Patent US4772435A successfully refreshed from Google Patents.
US4772435A
Expired / Lapsed
US
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Method of sheathing a fiber optic
Assignee: Maillefer SA
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Filing: 1985-12-03
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Granted: 1988-09-20
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Expires: 2005-12-03
Abstract
Abstract The optical fiber paid out from a reel passes through an extrusion head, then through a cooling vat, the sheath extruded around it being pulled by a withdrawal device. The sheath then passes through a second vat, when the stranding element is withdrawn by an auxiliary withdrawal device under as low a tension as possible. In the second vat, the stranding element is reduced to a temperature lower than the ambient temperature so that contraction of the sheath ensures the excess length of the optical fiber.
Inventors
- 👤 Rene Schlaeppi
- 👤 Remy Bruggmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:34
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/44; G02B6/4479; G02B6/4484; B; B29; B29C; B29C48/00; B29C48/03; B29C48/05
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
182 words
A method of producing a fiber optic stranding element, including the steps of passing a light-waveguide component through an extrusion head, forming in said extrusion head a protective sheath loosely encompassing said light-waveguide component and cooling said sheath, wherein the improvement comprises the steps of: pulling the sheath and the light-waveguide component together through the extrusion head and through a first cooling means while subjecting the light-waveguide component to a predetermined tensile stress; cooling the sheath and the light-waveguide component to a first temperature in said first cooling means; pulling said sheath and said light-waveguide component together from the first cooling means and passing them directly into and through a second cooling means while subjecting the sheath to a tensile stress as low as possible; maintaining the light-waveguide component free of tensile stress; cooling said sheath and said light-waveguide component in said second cooling means to a second temperature lower than said first temperature, thus enabling said sheath to shorten with respect to said light-waveguide component; and continuously taking up said fiber optic stranding element while pulling from said second cooling means.
Claim 2
Independent Claim
182 words
A method of producing a fiber optic stranding element, including the steps of passing a light-waveguide component through an extrusion head, forming in said extrusion head a protective sheath loosely encompassing said light-waveguide component and cooling said sheath, wherein the improvement comprises the steps of: pulling the sheath and the light-waveguide component together through the extrusion head and through a first cooling means while subjecting the light-waveguide component to a predetermined tensile stress; cooling the sheath and the light-waveguide component to a first temperature in said first cooling means; pulling said sheath and said light-waveguide component together from the first cooling means and passing them directly into and through a second cooling means while subjecting the sheath to a tensile stress as low as possible; maintaining the light-waveguide component free of tensile stress; cooling said sheath and said light-waveguide component in said second cooling means to a second temperature lower than said first temperature, thus enabling said sheath to shorten with respect to said light-waveguide component; and continuously taking up said fiber optic stranding element while pulling from said second cooling means.
Claim 3
Dependent Claim
24 words
The method of claim 1, wherein the cooling in the first cooling means is continued until a predetermined state of temperature equilibrium is attained.
Claim 4
Dependent Claim
48 words
The method of claim 1, wherein the cooling in the second cooling means is carried out in such a way as to cool the sheath to a temperature lower than the ambient temperature and lower than the temperature at which the finished stranding element is to be stored.
Claim 5
Dependent Claim
49 words
The method of claim 1, comprising the step of subjecting the light-waveguide component within the extrusion head and during the first stage of cooling to a degree of tensile stress sufficient to maintain the light-waveguide component taut within the sheath while keeping the elongation thereof within the elastic limit.
Claim 6
Dependent Claim
15 words
The method of claim 4, wherein the elongation of the light-waveguide component is substantially nil.
References Cited (Backward Citations)
US3055778A
Cited
US3728424A
Cited
DE2512371A1
Cited
US4154783A
Cited
US4078111A
Cited
US4089923A
Cited
DE2845887A1
Cited
EP0015425A2
Cited
US4414165A
Cited
US4458476A
Cited
US4583929A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-20 | 1992-03-21 | 1992-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-20 | 1996-03-21 | 1996-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-20 | 2000-03-21 | 2000-09-20 | $7700.00 | Window Closed / Lapsed |