US5174160A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of diagnosing electric wires and cables for deterioration of their polymer-insulation and a measuring apparatus used therefor
Assignee: Hitachi Cable Ltd
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Filing: 1990-09-18
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Granted: 1992-12-29
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Expires: 2010-09-18
Abstract
Abstract This invention relates to a method or apparatus by which comparatively low-voltage electric wires and cables laid at power stations and other locations can be diagnosed for deterioration of their polymer-insulation in a non-destructive way. The method or apparatus comprises applying a torsional force to the electric wire or cable, detecting the resulting repulsion as a torque, and estimating the degree of deterioration of the polymer-insulation in the electric wire or cable on the basis of the detected value of torque.
Inventors
- 👤 Yousuke Morita
- 👤 Toshiaki Yagi
- 👤 Waichiro Kawakami
- 👤 Seiji Kamimura
- 👤 Hideki Yagyu
- 👤 Osamu Mochizuki
- 👤 Takao Onishi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:56
CPC Classifications
G; G01; G01N; G01N3/00; G01N3/22; G01N17/00
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
60 words
A method of estimating the degree of deterioration of an electric wire or cable having a polymer insulation comprising the steps of: applying a torsional force to said electric wire or cable; detecting the resulting repulsion as a torque; and estimating the degree of deterioration in said electric wire or cable on the basis of the detected value of torque.
Claim 2
Independent Claim
60 words
A method of estimating the degree of deterioration of an electric wire or cable having a polymer insulation comprising the steps of: applying a torsional force to said electric wire or cable; detecting the resulting repulsion as a torque; and estimating the degree of deterioration in said electric wire or cable on the basis of the detected value of torque.
Claim 3
Dependent Claim
19 words
The method according to claim 1, wherein said electric wire or cable is a low-voltage electric wire or cable.
Claim 4
Dependent Claim
12 words
The method according to claim 1, wherein said polymer insulation comprises polyethylene.
Claim 5
Dependent Claim
13 words
The method according to claim 1, wherein said polymer insulation comprises crosslinked polyethylene.
Claim 6
Dependent Claim
13 words
The method according to claim 1, wherein said polymer insulation comprises polyvinyl chloride.
Claim 7
Dependent Claim
16 words
The method according to claim 1, wherein the polymer insulation comprises a sheath and an insulator.
Claim 8
Dependent Claim
18 words
The method according to claim 6, wherein said sheath comprises polyvinyl chloride and said insulator comprises crosslinked polyethylene.
Claim 9
Dependent Claim
23 words
The method according to claim 1, wherein said step of estimating comprises comparing the detected value of torque with a known torque value.
Claim 10
Independent Claim
91 words
A method of estimating the degree of deterioration of a polymer insulation in an electric wire or cable, the method comprising the steps of: holding said electric wire or cable in at least first and second points along a longitudinal axis thereof; applying a substantially non-destructive torsional force to said electric wire or cable at the first holding point; detecting the resulting repulsion against the torsional force as a torque at the second holding point; and estimating the degree of deterioration of said polymer insulation from the detected value of torque.
Claim 11
Independent Claim
91 words
A method of estimating the degree of deterioration of a polymer insulation in an electric wire or cable, the method comprising the steps of: holding said electric wire or cable in at least first and second points along a longitudinal axis thereof; applying a substantially non-destructive torsional force to said electric wire or cable at the first holding point; detecting the resulting repulsion against the torsional force as a torque at the second holding point; and estimating the degree of deterioration of said polymer insulation from the detected value of torque.
Claim 12
Dependent Claim
19 words
The method according to claim 9, wherein said electric wire or cable is a low-voltage electric wire or cable.
Claim 13
Dependent Claim
12 words
The method according to claim 9, wherein said polymer insulation comprises polyethylene.
Claim 14
Dependent Claim
12 words
The method according to claim 9, wherein said polymer comprises crosslinked polyethylene.
Claim 15
Dependent Claim
13 words
The method according to claim 9, wherein said polymer insulation comprises polyvinyl chloride.
Claim 16
Dependent Claim
16 words
The method according to claim 9, wherein the polymer insulation comprises a sheath and an insulator.
Claim 17
Dependent Claim
18 words
The method according to claim 14, wherein said sheath comprises polyvinyl chloride and said insulator comprises crosslinked polyethylene.
Claim 18
Dependent Claim
20 words
The method according to claim 9, wherein said step of estimating comprises comparing the detected torque with a known torque.
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US3724265A
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US4055992A
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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) | 1995-12-29 | 1996-06-29 | 1996-12-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-29 | 2000-06-29 | 2000-12-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-29 | 2004-06-29 | 2004-12-29 | $7700.00 | Window Closed / Lapsed |