Patent US2581812A successfully refreshed from Google Patents.
US2581812A
Expired / Lapsed
US
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Flammable gas detector
Assignee: Individual
•
Filing: 1948-10-18
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Granted: 1952-01-08
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Expires: 1968-10-18
Abstract
No abstract record available.
Inventors
- 👤 Carl M Page
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:09
CPC Classifications
G; G01; G01N; G01N25/00; G01N25/20; G01N25/22; G01N25/28; G01N25/30; G01N25/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
104 words
IN INDICATORS FOR COMBUSTIBLE GAS HAVING A CATALYST FOR THE COMBUSTION AND ELECTRICAL HEATING MEANS DISPOSED ADJACENT THE CATALYST TO HEAT THE CATALYST AND ACTIVATE IT, THE COMBINATION WHICH COMPRISES A THERMOCOUPLE HAVING ONE JUNCTION ADJACENT THE CATALYST AND ITS OTHER JUNCTION REMOTE THEREFROM, CURRENT INDICATING MEANS CONNECTED TO THE THERMOCOUPLE, A CIRCUIT FOR SUPPLYING HEATING CURRENT TO THE ELECTRICAL MEANS, A RESISTOR IN SAID CIRCUIT ADAPTED TO PASS A SMALL AMOUNT OF CURRENT SUBSTANTIALLY CONTINUOUSLY TO THE HEATING MEANS, AND A SWITCH OPERATED BY-PASS OF THE RESISTOR IN THE CIRCUIT TO SUPPLY ADDITIONAL CURRENT TO THE HEATING MEANS WHEN THE SWITCH IS CLOSED.
Claim 2
Dependent Claim
104 words
IN INDICATORS FOR COMBUSTIBLE GAS HAVING A CATALYST FOR THE COMBUSTION AND ELECTRICAL HEATING MEANS DISPOSED ADJACENT THE CATALYST TO HEAT THE CATALYST AND ACTIVATE IT, THE COMBINATION WHICH COMPRISES A THERMOCOUPLE HAVING ONE JUNCTION ADJACENT THE CATALYST AND ITS OTHER JUNCTION REMOTE THEREFROM, CURRENT INDICATING MEANS CONNECTED TO THE THERMOCOUPLE, A CIRCUIT FOR SUPPLYING HEATING CURRENT TO THE ELECTRICAL MEANS, A RESISTOR IN SAID CIRCUIT ADAPTED TO PASS A SMALL AMOUNT OF CURRENT SUBSTANTIALLY CONTINUOUSLY TO THE HEATING MEANS, AND A SWITCH OPERATED BY-PASS OF THE RESISTOR IN THE CIRCUIT TO SUPPLY ADDITIONAL CURRENT TO THE HEATING MEANS WHEN THE SWITCH IS CLOSED.
References Cited (Backward Citations)
US1321063A
Cited
US1779569A
Cited
US1880941A
Cited
US2219391A
Cited
GB521098A
Cited
US2234128A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1955-01-07 | 1955-07-09 | 1956-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-01-07 | 1959-07-09 | 1960-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-01-07 | 1963-07-09 | 1964-01-08 | $7700.00 | Window Closed / Lapsed |