 converts the fuel consumption signal q.
1 is input into the subtractor 25, and by subtracting the signal q1 from the signal Q1, the accurate remaining fuel amount Q is obtained.
1-ql is sent to the divider 14'.

After that, as in the case of Fig. 2, the fuel consumption flow signal q2/l is sent from the fuel pump 16' to the divider 14' and Q
The signal IQ1=T is input into the multiplier 15', and the vehicle speed signal V from the vehicle speed sensor 19' is input into the multiplier 15' to obtain an output signal indicating the accurate travelable distance.

In this case, the timing pulse generator 22' is activated by a signal from the predetermined remaining fuel amount detection device 9.

As described above, according to the present invention, when the remaining amount of fuel in the fuel tank becomes less than a predetermined value, it is possible to accurately display how much distance can be traveled in that state, which can alleviate driver's anxiety. It is extremely effective in eliminating fish odor and preventing accidents such as running out of fuel in unexpected places.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams showing specific circuit examples of the first arithmetic circuit A part and the second arithmetic circuit B part in FIG. 1, respectively. It is a diagram. A...First arithmetic circuit, B...Second arithmetic circuit, 1...Power supply, 2...Switching device,
Meter: Fuel remaining amount signal, 4.4'...Fuel consumption flow signal, 5,5'...Vehicle speed signal, 6...
... Latch circuit, 7 ... Decoder, 8.
. . . Display section, 9 . . . Predetermined fuel remaining amount detection device.

Claims (1)

[Scope of Claims] 1. A first calculation circuit is provided that calculates the travelable distance from the fuel remaining amount signal obtained from the Tsuyuel meter unit for operating the Tsuyuel meter, the fuel consumption flow rate at that time, and the vehicle speed, and the fuel in the Tsuyuel tank is A first step that calculates the travelable distance from the fuel remaining amount obtained by subtracting the consumed fuel amount from the predetermined fuel remaining amount detected by the predetermined fuel remaining amount detection device that is activated when a certain set value is reached, the fuel consumption flow rate at that time, and the vehicle speed. A second arithmetic circuit is provided, and configured so that the first arithmetic circuit is switched to the second arithmetic circuit by the operation of the predetermined remaining fuel amount detection device, and when the remaining fuel amount is equal to or higher than the set value, the first arithmetic circuit is switched. The approximate drivable distance of a vehicle is displayed by a second arithmetic circuit, and when the remaining fuel level falls below a set value, the drivable distance is switched to a highly accurate drivable distance display by a second arithmetic circuit. Display device. 2 The first calculation circuit divides the fuel remaining amount signal by the fuel consumption flow signal obtained from the number of fuel discharges of the Tsuyuel pump, connects a magnet to the final stage of the transmission, activates a reed relay, and generates a vehicle speed pulse. The vehicle speed signal of the vehicle speed sensor configured as above is multiplied to generate an output signal that indicates the possible travel distance, and the second calculation circuit determines the predetermined fuel remaining amount by operating the fuel remaining amount detection device based on the number of times the fuel pump discharges the fuel. In the case of the first arithmetic circuit, the fuel consumption amount signal to be subtracted from the signal and the fuel consumption flow rate signal to be divided by the remaining fuel amount signal are obtained, and the signal obtained by dividing the remaining fuel amount by the fuel consumption flow rate signal is used. 2. The drivable distance display device for a vehicle according to claim 1, wherein the output signal for displaying the drivable distance is generated by multiplying the vehicle speed signal obtained in the same manner as the above.