US4419903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for detecting insufficient liquid levels
Assignee: Beckman Coulter Inc
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Filing: 1982-02-22
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Granted: 1983-12-13
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Expires: 2002-02-22
Abstract
Abstract A method and apparatus for determining an insufficient liquid volume. The invention includes an electromagnetic sensing device in a conduit into which the sample liquid is mixed. The electromagnetic sensing device detects the presence of air in the conduit which indicates that an insufficient liquid volume has been aspirated.
Inventors
- 👤 Delbert D. Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:38
CPC Classifications
G; G01; G01N; G01N35/00; G01N35/08
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
96 words
In a liquid sampling apparatus including a probe for withdrawing a first liquid volume from a container, a conduit into which said liquid volume may be expelled, and a source of a second liquid volume connected to said conduit, said second liquid volume to be mixed with said first liquid volume thereby generating air bubbles if said liquid volumes are insufficient; a device for detecting said insufficient volumes comprising: electromagnetic means, associated with said conduit, for detecting the presence of said air bubbles; and means, responsive to said detecting means, for counting said detected air bubbles.
Claim 2
Dependent Claim
96 words
In a liquid sampling apparatus including a probe for withdrawing a first liquid volume from a container, a conduit into which said liquid volume may be expelled, and a source of a second liquid volume connected to said conduit, said second liquid volume to be mixed with said first liquid volume thereby generating air bubbles if said liquid volumes are insufficient; a device for detecting said insufficient volumes comprising: electromagnetic means, associated with said conduit, for detecting the presence of said air bubbles; and means, responsive to said detecting means, for counting said detected air bubbles.
Claim 3
Dependent Claim
29 words
Apparatus according to claim 1 wherein said electromagnetic means includes: a light source; and a light detector located on the same side of said conduit as said light source.
Claim 4
Dependent Claim
29 words
Apparatus according to claim 1 wherein said electromagnetic means includes: a light source; and a light detector located on the opposite side of said conduit from said light source.
Claim 5
Independent Claim
76 words
A method for determining an insufficient liquid volume in a liquid sampling apparatus comprising the steps of: aspirating a volume of a first liquid from a container; mixing said aspirated volume with a second liquid volume thereby generating air bubbles if said liquid volumes are insufficient; conducting said mixed first and second liquids and said air bubbles through a conduit; electromagnetically detecting the presence of said air bubbles in said conduit; and counting said air bubbles.
Claim 6
Independent Claim
76 words
A method for determining an insufficient liquid volume in a liquid sampling apparatus comprising the steps of: aspirating a volume of a first liquid from a container; mixing said aspirated volume with a second liquid volume thereby generating air bubbles if said liquid volumes are insufficient; conducting said mixed first and second liquids and said air bubbles through a conduit; electromagnetically detecting the presence of said air bubbles in said conduit; and counting said air bubbles.
References Cited (Backward Citations)
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Cited
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Cited
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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) | 1986-12-12 | 1987-06-13 | 1987-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-12 | 1991-06-13 | 1991-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-12 | 1995-06-13 | 1995-12-13 | $7700.00 | Window Closed / Lapsed |