US4790925A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrochemical gas sensor
Assignee: MSA Safety Inc
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Filing: 1987-09-18
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Granted: 1988-12-13
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Expires: 2007-09-18
Abstract
Abstract Electrochemical sensor cells having reduced zero current temperature sensitivity comprise a working electrode and a counter electrode in close proximity and in contact with an electrolyte. Both electrodes are exposed to the atmosphere to be tested and at least a portion of the counter electrode is masked from the electrochemically active gas in the atmosphere.
Inventors
- 👤 Barbara C. Miller
- 👤 RaeAnn M. Auel
- 👤 Alan A. Schneider
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:22
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/404; G01N27/4045
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
107 words
A gas sensor for determining an electrochemically active gas in the atmosphere comprising a working electrode and a counter electrode in contact with an electrolyte, the working electrode and counter electrode being bonded in close proximity on one surface of a gas-permeable membrane phobic to the electrolyte, each of said electrodes comprising a catalytic metal, means for exposing the working electrode and the counter electrode to the atmosphere to be tested and masking means for preventing exposure of at least a portion of the counter electrode to the electrochemically active gas, whereby the presence of electrochemically active gas in the atmosphere to be tested produces a current.
Claim 2
Dependent Claim
107 words
A gas sensor for determining an electrochemically active gas in the atmosphere comprising a working electrode and a counter electrode in contact with an electrolyte, the working electrode and counter electrode being bonded in close proximity on one surface of a gas-permeable membrane phobic to the electrolyte, each of said electrodes comprising a catalytic metal, means for exposing the working electrode and the counter electrode to the atmosphere to be tested and masking means for preventing exposure of at least a portion of the counter electrode to the electrochemically active gas, whereby the presence of electrochemically active gas in the atmosphere to be tested produces a current.
Claim 3
Dependent Claim
17 words
A sensor of claim 1 in which the working electrode and counter electrode are of identical composition.
Claim 4
Dependent Claim
29 words
A sensor of claim 2 in which the masking means comprises a gas-impermeable film secured to the opposite surface of the membrane over a portion of the counter electrode.
Claim 5
Dependent Claim
76 words
A sensor of claim 3 in which the masking means comprises a cover means secured to and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, a gas diffusion path through the cover and situated so that the working electrode intercepts substantially all the electrochemically active gas diffusing through said diffusion path.
Claim 6
Dependent Claim
25 words
A sensor of claim 4 in which the working electrode and counter electrode are of identical composition and have equal areas exposed to the atmosphere.
Claim 7
Dependent Claim
15 words
A sensor of claim 5 for measuring carbon monoxide in which the electrodes are platinum.
Claim 8
Dependent Claim
76 words
A sensor of claim 1 in which the masking means comprises a cover means secured to and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, a gas diffusion path through the cover and situated so that the working electrode intercepts substantially all the electrochemically active gas diffusing through said diffusion path.
Claim 9
Dependent Claim
11 words
A sensor of claim 1 in which the electrodes are platinum.
Claim 10
Dependent Claim
50 words
An electrode assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, and a gas-impermeable film secured to the opposite surface of the membrane over a major portion of the counter electrode.
Claim 11
Dependent Claim
50 words
An electrode assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, and a gas-impermeable film secured to the opposite surface of the membrane over a major portion of the counter electrode.
Claim 12
Dependent Claim
100 words
An electrode assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, and a cover means secured to and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, a gas diffusion opening through the cover and aligned with the working electrode so that substantially all the gas diffusing through said diffusion path is exposed to the working electrode.
Claim 13
Dependent Claim
100 words
An electrode assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, and a cover means secured to and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, a gas diffusion opening through the cover and aligned with the working electrode so that substantially all the gas diffusing through said diffusion path is exposed to the working electrode.
Claim 14
Dependent Claim
117 words
An assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, gas impermeable masking means secured to the opposite surface of said membrane, said masking means masking a major portion of the counter electrode and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, and a gas diffusion opening through the cover and aligned with the working electrode so that substantially all the gas diffusing through said diffusion path is exposed to the working electrode.
Claim 15
Dependent Claim
117 words
An assembly for an electrochemical gas sensor comprising a working electrode and a counter electrode of catalytic metal deposited in close proximity on one surface of a gas-permeable membrane, gas impermeable masking means secured to the opposite surface of said membrane, said masking means masking a major portion of the counter electrode and having a portion spaced from the opposite surface of the membrane to form a chamber between the membrane and cover extending over at least a portion of the working electrode and counter electrode, and a gas diffusion opening through the cover and aligned with the working electrode so that substantially all the gas diffusing through said diffusion path is exposed to the working electrode.
Claim 16
Dependent Claim
25 words
An assembly of claim 11 in which the electrodes are of identical composition and the areas of each electrode exposed to the chamber are equal.
Claim 17
Dependent Claim
11 words
An assembly of claim 12 in which the electrodes are platinum.
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) | 1991-12-13 | 1992-06-13 | 1992-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-13 | 1996-06-13 | 1996-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-13 | 2000-06-13 | 2000-12-13 | $7700.00 | Window Closed / Lapsed |