US3784876A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Static decharger
Assignee: McDonnell Douglas Corp
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Filing: 1972-04-17
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Granted: 1974-01-08
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Expires: 1992-04-17
Abstract
Abstract Electrostatically charged nonconducting fluid is rendered temporarily conductive by subjecting the fluid to ionizing radiation of selected radioactive material. Ion pairs are created by the radiation and a predetermined density of ions is produced whereby the fluid is made sufficiently conductive so that it practically cannot hold a charge. While conductive, any acquired charge is free to drain to ground. A volume ionizing embodiment of the invention includes radioactive material disposed in a grounded grating configuration through which the fluid flows and is ionized, and any fluid charge is largely drained to ground through the grating. In another version of the invention, a laminar ionizing embodiment includes radioactive material disposed in a sleeve configuration through which the fluid flows and an adjacent layer of fluid having an opposite charge to its fluid core is produced, and charge neutralization is achieved by subsequent mixing of the fluid layer and core.
Inventors
- 👤 De Gaston A Neal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:27
CPC Classifications
H; H05; H05F; H05F3/00; H05F3/06
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
79 words
A process of reducing electrostatic charges in an electrically charged fluid, which comprises the steps of: subjecting said charged fluid to ionizing radiation of predetermined intensity and ionization to render it conductive and elevated to at least a predetermined ion density for a predetermined time duration; contacting said charged fluid to grounded structure during said predetermined time duration; and draining said charges in said charged fluid to ground through said grounded structure while said charged fluid is rendered conductive.
Claim 2
Dependent Claim
79 words
A process of reducing electrostatic charges in an electrically charged fluid, which comprises the steps of: subjecting said charged fluid to ionizing radiation of predetermined intensity and ionization to render it conductive and elevated to at least a predetermined ion density for a predetermined time duration; contacting said charged fluid to grounded structure during said predetermined time duration; and draining said charges in said charged fluid to ground through said grounded structure while said charged fluid is rendered conductive.
Claim 3
Dependent Claim
84 words
The invention as defined in claim 1 wherein said radiation is of predetermined characteristic range, and said grounded structure is of predetermined dimensions and includes radioactive material of predetermined activity, and further comprising the step of flowing said charged fluid at a predetermined rate through said grounded radioactive structure of predetermined dimensions whereby said charged fluid is subjected to said ionizing radiation to render it conductive and elevated to at least said predetermined ion density while passing through and contacting said grounded radioactive structure.
Claim 4
Dependent Claim
83 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation of predetermined intensity and ionization to render it conductive and elevated to at least a predetermined ion density for a predetermined time duration; and means for contacting said charged fluid to ground and draining said charges in said charged fluid to ground while it is rendered conductive, whereby said charged fluid is decharged to at least a predetermined level.
Claim 5
Dependent Claim
83 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation of predetermined intensity and ionization to render it conductive and elevated to at least a predetermined ion density for a predetermined time duration; and means for contacting said charged fluid to ground and draining said charges in said charged fluid to ground while it is rendered conductive, whereby said charged fluid is decharged to at least a predetermined level.
Claim 6
Dependent Claim
42 words
The invention as defined in claim 3 wherein said radiation includes beta radiatioN with its characteristic range, and said contacting and charge draining means includes a conductive means for housing said charged fluid, and ground means connecting with said conductive housing means.
Claim 7
Dependent Claim
79 words
A process of reducing electrostatic charges in an electrically charged fluid, which comprises the steps of: subjecting said charged fluid to ionizing radiation to render a laminar layer thereof conductive; draining said charges in said laminar layer to ground while it is rendered conductive and leaving charges in said laminar layer equally opposite to the charges in the remainder of said charged fluid; and mixing said laminar layer with said remainder of said charged fluid to neutralize the same.
Claim 8
Dependent Claim
79 words
A process of reducing electrostatic charges in an electrically charged fluid, which comprises the steps of: subjecting said charged fluid to ionizing radiation to render a laminar layer thereof conductive; draining said charges in said laminar layer to ground while it is rendered conductive and leaving charges in said laminar layer equally opposite to the charges in the remainder of said charged fluid; and mixing said laminar layer with said remainder of said charged fluid to neutralize the same.
Claim 9
Dependent Claim
26 words
The invention as defined in claim 5 further comprising the step of flowing said charged fluid through a radioactive structure to subject it to ionizing radiation.
Claim 10
Dependent Claim
84 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation to render a laminar layer thereof conductive; means for draining said charges in said laminar layer to ground while it is rendered conductive and leaving charges in said laminar layer equally opposite to the charges in the remainder of said charged fluid; and means for mixing said laminar layer with said remainder of said charged fluid to neutralize the same.
Claim 11
Dependent Claim
84 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation to render a laminar layer thereof conductive; means for draining said charges in said laminar layer to ground while it is rendered conductive and leaving charges in said laminar layer equally opposite to the charges in the remainder of said charged fluid; and means for mixing said laminar layer with said remainder of said charged fluid to neutralize the same.
Claim 12
Dependent Claim
36 words
The invention as defined in claim 7 wherein said fluid subjecting means includes a radioactive sleeve through which said charged fluid can be flowed and subjected to ionizing radiation to render a laminar layer thereof conductive.
Claim 13
Dependent Claim
37 words
The invention as defined in claim 8 further comprising a needle electrode, charge extracting means positioned upstream of said sleeve for reducing exceptionally high levels of electrostatic charges in said charged fluid prior to reaching said sleeve.
Claim 14
Dependent Claim
62 words
The invention as defined in claim 8 wherein said charge draining means includes a conductive means for mounting said sleeve therein and for housing said charged fluid, and ground means connecting with said conductive housing means, said sleeve being conductive and mounted in ground contact to said conductive housing means whereby said sleeve also serves as part of said charge draining means.
Claim 15
Dependent Claim
34 words
The invention as defined in claim 10 wherein said sleeve includes a radioactive material therein for providing a predetermined available activity and radiation range to produce said equally opposite charges in said laminar layer.
Claim 16
Dependent Claim
54 words
The invention as defined in claim 11 wherein said radiation range is correlated with flow of said charged fluid to provide a thickness of said laminar layer in which the inner velocity thereof is approximately equal to a predetermined percentage of the mean flow velocity of the central core portion of said charged fluid.
Claim 17
Dependent Claim
75 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation to render it conductive, said fluid subjecting means including a radioactive structure having a plurality of passageways through which said charged fluid can be flowed and subjected to ionizing radiation to render it conductive; and means for draining said charges in said charged fluid to ground while it is rendered conductive.
Claim 18
Dependent Claim
75 words
Means for reducing electrostatic charges in an electrically charged fluid, said charge reducing means comprising: means for subjecting said charged fluid to ionizing radiation to render it conductive, said fluid subjecting means including a radioactive structure having a plurality of passageways through which said charged fluid can be flowed and subjected to ionizing radiation to render it conductive; and means for draining said charges in said charged fluid to ground while it is rendered conductive.
Claim 19
Dependent Claim
31 words
The invention as defined in claim 13 wherein said structure comprises a radioactive grating through which said charged fluid can be flowed and subjected to ionizing radiation to render it conductive.
Claim 20
Dependent Claim
54 words
The invention as defined in claim 14 wherein said grating includes elements having a selected radioactive material therein for providing a predetermined available activity and radiation range, said elements having a predetermined configuration and being arranged in a predetermined geometry in said grating to ionize the volume of said charged fluid passing through it.
Claim 21
Dependent Claim
37 words
The invention as dEfined in claim 14 further comprising a needle electrode, charge extracting means positioned upstream of said grating for reducing exceptionally high levels of electrostatic charges in said charged fluid prior to reaching said grating.
Claim 22
Dependent Claim
56 words
The invention as defined in claim 14 wherein said charge draining means includes a conductive means for housing said charged fluid and ground means connecting with said conductive housing means, said grating being conductive and mounted in ground contact to said conductive housing means whereby said grating also serves as part of said charge draining means.
Claim 23
Dependent Claim
62 words
The invention as defined in claim 17 wherein said grating includes a plurality of radioactive strip elements each having a generally rectangular plate configuration of predetermined length, width and thickness, said elements being positioned in parallel with their planes aligned generally with fluid flow direction and having a uniform spacing between said elements correlated to the mean range of said ionizing radiation.
References Cited (Backward Citations)
US2990350A
Cited
US3383560A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |