JPH0332975Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a fuel amount display device for a vehicle that displays the amount of fuel in a fuel tank of a vehicle such as a motorcycle.

(Prior Art) FIG. 7 shows an instrument panel of a motorcycle, etc., which is provided with a fuel gauge 73 consisting of a column of light emitting diodes arranged in a vertical line between a speedometer 71 and a tachometer 72. The light emitting diode 75 at the top of the fuel gauge 73 indicates that the fuel tank is full (so-called full tank). This light emitting diode 75
A diode array 74 consisting of eight light emitting diodes following 1 is lit according to the amount of fuel.
When the tank is full, all the light emitting diodes are lit, but as the fuel in the tank decreases, they go out one by one from the top. The light emitting diode 76 at the lowest stage is a light emitting diode that exhibits a so-called empty state indicating that there is very little fuel remaining.

Here, the light emitting diode 74a at the lowest stage of the diode array 74 is in a so-called reserve state, and prompts refueling. That is, as shown in FIG. 8, in a motorcycle, for example, two pipes 83,
84 is arranged, and fuel is supplied to the engine from either one of the pipes via a reserve tank 85. The pipes 83 and 84 are arranged substantially parallel to each other, so that the tip 83a of the pipe 83 is located higher than the tip 84a of the pipe 84. In this case, fuel is initially supplied through the pipe 83 which is at a higher level with a considerable amount of fuel in the tank, but when the fuel amount falls below the suction level (tip 83a) of the pipe 83, the fuel is supplied automatically or manually. Then, the reserve tank 85 is switched to supply fuel through the pipe 84 that can supply fuel from a low level. From such a fuel supply through the high level pipe 83 to the low level pipe 84
The state in which the fuel supply is switched to is called the reserve state. Further, the position of the tip 83a of the pipe 83 is called a static reserve level.

The display of the fuel amount and the reserve state as described above using a light emitting diode is performed by using a light emitting diode to display the output of a unit (described later) including a float installed in the through hole 89 of the other fuel tank 82 in FIG. This is done by inputting it to a general-purpose IC (integrated circuit) for driving.

(Problem to be solved by the invention) As explained above, if the static reserve level can be detected accurately, there will be no problem if the reserve state is displayed accordingly. However, as mentioned above, the fuel level is detected by the float, and since the float oscillates due to vibrations caused by the running of the vehicle, the light emitting diode 74a that indicates the reserve status repeatedly blinks. There was an inconvenience. In this way, due to the waving of the fuel and the swinging of the float, the display may appear as if the fuel amount has not reached the static reserve level even though it is below the static reserve level.
The fuel level at which this phenomenon occurs is called the dynamic reserve level, and there is a certain range.

Therefore, the present invention provides a fuel amount display for vehicles that is capable of properly displaying the fuel amount near the static reserve level without causing the fuel amount display to become unstable when the fuel decreases beyond the static reserve level. The purpose is to provide a fuel quantity display device.

(Means and effects for solving the problem) In order to achieve this object, according to the present invention, a voltage generator that generates a predetermined voltage according to the amount of fuel in the fuel tank 1 having two fuel supply levels is provided. Means 3
and a drive circuit 4 which sends drive outputs to a predetermined number of a plurality of output terminals predetermined according to the magnitude of the output voltage of the voltage generating means 3, and a display based on each drive output of the drive circuit 4. In the fuel amount display device for a vehicle, the display element 51 corresponding to the lowest fuel level to be displayed is the first display below the dynamic reserve level R2. Connection means for connecting the display means to the drive circuit 4 such that the display element 52 corresponding to the next fuel level enters the display state at a second display level exceeding the static reserve level R1. 452.

According to such a configuration, the display of the reserve state is maintained at both the dynamic reserve level and the static reserve level, and the display does not become unstable.

(Embodiments of the invention) Hereinafter, embodiments of the invention will be described with reference to the accompanying drawings.

FIG. 1 shows a system diagram of a vehicle fuel amount display device according to an embodiment of the present invention. In the figure, a float 2 is allowed to float within a fuel tank 1 via a support rod 2a supported at one point. A support rod 2a supporting the float 2 serves as a slider for a potentiometer 3. Therefore, as the float 2 rises and falls according to the amount of fuel in the fuel tank 1, the contact position of the support rod 2a with the potentiometer 3 changes, and the voltage generated at the output end of the potentiometer 3 changes depending on the amount of fuel. It is approximately proportional to.
The potentiometer 3 and the float unit constitute voltage generating means. The voltage generating means may be a combination of a potentiometer and a sliding rod, or various other means.
In particular, it is also possible to detect the fuel level optically and generate a corresponding voltage.

The output voltage of such voltage generation means is
(Integrated circuit) Connect to input terminal 4a of 4. General purpose
IC4 has eight output terminals 44, 441 to 448
It has an input circuit 40, a voltage dividing circuit 41 consisting of eight resistors with equal resistance values, eight comparison amplifiers 42 whose reference voltages are the output voltages of the respective resistors of this voltage dividing circuit 41, and an output of this amplifier 42. It is provided with eight switching circuits 43 each operating at a constant current generating circuit 49 for supplying a constant current to each circuit and a load.

The value of each resistor of the voltage dividing circuit 41 is equal, and the output voltage of each voltage dividing resistor, and thus the reference voltage of the comparator amplifier 42, has a value that changes by an integral multiple of the voltage value determined by one resistor. That is, if the reference voltage of the first amplifier 421 is Vo, then each reference voltage of the second to eighth amplifiers 422 to 428 is nVo (n=2, . . . , 8). Such a comparison amplifier 42 does not send out any output when the input voltage Vi is lower than the reference voltage nVo, but when the input voltage Vi exceeds the reference voltage nVo, the output becomes high level and the corresponding switching circuit 43 is turned on. As a result, a drive output is generated at the corresponding output terminal 44 of the general-purpose IC 4, and the light emitting diode group 5 constituting the display means is energized via the printed connection paths 451 to 458 connected to the output terminal 44. . According to the embodiment of the present invention, the first output terminal 441 is connected to the first light emitting diode 5 through the connection path 451.
1 is connected to the second output terminal 442, but no independent light emitting diode is connected to the second output terminal 442.
They are commonly connected to the first light emitting diode 51 via 52 . At this time, the voltage dividing resistor of the voltage dividing circuit 41 causes the first light emitting diode 51 to dynamically turn on at the first lighting level below the reserve level, but the second light emitting diode 53 It is selected to not turn on at this time, but to turn on at a second lighting level that exceeds the static reserve level.

The third output terminal 443 is connected to the cathode of the second light emitting diode 53 via a connection path 453, and the fourth output terminal 444 is connected to the cathode of the third light emitting diode 54 via a connection path 454. It has been done. The anode of the second light emitting diode 53 is connected to a power source, and the anode of the third light emitting diode 54 is connected to a connection path 453 connecting to the second light emitting diode 53 or to the cathode of the second light emitting diode 53. It has been done. Connection of light emitting diodes 55, 56 to the fifth and sixth output terminals 445, 446, and connection of light emitting diodes 57, 58 to the seventh and eighth output terminals 447, 448
The same applies to the connection.

Next, the operation of this embodiment will be explained with reference to FIGS. 2 and 3.

FIG. 2 shows the relationship between the amount of fuel in the fuel tank 1 and various structural requirements, and a scale 10 representing the amount of fuel is attached. According to this, the float 2 floats and fluctuates from the highest position F, which is over 7 liters, to the lowest position E, which is below 1 liter. During this time, there is a static reserve level R1 near 3 liters, which is the opening of the upper pipe 83, and
There is a dynamic reserve level R2 ranging from 1.5 to 2 liters. Below these reserve levels is the opening of the lower pipe 84.

FIG. 3 shows the relationship between the amount of fuel in the fuel tank 1 and the number of light-emitting diodes lit. That is, the +X direction of the XY axis represents the number of light emitting diodes lit, the -X direction represents the height of the float 2 from the tank bottom, the +Y direction represents the amount of fuel, and the -Y direction represents the lowest position E of the float arm 2a. The deflection angle from Therefore, according to curve 31 in FIG. 3, float 2 floats at a height corresponding to the amount of fuel, and at this time, float arm 2a exhibits a deflection angle as shown by curve 32. Therefore, it is possible to know the deflection angle of the float arm 2a and the voltage generated by the potentiometer 3 according to the amount of fuel, and the curve 33
The number of light-emitting diodes to be lit can be determined according to the deflection angle as shown in FIG. As a result, curve 3
4, it is possible to obtain the number of light-emitting diodes that are lit according to the amount of fuel.

By the way, according to this embodiment, the first and second output terminals 441 of the light emitting diode drive circuit 4,
442 are connected in common, and the values of the voltage dividing resistors that are equal to each other are also predetermined, so that the lighting level of the light emitting diode that lights up first, that is, the first light emitting diode 51, is below the dynamic reserve level R2. and the second light emitting diode 5
The lighting level 2 is set above the static reserve level R1. Therefore, if we consider the case where the fuel decreases, all seven light emitting diodes are lit at first, but as the fuel decreases by a certain amount, the light emitting diodes turn off, and this state is the second one. The light emitting diode 52 continues until the light emitting diode 52 goes out. After this, the period during which the first light emitting diode 51 is lit is longer than the period during which the other light emitting diodes are lit in terms of the rate of fuel reduction. That is, the light emitting diode 51 continues to be lit even if the amount of fuel decreases by the same amount of fuel that was previously required to turn off one light emitting diode. In this way, the first light-emitting diode lights up at a level below the dynamic reserve level (fuel-poor position), and the next second light-emitting diode lights up at a level above the static reserve level (fuel-rich position). Since the diode lights up, the display will not flicker or become unstable near the reserve level.

FIG. 4 shows a fuel tank according to another embodiment of the present invention. According to this embodiment, when there is a constricted part in the fuel tank 1 and the fuel amount and the number of light-emitting diodes do not have a linear relationship as shown in FIG. 5a, this is attempted to be improved. It is something. According to this embodiment, as shown in FIG.
In the light emitting diode drive circuit 4 similar to the embodiment shown in FIG.
The output terminals 444 of the two are commonly connected. According to such a configuration, the period during which the third light emitting diode 53 is lit is longer than other light emitting diodes compared to the fuel change rate, and the linear relationship between the number of light emitting diodes lit and the amount of fuel is maintained. is improved as shown in FIG. 5b.

Note that in each of the above embodiments, the drive circuit 4
By assembling the fuel amount display device as a general-purpose IC together with each light emitting diode on a printed circuit board on which desired connection paths are formed, it is easy to form the vehicle fuel amount display device itself into a unit. Furthermore, in each of the above embodiments,
Although the case where the display means is a light emitting diode has been described, various display means can be used depending on the case, such as a liquid crystal or a cathode ray tube, and the present invention can be applied to any case. Furthermore, in addition to selecting the voltage dividing resistors of the voltage dividing circuit in the drive circuit and the connection relationship of the output terminals, each reserve level can also be adjusted to suit the purpose of the present invention when assembling the fuel tank.

(Effects of the invention) According to the invention, by setting the display levels of the display means in sequence across the static reserve level and the dynamic reserve level as described above, it is possible to stably display the amount of vehicle fuel. A display device can be obtained. In particular, according to the vehicle fuel amount display device according to the present invention, the display level is set by commonly connecting the output terminals of the drive circuits using the connecting means, so general-purpose ICs can be effectively utilized and an inexpensive circuit configuration is possible. It is.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of a fuel amount display device for a vehicle according to an embodiment of the present invention, and FIG. 2 is a conceptual diagram of main parts for explaining the operation of the fuel amount display device for a vehicle according to an embodiment of the present invention. FIG. 3 is a characteristic diagram for explaining the operation of the vehicle fuel amount display device according to the embodiment of the present invention;
FIG. 4 is an explanatory diagram of the main parts of a fuel quantity display device for a vehicle according to another embodiment of the present invention, and FIG. 5 is a diagram for explaining the operation of a fuel quantity display device for a vehicle according to another embodiment of the present invention. 6 is a system diagram of a vehicle fuel quantity display device according to another embodiment of the present invention, and FIG. 7 is a general configuration diagram of an instrument panel for explaining the conventional device.
FIG. 8 is a general configuration diagram of a fuel tank for explaining a conventional device. In the drawing, 1 is a fuel tank, 2 is a float, 3 is a voltage generating means, 4 is a drive circuit, 5 is a display means, 41 is a voltage dividing circuit, 42 is a comparison amplifier, 44
is an output terminal, 45 is a connection means, R1 is a static reserve level, and R2 is a dynamic reserve level. Note that the same reference numerals in each figure indicate similar objects.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) Voltage generating means that generates a predetermined voltage according to the amount of fuel in a fuel tank having two fuel supply levels, and a voltage generating means that generates a predetermined voltage according to the amount of fuel in a fuel tank having two fuel supply levels, and a voltage generating means that generates a predetermined voltage according to the output voltage of the voltage generating means A vehicle fuel amount comprising a drive circuit that sends drive output to a predetermined number of a plurality of predetermined output terminals, and a display means having a plurality of display elements that display based on each drive output of the drive circuit. In the display device, the display element corresponding to the lowest fuel level to be displayed is in the display state at a first display level below the dynamic reserve level, and the display element corresponding to the next fuel level is in the display state at a first display level below the dynamic reserve level. A fuel amount display device for a vehicle, comprising a connection means for connecting the display means to the drive circuit so that the display state is at a second display level. (2) Utility Model Registration Scope of Claims 1. In the device according to claim 1, the drive circuit is a general-purpose IC, and the connection means is for commonly connecting the corresponding output terminals of the drive circuit. Characteristic fuel amount display device for vehicles.