US3613665A - Sampling means for exhaled air - Google Patents
Sampling means for exhaled air Download PDFInfo
- Publication number
- US3613665A US3613665A US848587A US3613665DA US3613665A US 3613665 A US3613665 A US 3613665A US 848587 A US848587 A US 848587A US 3613665D A US3613665D A US 3613665DA US 3613665 A US3613665 A US 3613665A
- Authority
- US
- United States
- Prior art keywords
- time delay
- port
- valve
- air
- signal
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Lifetime
Links
- 238000005070 sampling Methods 0.000 title claims description 24
- 238000010438 heat treatment Methods 0.000 claims description 3
- 230000000977 initiatory effect Effects 0.000 claims description 2
- 238000007599 discharging Methods 0.000 abstract description 4
- 241001465754 Metazoa Species 0.000 abstract description 3
- 230000029058 respiratory gaseous exchange Effects 0.000 abstract description 3
- 239000003570 air Substances 0.000 description 30
- 239000007789 gas Substances 0.000 description 9
- 239000000203 mixture Substances 0.000 description 6
- 241000124008 Mammalia Species 0.000 description 2
- 239000012080 ambient air Substances 0.000 description 2
- 230000000295 complement effect Effects 0.000 description 2
- 210000004072 lung Anatomy 0.000 description 2
- 241000282412 Homo Species 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000037037 animal physiology Effects 0.000 description 1
- 239000003990 capacitor Substances 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
Images
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/08—Detecting, measuring or recording devices for evaluating the respiratory organs
- A61B5/097—Devices for facilitating collection of breath or for directing breath into or through measuring devices
Definitions
- the first portion of such mixture exhaled by a mammal consists principally of ambient air in passageways between the point of exhalation and the main airways of the lung.
- the first portion merges into the second portion of the exhaled mixture which consists of the residual ambient air and alveolar gas; that is, the gas contained in the cells of the lung.
- the last portion of the exhaled mixture consists principally of the alveolar gas, and is also known as end tidal air. This last portion of the exhaled mixture which is of primary interest in human and animal physiology for diagnostic and analytical purposes.
- a valve permits discharge of a preselected portion of exhaled air and is then operated to divert a selected terminal portion for analysis.
- the sensor is a self-heating resistance device, adapted, when cooled by the exhaled air, to initiate the time delay, and when heated, during the inhalation cycle, to disarm the time delay in preparation for the next inhalation cycle.
- FIG. 1 is a sectional view of the diverted valve used in the sampling means for exhaled air, the view being taken through 1-1 of FIG. 2.
- FIG. 2 is a sectional view of the diverter valve, taken through 2-2 of FIG. 1.
- FIG. 3 is a block diagrammatical view indicating the electrical components of the sampling means as well as apparatus with which the sampling means is used.
- the sampling means for exhaled air includes a diverter valve 1, having a valve body 2 which may comprise a pair of complementary components, and forming an inlet 3.
- the inlet communicates with a valve chamber 4, having converging walls 5 and an apex end 6.
- One of the walls 5 is provided with an opening which receives a seal ring having intumed flanges forming a diverter port 7, and the other wall is provided with a similar opening which receives a similar seal ring forming an exhaust port 8.
- the seal rings project into the valve chamber and are held in place by suitable retainer fittings 9, attached by screws 10.
- the apex end 6 of the valve chamber receives a pivot shaft II, the ends of which are joumaled in bearings 12.
- the pivot shaft 11 supports a gate valve 13, in the form of a flat disk. Oscillation of the pivot shaft moves the gate valve 13 between the diverted port 7 and exhaust port 8.
- control housing 14 which may be formed of complementary components, and contains a rotary solenoid 15, having a drive shaft 16, suitably engageable with the upper end of the pivot shaft 1 l.
- a temperature sensor 17 mounted in the control housing 14 is a temperature sensor 17; for example, a Thermistor.
- the temperature sensor includes a pair of supports 18, which extend into the valve chamber 4 adjacent the inlet 3 and are joined by a sensing element 18a in the form of a resistor.
- a screen cage 19 may be provided around the supports and sensing elements.
- the output of the sensor is capacitor coupled to a signal amplifier 20.
- the signal amplifier is a DC coupled amplifier which operates at very high gain. This causes the output of the amplifier to swing between positive and negative saturation, producing a low quality square wave whose period is equal to the swings of the input signal.
- This square wave is fed into a squaring amplifier 21, which increases the rise time of the square wave to a point that it can be used to trigger a time delay 22 which may be a monostable multivibrator.
- the multivibrator is arranged so that it may be varied over a range of 0.] second to approximately 10 seconds.
- the output of the monostable multivibrator or time delay, in conjunction with the output of the squaring amplifier 21, is fed to the input of a two input NAND-gate 23.
- the NAND gate produces a signal at its output only if the following two conditions are satisfied:
- the time delay has finished its time period and returned to its original state.
- a silicon controlled rectifier power switch 24 is caused to turn on.
- the output of the switch is filtered DC which is applied to the rotary solenoid 15.
- the inlet 3 of the diverter valve is connected to an exhalation line 25, which is connected to the patient through a breathing apparatus which includes an exhalation valve 26 connected to the exhalation line 25, and an inhalation valve 27.
- the two valves, 26 and 27, operate alternately as the patient inhales and exhales so that there is intermittent flow of air in the exhalation line.
- the diverter port communicates with a conventional analyzing means 28, capable of identifying the composition of gases received from the diverter valve.
- the temperature sensor element is supplied with sufficient current to maintain a normal temperature above F. so that the incoming air cools the sensor element by convection, thus changing its resistance.
- This resistance change is utilized to arm the control circuit comprising the signal amplifier, squaring amplifier, time delay, NAND gate and power switch, and also to start the time delay circuit within the time delay mechanism.
- the solenoid 15 is operated to close the exhaust port 8 and open the diverted port 7. By proper adjustment of the time delay, only the last portion of the exhaled gas is diverted. It is this last portion of the exhaled gas that is the end tidal or alveolar gas which is of primary interest.
- the temperature sensor 17 returns to its normal temperature terminating operation of the control circuit so that the time delay may return to its initial condition. This operation takes place during the interval that the patient is inhaling; that is during the inhalation cycle, the diverter port is closed and the exhaust port opened so that the apparatus is ready for the next exhalation cycle.
- a sampling means for diverting the end tidal portion of air exhaled by a patient and conveyed through an exhalation air line, and sampling means comprising:
- a diverter valve having an inlet arranged for connection to such line, an exhaust port, an outlet diverter port and means including a valve member normally in position closing said diverter port and movable to a position opening said diverter port and closing said exhaust port;
- valve-operating means including an electromagnet means connected to said valve member and efiective when energized to move said member to said position opening said diverted port;
- a sampling means as defined in claim 3 wherein:
- said time delay is a variable period monostable multivibraadjustable time delay means for adjustably delaying translimo" of recewed sgnalsi said Signal s F and said signal translating means comprises an amplifier inconnected to said electromagnet means for energizing the terposed between said thermistor and the time delay latter for operating said valve to cause said valve member
- a sampling means as defined in claim 4 wherein: v a i f f i 'i g i f r 3;?
- said signal translating means includes a two input NAND Se ficte unng passage 0 ex 6 m o Sal m e gate connected to receive signals from said amplifier and whereby to divert through said diverter port only the end tidal portion of the exhaled air.
Abstract
Description
Claims (5)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US84858769A | 1969-08-08 | 1969-08-08 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3613665A true US3613665A (en) | 1971-10-19 |
Family
ID=25303716
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US848587A Expired - Lifetime US3613665A (en) | 1969-08-08 | 1969-08-08 | Sampling means for exhaled air |
Country Status (1)
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Cited By (24)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3838971A (en) * | 1973-05-04 | 1974-10-01 | Borg Warner | Electrolytic alcohol detection |
US3886929A (en) * | 1971-09-20 | 1975-06-03 | Borg Warner | Breath tester null memory system |
US3910261A (en) * | 1974-06-11 | 1975-10-07 | Bourns Inc | End-tidal gas analysis apparatus for respirators |
US4016876A (en) * | 1973-11-06 | 1977-04-12 | Westinghouse Electric Corporation | Breathing apparatus |
US4157040A (en) * | 1975-12-10 | 1979-06-05 | General Electric Company | Apparatus for collecting pyrolysates from a gas-cooled dynamoelectric machine |
FR2420157A1 (en) * | 1978-03-16 | 1979-10-12 | Inst Nat Sante Rech Med | Flow selector for separating inhaled and exhaled gases - has electronically controlled shutter which opens or closes one of two pipes according to direction of gas flow |
FR2422380A1 (en) * | 1978-04-15 | 1979-11-09 | Draegerwerk Ag | METHOD AND DEVICE FOR IDENTIFYING AND SEPARATING THE FRACTION OF ALVEOLAR AIR CONTAINED IN THE RESPIRATORY AIR |
US4220162A (en) * | 1978-11-24 | 1980-09-02 | Intermountain Health Care | Alveolar gas sampling system and method |
FR2449436A1 (en) * | 1979-02-22 | 1980-09-19 | Draegerwerk Ag | METHOD AND DEVICE FOR DETERMINING THE MEASUREMENT TIME IN APPARATUSES FOR CONTROLLING THE ALCOHOL CONTENT OF EXPIRED AIR |
US4579826A (en) * | 1983-09-30 | 1986-04-01 | Bolton Craig E | Method and device for analyzing human breath |
US5211181A (en) * | 1991-05-17 | 1993-05-18 | Martek Corporation | Apparatus and method for collecting human breath samples |
EP0650051A2 (en) * | 1993-10-25 | 1995-04-26 | Kyoto Dai-ichi Kagaku Co., Ltd. | Expiration collecting method and automatic expiration collector |
US5555890A (en) * | 1992-06-08 | 1996-09-17 | University Of Southern California | Pharyngeal end-tidal carbon dioxide measuring catheter |
US5687593A (en) * | 1995-06-01 | 1997-11-18 | Hiatt And Company Limited | Handcuffs |
US6248078B1 (en) | 1998-08-31 | 2001-06-19 | Johns Hopkins University | Volatile biomarkers for analysis of hepatic disorders |
US20040138577A1 (en) * | 2002-12-20 | 2004-07-15 | Kline Jeffrey A. | Disposable hand-held device for collection of exhaled breath condensate |
US20050000517A1 (en) * | 2000-11-07 | 2005-01-06 | Eriksson Nils Olof | Arrangement in ventilatory treatment of the lungs |
US20050208614A1 (en) * | 2002-12-20 | 2005-09-22 | The Charlotte-Mecklenburg Hospital Authority | Utilizing lipopolysaccharide in exhaled breath condensate to diagnose gram negative pneumonia |
US20070073183A1 (en) * | 2003-02-14 | 2007-03-29 | The Charlotte-Mecklenburg Hospital Authority | Device and method for collection of exhaled alveolar breath condensate |
US20080009761A1 (en) * | 2006-06-21 | 2008-01-10 | Acker Jaron M | Ventilator breath condensate sampler and method of collecting a breath condensate sample |
US7422723B1 (en) | 2003-10-24 | 2008-09-09 | Alcohol Detection Systems, Inc. | Alcohol breath test device |
US20090044597A1 (en) * | 2005-06-25 | 2009-02-19 | Frank Kvasnik | Breath sampling device |
US20090320844A1 (en) * | 2006-08-04 | 2009-12-31 | Nielsen Joergen Groenlund | Method to compensate for the effect of recirculation of inert blood soluble gas on the determination of pulmonary blood flow in repeated inert gas rebreathing tests |
WO2011064759A1 (en) | 2009-11-30 | 2011-06-03 | Delmedica Investments Limited | Method and device for measurement of exhaled respiratory gas temperature |
Citations (10)
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US470489A (en) * | 1892-03-08 | Water cut-off | ||
US3026868A (en) * | 1962-03-27 | Respiration measuring apparatus and method | ||
US3196689A (en) * | 1963-04-18 | 1965-07-27 | Macquorn R Forrester | Breath constituent measurement apparatus and method |
US3238783A (en) * | 1962-09-07 | 1966-03-08 | Nat Res Dev | Breath sampling apparatus |
US3253711A (en) * | 1962-12-31 | 1966-05-31 | Pfaudler Permutit Inc | Fluid separation |
US3303840A (en) * | 1963-07-12 | 1967-02-14 | Etzlinger Lucien | Apparatus for collecting and analyzing alveolar gas from the lungs |
US3426745A (en) * | 1967-03-27 | 1969-02-11 | Bioconsultants Inc | Bag means for collecting breathing and rebreathing air samples |
US3429186A (en) * | 1966-10-11 | 1969-02-25 | Monsanto Co | Gas sample compositor |
US3509771A (en) * | 1964-03-04 | 1970-05-05 | Aerojet General Co | Breath sampling apparatus |
US3512393A (en) * | 1967-05-29 | 1970-05-19 | Leeds & Northrup Co | Gas sampling analyzing system |
-
1969
- 1969-08-08 US US848587A patent/US3613665A/en not_active Expired - Lifetime
Patent Citations (10)
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US470489A (en) * | 1892-03-08 | Water cut-off | ||
US3026868A (en) * | 1962-03-27 | Respiration measuring apparatus and method | ||
US3238783A (en) * | 1962-09-07 | 1966-03-08 | Nat Res Dev | Breath sampling apparatus |
US3253711A (en) * | 1962-12-31 | 1966-05-31 | Pfaudler Permutit Inc | Fluid separation |
US3196689A (en) * | 1963-04-18 | 1965-07-27 | Macquorn R Forrester | Breath constituent measurement apparatus and method |
US3303840A (en) * | 1963-07-12 | 1967-02-14 | Etzlinger Lucien | Apparatus for collecting and analyzing alveolar gas from the lungs |
US3509771A (en) * | 1964-03-04 | 1970-05-05 | Aerojet General Co | Breath sampling apparatus |
US3429186A (en) * | 1966-10-11 | 1969-02-25 | Monsanto Co | Gas sample compositor |
US3426745A (en) * | 1967-03-27 | 1969-02-11 | Bioconsultants Inc | Bag means for collecting breathing and rebreathing air samples |
US3512393A (en) * | 1967-05-29 | 1970-05-19 | Leeds & Northrup Co | Gas sampling analyzing system |
Non-Patent Citations (2)
Title |
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Lourence, J. J. et al., Control Engineering, Sept. 1967, p. 105, (copy in 73/421.5) * |
NASA Tech. Brief, No. 68 10438, Dec. 1968, (copy in 128/2.08) * |
Cited By (36)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3886929A (en) * | 1971-09-20 | 1975-06-03 | Borg Warner | Breath tester null memory system |
US3838971A (en) * | 1973-05-04 | 1974-10-01 | Borg Warner | Electrolytic alcohol detection |
US4016876A (en) * | 1973-11-06 | 1977-04-12 | Westinghouse Electric Corporation | Breathing apparatus |
US3910261A (en) * | 1974-06-11 | 1975-10-07 | Bourns Inc | End-tidal gas analysis apparatus for respirators |
US4157040A (en) * | 1975-12-10 | 1979-06-05 | General Electric Company | Apparatus for collecting pyrolysates from a gas-cooled dynamoelectric machine |
FR2420157A1 (en) * | 1978-03-16 | 1979-10-12 | Inst Nat Sante Rech Med | Flow selector for separating inhaled and exhaled gases - has electronically controlled shutter which opens or closes one of two pipes according to direction of gas flow |
US4248245A (en) * | 1978-04-15 | 1981-02-03 | Dragerwerk Aktiengesellschaft | Method and device for determining and separating the alveolar air proportion from the breathing air |
FR2422380A1 (en) * | 1978-04-15 | 1979-11-09 | Draegerwerk Ag | METHOD AND DEVICE FOR IDENTIFYING AND SEPARATING THE FRACTION OF ALVEOLAR AIR CONTAINED IN THE RESPIRATORY AIR |
US4220162A (en) * | 1978-11-24 | 1980-09-02 | Intermountain Health Care | Alveolar gas sampling system and method |
FR2449436A1 (en) * | 1979-02-22 | 1980-09-19 | Draegerwerk Ag | METHOD AND DEVICE FOR DETERMINING THE MEASUREMENT TIME IN APPARATUSES FOR CONTROLLING THE ALCOHOL CONTENT OF EXPIRED AIR |
US4317453A (en) * | 1979-02-22 | 1982-03-02 | Dragerwerk Aktiengesellschaft | Method and apparatus for testing a person's breath for the determination of its alcohol content |
US4579826A (en) * | 1983-09-30 | 1986-04-01 | Bolton Craig E | Method and device for analyzing human breath |
US5211181A (en) * | 1991-05-17 | 1993-05-18 | Martek Corporation | Apparatus and method for collecting human breath samples |
US5555890A (en) * | 1992-06-08 | 1996-09-17 | University Of Southern California | Pharyngeal end-tidal carbon dioxide measuring catheter |
EP0650051A2 (en) * | 1993-10-25 | 1995-04-26 | Kyoto Dai-ichi Kagaku Co., Ltd. | Expiration collecting method and automatic expiration collector |
US5573005A (en) * | 1993-10-25 | 1996-11-12 | Kyoto Dai-Ichi Kagaku Co. Ltd. | Expiration collecting method and automatic expiration collector |
EP0650051A3 (en) * | 1993-10-25 | 1997-03-26 | Kyoto Daiichi Kagaku Kk | Expiration collecting method and automatic expiration collector. |
US5687593A (en) * | 1995-06-01 | 1997-11-18 | Hiatt And Company Limited | Handcuffs |
US6248078B1 (en) | 1998-08-31 | 2001-06-19 | Johns Hopkins University | Volatile biomarkers for analysis of hepatic disorders |
US20050000517A1 (en) * | 2000-11-07 | 2005-01-06 | Eriksson Nils Olof | Arrangement in ventilatory treatment of the lungs |
US7828741B2 (en) | 2002-12-20 | 2010-11-09 | The Charlotte-Mecklenburg Hospital Authority | Utilizing lipopolysaccharide in exhaled breath condensate to diagnose gram negative pneumonia |
US20050208614A1 (en) * | 2002-12-20 | 2005-09-22 | The Charlotte-Mecklenburg Hospital Authority | Utilizing lipopolysaccharide in exhaled breath condensate to diagnose gram negative pneumonia |
US8491494B2 (en) | 2002-12-20 | 2013-07-23 | The Charlotte-Mecklenburg Hospital Authority | Disposable hand-held device for collection of exhaled breath condensate |
US20040138577A1 (en) * | 2002-12-20 | 2004-07-15 | Kline Jeffrey A. | Disposable hand-held device for collection of exhaled breath condensate |
US20070203424A1 (en) * | 2002-12-20 | 2007-08-30 | The Charlotte-Mecklenburg Hospital Authority | Disposable hand-held device for collection of exhaled breath condensate |
US20070100250A1 (en) * | 2003-02-14 | 2007-05-03 | The Charlotte-Mecklenburg Hospital Authority | Device and method for collection of exhaled alveolar breath condensate |
US7547285B2 (en) | 2003-02-14 | 2009-06-16 | The Charlotte-Mecklenburg Hospital Authority | Device and method for collection of exhaled alveolar breath condensate |
US20070073183A1 (en) * | 2003-02-14 | 2007-03-29 | The Charlotte-Mecklenburg Hospital Authority | Device and method for collection of exhaled alveolar breath condensate |
US7422723B1 (en) | 2003-10-24 | 2008-09-09 | Alcohol Detection Systems, Inc. | Alcohol breath test device |
US20090044597A1 (en) * | 2005-06-25 | 2009-02-19 | Frank Kvasnik | Breath sampling device |
US7856863B2 (en) * | 2005-06-25 | 2010-12-28 | Sensam Limited | Breath sampling device |
US7779840B2 (en) * | 2006-06-21 | 2010-08-24 | General Electric Company | Ventilator breath condensate sampler and method of collecting a breath condensate sample |
US20080009761A1 (en) * | 2006-06-21 | 2008-01-10 | Acker Jaron M | Ventilator breath condensate sampler and method of collecting a breath condensate sample |
US20090320844A1 (en) * | 2006-08-04 | 2009-12-31 | Nielsen Joergen Groenlund | Method to compensate for the effect of recirculation of inert blood soluble gas on the determination of pulmonary blood flow in repeated inert gas rebreathing tests |
US8201557B2 (en) * | 2006-08-04 | 2012-06-19 | Innovision A/S | Method to compensate for the effect of recirculation of inert blood soluble gas on the determination of pulmonary blood flow in repeated inert gas rebreathing tests |
WO2011064759A1 (en) | 2009-11-30 | 2011-06-03 | Delmedica Investments Limited | Method and device for measurement of exhaled respiratory gas temperature |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: BOURNS MEDICAL SYSTEMS, INC., A CORP. OF CA. Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:BOURNS MEDICAL SYSTEMS, INC., A CORP. OF UTAH;REEL/FRAME:003860/0419 Effective date: 19810519 |
|
AS | Assignment |
Owner name: BEAR MEDICAL SYSTEMS, INC.,, STATELESS Free format text: CHANGE OF NAME;ASSIGNOR:BOURNS MEDICAL SYSTEMS, INC.;REEL/FRAME:003915/0722 Effective date: 19810915 Owner name: BEAR MEDICAL SYSTEMS, INC., Free format text: CHANGE OF NAME;ASSIGNOR:BOURNS MEDICAL SYSTEMS, INC.;REEL/FRAME:003915/0722 Effective date: 19810915 |