JPH0692911B2 - Liquid amount detector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid amount detecting device capable of visually recognizing a liquid amount of petroleum or the like contained in a tank or the like at a position apart from the tank.

[0002]

2. Description of the Related Art The amount of oil such as petroleum contained in a tank is
As a device that can be visually recognized at a position apart from the tank, a device in which a float, a plurality of relays, and a meter such as an ammeter are combined is known. That is, the position of the float changes according to the liquid amount, the relays that operate differ depending on the position of the float, and the relays that operate
The swing range of the meter is different.

[0003]

In the above-mentioned conventional device, the relays constituting the device are expensive, and when a large number of relays are used, there is a problem that the price of the entire device increases, and the device becomes large. There is a problem. Also, the liquid to be detected may attack the relay contacts,
As a result, the relay malfunctions, and the reliability of the detected value decreases.

To solve this problem, a liquid amount detecting device as shown in FIG. 13 can be considered. That is, the position of a magnet (not shown) changes according to the liquid amount, and the magnetic sensors S10, S20, and S30 are installed at predetermined intervals, and the magnetic sensor S1 is installed.
0, S20, S30 is connected to the power supply B at one end, and the other ends of the magnetic sensors S10, S20, S30 are connected at output terminals O10, O.
20, connect to O30. In addition, output terminals O10 and O2
The ammeters A1, A2, A3 are connected between 0, O30 and the power source B so that the position of the magnet can be visually confirmed by the ammeter.

When the magnets are located substantially in the intermediate region between the two magnetic sensors adjacent to each other, the sensitivity of the two magnetic sensors is increased in order to prevent the two magnetic sensors from detecting the magnets. Depending on whether the distance between the two magnetic sensors is narrowed or the magnetic force of the magnet is increased, the two magnetic sensors adjacent to each other detect the magnet at the same time in the intermediate region. However, if the two magnetic sensors are operated in the intermediate region as described above,
The two ammeters may operate at the same time, and it may be determined that the liquid amount detection device has failed. To prevent this, AND circuits AND1 and AND2 and inverters I1 and I2 are required, and there is a problem that the number of parts increases.

An object of the present invention is to provide a liquid amount detecting device which can visually check the amount of liquid contained in a container such as a tank at a position distant from the tank and can be constructed at a low cost. is there. Further, according to the present invention, it is not determined that the liquid amount detection device is out of order when the two magnetic sensors detect the magnets in the substantially intermediate region of the two magnetic sensors adjacent to each other. It is an object of the present invention to provide a liquid amount detection device that does not require an increase in the number of parts.

[0007]

SUMMARY OF THE INVENTION The present invention has a plurality of magnetic sensors for detecting the magnets, the position of which is changed according to the amount of liquid, and a power source. It is installed at a predetermined distance, has a common contact, a normally open contact, and a normally closed contact, and one terminal of the power source is connected to the common contact of the first magnetic sensor, and n (n is 2 or more positive). The common contact of the nth magnetic sensor is connected to the normally closed contact of the (n-1) th magnetic sensor, and each normally open contact of the magnetic sensor forms an output terminal of the liquid amount detection device and is adjacent to each other. When the magnet is located approximately in the middle of the two magnetic sensors,
Two magnetic sensors adjacent to each other detect the magnet at the same time.

[0008]

FIG. 2 is a vertical sectional view showing an embodiment of the present invention.

The bearing disc 10 is screwed into an inlet of a tank T or the like containing heavy oil, gasoline, etc., and guide rods 11a and 11b are fixed to the lower surface of the bearing disc 10 so as to hang down. Has been done. The float 12 is made of foamed synthetic resin or the like, and is provided with two round through holes and one square through hole, and the round through hole has a guide rod 11 therein.
a and 11b are loosely fitted, and the strip plate 13 is loosely fitted in the rectangular through hole. The strip 13 is twisted by about 180 degrees. The upper end of the band plate 13 is connected to the lower end of the rotary shaft 20 which is inserted through the central portion of the bearing disc 10, and the lowermost end of the band plate 13 is rotatably supported by a bearing 14. The bearing 14 has a guide rod 11a. , 11b are installed on the bar 15 fixed to the lower part.

The upper part of the rotary shaft 20 is fixed to the center of the lower part of the scale 21, and the permanent magnet M is fixed to the upper surface of the scale 21. The graduation plate 21 has a substantially disk shape, and a taper portion is provided on an upper portion of the peripheral surface thereof, and the taper portion is graduated. The transparent cover 22 is a waterproof cover that covers the scale plate 21, the lower part of which is engaged with the bearing plate 10, and the wiring board 30 is fixed to the upper part thereof.

FIG. 1 shows a bearing disc 10 in the above embodiment.
It is a perspective view which decomposes | disassembles and shows the part located in the upper part.

The transparent cover 22 is provided with a pointer 22a, and the wiring board 30 has a battery B of 1.5 V or the like, ammeters A1, A2 and A3, and reed switches S11 and S12.
S13 and resistors R1, R2, R3, R4, R5 are provided. The reed switches S11 to S13 are arranged at a position directly above the locus of the permanent magnet M (that is, a position where the position can be detected when the permanent magnet M moves), and moreover, the reed switches S11 to S13 are radially predetermined from the center of the rotary shaft 20. It is arranged at each angle. In order to know the amount of liquid at a place distant from the wiring board 30, the ammeters A1 to A3 should be used.
It should be installed away from zero. In this case, the wiring board 30
In order to effectively utilize the space of battery B, wiring board 30
Preferably away from.

Further, for example, the reed switches S11 and S
Focusing on No. 12, the permanent magnet M is provided in an almost intermediate region between the two.
Is set, the reed switches S11 and S12 are set to detect the magnet M at the same time, and the region in which the reed switches S11 and S12 detect the magnet M at the same time is referred to as an “overlap detection region”. . That is, for example, when the magnet M is arranged directly below the reed switch S11, only the reed switch S11 detects the magnet M,
When the magnet gradually rotates toward the reed switch S12, there is a region (duplication detection region) in which the reed switches S11 and S12 detect simultaneously. When the magnet passes through the duplication detection region, only the reed switch S12 has the magnet M. Will come to detect.

The same applies to the reed switches S12 and S13, that is, when the magnet M is located approximately in the intermediate region between two reed switches adjacent to each other,
There is an overlap detection area in which two reed switches adjacent to each other detect the magnet M at the same time. Instead of the reed switch, another magnetic sensor that detects magnetism may be provided.

FIG. 3 is a diagram showing an equivalent circuit of the above embodiment.

In this embodiment, a magnet M whose position changes according to the amount of liquid, a plurality of magnetic sensors S11 to S13, and a power source B are provided, and the magnetic sensors S11 to S13 are installed at predetermined angles. , Common contact, normally open contact NO and normally closed contact N
C, one terminal of the power supply B is connected to the common contact of the first magnetic sensor S11, and the common contact of the n (n is a positive integer of 2 or more) magnetic sensor is n-1. It is connected to the normally closed contact NC of the second magnetic sensor, and the normally open contacts NO of the magnetic sensor are output terminals O11, O12, O of the liquid amount detection device.
13 is formed, and when the magnet M is located substantially in the intermediate region (overlap detection region) of two magnetic sensors adjacent to each other,
Two magnetic sensors adjacent to each other detect the magnet M at the same time. Further, the magnetic sensors S11 to S1
Ammeters A1, A2, and A3 are provided between the normally open contacts NO of 3 and the other terminal of the power source B.

Specifically, the common contact, the normally open contact NO, and the normally closed contact NC of the reed switch S11 are respectively the power source B.
Of the + terminal, the output terminal O11 and the common contact of the reed switch S12, and the normally open contact N of the reed switch S12.
O and the normally closed contact NC are respectively connected to the output terminal O12 and the common contact of the reed switch S13, the normally open contact NO of the reed switch S13 is connected to the output terminal O13, and nothing is connected to the normally closed contact NC. Not not. Further, the-terminal of the power source B is connected to the output terminal O10, and the output terminal O1
Ammeters A1, A2, and A3 are connected between 1, O12, O13 and the output terminal O10, respectively.

Next, the operation of the above embodiment will be described.

When the amount of the liquid L in the tank T changes, the height of the float 12 changes according to the height of the liquid surface, so that the strip plate 13 rotates by a predetermined angle according to the height. The rotary shaft 20 and the scale plate 21 rotate in conjunction with the band plate 13. The remaining amount of the liquid L in the tank T is displayed on the graduation plate 21, and the remaining amount of the liquid L in the tank T can be visually recognized by reading the scale corresponding to the pointer 22a provided on the transparent cover 22.

When the float 12 moves up and down to rotate the dial 21, the angular position of the magnet M changes. The position of the magnet M is set to the reed switches S11 to S11.
S13 detects and only the detected reed switch operates, and the corresponding ammeters A1 to A3 operate and display in accordance with the operation of the reed switches S11 to S13. Note that FIG.
In FIG. 2, the reason why only the reed switch S12 is operating is that FIG. 2 shows an example in which the magnet M exists at a position where only the reed switch S12 detects the magnet M.

Then, the reed switches S11, S12,
The detection areas in which S13 detects the magnet M,
Then, there is an overlap detection area (an area in which is also shown in the figure) detected by both the reed switches S11 and S12. Reed switches S12 and S1
Similarly, for 3 and 3, there is an overlap detection region (a region in which and are also shown in the figure) between the reed switches adjacent to each other. In addition, the detection region shown below by a square broken line is a region in which none of the reed switches detects the magnet M, and indicates that the remaining amount of the liquid L is zero or close to zero. , Symbols F and E indicate full tank and zero residual quantity, respectively.

Specifically, when the liquid level of the liquid L is located near the upper end of the tank T, only the reed switch S13 operates, only the ammeter A3 operates, and the liquid level gradually decreases. , The reed switches S13 and S12 are operated together, only the reed switch S12 is operated, the reed switches S12 and S11 are operated together, only the reed switch S11 is operated, and the remaining amount of the liquid L becomes zero. The reed switch operation stops. When only the reed switch S12 operates, the ammeter A
When only 2 operates and only reed switch S11 operates, only ammeter A1 operates and reed switch S11 operates.
Since the reed switch S13 is de-energized when both 13 and S12 are operated, only the ammeter A2 is operated, and the reed switch S12 is de-energized when both the reed switches S12 and S11 are operated. Therefore, only the ammeter A1 operates. These states are shown in FIG.

By the way, for example, the reed switch S13.
When the magnet M is located in the overlap detection area (the area in which and are also shown in FIG. 3) that both S1 and S12 detect, the reed switches S13 and S12 operate simultaneously. The current is cut off, so only the ammeter A2 operates. That is, when the reed switch S13 detects the magnet M and then the reed switch S12 detects the magnet M, no discontinuous region in which neither of the reed switches detects the magnet M occurs in the boundary region, and 2 Even if the two reed switches detect the magnet M at the same time, no abnormality occurs in the detection result. Further, if the ammeters A1 to A3 are installed away from the tank T, the amount of the liquid contained in the container such as the tank T can be reliably visually confirmed at a position away from the tank, and no relay is used. Therefore, the liquid amount detection device can be constructed at low cost. Also, a single-pole double-throw switch (a switch having a common contact, a normally open contact, and a normally closed contact) is used as the reed switches S11 to S13, and the normally open contact of one reed switch is connected to the common contact of the adjacent reed switch. Therefore, when the two magnetic sensors detect the magnets in the substantially intermediate region between the two magnetic sensors adjacent to each other without using the logic circuit as shown in FIG. It is not determined that there is a failure, and in order to do so, it is not necessary to add a part such as the logic circuit shown in FIG.

FIG. 5 shows resistors 23, 22 instead of the ammeters A1 to A3 used in the embodiment shown in FIG.
21 and an ammeter A are provided. Then, one ends of the resistors R23, R22, R21 are connected to the normally open contacts NO of the magnetic sensors S23, 22, 21, respectively, and an ammeter is provided between the other ends of the resistors R23 to R21 and the negative terminal of the power source B. A is provided. The resistors R23, R22,
When the resistance values of R21 are r23, r22, and r21, respectively, r23 <r22 <r21.

In this embodiment, as the liquid L decreases, the reed switches S23, S22, S21 are operated in this order, and the resistors R23, R22, R21 are energized in this order, and the current is supplied to the ammeter A each time. Flowing. Moreover, r2
Since 3 <r22 <r21, the reed switch S2
As S3, S22, and S21 operate, the current flowing through the ammeter A decreases. This state is shown in FIG.

In the above embodiment, as the liquid L decreases, the reed switches S23, S22, S.
Although the operation is shown in the order of 21, the reed switches may be arranged in the opposite direction. In this way, as the liquid L increases, the reed switch S
It operates in the order of 21, S22, and S23. In this case, the ammeter A may display such that the remaining amount of the liquid L increases as the detected current value decreases. In order to obtain the same result as this, the twisting direction of the strip 13 may be reversed from that of the above-described embodiment, or r23 <r22 <r21 may be satisfied. When a voltmeter is used instead of the ammeter A (for example, in FIG. 5, when a predetermined resistance is connected instead of the ammeter A and a voltmeter is connected in parallel with this resistance),
In the voltmeter, as the detected voltage decreases,
It may be displayed so that the remaining amount of the liquid L increases. In the embodiment shown in FIG. 3, as the liquid L decreases,
Although the reed switches S13, S12, and S11 are shown to operate in this order, the same applies to the case where the reed switches are arranged in the opposite direction.

FIG. 7 shows that in the embodiment shown in FIG. 5, the resistor R2 is provided between the connection point between the resistors R21 and R22 and the ammeter A.
0 is provided, and the voltage / frequency converter C is connected in parallel with the resistor R20. The voltage / frequency converter C changes the frequency of the output signal according to the height of the input voltage. If the voltage / frequency converter C is provided, the measured liquid volume data can be transmitted to a remote place via a predetermined line such as a telephone line.

FIG. 8 is a circuit diagram showing another embodiment of the present invention, in which the reed switches S31 to S31 used therein.
The connection state between S33 and the power supply B is the same as the connection state between the reed switches S11 to S13 and the power supply B shown in FIG. And the normally open contact NO of the first magnetic sensor S31
A series circuit of a resistor R31 and an ammeter A is provided between the negative terminal of the power source B and the negative terminal of the power source B, and the normally open contact N of the nth magnetic sensor is provided.
A resistor is connected between O and the normally open contact NO of the (n-1) th magnetic sensor. That is, the second magnetic sensor S3
A resistor R32 is connected between the second normally open contact NO and the normally open contact NO of the first magnetic sensor S31, and the normally open contact NO of the third magnetic sensor S33 and the second magnetic sensor S32 are connected.
A resistor R33 is connected between the contact and the normally open contact NO.

In this embodiment, as the liquid L decreases, the reed switches S33, S32 and S31 operate in this order, and the resistors R33 + R22 + R21 and R22 + R2 are operated.
The current is applied in the order of 1 and R21, and the current flows through the ammeter A each time. If the resistance values of the resistors R33, R22, and R21 are r33, r32, and r31, then r31 = r32 = r.
33, the reed switches S33, S32,
As S31 operates, the current flowing through the ammeter A is
It decreases at a ratio of 1/3, 1/2, and 1. This state is shown in Figure 9.
It is shown in.

FIG. 10 shows an example of the embodiment shown in FIG.
Voltage / frequency converters C1, C2, C3 corresponding to the reed switches S21, S22, S23 are provided so that signals of different frequencies are output according to the operation of the reed switches S21, S22, S23. The voltage / frequency converters C1, C2, C3 have their own power sources B31, B32, B33 (power sources B31, B32, B3).
3 voltage is different from each other), and diodes D1 and D are provided to prevent current from flowing to unnecessary portions.
2 and D3 are provided. Also in the case of this embodiment, the measured liquid volume data can be transmitted to a remote place through a predetermined line such as a telephone line.

FIG. 11 shows a voltage / frequency converter C4 connected in parallel with the resistor R31 in the embodiment shown in FIG. The voltage / frequency converter C4 changes the frequency of the output signal according to the magnitude of the input voltage. If the voltage / frequency converter C4 is provided, the measured liquid volume data can be transmitted to a remote place via a predetermined line such as a telephone line.

FIG. 12 is an explanatory view showing another embodiment of the present invention, FIG. 1 (1) is a front view thereof, and FIG.
Is a vertical sectional side view.

In the embodiment shown in FIGS. 1 to 11, the dial 21 is rotated according to the remaining amount of the liquid L, and the magnet M is rotated along with this rotation. In the embodiment shown in FIG. 12, the magnet M1 moves up and down as the remaining amount of the liquid L increases and decreases, and the reed switches S11 to S13 are provided at positions corresponding to the up and down movement of the magnet M1. Reed switches S11-S13, battery B, ammeter A1-
The connection state with A3 is the same as the state of the embodiment shown in FIG.

The wiring board 31 of the electric circuit for connecting the reed switches S11 to S13, the battery B and the ammeters A1 to A3 is fixed to the transparent cover 22a.
a is fixed to the upper lid of the tank T. Also, the magnet M
In addition to the vertical movement, the linear movement may reciprocate linearly, such as moving left and right.

In the above embodiment, three reed switches are used, but a plurality of reed switches other than three may be used.

In the embodiment shown in FIG. 1, the strip 1
3 is twisted by about 180 degrees, but this twist angle is
It is appropriately determined according to the number of reed switches and resistors provided on the wiring board 30 and the arrangement angle of these. In addition, the number of reed switches and resistors and their arrangement angles are determined according to the rotation angle (actual height when the float 12 moves up and down) where the rotary shaft 20 that interlocks with the strip 13 actually rotates. May be defined.

As means for changing the position of the permanent magnet M in accordance with the liquid amount, means other than the means shown in FIG. 1 may be used.

Further, a switch may be provided before and after the power source B. In this way, the switch is pushed only when the user wants to know the liquid amount, and the power source B is consumed very little. Therefore, the life of the power source B is extended.

In the above embodiment, the resistors R20 and R3 are used.
1. A voltage / frequency converter is provided in parallel with 1 or in series with resistors R21, R22, and R23. However, the voltage / frequency converter is provided at a part other than these parts, that is, a part where the voltage changes due to the operation of the magnetic sensor. A converter may be provided.

[0040]

According to the present invention, the amount of liquid contained in a container such as a tank can be reliably visually recognized at a position distant from the tank and can be constructed at a low cost. When the two magnetic sensors both detect the magnets in the approximately middle region of the magnetic sensor, it is not determined that the liquid amount detection device has failed, and there is no need to increase the number of parts to do so. .

[Brief description of drawings]

FIG. 1 is an exploded perspective view of essential parts in an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing the above embodiment.

FIG. 3 is a diagram showing an electric circuit in the embodiment.

FIG. 4 is a diagram showing the relationship among the liquid amount, the operation of the reed switch, and the operation of the ammeter in the above-mentioned embodiment.

FIG. 5 is a circuit diagram showing another embodiment of the present invention.

FIG. 6 is a diagram showing the relationship among the liquid amount, the operation of the reed switch, and the operation of the ammeter in the embodiment shown in FIG.

FIG. 7 is a circuit diagram showing a modification of the embodiment shown in FIG.

FIG. 8 is a circuit diagram showing another embodiment of the present invention.

9 is a diagram showing the relationship among the liquid amount, the operation of the reed switch, and the operation of the ammeter in the embodiment shown in FIG.

FIG. 10 is a circuit diagram showing a modification of the embodiment shown in FIG.

FIG. 11 is a circuit diagram showing a modification of the embodiment shown in FIG.

FIG. 12 is a view showing another embodiment of the present invention, FIG. 1 (1) is a front view thereof, and FIG. 12 (2) is a longitudinal side view thereof.

FIG. 13 is a circuit diagram showing an example conceivable in the case where the liquid amount detection device is downsized without using a relay.

[Explanation of symbols]

10 ... Bearing board, 11a, 11b ... Guide rod, 12 ... Float, 13 ... Strip plate, 20 ... Rotating shaft, 21 ... Scale board, 22 ... Transparent cover, 30 ... Wiring board, S11-S13, S21-S23, S31 -S33 ... Reed switch, A, A1-A3 ... Ammeter, M ... Permanent magnet, C, C1-C3 ... Voltage / frequency converter, B ... Power supply.

Claims (5)

[Claims] 1. A liquid amount detection device having a magnet whose position changes according to the liquid amount, a plurality of magnetic sensors, and a power supply, wherein the magnetic sensors are installed at a predetermined angle or a predetermined distance, and a common contact is provided. And a normally open contact and a normally closed contact, one terminal of the power source is connected to a common contact of the first magnetic sensor, and the n-th (n is a positive integer of 2 or more) magnetic field. The common contact of the sensor is connected to the normally closed contact of the (n-1) th magnetic sensor, each of the normally open contacts of the magnetic sensor forms an output terminal of the liquid amount detection device, and the two magnetic sensors adjacent to each other. When the magnet is located in a substantially intermediate region of the two, the two magnetic sensors adjacent to each other detect the magnet at the same time. 2. The liquid amount detecting device according to claim 1, wherein an ammeter is provided between each normally open contact of the magnetic sensor and the other terminal of the power source. 3. The magnetic sensor according to claim 1, wherein one end of a resistor is connected to each of the normally open contacts of the magnetic sensor, and an ammeter is provided between the other end of the resistor and the other terminal of the power source. A liquid amount detection device characterized in that 4. The serial circuit of a resistance and an ammeter according to claim 1, wherein a series circuit of a resistance and an ammeter is provided between the normally open contact of the first magnetic sensor and the other terminal of the power source.
A liquid quantity detecting device, wherein a resistor is connected between the normally open contact of the n-th magnetic sensor and the normally-open contact of the (n-1) th magnetic sensor. 5. The voltage / frequency according to claim 1, wherein the frequency of the output signal changes in accordance with the height of the input voltage at the position where the voltage changes due to the operation of the magnetic sensor. A liquid amount detection device having a converter.