US5214733A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Duct for receiving an optical fibre member
Assignee: Balfour Beatty PLC
•
Filing: 1991-04-23
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Granted: 1993-05-25
•
Expires: 2011-04-23
Abstract
Abstract A duct is provided for receiving an optical fibre member by blowing. The duct is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material such as carbon black held therein or has an electrically conductive material applied thereto preferably the duct has a radially inner layer defining an inside wall of the duct and at least one further layer positioned outwardly of the inner layer, the inner layer being formed of the plastics material which is electrically conductive or has electrically conductive material held therein or had an electrically conductive material applied thereto.
Inventors
- 👤 Alan A. Sadler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 01:45
CPC Classifications
H; H02; H02G; H02G9/00; H02G9/06; G; G02; G02B; G02B6/00; G02B6/44; G02B6/4401; G02B6/4415; G02B6/4416; G02B6/4429; G02B6/4438; G02B6/4439; G02B6/4459; G02B6/46; G02B6/50; G02B6/52
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
42 words
A duct for receiving an optical fibre member, which duct is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of lubricating grade carbon and held therein or applied thereto.
Claim 2
Dependent Claim
42 words
A duct for receiving an optical fibre member, which duct is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of lubricating grade carbon and held therein or applied thereto.
Claim 3
Dependent Claim
55 words
A duct as claimed in claim 1, having a radially inner layer defining an inside wall of the duct and at least one further layer positioned outwardly of the said inner layer, the inner layer being formed of the plastics material which is electrically conductive or has electrically conductive material held therein or applied thereto.
Claim 4
Dependent Claim
14 words
A duct as claimed in claim 2, wherein the said layers are co-extruded layers.
Claim 5
Dependent Claim
54 words
A duct according to claim 1, wherein the duct is formed at least in part of a plastics material which has, as the electically conductive material held therein, a material selected from the group consisting of metallic particles, electrically conductive fibres, for example chopped carbon fibres, and chopped metallic wire, for example copper wire.
Claim 6
Dependent Claim
27 words
A duct according to claim 1, wherein the duct is formed at least in part of a plastics material which is electrically conductive and which is polyaniline.
Claim 7
Dependent Claim
11 words
A duct according to claim 1, which comprises polyethylene or polypropylene.
Claim 8
Independent Claim
56 words
A method of installing an optical fibre member, in which the optical fibre member is installed by a flowing fluid in a duct which is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of lubricating grade carbon and held therein or applied thereto.
Claim 9
Independent Claim
56 words
A method of installing an optical fibre member, in which the optical fibre member is installed by a flowing fluid in a duct which is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of lubricating grade carbon and held therein or applied thereto.
Claim 10
Independent Claim
54 words
A method of installing an optical fibre member, in which the optical fibre member is installed by a flowing fluid in a duct which is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of carbon and held therein or applied thereto.
Claim 11
Independent Claim
54 words
A method of installing an optical fibre member, in which the optical fibre member is installed by a flowing fluid in a duct which is formed at least in part of a plastics material which is electrically conductive or has electrically conductive material which is free of carbon and held therein or applied thereto.
References Cited (Backward Citations)
GB645785A
Cited
GB1032851A
Cited
GB1131142A
Cited
GB1261122A
Cited
GB2135136A
Cited
US4529009A
Cited
GB2156837A
Cited
US4688890A
Cited
US5027864A
Cited
US4892442A
Cited
USH704H
Cited
US4952021A
Cited
WO1990000823A1
Cited
US5046815A
Cited
EP0456909A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-05-24 | 1996-11-23 | 1997-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-05-24 | 2000-11-23 | 2001-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-05-24 | 2004-11-23 | 2005-05-25 | $7700.00 | Window Closed / Lapsed |