US3905330A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic deposition of particles
Assignee: Individual
•
Filing: 1974-08-01
•
Granted: 1975-09-16
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Expires: 1994-08-01
Abstract
Abstract A device for spraying particles for example onto crops comprises a barrel with a discharge nozzle and means for inducing, by the triboelectric effect or other means, electric charge into the particles. Preferably means for generating an electric field are provided near the nozzle, this field serving to propel and guide particles onto the target.
Inventors
- 👤 Ronald Alan Coffee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:38
CPC Classifications
B; B05; B05B; B05B5/00; B05B5/025; B05B5/047
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
58 words
A device for electrostatically depositing particles onto a surface at earth potential, such device comprising a casing, means for introducing particles to be deposited into the interior of the casing, a discharge barrel extending from the casing and triboelectricity inducing means movable within the casing which also propel particles from the casing through and out of the barrel.
Claim 2
Independent Claim
58 words
A device for electrostatically depositing particles onto a surface at earth potential, such device comprising a casing, means for introducing particles to be deposited into the interior of the casing, a discharge barrel extending from the casing and triboelectricity inducing means movable within the casing which also propel particles from the casing through and out of the barrel.
Claim 3
Dependent Claim
13 words
The device of claim 1 wherein the triboelectricity inducing means comprises a fan.
Claim 4
Dependent Claim
42 words
The device of claim 2 wherein the casing is generally circular in form, wherein a connection from a container for the particles extends to the centre of the casing and wherein a shaft carrying the fan blades extends along the said centre.
Claim 5
Dependent Claim
23 words
The device of claim 2 wherein the barrel is tangentially disposed to the casing, the fan being a centrifugal fan with arcuate blades.
Claim 6
Dependent Claim
19 words
The device of claim 1 comprising means for generating an electrostatic field extending from the front of the barrel.
Claim 7
Dependent Claim
32 words
The device of claim 5 wherein said means are constituted by an electrode surrounding the front of the barrel and means for charging the said electrode from charged particles in the barrel.
Claim 8
Dependent Claim
31 words
The device of claim 5 wherein said means concentrate a cloud of particles emerging from the nozzle so as to create a high-voltage space-charge to act as a directional electric field.
Claim 9
Dependent Claim
17 words
The device of claim 6 wherein the said means of electrode charging is a corona discharge needle.
Claim 10
Dependent Claim
21 words
The device of claim 6 wherein the said means of electrode charging is an electrical conductor positioned to contact charged particles.
Claim 11
Dependent Claim
12 words
The device of claim 6 wherein the electrode is toroidal or spheroidal.
Claim 12
Dependent Claim
14 words
The device of claim 1 including moist particles in the interior of the casing.
Claim 13
Independent Claim
79 words
A device for electrostatically depositing particles on a surface at a lower potential such device comprising a tubular conduit, means for introducing particles into the conduit, means for driving particles along the conduit to a discharge outlet, means for inducing by triboelectricity electric charge to the particles driven along the conduit, electrically chargeable means for generating a directional electric field around said discharge outlet and means for conductively connecting said electRically chargeable means with charged particles in the conduit.
Claim 14
Independent Claim
79 words
A device for electrostatically depositing particles on a surface at a lower potential such device comprising a tubular conduit, means for introducing particles into the conduit, means for driving particles along the conduit to a discharge outlet, means for inducing by triboelectricity electric charge to the particles driven along the conduit, electrically chargeable means for generating a directional electric field around said discharge outlet and means for conductively connecting said electRically chargeable means with charged particles in the conduit.
Claim 15
Dependent Claim
27 words
The device of claim 12 including means of concentrating the charged cloud at the nozzle so as to produce a directional electrical field by the spacecharge potential.
Claim 16
Dependent Claim
20 words
The device of claim 12 wherein the conduit forms a loop connecting the inlet and the outlet of a fan.
Claim 17
Independent Claim
102 words
A device for electrostatically depositing particles such device comprising a first duct forming a closed circuit and containing a powder, part of the walls of said duct being of an electrically non-conductive material, means for inducing a flow of gas through said duct, electrical discharge means extending through said electrically non-conductive part of the walls of said duct for removing electric charge from said powder in said flow of gas, capacitor means electrically connected to said electrical discharge means, and means separate from said duct for directing a flow of air containing the powder to be ejected adjacent to said capacitor means.
Claim 18
Independent Claim
102 words
A device for electrostatically depositing particles such device comprising a first duct forming a closed circuit and containing a powder, part of the walls of said duct being of an electrically non-conductive material, means for inducing a flow of gas through said duct, electrical discharge means extending through said electrically non-conductive part of the walls of said duct for removing electric charge from said powder in said flow of gas, capacitor means electrically connected to said electrical discharge means, and means separate from said duct for directing a flow of air containing the powder to be ejected adjacent to said capacitor means.
Claim 19
Independent Claim
75 words
A device for the electrostatic deposition of particles such device comprising an apparatus for applying an electric charge to a powder comprising a duct having at least the inner surface of its walls formed of an electrically conductive material, means for causing a stream of gas containing said powder to flow through the duct, an earthed corona discharge electrode within said duct and means for applying a voltage to the inner surface of said duct.
Claim 20
Independent Claim
75 words
A device for the electrostatic deposition of particles such device comprising an apparatus for applying an electric charge to a powder comprising a duct having at least the inner surface of its walls formed of an electrically conductive material, means for causing a stream of gas containing said powder to flow through the duct, an earthed corona discharge electrode within said duct and means for applying a voltage to the inner surface of said duct.
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) | 1978-09-15 | 1979-03-17 | 1979-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-15 | 1983-03-17 | 1983-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-15 | 1987-03-17 | 1987-09-16 | $7700.00 | Window Closed / Lapsed |