Patent US1852392A successfully refreshed from Google Patents.
US3649834A
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Laminar gas flow radiation detector
Assignee: United States Atomic Energy Commission
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Filing: 1970-10-06
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Granted: 1972-03-14
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Expires: 1990-10-06
Abstract
Abstract A radiation detector for high resolution measurement of energy spectra in flowing gas samples has a first electrode, a parallel second electrode of opposite polarity, and a detection chamber between the two electrodes. An integral pulse or stream of sample gas is passed in laminar flow through the detection chamber. A nonradioactive gas flows around the stream of sample gas to prevent contact and contamination of either electrode with radioactive material, as well as to absorb the radiation from the sample gas for detection.
Inventors
- 👤 Henry W Randolph
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:14
CPC Classifications
G; G01; G01T; G01T7/00; G01T7/02; H; H01; H01J; H01J47/00; H01J47/06
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
216 words
In a gas-filled radiation detector including a first electrode member, a second electrode member parallel to said first electrode member, an enclosed detection chamber between said first and said second electrode members, and a source of electrical potential difference for maintaining said first and second electrodes at opposite electrical polarity, the improvement comprising: a. conduit means for passing a counting gas in laminar flow through said detection chamber; b. injection means disposed within said detection chamber in spaced relationship to said first electrode member and said second electrode member for entraining a sample gas in laminar parallel flow within the flow of said counting gas; c. discharge means coaxially aligned with said injection means for removing said gases from said detection chamber, said injection means, conduit means and discharge means being disposed to prevent contact of the sample gas with said first and said second electrodes; and d. a guard eLectrode having two aligned sections enclosing the end portions of said second electrode but leaving the central portion thereof exposed to define an active detector chamber volume laterally extending from said exposed portion to said first electrode, and means associated with said source of electrical potential difference for maintaining said guard electrode at an electrical potential intermediate the electrical potentials of said first and second electrodes.
Claim 2
Dependent Claim
216 words
In a gas-filled radiation detector including a first electrode member, a second electrode member parallel to said first electrode member, an enclosed detection chamber between said first and said second electrode members, and a source of electrical potential difference for maintaining said first and second electrodes at opposite electrical polarity, the improvement comprising: a. conduit means for passing a counting gas in laminar flow through said detection chamber; b. injection means disposed within said detection chamber in spaced relationship to said first electrode member and said second electrode member for entraining a sample gas in laminar parallel flow within the flow of said counting gas; c. discharge means coaxially aligned with said injection means for removing said gases from said detection chamber, said injection means, conduit means and discharge means being disposed to prevent contact of the sample gas with said first and said second electrodes; and d. a guard eLectrode having two aligned sections enclosing the end portions of said second electrode but leaving the central portion thereof exposed to define an active detector chamber volume laterally extending from said exposed portion to said first electrode, and means associated with said source of electrical potential difference for maintaining said guard electrode at an electrical potential intermediate the electrical potentials of said first and second electrodes.
Claim 3
Dependent Claim
42 words
In the gas-filled radiation detector of claim 1 wherein said first electrode is of elongated cylindrical shape defining said detection chamber therein and said second electrode being an elongated member disposed along the longitudinal axis of said first electrode and detection chamber.
Claim 4
Dependent Claim
27 words
In the gas-filled radiation detector of claim 1 wherein the lower portion of said detection chamber contains packing material to establish laminar flow in said counting gas.
Claim 5
Dependent Claim
59 words
In the gas-filled radiation detector of claim 1 wherein there is included in combination with said injection means, pulsating valve means for sequentially introducing discrete quantities of sample gas in laminar flow and counting means in circuit with said electrodes for counting electrical pulses only while said discrete quantities of sample gas are within said active detector chamber volume.
Claim 6
Dependent Claim
55 words
In the gas-filled radiation detector of claim 1 wherein said injection means and discharge means comprise a sample tube and a coaxially aligned receiving tube respectively, said sample and receiving tubes oppositely extending into said detection chamber to locations spaced from said active detector chamber volume and being parallel to said second and guard electrodes.
Claim 7
Dependent Claim
38 words
In the gas-filled radiation detector of claim 5 wherein said source of electrical potential difference includes means for maintaining said injection and receiving tubes at an electrical potential intermediate the electrical potentials of said first and second electrodes.
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) | 1975-03-14 | 1975-09-13 | 1976-03-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-03-14 | 1979-09-13 | 1980-03-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-03-14 | 1983-09-13 | 1984-03-14 | $7700.00 | Window Closed / Lapsed |