US3772591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for analyzing blood properties
Assignee: Honeywell International Inc
•
Filing: 1972-04-12
•
Granted: 1973-11-13
•
Expires: 1992-04-12
Abstract
Abstract Method and apparatus for determining the hematocrit and related properties of blood samples by determining the electrical conductance thereof. A sample probe is employed which has two spaced electrodes in the form of capillary tubes on either side of a nonconducting capillary tube. The probe forms an electrical resistivity measuring leg of an A-C bridge circuit and the unbalance of the circuit caused by replacement of a portion of a diluent by the blood sample is measured and transformed into the desired analysis.
Inventors
- 👤 N Louder
- 👤 R Ferrie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:21
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/48; G01N33/483; G01N33/487; G01N33/49
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
104 words
A method of analyzing properties of blood determinable from the electrical conductance thereof comprising drawing a given amount of diluent into a sample probe, the sample probe including two spaced electrodes in the form of capillary tubes positioned at opposing ends of a nonconducting capillary tube and forming one electrical resistivity measuring leg of a balanced bridge circuit, replacing a portion of the diluent between the electrodes with a known amount of blood sample, measuring the unbalance of bridge caused by the replacement of the diluent with the blood, transforming the unbalance in the form of an electrical signal into the desired blood analysis.
Claim 2
Independent Claim
104 words
A method of analyzing properties of blood determinable from the electrical conductance thereof comprising drawing a given amount of diluent into a sample probe, the sample probe including two spaced electrodes in the form of capillary tubes positioned at opposing ends of a nonconducting capillary tube and forming one electrical resistivity measuring leg of a balanced bridge circuit, replacing a portion of the diluent between the electrodes with a known amount of blood sample, measuring the unbalance of bridge caused by the replacement of the diluent with the blood, transforming the unbalance in the form of an electrical signal into the desired blood analysis.
Claim 3
Dependent Claim
27 words
The method of claim 1 including measuring the unbalance of the bridge immediately upon replacing a portion of the diluent with the given amount of blood sample.
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) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |