US3245067A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Detection of products of combustion
Assignee: B R K ELECTRONICS Inc
•
Filing: 1963-05-24
•
Granted: 1966-04-05
•
Expires: 1983-05-24
Abstract
No abstract record available.
Inventors
- 👤 Lewis G Blevins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:48
CPC Classifications
G; G08; G08B; G08B17/00; G08B17/10; G08B17/11; G08B17/113
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
87 words
AN EARLY WARNING FIRE DETECTOR COMPRISING A DETECTION CHAMBER FREELY OPENED TO AIR FLOW AND A BALANCING CHAMBER HAVING A RESTRICTED ENTRY FOR AIR FLOW, IMPEDANCE MEANS EXPOSED IN EACH OF SAID CHAMBERS SENSITIVE TO THE ELECTRICAL CONDUCTIVITY OF THE AIR IN THE RESPECTIVE CHANMBER, SAID IMPEDANCE MEANS BEING ENERGIZED AT LESS THAN THE IONIZATION POTENTIAL OF AIR AND COMPRISING A BRIDGE SUBJECT TO VARIATION IN POTENTIAL TO PRODUCE A SIGNAL UPON ACESS OF PRODUCTS OF COMBUSTION TO SAID DETECTION CHAMBER AND NOT TO SAID BALANCING CHAMBER.
Claim 2
Dependent Claim
87 words
AN EARLY WARNING FIRE DETECTOR COMPRISING A DETECTION CHAMBER FREELY OPENED TO AIR FLOW AND A BALANCING CHAMBER HAVING A RESTRICTED ENTRY FOR AIR FLOW, IMPEDANCE MEANS EXPOSED IN EACH OF SAID CHAMBERS SENSITIVE TO THE ELECTRICAL CONDUCTIVITY OF THE AIR IN THE RESPECTIVE CHANMBER, SAID IMPEDANCE MEANS BEING ENERGIZED AT LESS THAN THE IONIZATION POTENTIAL OF AIR AND COMPRISING A BRIDGE SUBJECT TO VARIATION IN POTENTIAL TO PRODUCE A SIGNAL UPON ACESS OF PRODUCTS OF COMBUSTION TO SAID DETECTION CHAMBER AND NOT TO SAID BALANCING CHAMBER.
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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) | 1969-04-04 | 1969-10-04 | 1970-04-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-04-04 | 1973-10-04 | 1974-04-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-04-04 | 1977-10-04 | 1978-04-05 | $7700.00 | Window Closed / Lapsed |