US5117674A
Expired / Lapsed
US
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Metabolic rate analyzer
Assignee: Aerosport Inc
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Filing: 1991-08-29
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Granted: 1992-06-02
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Expires: 2011-08-29
Abstract
Abstract The metabolic rate analyzer comprises a flow proportioning valve for producing a proportional sample of the expired gas of the subject being studied. A sample cylinder is provided for drawing a proportional sample of the expired gas of the subject being studied from the flow proportioning valve. A test chamber is provided and an O 2 sensor is provided. The test chamber is provided with a selectively-permeable membrane, the selectively-permeable membrane having a selective permeability for CO 2 , whereby CO 2 is selectively vented from the test chamber. The sample cylinder is also used for charging the test chamber with the proportional sample of the expired gas of the subject. A pressure sensor is provided for monitoring the pressure of the sample and determining the rate of pressure decay in the test chamber due to the selective venting of CO 2 through the permeable membrane. An analyzing means is provided for determining CO 2 content in the expired gas from the rate of pressure decay in the test chamber, conducting a volumetric analysis of the proportioinal sample to determine total volume of expired gas, and then correlating O 2 content, CO 2 content and total volume of expired gas to provide a measure of the metabolic rate of the subject being studied.
Inventors
- 👤 Charles P. Howard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:34
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/02; A61B5/0205; A61B5/02055; A61B5/08; A61B5/083; A61B5/087; G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/497
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
113 words
A CO 2 gas analyzer comprising: a test chamber; a means for charging said test chamber with a sample gas; a selectively-permeable membrane disposed in said test chamber, said membrane being provided with a selective permeability for CO 2 , said membrane being disposed in said test chamber for selectively venting CO 2 from said test chamber; a pressure sensor for monitoring the pressure of the sample and determining the rate of pressure decay in said test chamber due to selective venting of CO 2 through said selectively-permeable membrane; and an analyzing means for determining the CO 2 content of the sample gas from the rate of pressure decay in said test chamber.
Claim 2
Dependent Claim
113 words
A CO 2 gas analyzer comprising: a test chamber; a means for charging said test chamber with a sample gas; a selectively-permeable membrane disposed in said test chamber, said membrane being provided with a selective permeability for CO 2 , said membrane being disposed in said test chamber for selectively venting CO 2 from said test chamber; a pressure sensor for monitoring the pressure of the sample and determining the rate of pressure decay in said test chamber due to selective venting of CO 2 through said selectively-permeable membrane; and an analyzing means for determining the CO 2 content of the sample gas from the rate of pressure decay in said test chamber.
Claim 3
Dependent Claim
32 words
The CO 2 gas analyzer of claim 1 further comprising a temperature sensor for monitoring the temperature of the sample, and analyzing means for determining CO 2 content corrected for sample temperature.
Claim 4
Dependent Claim
146 words
The CO 2 gas analyzer of claim 1 further comprising: a second gas test chamber; a second membrane disposed in said second gas test chamber, said second gas membrane being provided with a permeability for a second gas, said second membrane being disposed in said second gas test chamber for selectively venting a second gas from said second gas test chamber; a means for charging said second gas test chamber with a sample gas; a second gas pressure sensor for monitoring the pressure of the sample in said second gas test chamber and determining the rate of pressure decay in said second gas test chamber due to the selective venting of a second gas through said second gas membrane; and an analyzing means for determining the content of a second gas in the sample from the rate of pressure decay in said second gas test chamber.
Claim 5
Dependent Claim
59 words
The CO 2 gas analyzer of claim 3 wherein said second membrane is similar in composition to said membrane having a selective permeability for CO 2 and each of said first and second test chambers are provided with a reference gas, and the reference gas in the first chamber is different than the reference gas in the second chamber.
Claim 6
Dependent Claim
28 words
The CO 2 gas analyzer of claim 4 wherein a reference gas of ambient air is provided for said membrane having a selective permeability for CO 2 .
Claim 7
Dependent Claim
25 words
The CO 2 gas analyzer of claim 5 wherein a reference gas comprising a sample of the second gas is provided for said second membrane.
Claim 8
Dependent Claim
65 words
The CO 2 gas analyzer of claim 1 wherein said test chamber comprises a pressure vessel; a sample outlet; a sample inlet; a sample window; a first porous sintered metal plate disposed in said sample window; a second porous sintered metal plate disposed in said sample window, said selectively-permeable membrane being disposed between said first and second sintered metal plates and supported by the same.
Claim 9
Dependent Claim
17 words
The CO 2 gas analyzer of claim 1 wherein said selectively-permeable membrane comprises a silicone rubber membrane.
Claim 10
Dependent Claim
46 words
The CO 2 gas analyzer of claim 8 further comprising a well disposed adjacent said selectively-permeable membrane, said well being disposed outside of said test chamber, said well containing a matrix saturated with water to compensate for the presence of water vapor in the sample gas.
Claim 11
Dependent Claim
32 words
The CO 2 gas analyzer of claim 1 wherein said analyzing means further comprises an analog to digital converter for transforming an analog signal representative of pressure into a corresponding digital signal.
Claim 12
Dependent Claim
37 words
The CO 2 gas analyzer of claim 10 wherein said analyzing means further comprises a programmed digital processor for determining the rate of pressure decay and then correlating the same to a value for CO 2 content.
Claim 13
Dependent Claim
134 words
A gas analyzer comprising: a first test chamber; a means for charging said test chamber with a sample gas; a first selectively-permeable membrane disposed in said first test chamber, said first membrane being provided with a selective permeability for a first gas of interest, said first membrane being disposed in said first test chamber for selectively venting the first gas of interest from said first test chamber; a first pressure sensor for monitoring the pressure of the sample and determining the rate of pressure decay in said first test chamber due to selective venting of the first gas of interest through said first selectively-permeable membrane; and an analyzing means for determining the concentration of the first gas of interest in the sample gas from the rate of pressure decay in said first test chamber.
Claim 14
Dependent Claim
134 words
A gas analyzer comprising: a first test chamber; a means for charging said test chamber with a sample gas; a first selectively-permeable membrane disposed in said first test chamber, said first membrane being provided with a selective permeability for a first gas of interest, said first membrane being disposed in said first test chamber for selectively venting the first gas of interest from said first test chamber; a first pressure sensor for monitoring the pressure of the sample and determining the rate of pressure decay in said first test chamber due to selective venting of the first gas of interest through said first selectively-permeable membrane; and an analyzing means for determining the concentration of the first gas of interest in the sample gas from the rate of pressure decay in said first test chamber.
Claim 15
Dependent Claim
35 words
The gas analyzer of claim 12 further comprising a temperature sensor for monitoring the temperature of the sample, and analyzing means for determining the concentration of the first gas of interest corrected for sample temperature.
Claim 16
Dependent Claim
143 words
The gas analyzer of claim 12 further comprising: a second gas test chamber; a second membrane disposed in said second gas test chamber, said second membrane being provided with a selective permeability for a second gas, said second membrane being disposed in said second gas test chamber for selectively venting a second gas from said second gas test chamber; a means for charging said second gas test chamber with a sample gas; a second gas pressure sensor for monitoring the pressure of the sample in said second gas test chamber and determining the rate of pressure decay in said second gas test chamber due to the selective venting of a second gas through said second membrane; and an analyzing means for determining the concentration of a second gas in the sample from the rate of pressure decay in said second gas test chamber.
Claim 17
Dependent Claim
18 words
The gas analyzer of claim 14 wherein said second membrane is similar in composition to said first membrane.
Claim 18
Dependent Claim
34 words
The gas analyzer of claim 15 wherein a first reference gas is provided for said first membrane and a second reference gas different from said first reference gas is provided for said second membrane.
Claim 19
Dependent Claim
14 words
The gas analyzer of claim 16 wherein said first reference gas comprises ambient air.
Claim 20
Dependent Claim
18 words
The gas analyzer of claim 17 wherein said second reference gas comprises a sample of the second gas.
Claim 21
Dependent Claim
65 words
The gas analyzer of claim 12 wherein said first test chamber comprises a pressure vessel; a sample outlet; a sample inlet; a sample window; a first porous sintered metal plate disposed in said sample window; a second porous sintered metal plate disposed in said sample window, said first selectively-permeable membrane being disposed between said first and second sintered metal plates and supported by the same.
Claim 22
Dependent Claim
16 words
The gas analyzer of claim 12 wherein said first selectively-permeable membrane comprises a silicone rubber membrane.
Claim 23
Dependent Claim
46 words
The gas analyzer of claim 20 further comprising a well disposed adjacent said first selectively-permeable membrane, said well being disposed outside of said first test chamber, said well containing a matrix saturated with water to compensate for the presence of water vapor in the sample gas.
Claim 24
Dependent Claim
29 words
The gas analyzer of claim 12 wherein said analyzing means further comprises an analog to digital converter for transforming an analog signal representative of pressure into corresponding digital signals.
Claim 25
Dependent Claim
39 words
The gas analyzer of claim 22 wherein said analyzing means further comprises a programmed digital processor for determining the rate of pressure decay and then correlating the same to a value for the concentration of the gas of interest.
Claim 26
Independent Claim
122 words
A method for determining CO 2 concentration in a gas mixture comprising the steps of: providing a test chamber; providing the test chamber with a pressure sensor and a selectively-permeable membrane, the membrane being provided with a selective permeability for CO 2 , the membrane being disposed in the chamber for selectively venting CO 2 from the test chamber; charging the test chamber with a sample of the gas mixture; monitoring the pressure of the sample in the test chamber; determining the rate of pressure decay in the test chamber due to the selective venting of CO 2 through the selectively-permeable membrane; and determining the CO 2 concentration in the gas mixture from the rate of pressure decay in the test chamber.
Claim 27
Independent Claim
122 words
A method for determining CO 2 concentration in a gas mixture comprising the steps of: providing a test chamber; providing the test chamber with a pressure sensor and a selectively-permeable membrane, the membrane being provided with a selective permeability for CO 2 , the membrane being disposed in the chamber for selectively venting CO 2 from the test chamber; charging the test chamber with a sample of the gas mixture; monitoring the pressure of the sample in the test chamber; determining the rate of pressure decay in the test chamber due to the selective venting of CO 2 through the selectively-permeable membrane; and determining the CO 2 concentration in the gas mixture from the rate of pressure decay in the test chamber.
Claim 28
Dependent Claim
117 words
The method for determining CO 2 concentration of claim 24 further comprising the steps of: providing a second gas test chamber with a second gas pressure sensor and a second membrane having a permeability for a second gas of interest; charging the second gas test chamber with a sample of the gas mixture; monitoring the pressure of the sample in the second gas test chamber; determining the rate of pressure decay in the second gas test chamber due to selective venting of the second gas of interest through the second membrane; and determining the concentration of the second gas of interest in the gas mixture from the rate of pressure decay in the second gas test chamber.
Claim 29
Dependent Claim
28 words
The method for determining CO 2 concentration of claim 25 further comprising the steps of: providing membranes of similar composition; and providing different reference gases for each membrane.
Claim 30
Dependent Claim
44 words
The method for determining CO 2 concentration of claim 25 further comprising the steps of: providing an ambient air reference for the membrane having a selective permeability for CO 2 ; and providing a sample of the second gas reference for the second membrane.
Claim 31
Dependent Claim
46 words
The method for determining CO 2 concentration of claim 24 further comprising the steps of: providing a temperature sensor; monitoring the temperature of the sample gas; and temperature correcting the steps of monitoring pressure, determining the rate of pressure decay and determining the CO 2 concentration.
Claim 32
Dependent Claim
41 words
The method for determining CO 2 concentration of claim 24 further comprising the steps of: forming a selectively-permeable membrane from silicone rubber; and compensating for water vapor in the sample by saturating the outside surface of the silicone membrane with water.
Claim 33
Independent Claim
138 words
A method of gas analysis comprising the steps of: providing a first test chamber; providing the first test chamber with a first pressure sensor and a first selectively-permeable membrane, the first membrane having a selective permeability for a first gas of interest, the first membrane being disposed in the first test chamber for selectively venting the first gas of interest from the test chamber; charging the first test chamber with a sample of a gas mixture; monitoring the pressure of the sample in the first test chamber; determining the rate of pressure decay in the first test chamber due to the selective venting of the first as of interest through the first selectively-permeable membrane; and determining the concentration of the first gas of interest in the gas mixture from the rate of pressure decay in the test chamber.
Claim 34
Independent Claim
138 words
A method of gas analysis comprising the steps of: providing a first test chamber; providing the first test chamber with a first pressure sensor and a first selectively-permeable membrane, the first membrane having a selective permeability for a first gas of interest, the first membrane being disposed in the first test chamber for selectively venting the first gas of interest from the test chamber; charging the first test chamber with a sample of a gas mixture; monitoring the pressure of the sample in the first test chamber; determining the rate of pressure decay in the first test chamber due to the selective venting of the first as of interest through the first selectively-permeable membrane; and determining the concentration of the first gas of interest in the gas mixture from the rate of pressure decay in the test chamber.
Claim 35
Dependent Claim
115 words
The method of gas analysis of claim 30 further comprising the steps of: providing a second gas test chamber with a second gas pressure sensor and a second membrane having a permeability for a second gas of interest; charging the second gas test chamber with a sample of the gas mixture; monitoring the pressure of the sample in the second gas test chamber; determining the rate of pressure decay in the second gas test chamber due to selective venting of the second gas of interest through the second membrane; and determining the concentration of the second gas of interest in the gas mixture from the rate of pressure decay in the second gas test chamber.
Claim 36
Dependent Claim
30 words
The method of gas analysis of claim 31 further comprising the steps of: providing first and second membranes having a similar composition; and providing different reference gases for each membrane.
Claim 37
Dependent Claim
35 words
The method of gas analysis of claim 31 further comprising the steps of: providing an ambient air reference for the first membrane; and providing a sample of the second gas reference for the second membrane.
Claim 38
Dependent Claim
46 words
The method of gas analysis of claim 30 further comprising the steps of: providing a temperature sensor; monitoring the temperature of the sample gas; and temperature correcting the steps of monitoring pressure, determining the rate of pressure decay and determining the concentration of gas of interest.
Claim 39
Dependent Claim
39 words
The method of gas analysis of claim 30 further comprising the steps of: forming a selectively-permeable membrane from silicone rubber; and compensating for water vapor in the sample by saturating the outside surface of the silicone membrane with water.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-06-02 | 1995-12-02 | 1996-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-06-02 | 1999-12-02 | 2000-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-06-02 | 2003-12-02 | 2004-06-02 | $7700.00 | Window Closed / Lapsed |