JP3590500B2 - Gas detector inspection device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a gas detector inspection device for calibrating a gas detector that detects leakage of various gases.
[0002]
[Prior art]
Today, city gas and the like are used in ordinary households, and various gases are used industrially. If these gases leak into the air, various harmful effects may occur.Therefore, it is necessary to search for leaks and take appropriate measures, and determine whether the gas concentration is below a preset reference value. A gas detector is used to make a determination. As such a gas detector, a so-called semiconductor gas detector is widely used. Gas detectors used in connection with the supply of city gas are legally required to be calibrated by specialists, for example, once a year. However, frequent accuracy checks are required to perform more reliable gas detection.
[0003]
The following method is used to calibrate the gas detector.
(1) A method of evaporating camphor gas organic solid (naphthalene) to make it a detection agent.
Such an organic solid substance directly sublimates from a solid to a gas so as to have a certain concentration in the atmosphere and is easily available, so that the gas detector can be easily calibrated.
(2) A method of using a detection gas at a predetermined concentration.
Dilute the gas to be detected to a predetermined concentration and store it in a large cylinder and take it out and use it for calibration of the gas detector. It is used by diluting it into a container such as a gas bag. (3) A method of diluting with a mixing device.
The gas and air are diluted by a dedicated mixing device to automatically bring the concentration to a predetermined concentration.
[0004]
[Problems to be solved by the invention]
Among the conventional methods for testing gas detectors, the method (1) of sublimating camphor gas organic solids as a detecting agent can be easily performed, but the concentration depends on the temperature. That is the problem. In addition, since the generated gas is generally different from the gas to be detected, the sensitivity characteristics of the gas detector are also different, so that highly reliable calibration cannot be performed. In the method of (2), where the detection gas is used at a predetermined concentration, even if it is stored in a large cylinder, if a part of the detection gas is taken out for calibration, air enters instead and the concentration in the cylinder changes. And the error increases. In the method of taking in a certain amount of gas with a syringe or the like and diluting each time calibration is performed, for example, in order to obtain a concentration of 150 ppm, a diluting operation of injecting 1.5 cc gas into a 10-liter container must be performed each time, which is troublesome. . Since the gas bag is made of a flexible synthetic resin film, long-term storage is impossible. Further, when it is necessary to calibrate a large number of gas detectors at the same time, for example, the diluting operation must be repeated many times, which is more troublesome.
[0005]
An object of the present invention is to provide a gas detector inspection device that can accurately calibrate a gas detector with a simple operation.
[0006]
[Means for Solving the Problems]
The present invention is a gas detector inspection device for applying a gas at atmospheric pressure at a predetermined reference concentration to a gas detector and performing calibration of the gas detector,
A high-pressure container for storing a gas having a reference concentration at a pressure higher than the atmospheric pressure,
A pressure regulator that adjusts the pressure in the high pressure gas to atmospheric pressure by reducing the pressure in multiple stages,
Provided on the output side of the pressure regulator, when a detection end of a predetermined shape of the gas detector is attached, the flow path is opened so as to guide gas from the output side of the pressure regulator to the gas detector, and the gas detector is removed. And a joint with an on-off valve for closing a flow path for guiding gas from the output side of the pressure regulator.
According to the present invention, since the gas of the reference concentration is stored in the high-pressure container at a pressure higher than the atmospheric pressure, the pressure is reduced to the atmospheric pressure by the pressure regulator, and the gas is guided from the joint with the on-off valve to the detection end of the gas detector. Thus, the gas detector can be calibrated. Since the pressure of the gas is reduced to the atmospheric pressure in a plurality of stages in the pressure regulator, the gas at the atmospheric pressure can be supplied for a long time even if the pressure in the high-pressure vessel fluctuates. The fitting with an open / close valve opens the flow path so that gas is guided from the output side of the pressure regulator to the gas detector when the detection end of the gas detector with the predetermined shape is attached, and the gas detector is removed when the gas detector is removed. Since the flow path for guiding gas from the output side of the pressure device is closed, the gas detector can be calibrated by one-touch simple operation.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
1 to 3 show a configuration of a gas detector inspection device 1 according to an embodiment of the present invention. 1 is a front view, FIG. 2 is a plan view, and FIG. 3 is a left side view. The gas cylinder 2 is filled with a detection gas of a high pressure, for example, 120 kgf / cm ² , for example, a natural gas called 13A at a reference concentration of 150 ppm. When the detection gas is used, the pressure in the gas cylinder 2 decreases. For example, when the pressure decreases to about 30 kgf / cm ^{2, the} support 3 is removed and the gas cylinder 2 is replaced. When the gas cylinder 2 newly filled with the detection gas is attached, the on-off valve 4 is opened, and the detection gas in the gas cylinder 2 is supplied to the governor 5. The governor 5 reduces the pressure of the high-pressure detection gas to, for example, 2 kgf / cm ² . A second stage governor 6 is connected to the secondary side of the governor 5, and a third stage governor 7 is connected to the second side of the second stage governor 6. In the second stage governor 6, the pressure of ² kgf / cm ² is reduced to 400 to 500 mmH ₂ O, and in the third stage governor 7, the pressure is further reduced to a pressure slightly higher than the atmospheric pressure.
[0008]
The detection gas reduced to a pressure slightly higher than the atmospheric pressure by the governors 5, 6, 7, which are three-stage pressure regulators, is led to the header 8. The header 8 has a partition 9 at the center, and the left and right are separated. An automatic on-off valve joint 10 is provided on the gas cylinder 2 side of the partition 9 so that the detection gas can be discharged only by inserting the detection end of the gas detector. When the detection end is removed, the detection gas flows out. Stopped automatically. That is, the detection gas is discharged only when the detection end of the gas detector is connected to the joint 10 with the automatic on-off valve with one hand, and if the inner volume of the gas cylinder 2 is 3.6 liters, the gas detector is about 90,000 times. Can be calibrated.
[0009]
A coupler 11 is provided on the right side of the header 8 partitioned by the partition 9 so that the detection gas filled in the gas cylinder 12 can be taken out. The gas cylinder 12, for example, carbon monoxide (CO) at a standard density of 400 ^ppm, filled at a pressure of ^{100kgf / cm 2 ~120kgf / cm 2} . The gas cylinder 12 is held by a support 13 and guided to the coupler 11 side of the header 8 via an on-off valve 14 provided at the top of the gas cylinder 12 and three-stage governors 15, 16 and 17.
[0010]
The inspection device 1 is housed in the housing 20 as a whole. In the housing 20, different types of gas cylinders 2, 12 are arranged at an interval from each other and fixed by supports 3, 13, respectively. When such an inspection apparatus 1 is used, two operators can simultaneously calibrate two types of detection gases. In addition to carbon monoxide, the other gas cylinder 12 may be filled with a refrigerant gas such as R-22 for inspection of refrigeration equipment, or LPG or the like as a combustible gas. It can also be used for calibration of a gas detector for exhaust gas of an automobile engine. Further, if both gas cylinders 2 and 12 are filled with 13A and the coupler 11 is replaced with the same one as the joint 10 with the automatic on-off valve, calibration can be performed simultaneously on the two gas detectors.
[0011]
FIG. 4 shows an operation of calibrating the gas detector using the inspection device 1 of FIG. The operation is started from step a1, and zero adjustment of the gas detector is performed in step a2. In step a3, the detection end of the gas detector is inserted into the joint 10 with an automatic on-off valve and connected. At step a4, the detection output of the gas detector is confirmed. The gas detector is provided with, for example, a meter and the like, and can detect a detection output by a swing of a needle. If the detection output does not reach the predetermined range, the adjustment is further performed in step a5, and the shake is confirmed again in step a4. When it is confirmed that the run-out has reached the predetermined range, the detection end of the gas detector is detached from the joint 10 with the automatic on-off valve in step a6, and the calibration operation of one gas detector is ended in step a7.
[0012]
FIG. 5 shows a cross-sectional configuration of the joint 10 with an automatic on-off valve shown in FIGS. A generally cylindrical housing 20 accommodates a valve seat 21 that is axially displaceable and has a narrow cross section. The valve element 22 can be brought into contact with the valve seat 21, and in the state of being in contact with the valve element 21, the valve element 22 is sealed by an O-ring 23 attached to the valve element 22. The force for pressing the valve body 22 toward the valve seat 21 is generated by the spring 24. A slider 25 is provided to separate the valve body 22 from the valve seat 21 against the pressing force of the spring 24 to open the valve. The slider 25 has a cylindrical shape and is provided with a vent hole 25a. The slider 25 is slidable inside the valve seat 21 in the axial direction. A ball 26 is mounted on the outlet side of the valve seat 21 opposite to the side on which the valve body 22 is seated. The outlet side of the valve seat 21 is lightly pressed against the valve body 22 by a sleeve 27 provided outside the housing 20. The force urging the sleeve 27 is provided by a spring 28. An O-ring 29 is also held inside the valve seat 21.
[0013]
The detection end 30 of the gas detector shown in FIG. 6 can be mounted on the outlet side of the valve seat 21 of the joint 10 with an automatic opening and closing valve. A step 31 is provided at the tip of the detection end 30, and when the detection end 30 is inserted into the outlet side of the valve seat 21 shown in FIG. 5, the step 31 is held at the position of the ball 26. When the detection end 30 is removed, the sleeve 27 is pushed in, the valve seat 21 is moved to the valve body 22 side, and the ball 26 is moved over the stepped portion 31 to the distal end side. The end 30 can be easily pulled out.
[0014]
FIG. 7 shows a schematic configuration of an inspection apparatus 41 according to another embodiment of the present invention. In the present embodiment, the gas cylinder 42 is held on the bottom surface of the frame 43 in a state of lying horizontally. The detection gas is guided to the header 48 from the on-off valve 44 provided at the top of the gas cylinder 42 and the three-stage governor 45, 46, 47. In the three-stage governors 45, 46, and 47, the pressure of the detection gas is reduced, for example, from 100 kgf / cm ² to a set pressure of 50 mmH ₂ O. The header 48 is provided with three joints 50a, 50b, and 50c with automatic on-off valves so that calibration can be simultaneously performed on a plurality of, for example, three gas detectors 49a, 49b, and 49c. The configuration of the joints 50a, 50b, 50c with an automatic opening and closing valve is the same as that of the joint 10 with an automatic opening and closing valve shown in FIG. The pressure of the detection gas in the header 48 can be confirmed by a water column gauge 51.
[0015]
【The invention's effect】
As described above, according to the present invention, a gas having a reference concentration is stored in a high-pressure vessel at a high pressure, reduced in pressure to atmospheric pressure by a multistage pressure regulator, and a joint with an on-off valve has a predetermined shape of a gas detector. The gas detector can be calibrated simply by attaching the detection end. The gas dilution operation is unnecessary, and if a gas having a reference concentration is stored in a high-pressure container in a high-pressure state, highly reliable calibration of the gas detector can be performed over a long period of time.
[Brief description of the drawings]
FIG. 1 is a front view of an embodiment of the present invention.
FIG. 2 is a plan view of FIG.
FIG. 3 is a left side view of FIG.
FIG. 4 is a flowchart showing an operation of calibrating a gas detector using the inspection device 1 of FIG.
FIG. 5 is a sectional view showing a schematic configuration of a joint 10 with an automatic on-off valve according to the embodiment of FIG. 1;
6 is a sectional view of a detection end 30 of a gas detector which can be combined with the joint 10 with an automatic opening / closing valve of FIG.
FIG. 7 is a perspective view showing a schematic configuration of another embodiment of the present invention.
[Explanation of symbols]
1,41 Inspection device 2,12,42 Gas cylinder 3,13 Supporting tool 4,14,44 On-off valve 15,16,17,45,46,47 Governor 8,48 Header 9 Partition 10,50a, 50b, 50c Automatic opening and closing Valve joint 11 Coupler 20 Housing 21 Valve seat 22 Valve element 25 Slider 26 Ball 27 Sleeve 30 Detection end 31 Step 43 Frame 49a, 49b, 49c Gas detector

Claims (1)

A gas detector inspection device for providing a gas of atmospheric pressure at a predetermined reference concentration to a gas detector and performing calibration of the gas detector,
A high-pressure container for storing a gas having a reference concentration at a pressure higher than the atmospheric pressure,
A pressure regulator that adjusts the pressure in the high pressure gas to atmospheric pressure by reducing the pressure in multiple stages,
Provided on the output side of the pressure regulator, when a detection end of a predetermined shape of the gas detector is attached, the flow path is opened so as to guide gas from the output side of the pressure regulator to the gas detector, and the gas detector is removed. A gas detector inspection device comprising: a pressure regulator; and a joint with an on-off valve for closing a flow path for guiding gas from an output side of the pressure regulator.

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