US4374620A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photometric flow cell
Assignee: ALTEX SCIENTIFIC Inc A CORP OF DE
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Filing: 1981-01-29
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Granted: 1983-02-22
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Expires: 2001-01-29
Abstract
Abstract A photometric flow cell for high pressure liquid chromatography having an illuminated passageway therein between open ends of which fluid samples are flowed for analysis. An annular, porous flow impedance element is supported in an annular channel surrounding one end of the passageway. The impedance element reduces turbulence of flow through the open end by evenly distributing the flowing fluid circumferentially about the end opening.
Inventors
- 👤 Alan C. Berick
- 👤 Haakon T. Magnussen, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 12:15
CPC Classifications
G; G01; G01N; G01N30/00; G01N30/02; G01N30/62; G01N30/74; G01N21/00; G01N21/01; G01N21/03; G01N21/05; G01N2021/0346
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
80 words
A photometric flow cell comprising: a flow cell body having a passageway for receiving and passing fluid samples between opposite ends thereof; optically transparent windows at said opposite ends of said passageway for passing light along an optical path through sample in said passageway; an annular channel around one of said opposite ends of said passageway; and flow impedance means including a microporous annulus in said channel surrounding said one of said opposite ends for circumferentially distributing fluid flowing therethrough.
Claim 2
Dependent Claim
80 words
A photometric flow cell comprising: a flow cell body having a passageway for receiving and passing fluid samples between opposite ends thereof; optically transparent windows at said opposite ends of said passageway for passing light along an optical path through sample in said passageway; an annular channel around one of said opposite ends of said passageway; and flow impedance means including a microporous annulus in said channel surrounding said one of said opposite ends for circumferentially distributing fluid flowing therethrough.
Claim 3
Dependent Claim
23 words
The flow cell of claim 1 including means for flowing said fluid samples into said passageway through said one of said opposite ends.
Claim 4
Dependent Claim
24 words
The flow cell of claim 1 including means for flowing said fluid samples out of said passageway through said one of said opposite ends.
Claim 5
Dependent Claim
26 words
The flow cell of claim 1 wherein said annular channel and said flow impedance means are provided at each of said opposite ends of said passageway.
Claim 6
Dependent Claim
22 words
The flow cell of claim 1 or 4 wherein said microporous annulus has a pore size in the range of about 2.0-10μ.
Claim 7
Dependent Claim
12 words
The flow cell of claim 5 wherein said microporous annulus comprises metal.
Claim 8
Dependent Claim
12 words
The flow cell of claim 5 wherein said microporous annulus comprises plastic.
Claim 9
Dependent Claim
65 words
In combination: a flow cell body having a passageway for receiving and passing fluid samples between opposite ends thereof; means for measuring a characteristic of fluid sample while in the passageway; and fluid flow impedance means including a microporous annulus surrounding one of said opposite ends of said passageway for circumferentially distributing fluid flowing therethrough about the circumference of said one of said opposite ends.
Claim 10
Dependent Claim
65 words
In combination: a flow cell body having a passageway for receiving and passing fluid samples between opposite ends thereof; means for measuring a characteristic of fluid sample while in the passageway; and fluid flow impedance means including a microporous annulus surrounding one of said opposite ends of said passageway for circumferentially distributing fluid flowing therethrough about the circumference of said one of said opposite ends.
Claim 11
Dependent Claim
22 words
The combination of claim 7 wherein said characteristic is measured by said measuring means as said fluid sample passes along said passageway.
Claim 12
Dependent Claim
21 words
The combination of claim 8, wherein said flow impedance means are provided at each of said opposite ends of said passageway.
Claim 13
Dependent Claim
21 words
The combination of claim 8 or 10 wherein said microporous annulus has a pore size in the range of about 2.0-10.0μ.
Claim 14
Dependent Claim
12 words
The flow cell of claim 11 wherein said microporous annulus comprises metal.
Claim 15
Dependent Claim
12 words
The flow cell of claim 11 wherein said microporous annulus comprises plastic.
References Cited (Backward Citations)
CH458794A
Cited
US3515491A
Cited
US3647304A
Cited
DE2158220A1
Cited
DE2246225A1
Cited
GB2001752A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-21 | 1986-08-23 | 1987-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-21 | 1990-08-23 | 1991-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-21 | 1994-08-23 | 1995-02-22 | $7700.00 | Window Closed / Lapsed |