Patent US3557301A successfully refreshed from Google Patents.
US3557301A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sheathing of electrical cables
Assignee: Pirelli and C SpA
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Filing: 1968-04-08
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Granted: 1971-01-19
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Expires: 1988-04-08
Abstract
Abstract An aluminum tube is extruded over a core containing electrical conductors insulated with paper which has been impregnated with an insulating composition, the extrusion being carried out while introducing additional insulating composition under pressure between the core and the aluminum tube. Subsequent to extrusion, the aluminum tube or sheath is sinusoidally corrugated with shallow corrugations falling within specified dimensional limits.
Inventors
- 👤 Paolo Gazzana Priaroggia
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:13
CPC Classifications
H; H01; H01B; H01B13/00; H01B13/0009; H01B13/22; H01B13/24; H01B13/245; H01B7/00; H01B7/17; H01B7/18; H01B7/20; H01B7/201; H01B7/28; H01B9/00; H01B9/06; H01B9/0611
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
92 words
An electric cable comprising a core having a conductor surrounded by a layer of insulation, an outer metallic sheath surround said core and an insulating composition intermediate say said layer and said outer metallic sheath, said sheath being sinusoidally corrugated with a minimum interior diameter at least 1 millimeter larger than the outside diameter of said layer and with the depth of the corrugations in the range of between 0.5 and 1.5 millimeters and the ratio of said depth to the pitch of said corrugations in the range of 1:25 to 1:15.
Claim 2
Dependent Claim
92 words
An electric cable comprising a core having a conductor surrounded by a layer of insulation, an outer metallic sheath surround said core and an insulating composition intermediate say said layer and said outer metallic sheath, said sheath being sinusoidally corrugated with a minimum interior diameter at least 1 millimeter larger than the outside diameter of said layer and with the depth of the corrugations in the range of between 0.5 and 1.5 millimeters and the ratio of said depth to the pitch of said corrugations in the range of 1:25 to 1:15.
Claim 3
Dependent Claim
13 words
An electric cable according to claim 1, wherein said sheath consists of aluminum.
Claim 4
Dependent Claim
24 words
An electric cable according to claim 1, wherein the entire space between said layer and the corrugated sheath is filled with said insulating composition.
Claim 5
Dependent Claim
15 words
An electric cable according to claim 3, wherein said sheath is a seamless aluminum tube.
Claim 6
Dependent Claim
17 words
An electric cable according to claim 4, wherein said layer is paper impregnated with said insulating composition.
References Cited (Backward Citations)
US2995616A
Cited
US2817363A
Cited
US2890263A
Cited
US2870792A
Cited
US3287490A
Cited
US3394400A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |