US3655307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrostatic pinning of dielectric film
Assignee: EIDP Inc
•
Filing: 1970-03-23
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Granted: 1972-04-11
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Expires: 1990-03-23
Abstract
Abstract Apparatus for electrostatically pinning a moving dielectric web to a roll which comprises a first electrode and a second, insulated electrode independent of the roll, and means for establishing a potential difference therebetween.
Inventors
- 👤 William E Hawkins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:13
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/88; B29C48/911; B29C48/9135; B29C48/915; B29C48/9165; B29C48/03; B29C48/07; B29C48/08; B29C48/914
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
117 words
An apparatus for pinning a dielectric film extruded from a hopper onto an electrically grounded moving surface which comprises a first electrode and a second, grounded electrode spaced from said hopper and electrically insulated from the first electrode by a dielectric coating thereon which intersects substantially all of the straight linear paths between the first and second electrodes, a high voltage current source and means connecting the current source to the first electrode to establish an electric potential difference between the first and second electrodes, the first electrode being in spaced relationship to the moving surface, the distance between the first and second electrodes being less than the distance between the first electrode and the moving surface.
Claim 2
Independent Claim
117 words
An apparatus for pinning a dielectric film extruded from a hopper onto an electrically grounded moving surface which comprises a first electrode and a second, grounded electrode spaced from said hopper and electrically insulated from the first electrode by a dielectric coating thereon which intersects substantially all of the straight linear paths between the first and second electrodes, a high voltage current source and means connecting the current source to the first electrode to establish an electric potential difference between the first and second electrodes, the first electrode being in spaced relationship to the moving surface, the distance between the first and second electrodes being less than the distance between the first electrode and the moving surface.
Claim 3
Dependent Claim
15 words
An apparatus of claim 1 wherein the high voltage source is a unidirectional current source.
Claim 4
Dependent Claim
12 words
An apparatus of claim 2 wherein the high voltage source is positive.
Claim 5
Dependent Claim
29 words
An apparatus of claim 1 wherein the distance between the first electrode and the moving surface is less than the distance between the second electrode and the moving surface.
Claim 6
Dependent Claim
18 words
An apparatus of claim 1 further comprising means for substantially surrounding at least the first electrode with gas.
Claim 7
Dependent Claim
29 words
An apparatus of claim 1 wherein the electrically grounded moving surface is a quenching surface and the film is thermoplastic, melt-extruded onto the quenching surface from a die orifice.
Claim 8
Dependent Claim
52 words
An apparatus of claim 6 wherein the second electrode is so positioned as to intersect at least 50 percent of the straight linear paths between the first electrode and that portion of the melt-extruded film extending from the die orifice to the point of touchdown of the film onto the quenching surface.
Claim 9
Dependent Claim
73 words
An apparatus of claim 1 wherein the second electrode is arcuate in configuration and is positioned farther from the moving surface than the first electrode, the concave surface of the second electrode facing the moving surface, the second electrode being insulated from the first electrode by a layer of dielectric resin on at least the concave surface thereof and wherein the first electrode is positioned within the arc defined by the second electrode.
Claim 10
Dependent Claim
43 words
An apparatus of claim 7 wherein the second electrode and the layer of dielectric resin have at least one aperture formed therethrough, the apparatus further comprising means for passing a gaseous stream through the aperture and toward the first electrode and the film.
References Cited (Backward Citations)
US3427686A
Cited
US3520959A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |