JPH05296904A - Gas sensor - Google Patents

Abstract

PURPOSE:To provide a gas sensor which can measure the concentration of a gas, such as carbon dioxide contained in an always continuously flowing liquid like a carbonated spring even in the flowing state of the liquid. CONSTITUTION:The title sensor is provided with a liquid current tube 3 which is provided with a liquid inlet 1 and liquid outlet 2 and has a rectangular cross section, cylinder 5 formed on the upper wall 4 of the tube 3 between the inlet 1 and outlet 3, air vent 6 formed through the cylinder 5, air passage 8 which is formed on the internal surface of the cylinder 5 and communicated with the side face and bottom surface of a piston 7, and blocking surface 10 which is formed below the opening 9 of the passage 8 and blocks the vent 6. In addition, valves 11 which respectively block the inlet q and outlet 2 when the surface 10 blocks the vent 6, airtight cell 12 formed of the valves 11 and piston 7, ultrasonic vibrator 14 incorporated in the tube 3 constituting the cell 12, and pressure sensor 15 which is provided above the vibrator 14 and faced to the vibrator 14 in the cell 14 are also provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas sensor for detecting the concentration of a gas dissolved in a liquid, for example, in a cell that fluctuates when carbon dioxide gas dissolved in water is released into a cell having airtightness. The present invention relates to a gas sensor that detects the concentration of gas in a liquid from the pressure of, and is applicable to, for example, a sensor that detects the concentration of carbon dioxide gas in a carbonated spring or the like.

[0002]

2. Description of the Related Art For example, as a carbon dioxide sensor for detecting the concentration of carbon dioxide in a liquid, one which adds a chemical to the liquid phase to adjust the pH of the liquid phase and electrochemically detects the concentration of carbon dioxide, Chemicals are added to the liquid phase to release dissolved carbon dioxide, and the concentration of carbon dioxide is detected from the heat conduction of the gas phase from which carbon dioxide was released. The concentration of carbon dioxide is determined by infrared absorption of the liquid phase. What is detected is known.

However, the gas sensor as described above has a problem that its operation is very complicated and it takes a lot of time and labor for its use. For example, it is not practical to detect the concentration of carbon dioxide gas in a carbonated spring. ..

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to simplify a gas concentration such as carbon dioxide in a liquid such as a carbonated spring that is constantly flowing even in a system in which the liquid is flowing. Moreover, it is a point to provide a gas sensor capable of instantaneous measurement.

[0005]

A gas sensor for detecting a gas concentration in a liquid according to the present invention comprises: (1) a liquid flow pipe 3 having a liquid inlet 1 and a liquid outlet 2 on the left and right, and (2) An upward cylindrical cylinder 5, (3) formed between the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 and formed on the upper wall 4 of the liquid flow pipe 3 and communicating with the liquid flow pipe 3. The cylinder cylinder 5 has a vent hole 6 communicating with the outside air, (4) a piston 7 which is vertically moved while sliding on the inner surface of the cylinder cylinder 5, and (5) a vent communicating with the side surface and the bottom surface of the piston 7. Road 8,
(6) A closed surface 10 for closing the vent hole 6, which is formed below the opening 9 in which the vent passage 8 opens to the side surface, and (7) the liquid flow pipe when the closed surface 10 closes the vent hole 6. 3 is a valve 11 for closing the liquid inlet 1 and the liquid outlet 2 of (3), (8) a valve 11 for closing the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3, the liquid flow pipe 3, and the piston 7 Cell 12 having (9)
An ultrasonic transducer 14 mounted inside the lower wall 13 of the liquid flow tube 3 which constitutes the cell 12, and (10) inside the cell 12 and which is provided above the ultrasonic transducer 14 and oppositely. It is characterized in that a pressure sensor 15 is provided.

[0006]

A gas sensor for detecting the concentration of a gas flowing in a liquid according to the present invention comprises a liquid flow pipe 3 having a rectangular cross section having a liquid inlet 1 and a liquid outlet 2 on the left and right. Between the outlets 2, an upward cylindrical cylinder 5 is formed on the upper wall 4 of the liquid flow pipe 3, and a piston 5 for vertically moving up and down is attached to the cylindrical cylinder 5 to form the liquid flow pipe 3 A valve 11 for stopping the liquid flowing in the liquid flow pipe 3 is provided for collecting the liquid for detecting the gas concentration and the state in which the liquid constantly flows.
Then, the piston 5 that moves up and down in the vertical direction is
1 and the liquid flow tube 3 form a cell 17 having airtightness.
As a result, two phases of liquid phase are formed below the gas phase in the cell 17. An ultrasonic transducer 13 which is provided opposite to the pressure sensor 14 in the cell 11 and which is controlled by turning the current ON and OFF.
The gas dissolved in the liquid phase is released into the gas phase by the operation of, and the pressure in the gas phase rises.
To detect.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings related to the embodiments.

As shown in FIGS. 1 to 3, the gas sensor of the present invention comprises a liquid flow pipe 3 having a liquid inlet 1 and a liquid outlet 2 on the left and right sides and having a rectangular cross section. Liquid inlet 1 and liquid outlet 2 of this liquid flow pipe 3
An upward cylindrical cylinder 5 that communicates with the liquid flow pipe 3 is formed between the liquid flow pipe 3 and the upper wall 4 of the liquid flow pipe 3. The cross-sectional shape of this cylindrical cylinder 5 may be circular or rectangular and is not particularly limited. And this cylindrical cylinder 5
A ventilation hole 6 communicating with the outside is formed in the.

The gas sensor of the present invention further comprises a piston 7 that is driven up and down while sliding on the inner surface of the cylindrical cylinder 5.
Equipped with. The piston 7 is driven up and down by using a motor or a solenoid (not shown) as a drive source and turning the current on and off.
Can be controlled by. Further, the piston 7 is formed with an air passage 8 communicating with the side surface and the lower surface, and below the opening 9 opening on the side surface of the air passage 8,
It has a closing surface 10 for closing the vent hole 6. And
As shown in FIG. 1, valves 11, 11 for closing the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 at the same time that the closing surface 10 closes the vent hole 6 are attached to the liquid flow pipe 3. The valve 11 is composed of an electric valve 11a. Then,
A valve 11 for closing the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3, a piston 7 having a closed surface for closing the vent hole 6 of the cylindrical cylinder 5, and a cell 12 having airtightness with the liquid flow pipe 3 are provided. An ultrasonic transducer 14 is formed inside the lower wall 13 of the liquid flow tube 3 that constitutes the cell 12, and is further cylindrical inside the cell 12 and above the ultrasonic transducer 14. By attaching the pressure sensor 15 to the cylinder 5,
The pressure sensor 15 is provided above the ultrasonic transducer 14.

Now, with reference to FIGS. 1 to 3, the displacement of the position due to the elevation of the viston 7 and the driving of the ultrasonic transducer 13 will be described.

In FIG. 2, the valves 11 and 11 of the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 are both in an open state, and a gas such as carbon dioxide is dissolved in the liquid flow pipe 3, for example hot water. Indicates a flowing state. That is, the air passage 8 of the piston 7
Is the piston 7 at the position closed by the cylindrical cylinder 5.
Is lowered, and the ultrasonic transducer 14 is held in a stopped state.

FIG. 3 shows a state in which both the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 are closed, and the flow of hot water in the liquid flow pipe 3 is stopped. That is, the piston 7 moves up to a position where the air passage 8 of the piston 7 communicates with the air hole 6 of the cylindrical cylinder 5, and the outside air is introduced from the air hole 6 through the air passage 8 to the outside hot air on the hot water A. Gas phase B showing the same pressure
Is formed. Then, the ultrasonic transducer 13 is still held in a stopped state.

In FIG. 1, the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 are both closed, and the state in which the flow of the hot water in the liquid flow pipe 3 is stopped is maintained, and the piston 7 is Ascending further upward, the opening 9 of the ventilation passage 8 is closed by the cylindrical cylinder 5, and at the same time, the ventilation hole 6 is closed by the closing surface 10 to form the airtight cell 12 as described above. When the ultrasonic transducer 14 is turned ON for the first time at this stage, the gas dissolved in the hot water is released to the gas phase B of the cylindrical cylinder 5 forming the cell 12, the pressure rises, and the pressure sensor 15 causes the pressure fluctuation. The concentration of the gas is detected by detecting the fluctuation amount.

The above operation can be controlled by attaching an electric circuit for interlocking the drive of the piston 7, the valve 11, the pressure sensor 15 and the ultrasonic transducer 14 with each other.

4 to 6 show a gas sensor according to another embodiment. It is basically the same as the gas sensor described above.
Explaining the different points, the leg pieces 16 and 16 formed integrally with the viston 7 face each other, and the liquid passage holes 17 and 17 are formed in the leg pieces 16 to achieve the same function as that of the valve 11 of the embodiment. Fulfill That is, the leg pieces 16 and 16 are inserted into the long holes 18 and 18 extending in the front and rear of the lower wall 12 of the liquid flow pipe 3, and the valve 11 formed integrally with the piston 7 operates in conjunction with the lifting and lowering operation of the piston. .. That is, in FIG. 4, the valve 11
At the position where the liquid passage hole 17 of the leg piece 16 constituting the above is communicated with the liquid flow pipe 3, the valve 11 is in the open state, the hot water is flowing in the liquid flow pipe 3, and the ultrasonic vibration is generated. The child 14 is held in a stopped state.

In FIG. 5, the piston 7 is referred to as the piston 7
When the opening 9 of the ventilation passage 8 is raised to communicate with the ventilation hole 6 and is held at this position, the liquid flow pipe 3 is connected to the leg piece 1 of the valve 11.
At the same time, the outside air is introduced from the ventilation hole 6 through the ventilation path 8 while being blocked by 6, and water is retained between the leg pieces 16 and 16, and a vapor phase B having the same pressure as the outside air is formed on the hot water. Then, the ultrasonic transducer 14 is still held in a stopped state.

In FIG. 6, the piston 7 is lifted up to close the ventilation hole 6 of the cylindrical cylinder 5 until the closing surface 10 is closed,
When held in this position, the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3
Both shift to the closed state, and while maintaining the state in which the flow of the hot water A in the liquid flow pipe 3 is stopped, the cell 11 having airtightness is formed as described above. When the ultrasonic transducer 14 is turned on for the first time at this stage, the gas dissolved in the hot water B is released to the vapor phase A of the cylindrical cylinder 5 forming the cell 11, the pressure of the vapor phase A rises, and the cell 11 is turned on. The pressure sensor 15 attached to the lower surface of the constituent piston 7 detects the pressure variation, and the gas concentration is detected by the variation.

The above operation is performed by the piston 7 and the pressure sensor 1.
5 and the ultrasonic transducer 14 can be controlled by attaching an electric circuit interlocking with each other, so that the valve 11 can be controlled by controlling the piston 7 as compared with the gas sensor according to the above-described embodiment. The configuration is simple.

[0019]

According to the gas sensor of the present invention, a gas concentration such as carbon dioxide in a liquid such as a carbonated spring which is constantly and continuously flowing can be easily obtained from the pressure fluctuation even in the system in which the liquid is flowing. It can be detected in a short time, and therefore, the gas type to be detected can be used without limitation.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a gas sensor according to an embodiment of the present invention, showing a state in which a gas concentration in a liquid is detected from a state in which a liquid in which a gas dissolves is sampled.

FIG. 2 is a cross-sectional view of a gas sensor according to an embodiment of the present invention, showing a state in which liquid flows in a steady state.

FIG. 3 is a cross-sectional view of the gas sensor according to the embodiment of the present invention, showing a state in which the state is changed to a state of collecting a liquid.

FIG. 4 is a cross-sectional view of the gas sensor according to the embodiment of the present invention, showing a state in which the gas concentration in the liquid is detected from the state in which the liquid in which the gas is dissolved is sampled.

FIG. 5 is a cross-sectional view of a gas sensor according to an embodiment of the present invention, showing a state in which liquid is flowing in a steady state.

FIG. 6 is a cross-sectional view of the gas sensor according to the embodiment of the present invention, showing a state in which the state is changed to a state of collecting a liquid.

[Explanation of symbols]

 1 Liquid Inlet 2 Liquid Outlet 3 Liquid Flow Pipe 4 Upper Wall 5 Cylindrical Cylinder 6 Vent Hole 7 Piston 8 Vent Path 9 Opening 10 Closing Surface 11 Valve 12 Cell 13 Lower Wall 14 Ultrasonic Transducer 15 Pressure Sensor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichi Morii 1048, Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Works Co., Ltd. (72) Kenyuki Doi, 1048, Kadoma, Kadoma, Osaka Prefecture 72) Inventor Shin Tsugi Shin 1048 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works Co., Ltd.

Claims (1)

[Claims] 1. A liquid flow pipe 3 having a rectangular cross section having a liquid inlet 1 and a liquid outlet 2 on the left and right, and (2) between the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3, and An upward cylindrical cylinder 5 formed on the upper wall 4 of the liquid flow pipe 3 and communicating with the liquid flow pipe 3, (3) A ventilation hole 6 communicating with the outside air to the cylindrical cylinder 5, (4) A piston 7, which is driven to move up and down while sliding on the inner surface of the cylindrical cylinder 5, (5) an air passage 8 communicating between the side surface and the lower surface of the piston 7, (6) below an opening 9 in which the air passage 8 opens to the side surface. (7) When the closing surface 10 closes the vent hole 6, the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3 are formed.
A valve 11 for closing the valve, (8) a valve 11 for closing the liquid inlet 1 and the liquid outlet 2 of the liquid flow pipe 3, a liquid flow pipe 3, and an airtight cell 12 formed by the piston 7, (9) the cell Ultrasonic transducer 14 which is attached to the inside of the lower wall 13 of the liquid flow tube 3 which constitutes 12, and (10) pressure inside the cell 12 which is provided above the ultrasonic transducer 14 A gas sensor for detecting a gas concentration in a liquid, comprising a sensor 15.