JPH0313528B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a liquid level meter that accurately displays the remaining amount of liquid.

[Conventional technology]

The liquid level meter that displays the remaining amount of liquid, for example, the remaining amount of fuel in vehicles such as automobiles, is a digital type disclosed in Japanese Patent Application Laid-Open No. 53-35574, or a guideline disclosed in Publication of Utility Model Publication No. 15337-1982. There is an indicator type, but as disclosed in Japanese Utility Model Application Publication No. 53-97649, there is a display section that has a plurality of light emitting bodies arranged in sequence, and a wire that is connected to each of the light emitting bodies of this display section and fixed at a constant rate. A movable contact that is driven by a float that responds to the remaining amount of liquid and contacts the fixed contact group, and selectively lights up the light emitting body of the display according to the remaining amount of liquid. There are also bar graph types that emit light to display the amount of liquid remaining.

[Problem that the invention seeks to solve]

These bar graph type liquid level meters have the advantage of being able to instantly identify the ratio between the amount of remaining liquid and the amount of liquid consumed compared to digital type liquid level meters, and they also have the advantage of being easier to use graphically than pointer type liquid level meters. Although it has the advantage of being able to provide a new and innovative display, the display section is configured to display approximately equal intervals, and in order to improve the accuracy of this display, in particular, the fluid level gauge installed in the vehicle has been designed to provide a fuel starvation warning. In order to achieve this effect, it is desirable to display areas with a small amount of liquid in detail. Although it is fine to increase the number, the display section becomes large in area, which is a problem when space is limited, such as in the case of a vehicle's instrument panel.

[Purpose of the invention]

This invention was devised by focusing on such conventional problems, and is a bar graph type that can display the remaining amount of liquid with high accuracy, and can particularly display areas with low remaining amount of liquid in detail. The purpose is to provide a liquid meter.

[Means for solving problems]

In order to achieve the above object, the present invention includes a detection unit that outputs a voltage according to the remaining amount of liquid in a liquid tank, and a plurality of display segments arranged in a line based on the voltage from the detection unit, which is in a display state. a bar graph type display scale section that is divided into a display segment and a display segment that is in a non-display state to display the remaining amount of liquid and the consumption amount; and a display scale section that is disposed near the display scale section. a display symbol section indicating a state of a display area and a display segment of the non-display state of the display scale section to a display state to enlarge and display the area where the remaining amount of liquid is low, and switch the display symbol section. and a switching section that scales down the scale.

〔Example〕

FIG. 1 is a circuit diagram of a liquid meter according to an embodiment of the present invention, and FIG. 2 is a display example of the liquid meter shown in FIG. In the figure, 1 is a detection unit that outputs a voltage according to the remaining amount of liquid, and is composed of a power supply 101, a sliding contact 102 and a resistor 103 that constitute a potentiometer variable resistor, and a power supply 101 and a resistor. 103 is connected in series with a high potential terminal a and a low potential terminal b, and the sliding contact 102 is coupled to a float (not shown) in a liquid tank (not shown), and when the remaining amount of liquid changes, the float When you move,
A voltage corresponding to the movement of the float, that is, a voltage corresponding to the remaining amount of liquid is applied to the sliding contact 102 and the terminal b.
It occurs in between and outputs.

2 is a comparison section, which includes seven resistors 201 to 207 and six comparison elements 211 to 207 constituting a resistor group.
216, the resistors 201 to 207 are connected in series, and both ends of this series circuit are connected to terminals a and b, respectively.
1,202 is the reference terminal of the comparison element 211,
The midpoint of resistors 202 and 203 is the reference terminal of comparison element 212, the midpoint of resistors 203 and 204 is the reference terminal of comparison element 213, and the midpoint of resistors 204 and 205 is the reference terminal of comparison element 214, and the resistor 205,
The midpoint of 206 is connected to the reference terminal of comparison element 215, the midpoint of resistors 206 and 207 is connected to the reference terminal of comparison element 216, and the sliding contact 10
The output terminals of 2 are connected to the comparison elements 211 to 216, respectively, and the voltage of the power supply 101 is divided by the resistor group, so that the comparison elements 211 to 21 are connected to each other.
Each reference voltage of 6 is set to a different value,
The voltage of the detection unit 1 that outputs a voltage according to the remaining amount of liquid, that is, the comparison voltage of the comparison elements 211 to 216 is larger than the reference voltage, and only the comparison element has an output voltage at a high level and is connected to the subsequent stage. A display scale section (described later) is selectively driven.

Reference numeral 3 denotes a switching section, which consists of a comparison element 301, a PNP type transistor 302 constituting a switch element, and resistors 303 to 305.
3 and 304, both ends of this series circuit are connected to terminals a and b, respectively, and the midpoint thereof is connected to the comparison terminal of comparison element 301,
And, the output terminal of the sliding contact 102 is connected to the comparison element 3.
A resistor 3 is connected to the reference terminal 01, and a resistor 3 is connected between the terminal a and the high potential terminal c of the resistor group of the comparison section 2.
05 is inserted and connected, and a transistor 30 is connected to terminal a.
2, the collector of the transistor 302 is connected to the terminal c, the base of the transistor 302 is connected to the output terminal of the comparison element 301, and the resistor 3
The comparison voltage of the comparison element 301 is set by dividing the voltage of the power supply 101 at 03 and 304, and this voltage is used as a switching point when enlarging and displaying an area with a small amount of liquid on the display scale section (described later). The voltage corresponds to the remaining amount of 7l, and when the remaining amount of liquid decreases below the remaining amount at the switching point, the comparison section 2 in the latter stage is used to enlarge and display the area where there is less liquid.
The reference voltages of the comparison elements 211-216 are lowered by lowering the divided voltages of the resistors 201-207 at a constant rate.

Reference numeral 4 denotes a display scale section that displays the remaining amount of liquid in a bar graph type, and is composed of six display segments 401 to 406 arranged in a row. are connected between the output terminals of comparison elements 211 to 216 of comparison section 2 and terminal b, respectively, and are in a display state when the output voltages of comparison elements 211 to 216 are at a high level, and are in a non-display state when they are at a low level. The former displays the remaining amount of liquid, and the latter displays the consumed amount.

Reference numeral 5 denotes a range switching display section, and a display segment 501 is composed of display elements similar to those of the display segments 401 to 406 of the display scale section 4.
This range switching display segment 501
is the emitter of the transistor 302 and the resistor 305
and is inserted and connected between the switching point and the display state only when the remaining amount of liquid decreases below the switching point remaining amount.

Reference numeral 6 denotes a display symbol section indicating the state of the display area of the display scale section 4, which includes PNP type transistors 601, 602 constituting a switch element and a display element similar to the display elements of the display segments 401 to 406 of the display scale section 4. A display segment 611 composed of
~624, display segments 611~6
17 and display segments 618 to 624 are each formed in a Japanese character shape, and the former is the display segment 401 of the display scale section 4, and the latter is the display segment 401 of the display scale section 4.
The base of the transistor 601 is connected to the output terminal of the comparison element 301 of the switching unit 3, the emitter of the transistor 601 is connected to the power supply terminal d, and the collector of the transistor 602 is connected to the ground. The collector and emitter of the transistor 601 are connected to the terminal d, and the collector is connected to the ground, respectively, and the transistor 601 is turned on only when the remaining amount of liquid is greater than the remaining amount of the switching point.
2 is turned on only when the remaining liquid level decreases below the switching point remaining level, and the display segment 61
1,618,621-623 are transistors 60
Between the collector of 1,602 and ground, display segments 615 to 617, 624 are transistors 601
between the collector and ground of the display segment 612,
613, 619, and 620 are connected between the collector of the transistor 602 and ground, respectively, and when the remaining liquid amount is greater than the remaining amount at the switching point, F is displayed in display segments 611 to 617 as shown in FIG. 2A.
Display segment 611 to display (FULL),
615 to 617 are in the display state, and display segments 618 and 621 to 62 are in a display state to display E (EMPTY) in display segments 618 to 624.
4 is displayed, and when the remaining liquid amount decreases below the switching point remaining amount, 7 (7) is displayed in the display segments 611 to 617 as shown in FIG. 2B.
display segments 611, 615,
616 is in the display state, and the display segments 618 to 624 are in the display state so that 0 (0) is displayed in the display segments 618 to 624.

Next, the operation will be explained.

Assuming that the voltage of the power supply 101 is V, the resistance value of the resistor 103 is R, and the capacity of the liquid tank is 35, the reference voltage V _- of the comparison element 301 becomes V ₊ =V.

In order to enlarge and display areas with low liquid remaining after the remaining liquid level reaches 7,
The resistance values of the resistors 303 and 304 are set so that the voltage V ₊ corresponding to the voltage V + is the comparison voltage of the comparison element 301.

Therefore, the remaining liquid level decreases from 35 to 7.
Until reaching V ₊ < V _- , the output voltage V ₀ of comparison element 301 remains low level, transistor 302 is on, resistor 305 is short-circuited, and the potential of terminal c is approximately V. .

If the resistance value of each of the resistors 201 to 207 is R', the voltage V _1- at the midpoint of the resistors 201 and 202 is 6/7V (voltage corresponding to the remaining amount of liquid 30), and the voltage of the resistors 202 and 203 is The voltage V _2- at the midpoint is 5/7 V (voltage equivalent to 25), the voltage V _3- at the midpoint of resistors 203 and 204 is 4/7 V (voltage equivalent to 20), and resistor 24 , 205 _is 3/7 V (voltage equivalent to 15), voltage V _5- at the midpoint of resistors 205 and 206 is 2/7 V (voltage equivalent to 10), and the resistor The voltage V _6- at the midpoint of the bodies 206 and 207 is 1/7 V (voltage corresponding to 5), and the voltage V 6- at the midpoint of the respective comparison elements 21
1 to 216, and the voltage V _- generated between the sliding contact 102 of the detection unit 1 and the terminal b according to the remaining amount of liquid becomes the comparison voltage V ₊ ' of the comparison elements 211 to 216. ing.

Therefore, when the remaining liquid level is 35 to 30, V ₊ ′ is
Since it is larger than V _1- to _{V 6-} , the comparison element 211
The output voltages 216 to 216 become high level, and the display segments 401 to 406 enter the display state.

When the remaining liquid level is 30 to 25, V ₊ ′ is larger than V _2- to V _6- but smaller than V _1- , so comparison element 2
Only the output voltage of No. 11 becomes low level, and the display segments 402 to 406 remain in the display state, and the display segment 401 becomes the non-display state.

When the remaining amount of liquid is 25 to 20, V ₊ ' is larger than V _3- to V _6- but smaller than V _1- and V _2- , so the output voltages of comparison elements 211 and 212 are low level. Therefore, display segments 403 to 406 are in a display state, and display segments 401 and 402 are in a non-display state.

When the remaining amount of liquid is 20 to 15, V ₊ ' is larger than V _4- to V _6- but smaller than V _1- to V _3- , so the output voltage of comparison elements 211 to 213 is low level. Therefore, display segments 404 to 406 are in a display state, and display segments 401 to 403 are in a non-display state.

When the remaining amount of liquid is 15 to 10, V ₊ ' is larger than V _5- and V _6- but smaller than V _1- to V _4- , so the output voltages of comparison elements 211 to 214 are low level. Therefore, display segments 405 and 406 are in a display state, and display segments 401 to 404 are in a non-display state.

When the remaining liquid level is 10 to 5, V ₊ ' is larger than V _6- but smaller than V _1- to V ⁵ _- , so the output voltages of comparison elements 211 to 215 are low level, and the display segment Only segment 406 is in a display state, and display segments 401 to 405 are in a non-display state.

However, when the remaining amount of liquid is 10 to 5, when it reaches 7, the relationship becomes V ₊ > V _- , the output voltage of comparison element 301 becomes high level, transistor 302 turns off, and resistor 305 returns. .

If the resistance value of the resistor 305 is set to R'' in order to reduce the potential of the terminal c to a voltage corresponding to the switching point remaining voltage 7, that is, 1/5 V, then the midpoint of the resistors 202 and 202 is Voltage V _1- ' is 6/35V (voltage corresponding to remaining liquid level 6), resistor 202, 20
The voltage V _2- ' at the midpoint of 3 is 5/35V (voltage equivalent to 5), the voltage V _3- ' at the midpoint of resistors 203 and 204 is 4/35V (voltage equivalent to 4), The voltage at the midpoint of resistors 204 and 205, V _4- ', is 3/35V (voltage equivalent to 3), and the voltage at the midpoint of resistors 205 and 206.
V _5- ′ drops to 2/35V (voltage equivalent to 2), and voltage V _6- ′ at the midpoint of resistors 206 and 207 drops to 1/35V (voltage equivalent to 1), respectively. This becomes a new reference voltage for comparison elements 211-216.

Therefore, when the remaining liquid level is 7 to 6, V ₊ ′ is
Since the output voltage becomes higher than V _1- ′ to V _6- ′, the output voltage of the comparison elements 211 to 215, which had been at a low level, returns to a high level again, and the display segments 401 to 401, which were in a non-display state, 405 returns to the display state, and thus display segments 401 to 406 become display states.

When the remaining liquid level is 6 to 5, V ₊ ′ is larger than V _2- ′ to V _6- ′ but smaller than V _1- ′, so only the output voltage of comparison element 211 becomes low level, and the display segment The display segments 402 to 406 remain in the display state, and the display segment 401 goes into the non-display state.

When the remaining amount of liquid is 5 to 4, V ₊ ′ is larger than V _3- ′ to V _6- ′, but smaller than V _1- ′ and V _2- ′, so comparison elements 211 and 212 The output voltage becomes low level, display segments 403 to 406 are in a display state, and display segments 401 and 402 are in a non-display state.

When the remaining liquid amount is 4 to 3, V ₊ ′ is larger than V _4- ′ to V _6- ′, but smaller than V _1- ′ to _{V 3-} ′, so comparison elements 211 to 213 The output voltage becomes low level, display segments 404 to 406 are in a display state, and display segments 401 to 403 are in a non-display state.

When the remaining amount of liquid is 3 to 2, V ₊ ′ is larger than V _5- ′ and V ⁶ _- ′, but smaller than V _1- ′ and V _4- ′, so comparison elements 211 to 214 The output voltage becomes low level, display segments 405 and 406 are in a display state, and display segments 401 to 404 are in a non-display state.

When the remaining amount of liquid is 2 to 1, V ₊ ′ is larger than V _6- ′ and smaller than V _1- ′ to _{V 5-} ′, so the output voltages of comparison elements 211 to 215 become low level,
Only display segment 406 is in a display state, and display segments 401 to 405 are in a non-display state.

When the remaining amount of liquid is 1 or less, V ₊ ′ is smaller than V _1- ′ to V _6- ′, so the output voltages of the comparison elements 211 to 216 become low level, and the display segment 40
1 to 406 are all in a non-display state.

In addition, if the remaining liquid level is the switching point remaining level, 7
When the amount is higher, the transistor 601 is on and the transistor 602 is off, display segments 611 to 617 display F and display segments 618 to 624 display E, and this display indicates that the remaining liquid level has decreased to 7 or less. It does not switch until When the amount of liquid consumed increases and the remaining liquid level becomes 7 or less, the transistor 601 is turned off, the transistor 602 is turned on, and the display segment 61 is turned off.
1 to 617 are 7, display segments 618 to 624
0 is switched and displayed respectively.

Furthermore, if the remaining liquid level is the switching point remaining level, 7
When the liquid level decreases to below, the transistor 302 is turned off and the display segment 501 becomes a display state, and the remaining amount of liquid decreases, and the display scale section 4
In addition to displaying an enlarged display of an area with a small amount of liquid remaining, a warning message indicating a lack of remaining liquid is displayed.

In addition, FIG. 2A shows that the remaining amount of liquid is 30 to 25, and FIG. 2B shows that the remaining amount of liquid is 3 to 2.

[Application examples of the invention]

In the above embodiment, the comparison section 2 and the switching section 3 convert the output voltage of the detection section 1 into a digital quantity using an A/D converter or the like, calculate this digital quantity, convert it into display data, and display the data on the display scale section. 4, the display symbol section 6, etc., may be a calculation means constituted by, for example, a microcomputer.
It may also be configured with a changeover switch (as disclosed in Publication No. 39451), and the changeover switch may be operated to artificially enlarge and display the remaining amount of liquid when the remaining amount of liquid is desired. , the display symbol section 6 switches between displaying F and 7 in the display segments 611 to 617 and F and 0 in the display segments 618 to 624, but there are two sets of display symbols that display the status of the display area, e.g. , one set of display symbols may display F and E, and the other set may display 7 and 0, and one of these two sets of display symbols may be selectively displayed.

Incidentally, even if the range switching display section 5 is not particularly provided, there is no effect on display reading.

Further, the number of display segments on the display scale section 4 and the display symbols of the display segments on the display symbol section 6 are not limited to the above embodiments, and can be arbitrarily changed according to the capacity of the liquid tank and the remaining amount of the switching point. Needless to say.

〔Effect of the invention〕

The present invention includes a detection unit that outputs a voltage according to the amount of liquid remaining in a liquid tank, and a plurality of display segments arranged in a line based on the voltage from the detection unit, the display segment being in a display state and the display segment being in a non-display state. a bar graph type display scale section that is divided into display segments to display the remaining amount of liquid and consumption amount; and a bar graph display scale section that is arranged near the display scale section and shows the state of the display area of the display scale section. a display symbol portion; and a switching portion that switches the display segment of the display scale portion from the non-display state to a display state to enlarge and display the region with a low amount of liquid, and also switches the display symbol portion to scale down the display segment; Because of this structure, it is possible to display in detail the most important area with a small amount of liquid remaining, and in particular, it is possible to increase the accuracy of the display without increasing the number of display segments on the display scale. Since the display symbol section is also switched and scaled down at the same time as the display scale section is switched, misunderstandings will not occur when reading the display scale section.

This can be expected to have a great effect on improving the safety of vehicles, especially when used in fluid gauges that display the remaining amount of fuel in vehicles such as automobiles.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a liquid meter according to an embodiment of the present invention, and FIG. 2 is a display example of the liquid meter shown in FIG. 1...Detection section, 2...Comparison section, 3...Switching section,
4...display scale part, 401-406...display segment, 6...display symbol part.

Claims (1)

[Claims] 1. A detection section that outputs a voltage according to the remaining amount of liquid in the liquid tank, and a plurality of display segments arranged in a line based on the voltage from this detection section, including a display segment in a display state and a display segment in a non-display state. a bar graph type display scale section that is divided into two parts to display the remaining amount and consumption amount of the liquid;
A display symbol section disposed near the display scale section and indicating the state of the display area of the display scale section; and a display symbol section that is arranged near the display scale section and indicates the state of the display area of the display scale section; A liquid level meter comprising: a switching section that enlarges and displays the symbol, and switches the display symbol section to scale down the display symbol section.