US4489894A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inductively charged spraying apparatus
Assignee: BTG International Ltd
•
Filing: 1982-02-25
•
Granted: 1984-12-25
•
Expires: 2002-02-25
Abstract
Abstract A spraying apparatus to deliver inductively charged spray, for example to crops. The apparatus includes a spray head and electrodes to apply a potential difference in the region of the spray head to charge spray. An aspirating means is arranged to remove liquid deposited on an electrode to reduce interference with the charging process. When the spray liquid is to be at high potential in the apparatus a long high resistivity supply tube may be provided. The aspirating means may be operated by spray liquid bled from a pressurized supply spray liquid.
Inventors
- 👤 John A. Marchant
- 👤 John F. Hughes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 05:19
CPC Classifications
B; B05; B05B; B05B5/00; B05B5/025; B05B5/043; A; A01; A01M; A01M7/00; A01M7/005; A01M7/006; B05B14/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
161 words
An electrostatic spraying apparatus, comprising: a spray liquid supply means; a spray head having a spray liquid inlet and a spray a first electrode and a second electrode, including means supporting said first and second electrode on said apparatus for applying an electrical potential difference proximally of said spray exit, whereby emergent spray is inductively electrically charged; said first electrode being associated with said spray head and arranged to be in electrical contact with spray liquid supplied by said spray liquid supply means to said spray head; said second electrode comprising a hollow body having a wall provided with at least one aperture through which liquid deposited exteriorly on said wall may pass to the interior of said hollow body; said second electrode being arranged in spaced relation to said spray exit; and asperating means associated with the interior of said hollow body for removing liquid deposited on said second electrode by drawing such liquid through said at least one aperture.
Claim 2
Dependent Claim
161 words
An electrostatic spraying apparatus, comprising: a spray liquid supply means; a spray head having a spray liquid inlet and a spray a first electrode and a second electrode, including means supporting said first and second electrode on said apparatus for applying an electrical potential difference proximally of said spray exit, whereby emergent spray is inductively electrically charged; said first electrode being associated with said spray head and arranged to be in electrical contact with spray liquid supplied by said spray liquid supply means to said spray head; said second electrode comprising a hollow body having a wall provided with at least one aperture through which liquid deposited exteriorly on said wall may pass to the interior of said hollow body; said second electrode being arranged in spaced relation to said spray exit; and asperating means associated with the interior of said hollow body for removing liquid deposited on said second electrode by drawing such liquid through said at least one aperture.
Claim 3
Dependent Claim
60 words
An apparatus according to claim 1, wherein: said spray liquid supply means includes a spray liquid reservoir and pump means for forcing liquid from said reservoir to said spray head; and said apparatus further includes means for supporting said apparatus in a spray delivering configuration for directing delivery of charged spray liquid from said spray exit of said spray head.
Claim 4
Dependent Claim
27 words
An apparatus according to claim 1 in which at least part of the hollow body is made of conductive material, for use with a non-conductive spray liquid.
Claim 5
Dependent Claim
67 words
An apparatus according to claim 1 in which the first electrode is constructed and arranged for use at a potential other than earth potential and the spray liquid supply means includes a spray liquid container and a long liquid flow path means between the container and spray head liquid inlet to restrict electrical leakage from the electrode through the liquid flow path means and any liquid therein.
Claim 6
Dependent Claim
21 words
An apparatus according to claim 4 in which the long liquid flow path means includes a length of electrically insulating tube.
Claim 7
Dependent Claim
23 words
An apparatus according to claim 4 in which the long liquid flow path includes a convoluted path through a body of insulating material.
Claim 8
Dependent Claim
19 words
An apparatus according to claim 4 in which the spray liquid supply means includes an earthed spray liquid container.
Claim 9
Dependent Claim
62 words
An apparatus according to claim 1 in which the aspirating means includes aspiration flow path means from the aspirating means electrode to a source of reduced pressure to apply the reduced pressure at said at least one electrode to remove the liquid, the flow path means also being constructed and arranged to convey removed liquid over at least part of its length.
Claim 10
Dependent Claim
48 words
An apparatus according to claim 8 in which the electrode provided with aspirating means is for use at a potential other than earth potential and the aspiration flow path means is long to reduce electrical leakage from the electrode through the flow path means and any liquid therein.
Claim 11
Dependent Claim
22 words
An apparatus according to claim 8 or claim 9 in which the removed liquid is returned to the spray liquid supply means.
Claim 12
Dependent Claim
29 words
An apparatus according to claim 8 in which the source of reduced pressure is a liquid jet pump such as an ejector operated by the spray liquid supply means.
Claim 13
Dependent Claim
15 words
An apparatus according to claim 1 in which the second electrode is at earth potential.
Claim 14
Dependent Claim
27 words
An apparatus according to claim 12 in which the second electrode also forms a guard against contact by an operator with non-earth potential parts of the apparatus.
Claim 15
Dependent Claim
73 words
An apparatus according to claim 1 in which the spray head has a single said spray exit to produce a spray having one shape of a hollow cone, a solid cone, a hollow fan and a solid fan and the second electrode has the form of a loop conforming to the shape of the spray to preserve a substantially uniform spacing between the spray surface and the nearest point of the second electrode.
Claim 16
Dependent Claim
50 words
An apparatus according to claim 1 in which the second electrode includes at least a portion formed of porous material for the receipt of deposited liquid and providing through the pores of the material means for the passage of deposited liquid by the action of the aspirating means for removal.
Claim 17
Dependent Claim
24 words
An apparatus according to claim 15 including in the second electrode support means to support the porous material portion away from the spray exit.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |