US3593568A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prothrombin time measuring apparatus with means to start the timer in response to the initial decrement of optical transmissivity
Assignee: Roche Diagnostics Corp
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Filing: 1969-04-01
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Granted: 1971-07-20
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Expires: 1989-04-01
Abstract
Abstract A coagulation meter including automatic means for maintaining the test temperature at 37* C. A photocell is used to sense the change in turbidity of the contents of a cuvette. The test is started by the change in voltage output produced by the photocell when the final test component is injected into the cuvette and is ended by the change in photocell voltage output caused by the change in turbidity produced by clotting. The time between these two events is measured by a digital time circuit and display automatically actuated by a differentiation circuit and a detector circuit.
Inventors
- 👤 Lewis E Bovard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:32
CPC Classifications
G; G04; G04F; G04F10/00; G04F10/04; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/4905
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
113 words
Apparatus for coagulation testing comprising a cuvette; means for inserting a test activating component into said cuvette; a photocell; a light source; said photocell, light source and cuvette being so arranged that a change in the characteristics of the contents of said cuvette affects the amount of light delivered to said photocell; a circuit including said photocell; means for differentiating the output of said circuit; means for detecting an output of a given amplitude from said differentiating means; time counting means, and means for automatically starting said time counting means through said photocell and said differentiating means and said detecting means when said inserting means inserts a test activating component into said cuvette.
Claim 2
Dependent Claim
113 words
Apparatus for coagulation testing comprising a cuvette; means for inserting a test activating component into said cuvette; a photocell; a light source; said photocell, light source and cuvette being so arranged that a change in the characteristics of the contents of said cuvette affects the amount of light delivered to said photocell; a circuit including said photocell; means for differentiating the output of said circuit; means for detecting an output of a given amplitude from said differentiating means; time counting means, and means for automatically starting said time counting means through said photocell and said differentiating means and said detecting means when said inserting means inserts a test activating component into said cuvette.
Claim 3
Dependent Claim
133 words
Apparatus for coagulation testing comprising a cuvette; means for inserting a test activating component into said cuvette; a photocell, a light source; said photocell, light source and cuvette being so arranged that a change in the characteristics of the contents of said cuvette affects the amount of light delivered to said photocell; a circuit including said photocell; means for differentiating the output of said circuit; means for detecting an output of a given amplitude from said differentiating means; time counting means; means for automatically starting said time counting means through said differentiating means and said detecting means when said inserting means inserts a test activating component into said cuvette; and means for automatically stopping said time counting means when said differentiating means and said detecting means detect an output of a given amplitude.
Claim 4
Dependent Claim
133 words
Apparatus for coagulation testing comprising a cuvette; means for inserting a test activating component into said cuvette; a photocell, a light source; said photocell, light source and cuvette being so arranged that a change in the characteristics of the contents of said cuvette affects the amount of light delivered to said photocell; a circuit including said photocell; means for differentiating the output of said circuit; means for detecting an output of a given amplitude from said differentiating means; time counting means; means for automatically starting said time counting means through said differentiating means and said detecting means when said inserting means inserts a test activating component into said cuvette; and means for automatically stopping said time counting means when said differentiating means and said detecting means detect an output of a given amplitude.
Claim 5
Dependent Claim
28 words
The apparatus of claim 2 additionally comprising means for preventing said stopping means from operating for a given period of time after said time counting means has started.
Claim 6
Dependent Claim
49 words
The apparatus of claim 2 wherein said starting means includes means for causing said starting means to be operable in response to both negative and positive starting signals of a given amplitude; and means for causing said stopping means to be responsive to a signal of only one polarity.
Claim 7
Dependent Claim
28 words
The apparatus of claim 4 additionally comprising means for preventing said stopping means from operating for a given period of time after said time counting means has started.
Claim 8
Dependent Claim
37 words
The apparatus of claim 5 additionally comprising means for maintaining said cuvette at a temperature of 37* C, and signal means for indicating when the temperature of said cuvette is at a temperature other than 37* C.
Claim 9
Dependent Claim
41 words
The apparatus of claim 5 additionally comprising a display for said time counting means, means for resetting said apparatus after one test in preparation for a further test, and first signal means for indicating when said resetting means is in operation.
Claim 10
Dependent Claim
82 words
The apparatus of claim 7 additionally comprising means for maintaining said cuvette at a temperature of 37* C, and further signal means for indicating when the temperature of said cuvette is at a temperature other than 37* C, said display for said time counting means being lighted, one of said signal means operable to turn at least a portion of said lighted display off and the other of said signal means operable to blink at least a portion of said lighted display.
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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) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |