Patent US4285809A successfully refreshed from Google Patents.
US4285809A
Expired / Lapsed
US
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Rotor for sedimentation field flow fractionation
Assignee: EIDP Inc
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Filing: 1980-02-29
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Granted: 1981-08-25
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Expires: 2000-02-29
Abstract
Abstract A long, thin annular belt-like channel is designed for use in sedimentation field flow fractionation. The channel has a generally rectangular cross section and a width to thickness aspect ratio lying in the range of 3-50 to 1. The channel may be formed of a flattened capillary tube. The ratio of the thickness of the channel to the characteristic height of the particles to be separated is greater than 5 to 1.
Inventors
- 👤 Charles H. Dilks, Jr.
- 👤 Joseph J. Kirkland
- 👤 Wallace W. Yau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:08
CPC Classifications
B; B04; B04B; B04B5/00; B04B5/04; B04B5/0442; B03; B03B; B03B5/00; B04B2005/045
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
97 words
An apparatus for separating particulates suspended in a fluid medium according to their effective masses, said apparatus having an annular cylindrical channel with a cylinder axis, said channel being sufficiently thin in the radial dimension to effect laminar flow therein, means for rotating said channel about said axis, means for passing said fluid medium circumferentially through said channel, and means for introducing said particulates into said medium for passage through said channel, the improvement wherein said channel is generally rectangular in crosssection and has a width to thickness aspect ratio lying in the range 3-50 to 1.
Claim 2
Independent Claim
97 words
An apparatus for separating particulates suspended in a fluid medium according to their effective masses, said apparatus having an annular cylindrical channel with a cylinder axis, said channel being sufficiently thin in the radial dimension to effect laminar flow therein, means for rotating said channel about said axis, means for passing said fluid medium circumferentially through said channel, and means for introducing said particulates into said medium for passage through said channel, the improvement wherein said channel is generally rectangular in crosssection and has a width to thickness aspect ratio lying in the range 3-50 to 1.
Claim 3
Dependent Claim
17 words
An apparatus of claim 1 wherein said aspect ratio lies in the range of 3-20 to 1.
Claim 4
Dependent Claim
32 words
An apparatus of claim 1 or 2 wherein the ratio of the thickness of said channel to the characteristic height of the particulates to be separated is greater than 5 to 1.
Claim 5
Dependent Claim
17 words
An apparatus of claim 1 or 2 wherein said channel is formed of a flattened capillary tube.
Claim 6
Dependent Claim
26 words
An apparatus of claim 4 wherein said channel is formed of a flattened capillary tube and the rectangular cross-section of said channel has rounded end sections.
Claim 7
Dependent Claim
51 words
An apparatus of claim 5 wherein said channel is formed of a flattened capillary tube and the rectangular cross-section of said channel has rounded end sections and the ratio of the thickness of said channel to the characteristic height of the particulates to be separated is greater than 5 to 1.
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) | 1984-08-24 | 1985-02-23 | 1985-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-24 | 1989-02-23 | 1989-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-24 | 1993-02-23 | 1993-08-25 | $7700.00 | Window Closed / Lapsed |