Patent US4145913A successfully refreshed from Google Patents.
US4145913A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas detectors
Assignee: National Research Development Corp UK
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Filing: 1977-02-25
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Granted: 1979-03-27
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Expires: 1997-02-25
Abstract
Abstract Apparatus for determining the concentration of a component of a gaseous mixture by selective absorption of the component in a liquid absorbent and measurement of a property of the absorbent, such as the electrical conductivity, related to the concentration of the component therein, comprising an absorption cell for containing the liquid absorbent; means for bringing a stream of said gaseous mixture into contact with the absorbent; means for flushing the absorption cell with absorbent from a reservoir so as to recharge the cell with absorbent; and means for providing a first signal related to said property of the absorbent immediately after flushing the cell, for providing a second signal related to the property after a predetermined time, and for providing a third signal related to the difference between the second and first signals.
Inventors
- 👤 Cyril Brown
- 👤 Christopher J. Derrett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:47
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/4162; G01N33/00; G01N33/0004; G01N33/0009; G01N33/0027; G01N33/0036; G01N33/0042
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
154 words
Apparatus for determining the concentration of a component of a gaseous mixture by selective absorption of the component in a liquid absorbent and measurement of a property of the absorbent related to the concentration of the component therein, the apparatus comprising an absorption cell for containing the liquid absorbent; means for bringing a stream of said gaseous mixture into contact with the absorbent; means for flushing the absorbent cell at regular intervals of time with absorbent from a reservoir so as to recharge the cell with absorbent; means for returning the absorbent flushed from the cell to the reservoir; and means for providing a first signal related to said property of the absorbent immediately after flushing the cell, for providing a second signal related to said property immediately before flushing the cell in the next interval of time, and for providing a third signal related to the difference between the second and first signals.
Claim 2
Dependent Claim
154 words
Apparatus for determining the concentration of a component of a gaseous mixture by selective absorption of the component in a liquid absorbent and measurement of a property of the absorbent related to the concentration of the component therein, the apparatus comprising an absorption cell for containing the liquid absorbent; means for bringing a stream of said gaseous mixture into contact with the absorbent; means for flushing the absorbent cell at regular intervals of time with absorbent from a reservoir so as to recharge the cell with absorbent; means for returning the absorbent flushed from the cell to the reservoir; and means for providing a first signal related to said property of the absorbent immediately after flushing the cell, for providing a second signal related to said property immediately before flushing the cell in the next interval of time, and for providing a third signal related to the difference between the second and first signals.
Claim 3
Dependent Claim
42 words
Apparatus according to claim 1 in which the means for bringing a stream of the gaseous mixture into contact with the absorbent comprises a jet-forming means arranged to direct a jet of the gaseous mixture on to the surface of the absorbent.
Claim 4
Dependent Claim
24 words
Apparatus according to claim 1 in which the property of the absorbent related to the concentration of the component therein is the electrical conductivity.
Claim 5
Dependent Claim
32 words
Apparatus according to claim 1 further comprising temperature sensitive means arranged to sense the temperature of the absorbent and to compensate the first and second signals in accordance with the sensed temperature.
Claim 6
Independent Claim
135 words
A method of determining the concentration of a component of a gaseous mixture by selective absorption of the component in a liquid absorbent and measurement of a property of the absorbent related to the concentration of the component therein, comprising bringing a stream of gaseous mixture into contact with a quantity of said absorbent in an absorption cell; flushing the absorption cell with absorbent from a reservoir so as to recharge the cell with absorbent; returning the absorbent flushed from the cell to the reservoir; providing a first signal related to said property of the absorbent immediately after flushing the cell, providing a second signal related to the property immediately before flushing the cell in the next interval of time, and providing a third signal related to the difference between the second and first signals.
Claim 7
Independent Claim
135 words
A method of determining the concentration of a component of a gaseous mixture by selective absorption of the component in a liquid absorbent and measurement of a property of the absorbent related to the concentration of the component therein, comprising bringing a stream of gaseous mixture into contact with a quantity of said absorbent in an absorption cell; flushing the absorption cell with absorbent from a reservoir so as to recharge the cell with absorbent; returning the absorbent flushed from the cell to the reservoir; providing a first signal related to said property of the absorbent immediately after flushing the cell, providing a second signal related to the property immediately before flushing the cell in the next interval of time, and providing a third signal related to the difference between the second and first signals.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-26 | 1982-09-25 | 1983-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-26 | 1986-09-25 | 1987-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-26 | 1990-09-25 | 1991-03-27 | $7700.00 | Window Closed / Lapsed |