Patent US4425496A successfully refreshed from Google Patents.
US4425496A
Expired / Lapsed
US
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Removal of metal coating from dielectric material
Assignee: Electricite de France SA
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Filing: 1980-05-16
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Granted: 1984-01-10
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Expires: 2000-05-16
Abstract
Abstract The metal coating on a dielectric sheet or strip, for instance for use in capacitors, is locally removed by a Corona discharge between the sheet and a point electrode. A current return electrode contacts the sheet and is located in the return path to a HV generator connected to the point electrode.
Inventors
- 👤 Daniel Le Fur
- 👤 Robert Haug
- 👤 Max Goldman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:26
CPC Classifications
H; H01; H01G; H01G13/00; H01G13/06
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
133 words
A process for locally demetallizing a metal coating on a strip of dielectric material, comprising the steps of moving said strip along a predetermined path while maintaining said coating in contact with a current return electrode held at a reference potential and while supporting the side of said strip opposite from said coating with a support means held at said reference potential, and applying, to discharge electrode means closely confronting said coating and having a high curvature portion of much greater curvature than that of the portion of said strip which confronts said coating, a DC electrical voltage adapted to maintain a Corona discharge between said discharge electrode means and said coating, whereby demetallization occurs along a predetermined defined zone of said strip as the latter is moved, without damaging said dielectric material.
Claim 2
Dependent Claim
133 words
A process for locally demetallizing a metal coating on a strip of dielectric material, comprising the steps of moving said strip along a predetermined path while maintaining said coating in contact with a current return electrode held at a reference potential and while supporting the side of said strip opposite from said coating with a support means held at said reference potential, and applying, to discharge electrode means closely confronting said coating and having a high curvature portion of much greater curvature than that of the portion of said strip which confronts said coating, a DC electrical voltage adapted to maintain a Corona discharge between said discharge electrode means and said coating, whereby demetallization occurs along a predetermined defined zone of said strip as the latter is moved, without damaging said dielectric material.
Claim 3
Dependent Claim
23 words
A process according to claim 1, wherein the strip is moved past the discharge electrode means to remove the coating along a line.
Claim 4
Dependent Claim
28 words
A process according to claim 1, wherein the electrode means are brought to a positive voltage with respect to the coating so as to strip the coating locally.
Claim 5
Dependent Claim
23 words
A process according to claim 1, wherein the strip is supported and driven by low curvature means made from dielectric thermally conducting material.
Claim 6
Dependent Claim
27 words
A process according to claim 1, wherein said electrical voltage is negative with respect to said coating so as to demetallize said coating by oxidizing it locally.
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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) | 1987-01-09 | 1987-07-11 | 1988-01-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-09 | 1991-07-11 | 1992-01-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-09 | 1995-07-11 | 1996-01-10 | $7700.00 | Window Closed / Lapsed |