KR101913149B1 - Gas detector using internal-type standard gas for re-calibration - Google Patents

Gas detector using internal-type standard gas for re-calibration Download PDF

Info

Publication number
KR101913149B1
KR101913149B1 KR1020150168517A KR20150168517A KR101913149B1 KR 101913149 B1 KR101913149 B1 KR 101913149B1 KR 1020150168517 A KR1020150168517 A KR 1020150168517A KR 20150168517 A KR20150168517 A KR 20150168517A KR 101913149 B1 KR101913149 B1 KR 101913149B1
Authority
KR
South Korea
Prior art keywords
gas
sensor
standard
detector
connection pipe
Prior art date
Application number
KR1020150168517A
Other languages
Korean (ko)
Other versions
KR20170064047A (en
Inventor
이원배
Original Assignee
세주엔지니어링주식회사
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 세주엔지니어링주식회사 filed Critical 세주엔지니어링주식회사
Priority to KR1020150168517A priority Critical patent/KR101913149B1/en
Publication of KR20170064047A publication Critical patent/KR20170064047A/en
Application granted granted Critical
Publication of KR101913149B1 publication Critical patent/KR101913149B1/en

Links

Images

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/0004—Gaseous mixtures, e.g. polluted air
    • G01N33/0006—Calibrating gas analysers
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/02—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance
    • G01N27/04—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance
    • G01N27/12—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating impedance by investigating resistance of a solid body in dependence upon absorption of a fluid; of a solid body in dependence upon reaction with a fluid, for detecting components in the fluid
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/483—Physical analysis of biological material
    • G01N33/497—Physical analysis of biological material of gaseous biological material, e.g. breath
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/483—Physical analysis of biological material
    • G01N33/497—Physical analysis of biological material of gaseous biological material, e.g. breath
    • G01N33/4972—Determining alcohol content

Abstract

[0001] The present invention relates to a gas detector with built-in rechargeable standard gas, and more particularly, to a gas detector having a built-in standard gas reservoir therein for automatic re- The gas detector is equipped with a standard gas detector with built-in standard gas, which allows the user to carry out the basicization in real time in a simple manner, without having to go to a separate calibration center or manufacturer. .

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a gas detector,

The present invention relates to a gas detector having a built-in standard gas reservoir for allowing a reservoir of a standard gas used for re-initializing a gas detector to be mounted therein, so that it can be automatically re- Gas detector.

As the industry has developed since the Industrial Revolution, air pollution by toxic gases (CO, H2S, SO2, NOx) has been highlighted, and the risk of gas explosion and gas poisoning has increased. In this context, a catalytic combustion-type sensor was first reported by Johnson in 1923, and various types of gas sensors were subsequently developed.

Among them, the semiconductor type gas sensor is a sintered body of metal oxide semiconductors such as SnO 2, ZnO, In 2 O 3 and the like, and the presence or concentration of a specific gas in the air is measured as resistance change. It was firstly disclosed by Seiyama and Taguch in 1962. These semiconductor type gas sensors have been commercialized by Figaro in Japan in 1968 and have been mainly used for gas leakage alarm and gas concentration measurement. During this process, the sensor has evolved to meet the various detection gases and applications through the improvement of its materials and application sensing instruments, and it has been commercialized and used in industrial, medical and real life fields. In particular, gas sensors have been commercialized in the form of gas alarms, portable gas leak detectors, and portable alcohol analyzers due to the expansion of the supply of LNG and LPG gases and the social problem of drunken driving.

A semiconductor is classified into an n-type semiconductor and a p-type semiconductor according to its electrical conduction mechanism. SnO2, which is the most typical sensitizer, belongs to an n-type semiconductor, and the number of cations (Sn) is quantitatively smaller than the number of anions (O), so that excess electrons are generated, which contributes to electric conductivity. These SnO2 tend to adsorb deficient oxygen species in the atmosphere and try to solve the imbalance in the ratio of positive / negative ion numbers. Electrons that act as electrical conduction in the semiconductor due to the electronegativity of the adsorbed oxygen species are adsorbed on the surface of the adsorbed oxygen It becomes a localized state (that is, a captured state). Thus, the electrical conductivity is lost at this time. If SnO2 in this state is exposed to a reducing gas (e.g., CO, NH3), adsorbed oxygen on the surface reacts with these gas species to cause a reaction as shown in Reaction Scheme 1 below to desorb the adsorbed oxygen on the surface. At this time, the trapped electrons around oxygen can be freed again to contribute to the electrical conductivity. Accordingly, the electrical conductivity of the semiconductor sensor changes according to the target gas to be detected, and the presence or concentration of the gas species can be known through the electrical conductivity. On the other hand, as a catalyst, SnO 2, which is a sensitizer, is added with materials such as Pt, Au and Ag to increase the sensitivity.

<Reaction Scheme 1>

2CO + O 2 ? 2CO 2

In the case of the conventional gas detector, the sensor material and the gas are chemically reacted according to the external environment such as temperature, humidity, and gas, and the reference value of the sensor is changed to increase the measurement error of the device.

 On the other hand, the electrochemical sensor is a sensor for measuring the voltage and current generated by the oxidation / reduction reaction of the gas to be measured. When the gas sensor is manufactured using the electrochemical sensor, there is a merit that it is possible to operate very stably when the individual deviation is small and the reproducibility is excellent. However, when the sensor is deteriorated over time, Therefore, there is a problem in that it should be re-standardized by a specialized agency.

Accordingly, the gas appliance to which the semiconductor type or the electric type chemical gas sensor in which the error occurs as time elapses is automatically re-basicized at regular intervals without requesting the specialized agency, or if necessary, There has been an urgent need to develop a technique that can improve the utilization of gas devices having high precision at all times.

1 is a graph showing the resistance change characteristics of a portable alcohol measuring instrument (alcohol measuring instrument) according to the alcohol concentration. The change of the resistance value of the sensor material according to the gas concentration of a general semiconductor gas sensor is plotted as a natural algebraic change, and FIG. 2 shows the straight line.

Referring to FIG. 2, when an alcohol gas of 80 PPM is injected into the sensor and the sensor resistance at this time is calibrated to 20 k ?, the gas sensor of the gas concentration to be measured The gas concentration can be grasped by substituting the output resistance value into the characteristic curve.

3 is a circuit diagram showing an equivalent circuit of a semiconductor gas sensor (heater, signal line common ground type).

As shown in the equivalent circuit of FIG. 3, the output voltage Vout of one or more standard gases is expressed by the voltage distribution formula of the power supply voltage Vcc, the load resistance, and the sensor resistance Rs, , And the resistance value of the sensor can be known by using it, and the output characteristic graph of the gas sensor can be generated as shown in (a) of FIG. 2 by changing it to the log value. This is referred to as basicization (calibration), and when basicization is performed, the gas concentration can be grasped by converting the output voltage Vout of an arbitrary gas into a logarithm of the resistance. R'is the load resistance of the sensor, 'Vcc' is the power supply voltage, and 'Vout' is the output voltage. In this case, 'Vh' is the heater voltage, 'Rh' is the heater resistance, Respectively.

However, the resistance value of the sensor material changes according to the temperature, humidity, storage conditions, etc., and the accuracy of the sensor is degraded when the sensor characteristic changes from 'a' curve to 'b' curve or 'd' curve in FIG. If the characteristic of the sensor based on the 'a' curve is changed to a 'b' curve, the sensor resistance is shown as 10 kΩ for 80 PPM of alcohol gas, which is 320 PPM Is displayed. On the other hand, if the curve is changed to a "d" curve, the sensor resistance is shown as 30 kΩ for 80 PPM of alcohol gas, which is expressed as 20 PPM based on the basic state. That is, a large error may occur in the detection result depending on the change of the sensor characteristic.

In this case, it is necessary to carry out the regeneration, but it is difficult for the user to prepare gas of the standard concentration, and since there is no description of the basicization, it is inconvenient to carry out the regeneration by leaving the apparatus to the manufacturer. The standard gas had to be injected from the outside of the gas detector through a separate standard gas reservoir, and the work had to be done by the operator.

Patent Registration No. 10-0497991 (Publication Date: Jul. 01, 2005)

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a gas detector in which a standard gas used for re- Or standard gas reservoirs are built in, and the gas detectors can be re-ignited while the standard gas is injected according to a predetermined period or a user's arbitrary selection, and the standard gas consumption to be used is counted through the number of injections So that it is possible to know the replacement timing of the gas detector.

Other objects and advantages of the present invention will be described hereinafter and will be understood by the embodiments of the present invention. Further, the objects and advantages of the present invention can be realized by the means and the combination shown in the claims.

In order to solve the above-described problems, the present invention provides a gas detector comprising: a gas inlet port through which gas is introduced into a gas detector; A gas sensor (30) connected to the gas inlet (20) in the gas detector (10) to the first connection pipe (40); A check valve (50) installed in the first connection pipe (40); A standard gas reservoir built in the gas detector 10 is provided so that the standard gas stored at the preset pressure is supplied to the first connection pipe 40 so that the gas sensor 30 can be re- (70) and the first connection pipe (40) are connected to the standard gas reservoir (70) and the second connection pipe (60) A control valve (80) for injecting gas into the gas sensor (30) side; And a control unit.

As described above, the present invention has an effect that it is not necessary to separately receive the standard gas used for regenerating the gas detector from the outside.

In addition, the present invention has a built-in standard gas reservoir inside the gas detector, and the standard gas reservoir has a detachable structure.

Further, the present invention has the effect of enabling the gas detector to be regenerated in real time automatically or at a desired moment by the user at every preset period through the built-in standard gas reservoir.

In addition, the present invention does not go to a separate calibration center or a manufacturer when a calibration is required because the reference value of the sensor is wrong during the use of the gas measuring / detecting device, and the user simply performs re-basicization to always maintain a high level of accuracy .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of a standard gas reservoir installation structure of a gas detector incorporating a rechargeable standard gas according to the present invention; FIG.
FIG. 2 is a graph showing the resistance change according to the alcohol concentration of the portable alcohol detector (alcohol meter) and the output characteristic value when the sensor reference value changes. FIG.
3 is a circuit diagram showing an equivalent circuit of a semiconductor gas sensor (heater, signal line common ground type).
4 is a block diagram of a gas detector according to an embodiment of the present invention.
FIG. 5 and FIG. 6 are flowcharts of the re-ignition control unit and the gas concentration measurement control unit for the re-ignition process and the gas-actual process of the gas detector according to the embodiment of the present invention, respectively.

Before describing in detail several embodiments of the invention, it will be appreciated that the application is not limited to the details of construction and arrangement of components set forth in the following detailed description or illustrated in the drawings. The invention may be embodied and carried out in other embodiments and carried out in various ways. It should also be noted that the device or element orientation (e.g., "front,""back,""up,""down,""top,""bottom, Expressions and predicates used herein for terms such as "left,"" right, "" lateral, " and the like are used merely to simplify the description of the present invention, Or that the element has to have a particular orientation. Also, terms such as " first "and" second "are used herein for the purpose of the description and the appended claims, and are not intended to indicate or imply their relative importance or purpose.

The present invention has the following features in order to achieve the above object.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined.

Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.

In one embodiment of the present invention, a gas injection port 20 is provided through the inside of the gas detector 10 and into which a measurement gas flows. A gas sensor (30) connected to the gas inlet (20) in the gas detector (10) to the first connection pipe (40); A check valve (50) installed in the first connection pipe (40); A standard gas reservoir built in the gas detector 10 is provided so that the standard gas stored at the preset pressure is supplied to the first connection pipe 40 so that the gas sensor 30 can be re- (70) and the first connection pipe (40) are connected to the standard gas reservoir (70) and the second connection pipe (60) A control valve (80) for injecting gas into the gas sensor (30) side; And a control unit.

The control valve 80 is automatically opened to the control valve 80 at predetermined time intervals through a control unit provided in the gas detector 10 and the standard gas is injected into the gas sensor 30 to control the gas sensor 30 The control valve 80 is opened via the control unit and the standard gas is supplied to the gas sensor 10 through the control unit so that the control valve 80 can be automatically regenerated every preset period or the regenerator key installed in the gas detector 10 can be operated manually. (30) so that the gas sensor (30) can be regenerated in real time.

The number of times of use of the gas sensor 30 is counted while the control valve 80 is opened through the control unit provided in the gas detector 10 so that the standard gas reservoir 70 can be replaced And the standard gas reservoir (70) is detachable in the gas detector (10).

In addition, the method for regenerating the gas detector includes a first step of detecting whether the user inputs a regenerating key in the gas detector; A second step of storing the regenerated value of the output value of the gas sensor according to the concentration of at least one standard gas delivered to the gas sensor; A third step of assigning the output value of the gas sensor to a formula for calculating an arbitrary concentration according to the concentration of the re-basifying gas introduced into the gas detector; And a control unit.

Hereinafter, a gas detector with built-in rechargeable gas standard according to a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 to 6. FIG.

The regenerated standard gas type gas detector according to the present invention includes a gas inlet 20, a gas sensor 30, a check valve 50, a standard gas reservoir 70, and a control valve 80.

The gas injection port 20 has a shape penetrating from the left to the right inside the upper end of the gas detector (housing) 10, and is a portion into which the measurement gas A is injected.

The gas sensor 30 may be a variety of sensors depending on the user's embodiment, such as a semiconductor type gas sensor, a contact combustion type gas sensor or an electrochemical type gas sensor. The gas sensor 20 is connected to the gas inlet 20 and the first connection pipe 40 through the first connection pipe 40 connected to the gas inlet 20, 30 and then discharged through a discharge pipe 41 provided outside the gas detector 10 at the rear end of the gas sensor 30. [

That is, in the gas sensor 30, the measurement gas is measured and the gas concentration of the measurement gas is known through the control unit in the gas detector 10. The gas measuring method and the regenerating method of the gas detector 10 through the gas sensor 30 will be described below.

The first connection pipe 40 connecting the gas sensor 30 and the gas injection port 20 is provided with a check valve 50 so that the gas sensor 30 is connected to the gas sensor 30, So that the measurement gas (A) or the standard gas (B) can flow only to the gas sensor (30) side in the second connection pipe (60).

The standard gas reservoir 70 stores a standard gas to be used when the gas detector 10 is regenerated. The standard gas reservoir 70 is embedded in the gas detector 10, Possible replacement is possible.

In addition, according to a user embodiment, one or more of these standard gas reservoirs 70 may be mounted in the interior of the gas detector 10.

The standard gas reservoir 70 is connected to the first connection pipe 40 through the second connection pipe 60 which is another connection pipe so that the standard gas reservoir 70 So that the standard gas stored in the gas sensor 30 can be introduced into the gas sensor 30 through the second and one connection pipes.

The standard gas reservoir 70 is provided in the gas detector 10 so that the number of times of use of the gas sensor 30 is counted while the control valve 80 is opened through a control unit provided in the gas detector 10, .

The control valve 80 is provided in the second connection pipe 60. In the second connection pipe 60, the control valve 80 is opened or closed by the control unit, and the control valve 80 The standard gas is injected into the gas sensor 30 only when the gas sensor 30 is opened (when the gas detector 10 is restarted).

The control valve 80 is automatically opened to the control valve 80 at predetermined time intervals through the control unit provided in the gas detector 10 and the standard gas is injected into the gas sensor 30, The control valve 80 is opened via the control unit and the standard gas is supplied to the gas sensor 10 through the control unit so that the control valve 80 can be automatically regenerated every preset period or the regenerator key installed in the gas detector 10 can be operated manually. (30) so that the gas sensor (30) can be regenerated in real time.

Hereinafter, the re-ignition method of the re-ignition standard gas built-in type gas detector of the present invention will be described.

FIG. 2 (a) is a graph showing the gas concentration and the sensor output, which are generated based on the values calibrated by one or more standard gases, as log values. FIG.

3 is a circuit diagram showing an equivalent circuit of a gas sensor (heater, signal line common ground type).

4 is a block diagram of a gas detector according to an embodiment of the present invention.

Referring to FIG. 5, the gas detector according to the present embodiment includes:

At the time of regeneration, at least one standard gas is injected and the gas sensor output value is stored in the memory unit. The calculation unit generates a sensor output graph based on the concentration of the standard gas. That is, based on the graph generated by the calibration value as shown in FIG. 2 (A), the concentration can be calculated when an arbitrary concentration gas is injected into the sensor.

The re-initialization is performed by the user in order to make accurate measurement when the calibration value of the sensor changes as shown in (B) or (C) of FIG. If the user presses the regeneration button or automatically performs regeneration at the set time, the regeneration standard gas is injected into the gas sensor, and an arbitrary concentration can be calculated based on the reference gas.

5 and 6 are flow charts of the re-initialization of the operation unit 35 and the gas concentration measurement for the re-initialization process and the gas actual process of the gas detector according to the embodiment of the present invention, respectively.

If the user wants to regenerate, press the regenerating key located on the outside of the gas sensor, the regenerating mode starts. If the user wishes to measure the actual gas concentration, the measuring key is pressed to start the measuring mode. It is not necessary to separately set the re-initialization key and the measurement key, and it is possible to divide the pressing time of the button into two steps to determine whether the re-initialization key input or the measurement key input is performed.

Referring to FIG. 5, the control unit 37 checks whether there is a re-key input from the button input unit 30 (step 10). If there is a re-key input, the injection port of the gas injection unit 31 is opened for a certain period of time to receive the standard gas for resumption (11).

Next, the control unit controls the operation unit 35 to read the measurement result of the gas sensor 36 by the injection of the gas (12)

Then, the control unit controls the arithmetic unit to replace the pre-stored calibration value in the memory unit 34 with a new value and store it again, and ends the process.

Referring to FIG. 6, the controller 37 checks whether there is a measurement key input from the button input unit 30 (20). If there is a measurement key input, the injection port of the gas injection unit 31 is opened for a predetermined time to receive the measurement target gas (21).

Next, the control unit 37 controls the calculation unit to read the output value of the gas sensor 36 by injection of the gas to be measured (22).

Subsequently, the control unit controls the gas concentration to be calculated by substituting the output value into the arbitrary concentration calculation formula generated by the arithmetic operation unit, and displays the gas concentration on the display unit 32 (24) , And terminates the process.

In the present invention, the output value of the gas sensor 36 that reacts with the gas may be irregular depending on the environment. However, accurate measurement results can be obtained at any time by re-initializing the standard gas for re-basification at any time.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be apparent to those of ordinary skill in the art.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is to be understood that various changes and modifications may be made without departing from the scope of the appended claims.

10: gas detector 20: gas inlet
30: gas sensor 40: first connection pipe
41: discharge pipe 50: check valve
60: Second connector 70: Standard gas reservoir
80: Control valve
A: Measuring gas B: Standard gas

Claims (3)

A gas inlet 20 installed to penetrate inside the gas detector 10 and into which a measurement gas flows; A gas sensor (30) connected to the gas inlet (20) in the gas detector (10) to the first connection pipe (40);
A check valve (50) installed in the first connection pipe (40); A standard gas reservoir built in the gas detector 10 is provided so that the standard gas stored at the preset pressure is supplied to the first connection pipe 40 so that the gas sensor 30 can be re- (70);
The standard gas reservoir 70 is installed in the second connection pipe 60 connecting the standard gas reservoir 70 and the first connection pipe 40 so that the standard gas in the standard gas reservoir 70 is supplied to the gas sensor 30) side of the control valve 80; / RTI &gt;
The gas sensor 30 is connected to the gas detector 10 at the rear end of the gas sensor 30 after the measurement gas passes through the gas sensor 30 through the first connection pipe 40 connected to the gas inlet port 20, And is discharged through an externally installed discharge pipe 41,
The control valve (80)
The injection port of the control valve 80 and the gas injection unit 31 is automatically opened at predetermined time intervals through the control unit provided in the gas detector 10 to inject the standard gas into the gas sensor 30, ) Can be automatically re-initialized every preset period,
Or the regeneration key provided in the gas detector 10 is manually operated to open the inlet of the gas injection unit 31 for a predetermined time through the control unit to regenerate the standard gas for basicization from the gas sensor 30 so that the gas sensor 30 can be regenerated in real time,
The number of times the gas sensor 30 is injected into the standard gas storage container 70 is counted while the control valve 80 is opened through the control unit provided in the gas detector 10, And the standard gas reservoir (70) is removable in the gas detector (10). delete delete
KR1020150168517A 2015-11-30 2015-11-30 Gas detector using internal-type standard gas for re-calibration KR101913149B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020150168517A KR101913149B1 (en) 2015-11-30 2015-11-30 Gas detector using internal-type standard gas for re-calibration

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
KR1020150168517A KR101913149B1 (en) 2015-11-30 2015-11-30 Gas detector using internal-type standard gas for re-calibration

Publications (2)

Publication Number Publication Date
KR20170064047A KR20170064047A (en) 2017-06-09
KR101913149B1 true KR101913149B1 (en) 2018-10-31

Family

ID=59219919

Family Applications (1)

Application Number Title Priority Date Filing Date
KR1020150168517A KR101913149B1 (en) 2015-11-30 2015-11-30 Gas detector using internal-type standard gas for re-calibration

Country Status (1)

Country Link
KR (1) KR101913149B1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110274987A (en) * 2018-03-14 2019-09-24 光力科技股份有限公司 A kind of gas detecting system and its calibrating installation
CN109115259B (en) * 2018-09-06 2024-03-15 汉威科技集团股份有限公司 Standard gas conveying device

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4028006B2 (en) * 1996-06-17 2007-12-26 秀雄 植田 Analyzer for specific gas components in exhaled breath

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4028006B2 (en) * 1996-06-17 2007-12-26 秀雄 植田 Analyzer for specific gas components in exhaled breath

Also Published As

Publication number Publication date
KR20170064047A (en) 2017-06-09

Similar Documents

Publication Publication Date Title
KR100497991B1 (en) Portable gas detector and re-calibration method thereof
CN101368927B (en) Self-calibration gas sensor
EP3430319B1 (en) Air purifier and air purification method
US20020050161A1 (en) Method of identifying a gas and associated apparatus
JPS6055777B2 (en) Combustible sensor
Cretescu et al. Electrochemical sensors for monitoring of indoor and outdoor air pollution
US9128045B2 (en) Electrochemical sensor with zero calibration feature and method of calibrating
US20180292345A1 (en) Method and device for measuring concentration of substance in fluid
JP2016509219A (en) Residual oil measuring device
KR101940037B1 (en) Portable gas detector and re-calibration method thereof
KR101913149B1 (en) Gas detector using internal-type standard gas for re-calibration
JP2012047651A (en) Leak detector
JP5135058B2 (en) Leak detector
KR101256414B1 (en) water pollution measurement system by using gas sensor
TW200938836A (en) Hand-held systems and methods for detection of contaminants in a liquid
KR200453056Y1 (en) Volatile Organic Compounds Detector
KR20110100361A (en) Noxious gas sensor, method for detection
JP4175767B2 (en) Gas analyzer and calibration method thereof
CN105158311A (en) Universal oxygen gas analyzer and control method thereof
US10900928B2 (en) Gas sensor
US2786350A (en) Gas detection apparatus
JP3563399B2 (en) Gas analyzer
CN205049513U (en) Process analysis instrument
CN205229092U (en) Quick electrode of portable carbon dioxide gas improvement structure
JP4908683B2 (en) Nitric oxide analyzer and sensor element for measuring nitric oxide

Legal Events

Date Code Title Description
A201 Request for examination
E902 Notification of reason for refusal
E90F Notification of reason for final refusal
E701 Decision to grant or registration of patent right
GRNT Written decision to grant