Patent FR2372287A1 successfully refreshed from Google Patents.
US3307392A
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Automatic prothrombin timer apparatus and method
Assignee: Research Corp
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Filing: 1964-05-04
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Granted: 1967-03-07
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Expires: 1984-05-04
Abstract
No abstract record available.
Inventors
- 👤 Charles A Owen
- 👤 Isaacson James
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:02
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/4905; G01N21/00; G01N21/17; G01N21/25; G01N21/27; G01N21/272
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
82 words
THE METHOD OF MEASURING THE PROTHROMBIN TIME OF BLOOD PLASMA WHICH COMPRISES MIXING A SAMPLE OF PLASMA WITH A CLOTTING AGENT, PASSING LIGHT THROUGH THE SAMPLE AS IT CLOTS, GENERATING A PRIMARY SIGNAL PROPORTIONAL TO THE TRANSMITTED LIGHT, OBTAINING A SECONDARY SIGNAL FROM THE PRIMARY SIGNAL, SAID SECONDARY SIGNAL BEING THE FIRST DERIVATIVE OF THE PRIMARY SIGNAL AND MEASURING THE TIME PERIOD FOR CLOTTING OF TH EPLASMA SAMPLE ENDING WHEN SAID SECONDARY SIGNAL BEGINS TO CHANGE AFTER HAVING REACHED A STEADY VALUE.
Claim 2
Independent Claim
82 words
THE METHOD OF MEASURING THE PROTHROMBIN TIME OF BLOOD PLASMA WHICH COMPRISES MIXING A SAMPLE OF PLASMA WITH A CLOTTING AGENT, PASSING LIGHT THROUGH THE SAMPLE AS IT CLOTS, GENERATING A PRIMARY SIGNAL PROPORTIONAL TO THE TRANSMITTED LIGHT, OBTAINING A SECONDARY SIGNAL FROM THE PRIMARY SIGNAL, SAID SECONDARY SIGNAL BEING THE FIRST DERIVATIVE OF THE PRIMARY SIGNAL AND MEASURING THE TIME PERIOD FOR CLOTTING OF TH EPLASMA SAMPLE ENDING WHEN SAID SECONDARY SIGNAL BEGINS TO CHANGE AFTER HAVING REACHED A STEADY VALUE.
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) | 1970-03-06 | 1970-09-05 | 1971-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-06 | 1974-09-05 | 1975-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-06 | 1978-09-05 | 1979-03-07 | $7700.00 | Window Closed / Lapsed |