Patent US3714565A successfully refreshed from Google Patents.
US3714565A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic particle analyzing apparatus with improved aperture tube
Assignee: Coulter Electronics Inc
•
Filing: 1971-03-26
•
Granted: 1973-01-30
•
Expires: 1991-03-26
Abstract
Abstract An aperture tube for use with a Coulter type particle analyzing device is constructed with its interior surface covered with conductive material such as metal, its exterior surface covered with conductive material such as metal, the aperture being provided in a corundum wafer set into the bottom end of the tube. The conductive coating approaches the aperture as close as several aperture diameters, surrounding the aperture so that except for the path of the aperture itself, flow of aperture current through the electrolyte is minimized, thereby decreasing heating of the electrolyte with its attendant noise. The invention is primarily applicable to situations where the aperture current is a high frequency current to avoid polarization. The aperture tube is useful in the configuration where it is the transducer for a Coulter particle analyzing apparatus or it may be used as part of a system in which size as ascertained by use of the Coulter method is utilized in connection with a droplet forming and separating device to classify particles by size.
Inventors
- 👤 W Coulter
- 👤 W Hogg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:38
CPC Classifications
G; G01; G01N; G01N15/00; G01N15/10; G01N15/1031; G01N15/12; G01N15/13
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
75 words
An aperture tube particularly adapted for use in a Coulter particle analyzing device and comprising a vessel having a wall of electrically insulative material, a substantially closed bottom end portion with a minute aperture extending therethrough and coverings of electrically conductive material on the inner and outer respective surfaces of said bottom end portion of said vessel, each covering surrounding said aperture and being spaced from said aperture by a few diameters of said aperture.
Claim 2
Dependent Claim
75 words
An aperture tube particularly adapted for use in a Coulter particle analyzing device and comprising a vessel having a wall of electrically insulative material, a substantially closed bottom end portion with a minute aperture extending therethrough and coverings of electrically conductive material on the inner and outer respective surfaces of said bottom end portion of said vessel, each covering surrounding said aperture and being spaced from said aperture by a few diameters of said aperture.
Claim 3
Dependent Claim
27 words
The aperture tube according to claim 1 wherein said tube has a tip at said bottom end portion thereof and said aperture is situated in said tip.
Claim 4
Dependent Claim
17 words
The aperture tube according to claim 1 wherein said aperture tube narrows to said bottom end portion.
Claim 5
Dependent Claim
51 words
The aperture tube according to claim 1 wherein said wall comprises inner and outer partitions spaced apart, with said inner covering on the interior surface of said inner partition and said outer covering on the exterior surface of said outer partition, said partitions being joined at the location of said aperture.
Claim 6
Dependent Claim
36 words
The aperture tube according to claim 1 wherein said coverings of electrically conductive material on the inner and outer wall surfaces of said vessel are disposed over a substantial portion of said surfaces and form electrodes.
Claim 7
Dependent Claim
16 words
The aperture tube according to claim 1 wherein at least one of said coverings is metal.
Claim 8
Dependent Claim
16 words
The aperture tube according to claim 1 wherein said vessel is made of a synthetic resin.
Claim 9
Dependent Claim
55 words
The aperture tube according to claim 1 wherein said bottom end portion has a cavity therein, a wafer having said aperture therein is disposed in said cavity, and said coverings extend over a portion of said wafer and engage said wafer on the upper and lower surfaces thereof to hold said wafer in said cavity.
Claim 10
Dependent Claim
17 words
The aperture tube according to claim 1 wherein at least one of said coverings is a coating.
Claim 11
Dependent Claim
138 words
The aperture tube according to claim 1 wherein said vessel comprises an elongate tubular cylindrical member of electrical insulating material having a narrowed part at its bottom end, said inner and outer coverings comprise metallic tubular cylinders coaxially arranged in intimate engagement with the respective interior and exterior surfaces of said insulating tubular cylindrical member and each of said metallic cylinders has an annular radially inwardly extending flange at the bottom end thereof engaged with said narrowed part on its upper and lower surfaces but for a small central location, there being a wafer of electrically non-conductive material disposed at said central location and having a passageway therethrough which defines said aperture, said passageway extending generally in an axial direction with respect to said cylindrical member and each of said flanges respectively surrounding one end of said passageway.
Claim 12
Dependent Claim
40 words
The aperture tube according to claim 10 wherein a cavity is formed in said narrowed part at said central location, said wafer is disposed in said cavity, and said flanges engage said wafer on the upper and lower surfaces thereof.
Claim 13
Dependent Claim
162 words
A particle analyzing device of the Coulter type comprising an aperture tube including a vessel having a wall of electrically insulative material, a substantially closed bottom end portion with a minute aperture extending therethrough, and coverings of electrically conductive material on the inner and outer respective surfaces of said bottom end portion of said vessel, each covering surrounding said aperture and being spaced from said aperture by a few diameters of said aperturE, a body of electrolyte in said aperture tube, the lower portion of which is immersed in a second body of electrolyte, one of said bodies having particles therein, means for causing a flow of fluid containing particles in suspension from one of said bodies of electrolyte through said aperture, conductors connected respectively with said coverings, and alternating current generating means for generating a high frequency electric current and for applying same to said conductors for causing said high frequency current to flow through said aperture simultaneously with said particles.
Claim 14
Dependent Claim
162 words
A particle analyzing device of the Coulter type comprising an aperture tube including a vessel having a wall of electrically insulative material, a substantially closed bottom end portion with a minute aperture extending therethrough, and coverings of electrically conductive material on the inner and outer respective surfaces of said bottom end portion of said vessel, each covering surrounding said aperture and being spaced from said aperture by a few diameters of said aperturE, a body of electrolyte in said aperture tube, the lower portion of which is immersed in a second body of electrolyte, one of said bodies having particles therein, means for causing a flow of fluid containing particles in suspension from one of said bodies of electrolyte through said aperture, conductors connected respectively with said coverings, and alternating current generating means for generating a high frequency electric current and for applying same to said conductors for causing said high frequency current to flow through said aperture simultaneously with said particles.
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) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |