Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B7/00—Insulated conductors or cables characterised by their form
  • H01B7/08—Flat or ribbon cables
  • H01B7/0869—Flat or ribbon cables comprising one or more armouring, tensile- or compression-resistant elements
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
  • H01B7/00—Insulated conductors or cables characterised by their form
  • H01B7/17—Protection against damage caused by external factors, e.g. sheaths or armouring
  • H01B7/18—Protection against damage caused by wear, mechanical force or pressure; Sheaths; Armouring
  • H01B7/182—Protection against damage caused by wear, mechanical force or pressure; Sheaths; Armouring comprising synthetic filaments
  • H01B7/183—Protection against damage caused by wear, mechanical force or pressure; Sheaths; Armouring comprising synthetic filaments forming part of an outer sheath

Definitions

• the present invention relates to a new telecommunications cable structure.
• a first type of cable is a cable which has an 8-shaped sheath, a first part of which is overmolded on a metal carrier and a second part of which defines a tube which receives a pair or a quarter of twisted copper wires.
• Such a structure has the drawback of being of considerable bulk and weight, as well as of a high cost.
• a second type of cable also known is a cable having a sheath of substantially flat shape inside which extend on the one hand a central metallic carrier and on the other hand, on each side of this carrier, pairs of copper wires.
• these cables like the cables at 8, have the drawback of requiring the metal carriers to be brought to earth at the level of the dwellings, in order to evacuate any lightning currents therein.
• Cables are also known of a structure similar to that proposed in US Pat. No. 4,467,138, but which comprise only a single pair of wires, the wires which constitute said pair being arranged on either side of the metal carrier. . Cables of this type are currently used as subscriber connection cable in France.
• cables have, in particular as regards their weight and cost, substantially the same drawbacks as cables with an 8 sheath or as cables of the type of those described in US 4,467,138.
• cables of the type as those described are also known. in US patents 4,761,053 and EP 0 468 689. These cables comprise carriers of dielectric material placed on either side of metallic conductors individually insulated by envelopes. These dielectric carriers and the insulated conductors are embedded in a plastic sheath which does not allow easy access to the conductors.
• the invention aims to overcome the problems posed by the various structures presented above by providing a cable capable of transmitting high frequency signals, which also allows to easily disassemble the conductors, while allowing good mechanical protection of those -this.
• a telecommunication cable and in particular a subscriber connection cable comprising a sheath, as well as two carriers made of a dielectric material and at least one pair of metallic wires which extend in said sheath, characterized in that said sheath has a central tube on either side of which the two carriers are arranged and inside which extends said pair of metal wires, the metal wires of said pair being twisted wires.
• the metal conductors - arranged in the tube - are not embedded in the sheath, which facilitates their disassembly relative to the rest of the sheath.
• the structure of the sheath allows the use of twisted conductor wires.
• this configuration advantageously makes it possible to limit the tensile stresses on the conductors - which is particularly important in the case of twisted conductors when it is desired to be able to reach high flow rates - and to transfer the stresses to the carriers in distributing them symmetrically with respect to the tube.
• the outside diameter of the central tube - that is to say its height - is less than the height of the sheath at the level of the carriers. This characteristic makes it possible to protect the conductors contained in the tube in the event of compression.
• FIG. 1 is a schematic representation in sectional view of a cable according to a first possible embodiment for the invention
• - Figure 2 is a schematic representation in sectional view of a cable according to a second possible embodiment for the invention
• FIGS. 3a and 3b are schematic representations in top view illustrating a type of fixing commonly used with subscriber cables. ;
• FIG. 4 is a representation similar to that of Figure 1 illustrating another possible embodiment of the invention.
• the cable of FIG. 1 comprises a sheath 1, which defines on the one hand a central tube 2 in which extends a pair of twisted metallic wires 6 or a quarter (that is to say a set made up of four twisted metallic wires ), and on the other hand two sub-sheaths 3 and 4 which are on either side of this central tube 2 and in which extend the carriers 5.
• the carriers 5 have the characteristic of being not of metallic materials but of dielectric materials.
• these carriers 5 are made of aramid wicks, or glass wicks.
• a carrier 5 made of glass wicks is for example a carrier 2 mm wide and 0.19 mm thick, capable of supporting 55 daN in traction.
• a carrier 5 made of aramid wicks would be of similar dimensions and mechanical characteristics.
• the twisted metal wires 6 are - in a manner known per se - insulated copper wires.
• these wires are for example of an external diameter between 0.4 and 0.8mm, an external diameter of 0.6mm being preferred.
• the insulation used for these copper wires is advantageously low density, medium density or high density polyethylene.
• the external diameter of the copper wires 6 with their insulator is between 0.65 mm and 1.30 mm, an external diameter of 0.96 mm being preferred (this preferred external diameter corresponding to the stripped external diameter of 0.6 mm indicated above).
• the twisted wires have an assembly pitch which can be constructed or which can be alternated (technique sZ).
• the pair of copper wires can be surrounded by an intermediate envelope (not shown) which provides thermal and / or mechanical protection.
• This envelope is for example constituted by a polyester ribbon with which the pair of wires 6 is surrounded.
• the sheath 1 is advantageously made of polyolefin.
• it is preferably made of PVC or polyethylene and more particularly preferably of high density polyethylene (density greater than 0.94), to satisfy the compatibility constraints with the insulation of the copper wires 6, as well as to satisfy the aging requirements.
• the central tube 2 has an internal diameter which corresponds substantially to the diameter of the twisted assembly formed by the metal wires 6.
• the central tube 2 is filled with a product 9, such as petroleum jelly, in which the wires 6 are embedded and which ensures or contributes to the sealing of the cable.
• a product 9 such as petroleum jelly
• petroleum jelly constitutes a non-frozen gel and therefore in no way imposes on the wires 6 constraints similar to those which would be imposed on said wires if they were embedded in a rigid material.
• This petroleum jelly does not prevent the easy stripping of the conductors for the preparation of the ends.
• the width of a cable conforming to such a structure (that is to say the distance between the most distant points of the sheath 3 and of the sheath 4) is 7.4 mm + 0.4 mm, while its height (i.e. its dimension perpendicular to the plane passing through the axes of the carriers 5 and the tube
• the sheath 1 has an elongation at break greater than 300%, the breaking force being greater than 18 MPa.
• the central tube 2 of the sheath 1 has a hexagonal external shape, while the sub-sheaths 3 and
• the central tube 2 and / or the sub-sheaths 3 and 4 can (be) be of round shape.
• the cable which has just been described is produced with the techniques conventionally known to those skilled in the art and in particular by extruding the sheath 1 on the carriers 5 and the metal wires 6.
• the sheath 1 may have another external shape than that shown in Figure 1 and in particular a shape of substantially rectangular section.
• the sectional shape shown in Figure 1 has the advantage of protecting the tube 2 and the pair of copper wires 6 therein against compression forces.
• the height of the sub-sheaths 3 and 4 is greater than that of the tube 2.
• the tube 2 is located between the two planes which are tangent to the two sub-sheaths 3 and 4 and is therefore protected against compression forces. acting on the cable perpendicular to the plane passing through the axes of the carriers 5 and the central tube 2.
• They comprise a sheath 8 in which the cable C is engaged in a loop and a part 7 forming a corner which is then pressed into the sheath and which comes to bear on the edges of the cable.
• the zones by which the tube 2 is connected to the sheaths 3 and 4 are preferably of a height I less than the minimum thickness e of the tube 2.
• Such zones thus define the tear-off tabs which make it possible to simply tear the two sheathed carriers of the central part so as to access, without special tools, the pair of metal wires.
• these tear tabs are less than 0.4 mm high.
• non-metallic carriers allows greater lightness of structure, as well as an optimized cost.
• the proposed cable can be drawn inside the dwellings, unlike the connection cables known to date.

Landscapes

• Communication Cables (AREA)
• Insulated Conductors (AREA)
• Interface Circuits In Exchanges (AREA)
• Multi-Conductor Connections (AREA)
• Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8846914

Family Applications (1)

Country Status (12)

Families Citing this family (1)

Citations (2)

• 2000
  • 2000-02-11 FR FR0001728A patent/FR2805096B1/fr not_active Expired - Lifetime
• 2001
  • 2001-02-09 ES ES01907752T patent/ES2228811T3/es not_active Expired - Lifetime
  • 2001-02-09 PT PT01907752T patent/PT1177561E/pt unknown
  • 2001-02-09 AU AU35643/01A patent/AU3564301A/en not_active Abandoned
  • 2001-02-09 OA OA1200100256A patent/OA11925A/fr unknown
  • 2001-02-09 EP EP01907752A patent/EP1177561B1/de not_active Expired - Lifetime
  • 2001-02-09 DZ DZ013143A patent/DZ3143A1/xx active
  • 2001-02-09 TN TNTNSN01023A patent/TNSN01023A1/fr unknown
  • 2001-02-09 WO PCT/FR2001/000386 patent/WO2001059792A1/fr active IP Right Grant
  • 2001-02-09 DE DE2001606345 patent/DE60106345D1/de not_active Expired - Lifetime
  • 2001-02-09 AT AT01907752T patent/ATE279777T1/de not_active IP Right Cessation
  • 2001-10-11 MA MA26353A patent/MA25350A1/fr unknown

Patent Citations (2)

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