RU213101U1 - OPTICAL INPUTS CABLE - Google Patents

Abstract

The utility model relates to cable technology, namely to optical input cables designed for external laying in the ground to the input point and internal laying from the input point to the end of the cable. The technical result consists in the creation of an input cable that simplifies installation work during laying due to the elimination of operations for splicing two cables. To do this, the optical subscriber cable on the part intended for outdoor laying is equipped with an intermediate rounded sheath made of polymer material located on top of the protective polymer sheath, on top of which there is a winding of power elements and an outer polymer sheath, while under the intermediate sheath there is a thread that provides opening of the intermediate sheath when cable cutting. To simplify the cutting, the cable contains a ripcord. Steel wires, or fiberglass rods, or aramidoplastic rods can be used as load-bearing elements of the cable. 3 w.p. f-ly, 4 ill.

Description

The utility model relates to cable technology, namely to optical input cables that can be used for outdoor laying in the ground or suspended on power lines of power lines and low-rise buildings to the input point and internal laying from the input point to the end of the cable.

Known combined design of an optical cable with a symmetrical four-pair cable (RU 2529208 C1, 09/27/2014), which is used in the public network. The optical cable structure contains optical fibers and two-pair symmetrical cable structures, each placed in a perforated polymeric tape separating each pair from each other. The combined design allows the use of a balanced pair in case of damage to the optical cable, ensuring the restoration of a damaged optical cable.

However, this design is very bulky, heavy due to the presence of symmetrical electrical pairs.

Fiber optic cables are known (RU 2540256 C2, 02/10/2015 and RU 133303 U1, 06/07/2013), containing at least one optical fiber in a dense polymer coating, identical straight longitudinal strength elements, an outer protective polymer sheath. To protect the optical fiber from crushing load acting perpendicular to the wide side of the outer cladding, the fiber is located between the power elements in a plane parallel to the wide side of the outer cladding.

However, such cables cannot be used when laying in an environment with extremely low and extremely high temperatures.

The closest analogue of the claimed technical solution is the optical cable described in the article "Optical drop cable", 05/29/2020 /vols.expert/useful-information/opticheskij-drop-kabel/, which is a GPON subscriber optical cable containing at least one optical fiber, identical straight longitudinal power elements, an outer protective polymeric sheath of rectangular cross section made of flame retardant material and containing two longitudinal grooves symmetrical with respect to the optical fiber on the outer sides, in places of its minimum thickness, allowing the fiber to be released by pushing the power elements to the sides. Butterfly-type subscriber optical cable is used for installation inside and outside buildings and structures, laying in special boxes.

This cable cannot be used for operation when laying in the ground up to the entry point, since it does not meet the requirements for optical cables for outdoor laying in the ground, in particular, in terms of mechanical and climatic characteristics.

In practice, two different optical cables are used, which are connected at the entry point by splicing optical fibers and installing a coupler, which leads to significant labor costs during installation.

The technical problem for which the claimed technical solution is intended to be solved is that it is required to develop a design for a subscriber optical input cable for laying in the ground up to the input point, in which the optical fibers along the entire length of the cable are continuous, uniform in optical, geometric and mechanical characteristics and do not contain splices of optical fibers.

The technical result of the utility model is to create an optical subscriber cable that meets the requirements both for cables for outdoor laying in the ground or suspended on power lines of power transmission lines, and for in-house cables, and which simplifies installation work during laying due to the elimination of splicing operations of two cables.

The specified technical result is achieved by the fact that the optical subscriber cable, intended for outdoor laying to the entry point into the room and internal laying from the entry point to the end of the cable, contains optical fibers, identical straight longitudinal power elements, parallel located along the optical fibers, rectangular in cross section protective a polymer sheath made of a flame retardant material and two longitudinal grooves symmetrical with respect to optical fibers on the outer sides, in places of its minimum thickness, ensuring the release of the fiber by pushing the power elements to the sides, while on the part of the optical cable intended for outdoor laying, it is equipped with a protective polymeric shell with an intermediate rounding shell made of polymeric material, on top of which there is a winding of load-bearing elements and an outer polymeric shell, while under the intermediate shell there is a thread that provides opening of the intermediate internal sheath when cutting the cable.

Steel wires, or fiberglass rods, or aramidoplastic rods can be used as load-bearing elements of the cable.

The essence of the utility model is illustrated by drawings, where:

in fig. 1 shows an optical subscriber input cable in a section in that part of it, which is located up to the point of entry into the room;

in fig. 2 shows an optical subscriber input cable in a section in that part of it, which is located after the point of entry into the room;

in fig. 3 shows the cable section at the entry point (side view);

in fig. 4 shows the entry of a subscriber cable into the room through a cable pit. The optical subscriber cable contains optical fibers 1, longitudinal strength elements 2, an outer protective polymer sheath 3 of rectangular cross section made of flame retardant material, a thread 4 is applied to the cable parts up to the entry point to open the intermediate sheath when cutting the cable, the so-called. ripcord, intermediate rounding sheath 5, winding 6 strength elements and outer sheath 7.

In FIG. 4 shows section 8 of the optical subscriber cable for intra-object laying in that part of it that is located after the entry point (without an intermediate rounding shell and armored cover from twisting power elements with an outer sheath), section 9 of the optical subscriber cable for outdoor laying in that part of it that is located up to the entry point (with an additional intermediate rounding shell, armored cover of stranded load-bearing elements and with an outer protective shell), as well as a cable pit 10.

Optical fiber 1 throughout its length is continuous and meets the requirements for both cables for outdoor laying, and for indoor. The optical fiber 1 is located parallel to the power elements 2, protecting the optical fiber 1 from damage. Fiberglass rods, aramidoplastic rods, or steel wires are used as load-bearing elements of the cable. The imposition of a layer of power elements is carried out on the armoring line, the imposition of polymeric cable covers on extrusion equipment. The protective polymer shell 3 is rectangular in cross section, on the wide part of the protective polymer shell there are two longitudinal grooves symmetrical with respect to the optical fiber 1 on the outer sides, in places of its minimum thickness, which allow the optical fiber 1 to be released by pushing the power elements to the sides.

The following are data confirming the industrial applicability of the utility model.

Flame retardant polymeric materials are polyvinylchloride compounds of the NG brand or thermoplastic polymers based on low-smoke, halogen-free polyolefins LSZH, with certain characteristics in accordance with the regulatory and technical documentation for them.

Manufacturing technology is traditional for this type of product.

Thus, the imposition of a layer of power elements is carried out on the armoring line, the imposition of polymeric cable covers on extrusion equipment. Fiberglass rods, aramidoplastic rods, steel wires are traditionally used as load-bearing elements of cable structures.

The cable can be produced in three steps. At the first extrusion operation, the full construction length is manufactured in accordance with the design documentation in the form of a "butterfly" subscriber optical cable with a protective polymer sheath of a rectangular cross section from a flame retardant material. In the second operation, a ripcord is added and an intermediate rounding shell is applied by the extruder on the section of the workpiece, which corresponds to the section of the outer gasket. At the third operation, on the section of the workpiece, which corresponds to the section of the outer lining, a layer of armored cover strength elements is laid over the intermediate shell and an outer protective polymer shell is applied by an extruder. The cable is wound on a shipping container so that the upper end (outer coils) are intended for indoor laying, unless otherwise provided by the installation project. The label of the drum and the accompanying documentation indicate information about the total length of the cable, and the lengths of the sections for outdoor and indoor laying. When laying (Fig. 4) through the cable pit 10, a cable section is pulled into the room for intra-object laying with a protective polymer sheath of rectangular cross-section from a flame retardant material, and the length of the cable section must exceed the length of the section route by 1-10 m for the possibility of subsequent switching work , excess cable is coiled indoors. A section of the cable for outdoor laying is laid in a trench from pit 10, and in pit 10 it is also recommended to make a bay with a margin of 1-10 m, which is usually provided for by the project. Reserve bays allow for repair work or cable laying with a slight deviation of the actual route from the design cable laying route.

The advantage of the claimed utility model is the ability to significantly simplify and reduce the cost of installation work by eliminating the operations of splicing two cables, since the proposed cable meets the requirements for both outdoor and indoor cables.

The undoubted advantage of the claimed utility model is also the possibility of using the existing "butterfly" subscriber cable fittings for installation and connection of a cable section without an intermediate sheath and twisting of power elements.

Claims (4)

1. Optical subscriber cable designed for outdoor laying to the point of entry into the room and internal laying from the point of entry to the end of the cable, containing optical fibers, identical straight longitudinal power elements parallel to the optical fibers, a protective polymer sheath made of material rectangular in cross section, flame retardant, and two longitudinal grooves symmetrical with respect to optical fibers on the outer sides, in places of its minimum thickness, ensuring the release of the fiber by pushing the power elements to the sides, characterized in that on the part intended for external laying, it is equipped with a protective polymer shell located on top an intermediate rounding sheath made of a polymeric material, on top of which there is a winding of power elements and an outer polymeric sheath, while under the intermediate sheath there is a thread that provides opening of the intermediate sheath when cutting the cable. 2. Cable according to claim 1, characterized in that steel wires are used as power elements. 3. Cable according to claim 1, characterized in that fiberglass rods are used as power elements. 4. Cable according to claim 1, characterized in that aramidoplastic rods are used as load-bearing elements.

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