Patent US3689394A successfully refreshed from Google Patents.
US3689394A
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US
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Oxygen sensors
Assignee: National Research Development Corp UK
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Filing: 1970-08-11
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Granted: 1972-09-05
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Expires: 1990-08-11
Abstract
Abstract THIS SPECIFICATION DESCRIBES OXYGEN SENSORS WHICH INCLUDE AND ELECTROCHEMICAL CELL HAVING A GAS DIFFUSION ELECTRODE AS CATHOD, A SALT ELECTROLYTE CAPABLE OF BEING MOLTEN AT THE TEMPERATURE OF OPERATION OF THE SENSOR AND A COUNTER ELECTRODE AS ANODE; THE GAS DIFFUSION ELECTRODE INCLUDES A POROUS METAL LAYER AND ANOTHER LAYER SUBSTANTIALLY NONPOROUS TO THE ELECTROLYTE BUT POROUS TO OXYGEN INTERPOSED BETWEEN THE METALLIC LAYER AND THE ENVIRONMENT OF THE SENSOR. WHEN OXYGEN IS PRESENT IN THE ENVIRONMENT THE SENSOR HAS A CURRENT OUTPUT RELATED TO THE OXYGEN CONTENT.
Inventors
- 👤 David Frank Davies
- 👤 Thomas Dickinson
- 👤 Arthur David Foord
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:04
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/403; G01N27/404
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-09-05 | 1976-03-06 | 1976-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-05 | 1980-03-06 | 1980-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-05 | 1984-03-06 | 1984-09-05 | $7700.00 | Window Closed / Lapsed |