Patent US5226564A successfully refreshed from Google Patents.
Patent US3674012A successfully refreshed from Google Patents.
← Back to Patent Explorer
US3674012A Expired / Lapsed US ⏱️ 0.0 years remaining

Blood coagulation detection device

Assignee: American Optical Corp
•
Filing: 1970-04-17
•
Granted: 1972-07-04
•
Expires: 1990-04-17
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract This apparatus for detecting the time of coagulation of liquid blood samples includes a hypodermic syringe having the necessary components mounted therein to perform this test. These components include a group of spatially separated electrodes which are disposed around the exterior surface of either the plunger or the base of the barrel where the cannula normally mounts to the hypodermic syringe. Means are provided for connecting the electrodes to an impedance monitoring circuit to ascertain the clotting time of the sample.

Inventors

  • 👤 Stanley J Sage

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:48
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49; G01N33/4905

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 124 words
Apparatus for use with an impedance monitoring circuit for determining the clotting time of a blood sample, the apparatus comprising a hypodermic syringe having a barrel, a plunger, and a cannula for withdrawing and retaining the blood sample from a patient, a plurality of spatially separated electrodes attached to the syringe and engaging the blood sample, the electrodes defining a test cell and at least one control cell, said test cell being defined between a first pair of said plurality of electrodes, said control cell being defined between a second pair of said plurality of electrodes, means associated with the control cells to retard the clotting of the blood sample fraction contained therein, and means for connecting the electrodes to the impedance monitoring circuit.
Claim 2
Dependent Claim 124 words
Apparatus for use with an impedance monitoring circuit for determining the clotting time of a blood sample, the apparatus comprising a hypodermic syringe having a barrel, a plunger, and a cannula for withdrawing and retaining the blood sample from a patient, a plurality of spatially separated electrodes attached to the syringe and engaging the blood sample, the electrodes defining a test cell and at least one control cell, said test cell being defined between a first pair of said plurality of electrodes, said control cell being defined between a second pair of said plurality of electrodes, means associated with the control cells to retard the clotting of the blood sample fraction contained therein, and means for connecting the electrodes to the impedance monitoring circuit.
Claim 3
Dependent Claim 26 words
Apparatus according to claim 1 in which the means for retarding comprises a coating of an anti-coagulating substance disposed on the surface of the control cells.
Claim 4
Dependent Claim 13 words
Apparatus according to claim 2 wherein the anti-coagulating substance is a silicone material.
Claim 5
Dependent Claim 22 words
Apparatus according to claim 2 wherein the anti-coagulating substance is a clot retarding enzyme impregnated into the surface of the control cells.
Claim 6
Dependent Claim 31 words
Apparatus according to claim 1 wherein the means for retarding comprises each of the control cells having a cross-sectional area which is greater than the cross-sectional area of the test cell.
Claim 7
Dependent Claim 41 words
Apparatus according to claim 1 wherein the plurality of spatially separated electrodes are disposed on the plunger adjacent the lower end thereof, and spaced from the interior wall of the barrel so as to define the test anD control cells therebetween.
Claim 8
Dependent Claim 26 words
Apparatus according to claim 6 in which the spatially separated electrodes are a plurality of rings of conductive material disposed around the perimeter of the plunger.
Claim 9
Dependent Claim 12 words
Apparatus according to claim 6 in which the electrodes are point contacts.
Claim 10
Dependent Claim 20 words
Apparatus according to claim 6 which further includes a common conductive bus disposed on the inner wall of the barrel.
Claim 11
Dependent Claim 12 words
Apparatus according to claim 1 in which the hypodermic syringe is disposable.
Claim 12
Dependent Claim 35 words
Apparatus according to claim 1 in which a hollow adapter is mounted between the barrel and the cannula and provides communication therebetween, the test and control cells being disposed between the barrel and the adapter.
Claim 13
Dependent Claim 19 words
Apparatus according to claim 11 in which the syringe is of the permanent type and the adapter is disposable.
Claim 14
Dependent Claim 26 words
Apparatus according to claim 11 wherein the electrodes are conductive bands disposed about the perimeter of the tip of the barrel adjacent to the base thereof.
Claim 15
Dependent Claim 13 words
Apparatus according to claim 10 wherein the electrodes are disposed in the adapter.
Claim 16
Dependent Claim 11 words
Apparatus according to claim 1 wherein one control cell is defined.
Claim 17
Dependent Claim 11 words
Apparatus according to claim 1 wherein three control cells are defined.

References Cited (Backward Citations)

US2555937A Cited
US2637316A Cited
US3000805A Cited
US3078850A Cited
GB950415A Cited
US3224433A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-07-04 1976-01-03 1976-07-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-07-04 1980-01-03 1980-07-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-07-04 1984-01-03 1984-07-04 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag