Patent US3305852A successfully refreshed from Google Patents.
US3305852A
Expired / Lapsed
US
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Cumulative detector for chlorine gas
Assignee: Dow Chemical Co
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Filing: 1963-12-09
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Granted: 1967-02-21
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Expires: 1983-12-09
Abstract
No abstract record available.
Inventors
- 👤 Jr Jerome C Cates
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:46
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/75; G01N21/77; G01N21/78; G01N21/783
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
119 words
IN PHOTO-ELECTRIC APPARATUS FOR DETECTING THE PRESENCE OF CHLORINE GAS, SAID APPARATUS COMPRISING A LIGHT SOURCE, MEANS FOR DIRECTING LIGHT FROM SAID SOURCE ONTO A FIXEDLY DISPOSED SURFACE OF A SILVER MIRROR, A PHOTOCELL SO-DISPOSED WITH RESPECT TO SAID LIGHT SOURCE AND SAID SILVER MIRROR THAT LIGHT FROM SAID SOURCE IS REFLECTED FROM SAID SURFACE ONTO SAID PHOTOCELL, A LIGHT TIGHT ENCLOSURE, SAID LIGHT SOURCE, SILVER MIRROR AND PHOTOCELL BEING DISPOSED IN SAID ENCLOSURE, AND MEANS ACTUATED BY SAID PHOTOCELL FOR PROVIDING A SIGNAL ON A PREDETERMINED CHANGE IN LIGHT INTENSITY IMPINGING ON SAID CELL, THE IMPROVEMENT WHEREIN SAID EXPOSED SURFACE OF SAID SILVER MIRROR UNDERGOES A PHYSICAL CHANGE IN LIGHT REFLECTIVE PROPERTIES ON EXPOSURE TO SAID CHLORINE GAS.
Claim 2
Dependent Claim
119 words
IN PHOTO-ELECTRIC APPARATUS FOR DETECTING THE PRESENCE OF CHLORINE GAS, SAID APPARATUS COMPRISING A LIGHT SOURCE, MEANS FOR DIRECTING LIGHT FROM SAID SOURCE ONTO A FIXEDLY DISPOSED SURFACE OF A SILVER MIRROR, A PHOTOCELL SO-DISPOSED WITH RESPECT TO SAID LIGHT SOURCE AND SAID SILVER MIRROR THAT LIGHT FROM SAID SOURCE IS REFLECTED FROM SAID SURFACE ONTO SAID PHOTOCELL, A LIGHT TIGHT ENCLOSURE, SAID LIGHT SOURCE, SILVER MIRROR AND PHOTOCELL BEING DISPOSED IN SAID ENCLOSURE, AND MEANS ACTUATED BY SAID PHOTOCELL FOR PROVIDING A SIGNAL ON A PREDETERMINED CHANGE IN LIGHT INTENSITY IMPINGING ON SAID CELL, THE IMPROVEMENT WHEREIN SAID EXPOSED SURFACE OF SAID SILVER MIRROR UNDERGOES A PHYSICAL CHANGE IN LIGHT REFLECTIVE PROPERTIES ON EXPOSURE TO SAID CHLORINE GAS.
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) | 1970-02-20 | 1970-08-22 | 1971-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-02-20 | 1974-08-22 | 1975-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-02-20 | 1978-08-22 | 1979-02-21 | $7700.00 | Window Closed / Lapsed |