FR2495334A1 - IMPROVED BODIES CONTAINING ELEMENTS FOR FIBER OPTIC TELECOMMUNICATIONS - Google Patents

Abstract

The invention relates to improvements made to overhead power conductors or overhead earth cables containing optical fibers. According to the invention, these conductors or cables 10 are produced with at least one ring of electrically conductive and mechanically resistant elements 18, 20 formed by self-supporting elongate bodies 19 which preferably have the shape of keystones. Application to telecommunications. (CF DRAWING IN BOPI)

Description

The present invention relates to improvements made to

  elongate suspended bodies which may be both overhead power conductors and overhead earth cables which contain one or more optical fibers. The expression "containing one or more optical fibers" is understood to mean the case where the elongated bodies intended to be suspended contain either at least one or more fibers, which are bare or covered with at least one primary coating, or at least one fiber telecommunications cable

  optics, or one or more elements of telecommunica-

  fiber optic cable or covered at least with the coating

  primary education and provided individually or as a whole

at least one protection.

  It is known that, by analogy with what is already done with coaxial pairs, it is expected since

  long time to house fiber optics inside the con-

  Power overhead conductors and overhead earth cables.

  The state of the art is shown, for example, in British Patent Application GB 2,029,043, in which the optical fibers are loosely arranged.

  inside an aluminum conductive tube, which is

  with strong and conductive cylindrical elements, the conductors and the resistant elements being made of metals or metal alloys different from each other.

  The Applicant describes notable improvements

  in the state of the art in both applications for

  Italian vests 25,006 A / 80 and 25,071 A / 80. In these requests,

  described are power overhead conductors and

  airborne earth conductors comprising a tubular conductive element

  water tight, surrounded by layers of elongated elements

  resistant and conductive thus constituting an anti-assembly

  torsion and electrochemically stable.

  In the longitudinal cavity of the tubular conductor are housed, in the first case, one or more optical fibers and, in the second case, at least one

  optical fibers, or one or more telecommunication elements

  communication comprising one or more optical fibers of which

  the assembly is surrounded by at least one protective element.

  The Applicant has found that the elongate bodies known until now and those described in both

  aforementioned requests may be subject to improvement.

  Indeed, in the current formulations of acriens power conductors and overhead cables, great care is taken in the production and handling to avoid that, under the effect of external stresses, the tubular conductor élémrnt does not collapse in

  invading the star interstices that separate the fibers.

  In this case, the metal could, in turn,

  deform or break down the fibers or telecom-

  iaunications contained in the driver.

  In addition, according to the state of the art,

  the manufacture of overhead power or power cables, appropriate precautions should always be taken to protect the fibers or telecommunications

  high temperature extrusion fibers of the element con-

  tubular conductor or welding temperatures if the conductor

  The tubular core is formed of a welded longitudinal ribbon.

  It is also necessary to take a

  particular care in the choice of the material forming the con-

  tubular conductor, so that this material is electrochemically compatible with the elongated resistant elements and

  the elongate conductive elements of the crown or necks

  surrounding this conductor, as described in the Italian patent application N 25 006 A / 10 in the name of the

Applicant.

  According to the present invention; the Applicant proposes power overhead conductors or aerial cables "containing optical fibers" that overcome the above-mentioned disadvantages and accelerate their production, eliminating the need to employ special precautions or to take certain precautions during the

  different operations to which those conductors

transducers.

  In particular, the overhead conductors of

  or the aerial ground cables according to the invention are of construction and easy handling, thanks to the fact that they are

  free from the risk of collapse of possible tubular elements

  metallic wires. In addition, during the production of aerial cables or overhead power conductors

  The invention will not achieve the high temperatures of

  trusion or welding normally achieved for production

  of tubular metal conductors.

  Furthermore, according to this application, it is not

  it is no longer necessary to strictly observe the elec-

  trochemical, which is imposed by the tubular conductive element

  lar. More specifically, the subject of the invention is a

  elongated body intended to be suspended, containing one or more

  sieurs optical fibers, which are enclosed in the longitudinal cavity of a tight closed tubular element, surrounded by at least one ring of electrically conductive elongated elements and mechanically resistant elongated elements. The electrically conductive elements and the mechanically resistant elongate elements constitute an anti-torsion assembly. The elongated body is characterized in that the sealed tubular member is formed of a non-metallic material, and at least one elongate member ring is constituted by self-supporting members. According to a preferred embodiment, the self-supporting elements are in the form of keys of voce ("conci" in Italian).

  advantageously, these elements are electro-

  conductors and constitute the crown that directly surrounds

  the tubular non-metallic tubular element.

  According to another preferred embodiment

  In accordance with the invention, this non-metal sealed tubular element

  It is made of a thermoplastic material.

  The following description, which does not present

  any limiting character must be read in conjunction with the

  annexed which represents a cross-section of a

  practical embodiment of the invention.

  As can be seen in this figure, the elongated cylindrical body 10 intended to be suspended may constitute either an overhead power conductor or an overhead ground cable, this conductor or cable containing

one or more optical fibers.

  The elongate body 10 contains, according to the embodiment shown in the figure, a single optical fiber 11 surrounded by a first sheath 12 of silicone, and a second sheath 13 of polyamide. The sheaths 12 and 13 are

  adherent to each other and also adhere to the fiber-l1.

  The fiber 11 with its sheaths 12 and 13 constitutes

  a telecommunication element 14. This element is

  loosely contained in a protective sheath 15.

  The entire telecommunication element 14, with its protective sheath 15 constitutes what can be

  call a telecommunication cable 16.

  The telecommunication elements combined in one cable could also be greater than one and each could also contain more than one optical fiber. The sheaths of protections could also be in number greater than one, luches and / or adherent with respect to the element or elements for telecommunications

  and could be made from any of the following

  proprieties, which may be, for example, but not

  necessarily extruded plastics or

  wrapped banners and / or paper. In other words, the protective sleeves could be of any known type

  in the field of fiber optic telecommunications.

  In this way, the sheaths surrounding the fiber or the optical fibers could be one or more than one; they could be adherent or isolated

  and could be in any suitable material.

  The cable 16 is enclosed in the cavity 22

  longitudinally of the tubular element 17 waterproof, non-metallic

  lic. This tubular element 17 is preferably, but not necessarily, constituted by a thermoplastic material such as

  that, for example, a compact or expanded polyolefin or

  core a combination of such polyolefins.

  The tubular element 17 could also be made of a plastic material or an elastomer modified by any process of crosslinking in order to improve their properties.

  thermal or mechanical performance.

  The Applicant has observed that it is particularly

  to use for the realization of the

  It is thus possible to withstand thermal stresses such as those which can be observed, for example, in the case of overheating due to the fall of the lightning. It has proved equally effective to use judiciously vulcanized silicone elastomers. The tubular element 17 may also comprise not a single layer but several adherent layers between them and also materials which differ from each other either by their chemical constitution or by their physical characteristics. The tubular element 17 is

  preferably formed by extrusion.

  Around this tubular element 17, non-metallic

  lique, is a first crown or a first helicoid-

  18 composed of electro-conductive elongate elements

  19 having self-supporting characteristics.

  Here we mean by self-supporting characteristics the characteristics

  of a structure that gives elongated elements

  the possibility of cooperating with each other by avoiding

  tion, phenomena which could cause, in particular, a radial collapse towards

inside. -

  In the preferred embodiment

  in the figure, the elongated

  The self-supporting conductors 19 have the typical structure known in the art as the keys of your choice.

("conci" in Italian).

  These 13emerns 19 have the shape of circular sectors, the first ring 18 is surrounded by second ring urn

  outer helical wire 20 made of elongated mechanical

  21, which are cylinders in this embodiment of the invention. The inner hdlicoide 18 and the outer helicoid

  preferably constitute an anti-torsion assembly. natu-

  the case where it would be preferable

  rable, to make the outer helicoúde 20, instead of

  inner side 18, with self-supporting elements or to realize the two helicoids with self-supporting elongated elements. These helicoidal elongated elements can be

  one or more than one. In an extreme case, we

  should have a single helicoid, comprising elements allon-

  mechanically resistant self-supporting and / or electrically

conductors.

  The figure, which represents an example of reali-

  tion, refers to the case in which the cavity 22

  the non-metallic tubular element 17 contains at least one cable 16 loosely housed; but it is obvious that the invention also applies to the case in which the

  outer diameter of the cable 16 is equal to or greater than

  sence of a tightening) to the inside diameter of the tubular

water 17 non-metallic waterproof.

  It would also be possible, in the cavity 22 of the non-metallic tubular element 17, to replace, in the place of a cable, one or more fibers that are bare or provided with their only primary coating or one or more communication elements without a tubular element. protection, so

loose or not.

  It should be noted another advantage of the

  present invention, which consists in adopting a tubular element

  non-metallic watertight membrane 17, namely that it is possible to

  the need to protect the fibers inside the

  tubular element 17, since a tuft element is used.

  non-metallic waterproof bung 17 according to the present invention.

Claims (10)

  1. Elongated body intended to be suspended, containing one or more optical fibers, said optical fibers being enclosed in the longitudinal cavity (22) of a tubular element (17) sealed which is surrounded by at least   a ring of elongated electroconductive elements and ele-   mechanically resistant elongated elements, said elements   electrically conductive lanyards and said elongated   substantially resistant forming an anti-torsion assembly,   an elongate body characterized in that said tubular member   water-resistant sleeve (17) is made of a non-metallic material, and that one of said elongated element rings (18, 20) being   constituted by self-supporting elements (19).   2. The elongated body according to claim 1, characterized in that said self-supporting elements (19) have the shape of keystones.   3.- Elongated body according to one of the claims   1 and 2, characterized in that said self-supporting elements   carriers (19) are electrically conductive.   4. Elongate body according to one of the claims   2 and 3 characterized in that said elongated elements self-   carriers (19) constitute the crown (18) which surrounds   said tubular member (17) sealed non-metallic.   5. Elongated body according to any one of   preceding claims, characterized in that said ele-   Non-metallic sealed tubular member (17) is made of a thermoplastic material.   6. Elongated body according to one of the claims   previous arrangements, characterized in that said tubular element   non-metallic water-resistant membrane (17) is made of abutment. -   7. Elongated body according to claims 5   and 6, characterized in that said thermoplastic material is a polyolefin.   8. Elongate body according to claim 7,   characterized in that said polyolefin is polyethylene.   9. Elongate body according to any one of   Claims 1 to 4, characterized in that said element   tubular (17) nonmetallic waterproof is made of an elastomeric material. An elongate body according to claim 9, characterized in that said elastomeric material is a   silicone elastomer which is advantageously vulcanized.