Patent US2773170A successfully refreshed from Google Patents.
Patent US4148595A successfully refreshed from Google Patents.
US4148595A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating for aerodynamic shield in apparatus for making non-woven web
Assignee: EIDP Inc
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Filing: 1977-09-28
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Granted: 1979-04-10
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Expires: 1997-09-28
Abstract
Abstract The aerodynamic shield members of the apparatus for electrostatically charging fibrous material disclosed in U.S. Pat. No. 3,860,369 are coated with a material having a resistance of between 5× 10 12 and 10 14 ohms/sq to reduce arcing at higher charge levels.
Inventors
- 👤 Thomas K. Bednarz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:46
CPC Classifications
D; D01; D01D; D01D5/00; D01D5/0007; D04; D04H; D04H3/00; D04H3/08; D04H3/16; H; H01; H01T; H01T19/00
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
205 words
In an apparatus for forming a fibrous web that includes a chamber containing therein a means for flash spinning a polymer solution to form a plexifilamentary strand entrained in a gaseous stream, means at one location for spreading the strand to form a web and oscillating the web in a generally vertical plane in a plurality of downward radial directions toward a collecting surface, an ion gun connected to a high voltage power source, and an opposed grounded target electrode positioned on opposite sides of said plane whereby a corona discharge occurs between said ion gun and said target electrode, said target electrode having a surface facing said ion gun, said surface of said target electrode facing said ion gun being covered with a material having a resistance of between 1 × 10 6 ohms and 10 10 ohms, and an aerodynamic shield having front and rear members disposed on each side of said plane below said ion gun and said target electrode, said members having surfaces facing said plane, the improvement comprising: said surfaces of said front and rear members facing said plane being covered by a slightly conductive material having a stable resistance of between 5 × 10 12 and 10 14 ohms/sq.
Claim 2
Dependent Claim
205 words
In an apparatus for forming a fibrous web that includes a chamber containing therein a means for flash spinning a polymer solution to form a plexifilamentary strand entrained in a gaseous stream, means at one location for spreading the strand to form a web and oscillating the web in a generally vertical plane in a plurality of downward radial directions toward a collecting surface, an ion gun connected to a high voltage power source, and an opposed grounded target electrode positioned on opposite sides of said plane whereby a corona discharge occurs between said ion gun and said target electrode, said target electrode having a surface facing said ion gun, said surface of said target electrode facing said ion gun being covered with a material having a resistance of between 1 × 10 6 ohms and 10 10 ohms, and an aerodynamic shield having front and rear members disposed on each side of said plane below said ion gun and said target electrode, said members having surfaces facing said plane, the improvement comprising: said surfaces of said front and rear members facing said plane being covered by a slightly conductive material having a stable resistance of between 5 × 10 12 and 10 14 ohms/sq.
References Cited (Backward Citations)
US3860369A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-09 | 1982-10-09 | 1983-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-09 | 1986-10-09 | 1987-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-09 | 1990-10-09 | 1991-04-10 | $7700.00 | Window Closed / Lapsed |