CN85105865A - gas concentration measurement instrument - Google Patents
gas concentration measurement instrument Download PDFInfo
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- CN85105865A CN85105865A CN85105865.5A CN85105865A CN85105865A CN 85105865 A CN85105865 A CN 85105865A CN 85105865 A CN85105865 A CN 85105865A CN 85105865 A CN85105865 A CN 85105865A
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- ultrasonic sensor
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Abstract
Utilize ultrasound wave velocity of propagation in gas that the dependent gas concentration measurement instrument of gas concentration is comprised a moistureproof ultrasonic sensor, it has one deck to utilize evaporation mode to be deposited on metal or similar material on the sealant surface.Therefore, this instrument is subjected to the influence of temperature and humidity hardly, can be in long-time continuous high-acruracy survey gas concentration under the high humility.This ultrasonic sensor is made of ultrasonic vibrator, support and encapsulant basically.Preferablely be, it is embedded in the piece and with the elaxtic seal sealing, forms the film of one deck conduction and/or non-conducting material on the vibration end face of encapsulant (elaxtic seal) surface, ultrasonic sensor and piece end face.
Description
The present invention relates to utilize the instrument of ultrasonic measurement gas concentration, more particularly, relate to a kind of highly moistureproof sonac, gas concentration measurement instrument of high-acruracy survey gas concentration for a long time of having used.
At present existing such surveying instrument, it utilizes hyperacoustic velocity of propagation the dependence of tested gas concentration to be measured the concentration of mixed gas or single component gas.The United States Patent (USP) № .4 that this gas concentration measurement instrument has been authorized in (for example) on September 2nd, 1980, narration to some extent in 220,040.This United States Patent (USP) is the same assignee who authorizes the application.At first its measuring principle will be described.
Ultrasonic velocity of propagation in mixed gas is determined by constant, concentration and the temperature of this mixed gas.In other words, its velocity of propagation can be explained with following equation:
In the formula: V is the velocity of propagation of ultrasound wave in mixed gas;
Cpi be in the mixed gas under the normal pressure situation specific heat of object gas i;
Cvi be in the mixed gas under the fixed volume situation specific heat of object gas i;
Mi is the molecular wt of object gas i in mixed gas;
Xi is the mole fraction of object gas i in the mixed gas;
R is a gas law constant;
T is the absolute temperature of mixed gas.
Suppose that mixed gas is by gas and carbon dioxide CO
2Form, equation (1) then can be rewritten as:
V
2＝（Cpco
2Xco
2+CpairXair）/
（Cvco
2Xco
2+CvairXair）·R·T……（2）
Constant and 293 ° of K substitutions of absolute temperature equation (2) with mixed gas just can calculate at each carbon dioxide CO
2The concentration situation in hyperacoustic velocity of propagation.Its result such as table 1 and shown in Figure 1.
Table 1
Since ∑ xi=1, so formula (2) can be provided by following formula (3) again:
V
2= ([Cpair+(Cpco
2-Cpair)Xco
2])/([Cvair+(Cvco
2-Cvair)Xco
2])
X (R·T)/([Mair+(Mco
2-Mair)Xco
2]) =G(X
2·T)……（3）
So, concentration Xco
2Just can provide by following formula (4):
Xco
2＝F（V·T） ……（4）
In other words, the concentration of object gas is the function of ultrasonic propagation velocity V and gas temperature T.
Fig. 2 is the block scheme according to a measuring system of the present invention, and it is based on above-mentioned principle and designs.
With reference to Fig. 2, ultrasonic sensor 1 comprises an emission oscillator 2 and a pick-up dipole 3 that is oppositely arranged with emission oscillator 2.With a kind of suitable method sonac 1 is installed in the object gas environment 4.The ultrasound wave that emits from emission oscillator 2 passes the ultrasound wave path 5 that contains object gas.By pick-up dipole 3 is received.Ultrasound wave passes the velocity of propagation of ultrasound wave path 5 and the concentration of object gas is inversely proportional to.Emission oscillator 2 comprises an electrostriction element.Driving amplifier 6 and negative immittance converter 7 are used to this signal generator of amplifying signal generator 8(by 10 controls of a feedback oscillation amplifier) high-frequency signal that produced and in order to improve its response characteristic.Pick-up dipole 3 comprises an electrostriction element.Prime amplifier 9 will amplify from the high-frequency signal of pick-up dipole 3 and its output signal will be delivered to feedback oscillation amplifier 10.Resistor 11 and negative immittance converter 12 are used to improve the response characteristic and the sensitivity of pick-up dipole 3.
On the other hand, the frequency f m of above-mentioned feedback oscillation system 13 and the ultrasound wave velocity of propagation V that passes path 5 in the target mixed gas has a kind of relation.Be fm=Kv/e(wherein e be distance between emission oscillator 2 and the pick-up dipole 3, K is a proportionality constant).So the frequency f m of system 13 and the fixed reference frequency f that crystal oscillator element 14 produces are closed in feedback oscillation
OBe added to frequency mixer 15, determine fm and f here
0Between difference frequency F.This value F is converted to a magnitude of voltage by frequency-voltage converter 16.And be sent to compensator 17.
Temperature sensor 18 comprises a thermistor, the thermopair of the temperature of a temperature measuring resistors or a kind of target gas environment 4, the temperature data that measures is added to temperature compensator 17, and this temperature compensator is used to eliminate the temperature dependency of ultrasonic propagation velocity.Output voltage after the temperature compensation is indicated by display unit 19, and this display unit comprises an aanalogvoltage table, a digital voltmeter or a register.
To describe in detail according to the present invention the carbon dioxide CO in the mixed gas with reference to Fig. 2 and Fig. 3
2(this mixed gas comprises three kinds of components to the example that gas concentration is measured: air, carbon dioxide CO
2With water vapour H
2O).
Accommodate 100% carbon dioxide CO
2The cylinder 20 of gas and a compression type air pump 21 are respectively carbon dioxide CO
2Gas and air are delivered to the flowmeter 22 and 23 with flow adjusted value, utilize the flow adjusted value to adjust carbon dioxide CO in advance
2Concentration.Be connected to one in flowmeter 22 and 23 back and be used to mix carbon dioxide CO
2With Air mixing chamber 24.The CO of mixing chamber 24
2Be introduced to a measuring chamber 25 with Air mixing gas by a conduit 26.In the bottom of measuring chamber 25 is that a depth of water is enough to conduit immersion tank 27 wherein.CO
2/ air gas mixture is passed tank 27 and is entered measuring chamber 25 from gas squit hole (it suitably is arranged among the conduit 26) ejection.By such process, the relative temperature in the measuring chamber 25 just is increased to up to 95 to 100%.Have one to stir fan on measuring chamber 25 tops, it is driven by motor 28.This function that stirs fan is the concentration unanimity that makes the mixed gas in the measuring chamber 25.Mixed gas passes the outside that a mixed gas outlet pipe 30 is discharged into measuring chamber 25.Sonac 1 according to the present invention is set at an appropriate location in the measuring chamber 25, and be connected with a calculation control system part 32 by a shielded cable 31, this calculation control part 32 comprises feedback oscillation system 13, crystal oscillator element 14, frequency mixer 15, frequency-voltage converter 16 and compensator 17.Temperature sensor 18 with a temperature measuring resistors, compensation temperature is connected with the compensator 17 of calculation control part 32 by a cable 33.The output voltage of compensator 17 is configured to 0 to 20 volt, corresponding to carbon dioxide CO
2The concentration of gas 0 to 20% volume, thus make the reading value of output voltage represent carbon dioxide CO
2The concentration of gas.For display unit, used a digital voltmeter, the frequency f m of feedback oscillation system 13 is by 34 monitoring of a frequency counter.The mixed gas of drawing by mixed gas outlet pipe 30 passes a delivery pipe 36 and is introduced into an infrared gas analyzer 35, measures carbon dioxide CO in this analyser
2The concentration of gas.In addition, a sampling section 37 of gas chromatogram is provided on the path of delivery pipe 36, makes carbon dioxide CO
2The concentration of gas is subjected to the check of gas chromatogram.
The thermistor temperature sensor 39 that is used to measure the mixed gas temperature is provided in measuring chamber 25, and this temperature is by 40 monitoring of a thermometric instruments.Except mixed gas inlet tube 41 and mixed gas outlet pipe 30, measuring chamber 25 seals fully, in addition, measuring chamber 25 is to be positioned among the gas constant temperature oven 42 of a variable temperatures, this constant temperature oven can be controlled at ± 0.1 ℃ within so that the temperature in the measuring chamber 25 can arbitrarily be changed.
Like this, in this ultrasonic gas measurement of concetration instrument, flow through carbon dioxide CO flowmeter 22 and 23, that in 0 to 20% scope, change
2Gas concentration value is in fact measured in measuring chamber 25 under the situation of 27 ℃, 35 ℃ and 42 ℃ three different temperatures, by infrared ray gas analyzer 35 gentle body colour layer spectrometer 38 resulting measurement data such as tables 2 and shown in Figure 4.
Table 2
*The frequency of 1 ultrasonic gas concentration measurement system.
*The reading of 2 ultrasonic system concentration measurement systems.
From table 2 and Fig. 4 as can be seen.According to the frequency f m of the feedback oscillation system of ultrasonic gas concentration measurement system of the present invention with respect to gas chromatograph and the indicated linear feature of concentration of infrared ray gas analyzer.And, be very consistent by the indicated concentration of ultrasound wave concentration measurement system and gas chromatograph and the indicated concentration of infrared ray gas analyzer.
Though having related to measuring according to the present invention, the narration of front comprises three kinds of gas component (CO
2, air and H
2An embodiment of the method and system of gas concentration O).But the invention is not restricted to measure the complex of this mixed gas.
Hereinafter sonac will be described, this sensor is respectively applied in the ultrasonic emitting element of ultrasonic gas concentration measurement system and in the ultrasound wave receiving element, its structure of sensor that includes these elements is identical with the structure of traditional sensors.That is to say that the sensor of this structure is made of a ultrasonic vibrator (for example PZT piezoelectric ceramics etc.).Its silver electrode is fused together, and is attached to (plate or support can be metal or plastic part) on a plate or the support.In measurement/control ultrasonic device, use this class sonac to carry out ultrasonic reception and emission so far always.Such sensor has a shortcoming.Promptly in the environment of water vapour, the lip-deep electrode of PZT and so on (for example silver electrode) is easily by electrocorrosion, so usually make ultrasonic signal become very difficult with correct conversion or its opposite correct conversion of electric signal.Therefore, be corroded, used a kind of encapsulant to prevent that water vapour from entering support such as silicones, epoxy resin or polycarbamate in order to prevent the electrode on the ultrasonic vibrator.Yet, although the ultrasonic vibrator of sonac is attached on the support and seals with a kind of encapsulant.But when it is in 80% to 100% the environment after the continuous working one to ten year in humidity.The progressively intrusion of water vapour will be gone wrong by sonac, also has another to tackle the measure of electrocorrosion,, uses a kind of metal support and welded seal that is.But being used for that ultrasonic vibrator is attached to the heat that adhesive resin on the metal support is easy to soldered generation damages.
Figure below is elaborated to prior art with reference to the accompanying drawings.Fig. 8 has represented the example of a traditional sonac.Fig. 8 a is the cross sectional view of sonac 59.Fig. 8 b is that ultrasonic vibrator 4s(for example make by the material of voltage electroceramics material PZT and so on or the resin with piezoelectric property) the amplification cross sectional view and its peripheral part.
Shown in Fig. 8 b, ultrasonic oscillator 4s goes up with electrode 60 and 61, with the adhesive 62 with good ultrasonic propagation characteristic this oscillator 45 is bonded on the support 44 (support 44(for example) and is made by metal or resin).By lead 46 and 47, electrode 60 and 61 is connected on terminal 48 and 49, and these terminals are fixed on (pedestal 50 is made by phenol resin laminate or epoxy laminated plate) on the pedestal 50, shown in Fig. 8 a and 8b.Use encapsulant 51 that pedestal is sealed.But this structure has a shortcoming.When continuous working in the environment that is containing water vapour for a long time in (for example 1 to 10 year), water vapour enters support 44 by encapsulant 51, makes electrode 60 and 61 by electrocorrosion.So can not correctly transmit and receive ultrasound wave.
Be summary of the present invention below.
The purpose of this invention is to provide a kind of gas concentration measurement instrument device, it uses a kind of ultrasonic sensor to be used as hyperacoustic element that transmits and receives, by forming one deck steam-preventing film on the surface of ultrasound wave concentration sensor.It can long-time continuous ground correct measurement gas concentration.
According to the present invention, a kind of gas concentration measurement system that uses the damp-proof ultrasonic sensor is provided, this ultrasonic sensor consists essentially of a ultrasonic oscillator, a support and a kind of encapsulant is characterized in that forming layer of conductive material and/or non-conducting material on the surface of encapsulant.
Be effect of the present invention below.
According to the present invention, on the encapsulant of traditional ultrasonic sensor, form thin film, thereby improved the humidity impedance of traditional ultrasonic sensor widely.Therefore, in the ultrasonic gas measurement of concetration instrument employed ultrasonic sensor can be in including the environment of water vapour continuous working for a long time.Done a kind of accelerated test for the ultrasonic sensor with film that is used for the present invention and traditional ultrasonic sensor, its result as shown in figure 10.In this test, each ultrasonic sensor is all invaded in 60 ℃ the hot water, and adds a DC voltage.In Figure 10, Y axis Y 66 expressions are the insulation resistance of unit with megaohm (M Ω).Abscissa 65 is the time of test.The curve 63 of employed ultrasonic sensor with film and the curve 64 of conventional ultrasound wave sensor among the present invention shown in Figure 10 are compared.The used sensor of the present invention does not change aspect insulation resistance as can be seen, we can say that perhaps its humidity impedance is fine.In addition, ultrasonic sensor or Fig. 5 extremely ultrasonic sensor shown in Figure 7 are embedded in the piece 67, and form thin film on elaxtic seal 75, piece 67 and vibration surface 71, thereby its humidity impedance is further increased.
Therefore, the influence of having used the ultrasonic gas concentration measurement system of this ultrasonic sensor (its humidity impedance is improved greatly) changed by temperature and humidity, it can be in high temperature environment the accurate concentration of measurement gas continuously for a long time, this specific character is industrial very useful.
Be brief description of drawings below.
Fig. 1 has represented CO
2Relation between gas concentration and the ultrasonic propagation velocity;
Fig. 2 is the block scheme of an example of measuring system;
Fig. 3 has represented a gas concentration measurement systematic survey CO
2A method example of gas concentration;
Fig. 4 is the diagram of the data in the table 2;
Fig. 5 to Fig. 7 is the sectional view of ultrasonic sensor example used among the present invention;
Fig. 8 a is the sectional view of traditional ultrasonic sensor;
Fig. 8 b is the ultrasonic oscillator 45 of the sensor shown in Fig. 8 a and the amplification sectional view of its peripheral part;
Fig. 9 is the sectional view of the example of ultrasonic sensor used among the present invention;
Figure 10 has represented among traditional sensors and the present invention the anti-moisture test result with the sensor of usefulness.
Be the explanation of optimum implementation of the present invention below.
To be narrated the present invention with reference to accompanying drawing.
Fig. 5 to Fig. 7 is employed ultrasonic sensor 43,53 and 56 a side cross-sectional view among the present invention, and the basic structure of each sensor is identical with traditional ultrasonic sensor structure shown in Figure 8.Ultrasonic sensor 45 has electrode 60 and 61, and blended rubber mixture 62 is bonded in it on support 44, shown in Fig. 8 b.By lead 46 and 47, electrode 60 and 61 is connected to terminal 48 and 49. Terminal 48 and 49 is fixed on the pedestal 50, and encapsulant 51 is topped with it, so that support 44 is sealed.
Fig. 5 has represented a kind of ultrasonic sensor 43 that forms film 52 on the surface of encapsulant 51.The material of this film 52 may be a non-conducting material, specifically is exactly silicon oxide sio, silicon dioxide SiO
2Perhaps a kind of fluoro resin such as teflon can utilize methods such as (for example) vacuum evaporation, sputter or ion plating that they are deposited as film.The thickness range of film should be 500
More than.Preferably from 1500
To 3000
Because film 52 is non-conductive, so passing terminal 48 that encapsulant 51 stretches out from support 44 and 49 part must cover in teflin tape or similar material, so that 52 of films are deposited on the surface of encapsulant 51, and can be deposited on other position.
Fig. 6 has represented a ultrasonic sensor that forms dielectric film 54 and 55 on terminal 48 and 49, were it not for this layer dielectric film, and terminal 48 and 49 will be gone up the film 57 that forms with encapsulant 51 surfaces and contact.The material of film 57 must be a kind of conductive material, and they can form by the method for (for example) vacuum evaporation, sputter or ion plating.These materials specifically can be aluminium Al, golden Au, plumbous Pb, copper Cu, titanium alloy, nickel, chromium Cr, molybdenum disulfide M.S
2Or magnesium fluoride Mg F
2The thickness range of film is 500
To 5000
Within, be preferably in 1500
To 3000
Within.Because film 57 conducts electricity, so dielectric film 54 and 55 is formed on the surface area of terminal 48 and 49, otherwise terminal 48 and 49 will contact with pedestal 50, encapsulant 51 and film 57.Terminal 48 that passes encapsulant 51 and stretch out from support 44 and 49 part must cover in teflin tape or similar material, so that 52 of films are deposited on the surface of encapsulant 51, and can not be deposited on other position.
Fig. 7 has represented a ultrasonic sensor 56 with film 58, and this film is formed on the surface of encapsulant 51 and on the surface area of terminal 48 and 49.If there is not film 58, this terminal 48 and 49 surface will contact with formed film 57 on the film 58.The material of film 58 must be any insulating material.They can be shaped by the method for vacuum evaporation, sputter or ion plating, specifically, and their preferably a kind of insulating material with linear expansion coefficient.This expansion coefficient is between the expansion coefficient of encapsulant 51 and film 57.The thickness range of film 58 is 100
To 4000
Between, be preferably 500
To 1000
Between.In addition, when film 58 and 57 forms, pass encapsulant 51 and the terminal 48 that stretches out from support 44 and 49 part will cover in teflon or similar material, so that 58 of films are deposited on the surface of terminal 48 and 49.And can not be deposited on other places, otherwise it will contact with film 57; Equally, 57 of films are deposited on the part of terminal 48 and 49 surperficial formed films 58, and can not be deposited on other places.
The material of the ultrasonic oscillator 45 of employed sensor, support 44, pedestal 50 and encapsulant 51 can be identical with the above-mentioned part material of traditional sensors among the present invention.That is to say that the material of ultrasonic oscillator can be the piezoceramic material of PZT and so on, and the resin with piezoelectric property.The material of retainer can be the stacked pressuring plate of a kind of phenolics, epoxy resin and so on.Encapsulant can be silicones, epoxy resin, polycarbamate or similar material.
Fig. 9 has represented to be embedded in the ultrasonic sensor 68 in the piece 67, and this sensor is with identical with reference to sensor that Fig. 5 to Fig. 7 narrated.This piece can improve moisture-proof function.Piece 67 shown in Figure 9 is made by a kind of corrosion resistant metal (for example aluminium or stainless steel) or synthetic resin.Ultrasonic sensor 68 is placed in the sensor support part 70 that piece 67 is close in suitable position at the end face 69 of terminal 48 and 49 1 sides, so the vibration end face 71 of ultrasonic sensor 68 flushes with the piece end face 72 of piece 67 basically.Be inserted with all elaxtic seals 74 and 75 that silicones or rubber and so on are arranged in the annular gap 73 between ultrasonic sensor 68 and piece 67, they can absorb the ultrasonic vibration of ultrasonic sensor 68, thereby ultrasonic sensor 68 is fixed on the piece 67.Two-wire cable 76 sends to the ultrasound wave high-frequency signal terminal 48 and 49 and receive the ultrasound wave high-frequency signals from terminal 48 and 49 of ultrasonic sensor 68.The aperture 77 that this root cable 76 passes on piece 67 left sides links to each other with 49 with terminal 48.For the purpose of sealing, the gap between piece 67 and the cable 76 is filled up with screw-thread bush or high moisture-resistant resin (for example polybutadiene polyvinylidene chloride).
Though in this embodiment, formed two kinds of films 78 and 79, no matter be that film 78 or 79 can form separately.This depends on the cooperation of the material of elaxtic seal 75, piece 67 and vibration end face 71.
Claims (4)
1, a kind of gas concentration measurement instrument device, it comprises: the signal generator by feedback amplifier control; The driving amplifier that the high-frequency signal that said signal generator produced is amplified; A ultrasonic sensor that has comprised ultrasonic emitting element and ultrasound wave receiving element, this ultrasonic emitting element is made of a kind of electrostriction type oscillator, be used for the high-frequency signal that said driving amplifier amplifies is converted to ultrasound wave, and launch this ultrasound wave, and this ultrasound wave receiving element also is made of a kind of electrostriction type oscillator, be used to receive said ultrasound wave, and be converted into electric signal; A feedback oscillation system that forms in negative immittance converter, resistance and another negative immittance converter, previous negative immittance converter is connected between said ultrasonic emitting element and the driving amplifier, and another negative immittance converter is then in parallel with said ultrasound wave receiving element; A prime amplifier that links to each other with the input of feedback amplifier; Comprise that is also calculated an output system, this calculating output system comprises a frequency mixer, in order to produce the difference frequency between feedback oscillation system frequency and the crystal resonator reference frequency; A frequency-voltage converter is used for difference frequency with the output of said frequency mixer and is converted to the compensator that voltage and temperature information that is detected according to the output and the temperature sensor of said frequency-voltage converter calculate gas concentration.Being characterized as of this gas concentration measurement instrument: said ultrasonic sensor is a kind of moistureproof ultrasonic sensor, it is made of a ultrasonic oscillator, a support and a kind of encapsulant basically, deposits the film of layer of conductive material and/or non-conducting material on the surface of encapsulant.
2, according to the gas concentration measurement instrument device of claim 1, wherein the film that is deposited on the encapsulant of said ultrasonic sensor is made of at the conductive material membrane that the non-conducting material film that deposits on the encapsulant and one deck deposit on said non-conducting material film one deck.
3, according to the gas concentration measurement instrument device of claim 1, wherein said ultrasonic sensor is embedded in the piece, and forms one deck non-conducting material and/or layer of conductive material film on the end face of the vibration end face of elaxtic seal, ultrasonic sensor and piece.
4, according to the gas concentration measurement instrument device of claim 2, wherein said ultrasonic sensor is embedded in the piece, and forms the film of one deck non-conducting material and/or layer of conductive material on the end face of the vibration end face of elaxtic seal, ultrasonic sensor and piece.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP109420/85 | 1985-05-23 | ||
| JP60109420A JPH0617897B2 (en) | 1985-05-23 | 1985-05-23 | Gas concentration measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN85105865A true CN85105865A (en) | 1986-11-19 |
| CN1011441B CN1011441B (en) | 1991-01-30 |
Family
ID=14509790
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 85105865 Expired CN1011441B (en) | 1985-05-23 | 1985-08-02 | Measuring instrument for gas density |
Country Status (2)
| Country | Link |
|---|---|
| JP (1) | JPH0617897B2 (en) |
| CN (1) | CN1011441B (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103425099A (en) * | 2013-07-16 | 2013-12-04 | 广东工业大学 | Embedded carbon emission monitoring and detecting system implemented in vulcanization procedures |
| CN104126027A (en) * | 2011-11-22 | 2014-10-29 | 英飞康公司 | Multi-chambered acoustic sensor for determining gas composition |
| CN107246923A (en) * | 2017-08-07 | 2017-10-13 | 李昕虎 | A kind of thermometer and thermometry based on TPoS resonators |
| CN108474764A (en) * | 2015-11-06 | 2018-08-31 | Qorvo美国公司 | Acoustic resonator equipment and offer air-tightness and surface-functionalized manufacturing method |
| CN110957178A (en) * | 2019-12-13 | 2020-04-03 | 四川新能电力有限公司 | Vacuum switch online detection method |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7677101B2 (en) * | 2003-12-30 | 2010-03-16 | 3M Innovative Properties Company | Estimating propagation velocity through a surface acoustic wave sensor |
| CN100465613C (en) * | 2005-06-28 | 2009-03-04 | 上海理工大学 | Method and its device for on-line detecting atmospheric particulate matter concentration |
| WO2010109363A2 (en) * | 2009-03-23 | 2010-09-30 | Koninklijke Philips Electronics, N.V. | Gas sensing using ultrasound |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS554528A (en) * | 1978-06-27 | 1980-01-14 | Sumitomo Bakelite Co Ltd | Method and apparatus for measuring gas concentration |
| JPS58136734U (en) * | 1982-03-11 | 1983-09-14 | 日本電子機器株式会社 | Notking sensor |
| JPS6166126A (en) * | 1984-09-10 | 1986-04-04 | Sumitomo Bakelite Co Ltd | Moisture resisting type ultrasonic wave sensor |
-
1985
- 1985-05-23 JP JP60109420A patent/JPH0617897B2/en not_active Expired - Lifetime
- 1985-08-02 CN CN 85105865 patent/CN1011441B/en not_active Expired
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104126027A (en) * | 2011-11-22 | 2014-10-29 | 英飞康公司 | Multi-chambered acoustic sensor for determining gas composition |
| US9217663B2 (en) | 2011-11-22 | 2015-12-22 | Inficon, Inc. | Multi-chambered acoustic sensor for determination gas composition |
| CN103425099A (en) * | 2013-07-16 | 2013-12-04 | 广东工业大学 | Embedded carbon emission monitoring and detecting system implemented in vulcanization procedures |
| CN103425099B (en) * | 2013-07-16 | 2014-08-06 | 广东工业大学 | Embedded carbon emission monitoring and detecting system implemented in vulcanization procedures |
| CN108474764A (en) * | 2015-11-06 | 2018-08-31 | Qorvo美国公司 | Acoustic resonator equipment and offer air-tightness and surface-functionalized manufacturing method |
| CN108474764B (en) * | 2015-11-06 | 2021-12-10 | Qorvo美国公司 | Acoustic resonator device and manufacturing method providing gas tightness and surface functionalization |
| CN107246923A (en) * | 2017-08-07 | 2017-10-13 | 李昕虎 | A kind of thermometer and thermometry based on TPoS resonators |
| CN110957178A (en) * | 2019-12-13 | 2020-04-03 | 四川新能电力有限公司 | Vacuum switch online detection method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61269061A (en) | 1986-11-28 |
| CN1011441B (en) | 1991-01-30 |
| JPH0617897B2 (en) | 1994-03-09 |
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