JPH06288965A - Oxygen concentration measuring instrument - Google Patents

Abstract

PURPOSE:To enable an oxygen concentration measuring instrument to stably operate for a long period in a low-humidity, high-temperature environment and, at the same time, to increase the degree of freedom in design of an electric device for fitting an oxygen concentration measuring instrument by positioning either one of a negative and positive electrodes along the internal surface of an electrolyte container. CONSTITUTION:When the title measuring instrument is installed in a low-humidity, high-temperature environment, for example, in an outdoor SF6-gas enclosed electric device, an electrolyte 4 evaporates through an FEP membrane 8 and bubbles in an AB-made container 11 grow. As a result, an expanded gas phase 13 interrupts measurement. When, however, a negative electrode 12 is formed on the internal surface of the container 11 so as to surround the electrolyte 4 in the container 11, normal and stable measurement can be performed, since the electrolyte 4 exists between the negative electrode 12 and a positive electrode 13 for a long period. Since such an effect can be obtained irrespective of the type of the container 11, whether a vertical type (the positive electrode 3 is on the down side) or horizontal type (the electrode 3 is on the lateral side), the degree of freedom of electric device for fitting the measuring instrument can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a galvanic battery type oxygen concentration measuring instrument, which is equipped with a negative electrode, a positive electrode, an electrolytic solution and an electrolytic solution container, and applies a chemical reaction which produces an amount of electrons corresponding to the oxygen concentration in the atmosphere. It is about.

[0002]

2. Description of the Related Art FIG.
It is a sectional side view of the conventional oxygen concentration measuring instrument shown on page 619 of 7.60.1992. In FIG, 1 ₁ to 1 ₃ is composed of three parts be made of ABS container covering the whole. Reference numerals 2 and 3 denote a negative electrode and a positive electrode forming a galvanic battery, 3a denotes a lead wire connected to the positive electrode 3, and 4 denotes an electrolyte solution filled in the ABS container 1 ₁ . The negative electrode 2 is arranged in the electrolytic solution 4 and has a rod-like shape.

When the oxygen concentration measuring device is turned upside down, the air bubble 6 in the electrolytic solution 4 moves to the positive electrode 3 and the negative electrode 2 moves.
And a separator that prevents the electrolytic solution 4 between the positive electrode 3 and the positive electrode 3 from being blocked. The bubbles 6 are put in the electrolytic solution 4 to absorb the volume change of the electrolytic solution 4 due to the temperature change, and the size of the bubbles 6 grows as described later. 7 is a thermistor that corrects the output voltage of the oxygen concentration measuring device when the ambient temperature changes, 8 and 9 are FEP diaphragms and porous PTFE plates in which oxygen contained in the atmosphere diffuses, and 10 is AB.
O-ring for maintaining airtightness between S containers 1 ₁ and 1 ₃ , 1
Reference numeral 1 is a resistance for converting the output of the oxygen concentration measuring device into a voltage.

Next, the operation of the above conventional oxygen concentration measuring instrument will be described. When the oxygen concentration measuring device is placed in the atmosphere to be inspected, oxygen contained in the atmosphere diffuses in the porous PTFE plate 9 and the FEP diaphragm 8 and then dissolves in the electrolytic solution 4. When the electrolytic solution 4 is an acidic electrolytic solution such as acetic acid-potassium acetate-lead acetate aqueous solution, the following chemical reaction occurs. In the positive electrode 3: O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O In the negative electrode 2: 2Pb + 2H ₂ O → 2PbO + 4H ⁺ +4
e ⁻ Total reaction: O ₂ + 2Pb → 2PbO The positive electrode 3 is made of carbon (C) and the negative electrode 2 is made of lead (Pb).

Since the amount of oxygen in the atmosphere dissolved in the electrolytic solution 4 is determined by the oxygen concentration and the FEP diaphragm 8, the rate of the above reaction is determined by the oxygen concentration when the thickness of the FEP diaphragm 8 is constant. Will be. Therefore,
Since an amount of electrons corresponding to the oxygen concentration is generated in the negative electrode 2, a voltage output can be obtained by passing a current due to the electrons through the resistor 11, and the oxygen concentration in the atmosphere can be detected from this output voltage.

The oxygen concentration measuring device is used, for example, as a gas leak detecting device by being installed in an electric device filled with SF ₆ gas. FIG. 5 shows an example of such an electric device. In the figure, 101 is a sealed container,
102 is a movable electrode, 103 is a movable side terminal, 104 is a bushing, 105 is a fixed side electrode, 106 is a fixed side terminal, 1
Reference numeral 07 is a bushing, 108 is a drive shaft for driving the movable electrode 102, 109 is a drive lever connected to the drive shaft 108, 110 is a lock mechanism for locking the drive lever, 11
1 is SF ₆ gas filled in the sealed container 101, 112
Is a conventional oxygen concentration measuring device used in a gas leak detection device, and 113 is an alarm display device for displaying an alarm based on the output signal of the oxygen concentration measuring device 112.

[0007]

The oxygen concentration measuring device is used in an environment where the humidity is low and the temperature is high due to the effect of sunlight as in the case where the above electric device is installed outdoors. In this case, the electrolyte solution 4 may run out over time, and as a result, the bubbles 6 in the electrolyte solution 4 grow in a vapor phase. This is because when the humidity is low, the partial pressure of water vapor in the atmosphere becomes low, and when the temperature is high, diffusion becomes active, and AB
S-made container 1 ₁ of the electrolytic solution 4 from the vessel wall and FEP diaphragm 8 is due to evaporation. At this time, even to suppress the evaporation of the electrolyte solution 4 by transmission from ABS-made container 1 ₁ of the container wall FE
Evaporation from the P diaphragm 8 cannot be suppressed.

Therefore, when the conventional oxygen concentration measuring device is used in the above electric device, the rod-shaped negative electrode 2 is vibrated by vibration or the like.
There is a problem that the gas phase surrounds the area around and the electrolytic solution 4 between the negative electrode 2 and the positive electrode 3 is cut off, and the output voltage becomes unstable. Further, when the gas phase becomes large, the electrolytic solution 4 between the rod-shaped negative electrode 2 and the positive electrode 3 is blocked depending on the arrangement direction of the oxygen concentration measuring device, so that the arrangement direction of the oxygen concentration measuring device is limited, There is a problem that the degree of freedom in designing the electric device is reduced.

The present invention has been made in order to solve the above problems, and it operates stably for a long period of time even in an environment of low humidity and high temperature, and an electrical device to which this oxygen concentration measuring instrument is attached. It is an object of the present invention to obtain an oxygen concentration measuring instrument that can improve the degree of freedom in design.

[0010]

The oxygen concentration measuring device according to claim 1 of the present invention comprises a negative electrode, a positive electrode, an electrolytic solution and an electrolytic solution container filled with the electrolytic solution, and an amount corresponding to the oxygen concentration in the atmosphere. Is a galvanic battery type that applies a chemical reaction that produces electrons, and one of the negative electrode and the positive electrode is arranged along the inner wall surface of the electrolytic solution container.

In the oxygen concentration measuring device according to the second aspect of the present invention, a notch is formed on the inner wall surface of the electrolytic solution container from a position where it contacts the negative electrode to a position where it contacts the positive electrode, and the notch is made of the electrolytic solution. It is satisfied.

[0012]

In the oxygen concentration measuring device according to the first aspect of the present invention, the oxygen concentration measuring device is arranged along the inner wall surface of the electrolytic solution container even when the vapor phase in the electrolytic solution grows and its volume becomes large. Contact between the electrodes and the electrolyte is maintained. Therefore, even in such a case, the operation is normal and stable for a long period of time. In addition, the installation orientation is not limited.

In the oxygen concentration measuring device according to the second aspect of the present invention, the blocking of the electrolytic solution between the negative electrode and the positive electrode is prevented by the electrolytic solution in the cut portion. Therefore, it operates stably for a long period of time, and the orientation of installation is not limited.

[0014]

【Example】

Example 1. The first embodiment is an embodiment according to claim 1 of the present invention. First Embodiment FIG. 1 is a side sectional view of an oxygen concentration measuring instrument showing a first embodiment of the present invention. In the figure, the same or corresponding parts as those of the conventional oxygen concentration measuring device shown in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted. In the figure, 12 is made of ABS container 1 ₁ of the inner wall surface arranged cylindrical anode along as electrolyte container, 13 is a gas phase bubbles above has grown.

Next, the operation of the oxygen concentration measuring device according to the first embodiment will be described. In an environment of low humidity and high temperature, for example,
As described above, in the oxygen concentration measuring device placed inside the SF ₆ gas-filled electric device installed outdoors, as described above,
Electrolyte solution 4 in the oxygen concentration measuring device by evaporation of the electrolyte 4 via the diaphragm 8 gradually decreases, bubbles ABS-made container 1 ₁ is the volume of the gas phase 13 is expanded to grow. However, in the oxygen concentration measuring device of this embodiment 1, since the negative electrode 12 surrounds around the electrolytic solution 4 in the ABS-made container 1 ₁ is arranged, vertically positive electrode 3 becomes lower (in FIG. 1 direction)
In addition to the above, in the case of the horizontal orientation in which FIG. 1 is rotated by 90 °, the electrolytic solution 4 is placed between the negative electrode 12 and the positive electrode 3.
Is present, the oxygen concentration can be measured normally and stably.

In the conventional oxygen concentration measuring device shown in FIG. 4, the separator 5 prevents the bubbles 6 from coming into contact with the positive electrode 3, and the electrolytic solution 4 always exists between the negative electrode 2 and the positive electrode 3. It is devised to be. This separator 5
Is effective when the bubbles 6 grow slightly and are vertically placed, but when the bubbles 6 grow and are in a vapor phase or horizontally, the rod-shaped negative electrode 2 and the electrolytic solution 4 are used. Since the and are not in contact with each other, the blocking of the electrolytic solution 4 between the negative electrode 2 and the positive electrode 3 cannot be prevented.

[0017] However, in the oxygen concentration measuring device of this first embodiment, there by blocking prevention of the electrolyte solution 4, placing the negative electrode 12 irrespective to the separator along the inner wall surface of the ABS-made container 1 ₁ Therefore, normal and stable operation can be obtained. If a separator is present, SF that has entered from the outside through the FEP diaphragm 8
_{The 6} gas may stay near the positive electrode 3 and cover the positive electrode 3 to cause a decrease in the output voltage. However, since the oxygen concentration measuring instrument of Example 1 is not provided with a separator,
This will not happen.

Further, an adsorbent for removing impurities such as moisture is arranged in the SF ₆ gas space in the electric device, and even if the electrolytic solution 4 evaporates, it is quickly adsorbed by the adsorbent. Therefore, there is no risk of polluting the gas atmosphere. Although the negative electrode 12 has a cylindrical shape, it may have a cylindrical shape having an opening or a cage shape.

Example 2. The second embodiment is an embodiment according to claim 2 of the present invention. In Example 1, the negative electrode 1
The shape and arrangement of No. 2 makes it possible to operate normally and stably even in the presence of a gas phase or in the case of horizontal placement. In the second embodiment, as shown in FIG.
The normal and stable operation is obtained by providing it on the inner wall of the ABS container 1 ₁ which is in contact with. FIG. 3 shows III-III of FIG.
Is a sectional view taken along the line, the negative electrode 12a became a cage in FIG, 14 is cut portion formed from a position in contact with the anode 12a to the inner wall surface of the ABS-made container 1 ₁ to a position in contact with the positive electrode 3 Is. The notch 14 is filled with the electrolytic solution 4 inside, and serves to prevent the electrolytic solution 4 between the negative electrode 12 a and the positive electrode 3 from being interrupted. The operation of injecting the electrolytic solution 4 into the cut portion 14 is performed when the inside of the ABS container 1 ₁ is in a depressurized state during the assembly of the oxygen concentration measuring device. This is to prevent oxygen from adsorbing inside the cut portion 14.

The electrolytic solution 4 injected into the notch 14 does not easily come out from the notch 14 because of the surface tension. Even by evaporation of the electrolyte solution 4 is advanced gas phase grown ABS-made container 1 _1, no electrolytic solution 4 in the notch 14 is eliminated. Therefore, by providing about four cut portions 14 at equal intervals, it is possible to obtain a normal and stable output voltage even in a state of being placed laterally or reversely (a state where the positive electrode 3 is on the upper side). .

[0021]

Since the present invention is constructed as described above, it has the following effects.

According to the oxygen concentration measuring device of the first aspect of the present invention, since one of the negative electrode and the positive electrode is arranged along the inner wall surface of the electrolytic solution container, it is possible to operate in an environment of low humidity and high temperature. Also in this case, there is an effect that it can operate stably for a long period of time and the degree of freedom in designing an electric device to which the oxygen concentration measuring device is attached can be improved.

According to the oxygen concentration measuring device of the second aspect of the present invention, the notch is formed on the inner wall surface of the electrolytic solution container from the position where it contacts the negative electrode to the position where it contacts the positive electrode. Since it is filled with, it has the effect that it can operate stably for a long time even in an environment of low humidity and high temperature, and that it can improve the degree of freedom in designing the electric device to which this oxygen concentration measuring instrument is attached. .

[Brief description of drawings]

FIG. 1 is a side sectional view of an oxygen concentration measuring instrument according to a first embodiment of the present invention.

FIG. 2 is a side sectional view of an oxygen concentration measuring instrument showing Embodiment 2 of the present invention.

3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a side sectional view showing a conventional oxygen concentration measuring device.

FIG. 5 is an internal structural diagram of an SF ₆ gas filled electric device in which an oxygen concentration measuring device is used.

[Explanation of symbols]

1 ₁ to 1 ₃ ABS steel container (electrolyte container) 3 positive electrode 4 electrolyte 12,12a anode 14 notch

Claims (2)

[Claims] 1. A galvanic battery-type oxygen concentration measuring instrument comprising a negative electrode, a positive electrode, an electrolytic solution, and an electrolytic solution container filled with the electrolytic solution, and applying a chemical reaction that produces an amount of electrons corresponding to the oxygen concentration in the atmosphere. The oxygen concentration measuring device according to claim 1, wherein one of the negative electrode and the positive electrode is arranged along an inner wall surface of the electrolytic solution container. 2. A notched portion is formed on the inner wall surface of the electrolytic solution container from a position in contact with the negative electrode to a position in contact with the positive electrode, and the notched portion is filled with the electrolytic solution. Item 2. The oxygen concentration measuring device according to item 1.