Patent US253171A successfully refreshed from Google Patents.
US3666879A
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Power cable
Assignee: International Standard Electric Corp
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Filing: 1970-10-20
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Granted: 1972-05-30
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Expires: 1990-10-20
Abstract
Abstract The geometric dimensions and power losses of a power cable are maintained constant along its length, notwithstanding changing ambient thermal conditions. This is made possible by changing the conductor material at different locations, for example, copper to aluminum, having different thermal resistivity. The sections of different conductor material are joined by conventional techniques such as welding, soldering, etc. Copper is used at the ends to simplify splicing.
Inventors
- 👤 Christian Worm Hirsch
- 👤 John Normann Johnsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:36
CPC Classifications
H; H01; H01B; H01B9/00; H01B9/006; H01B7/00; H01B7/14
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
31 words
A power cable according to claim 1, wherein a substantial portion of a length of each said conductor is made of aluminum and the end portions thereof are made of copper.
Claim 2
Dependent Claim
16 words
A power cable according to claim 2, wherein said conductors are multistrand conductors arranged in layers.
Claim 3
Dependent Claim
22 words
A power cable according to claim 3, wherein said plurality of conductors include the same number of wires throughout the cable length.
Claim 4
Dependent Claim
25 words
A power cable according to claim 4, wherein the geometrical cross-section and shape of each of the wires are substantially uniform throughout the cable length.
Claim 5
Dependent Claim
41 words
A power cable according to claim 5, wherein the cross-section of the cable comprises aluminum wires and copper wires selectively arranged in inner and outer layers along different longitudinal sections to provide gradual changes of material along the length of cable.
Claim 6
Dependent Claim
22 words
A power cable according to claim 6, wherein said aluminum wires are in inner layers and said copper wires in outer layers.
Claim 7
Dependent Claim
28 words
A power cable according to claim 6, wherein the joints of adjacent wires in a multistrand layered conductor are spaced apart within a predetermined length of the cable.
Claim 8
Dependent Claim
32 words
A power cable according to claim 8, wherein said joints of adjacent wires around the circumference of said cable are stagger-ed to provide an interleaved pattern along the length of the layer.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-30 | 1975-11-29 | 1976-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-30 | 1979-11-29 | 1980-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-30 | 1983-11-29 | 1984-05-30 | $7700.00 | Window Closed / Lapsed |