RU2705358C1 - Symmetrical four-pair cable with film milli insulating cord - Google Patents

Abstract

FIELD: electrical engineering.

SUBSTANCE: invention relates to electrical engineering and can be used in makeups of symmetric communication cables within a shared network or structured cable systems. Symmetric four-pair cable contains strands in film-polymer insulation, twisted into pairs with different pitching strands, with outer polymer shell, characterized by that in order to reduce relative dielectric permeability of cable strands insulation, reduction of steam capacity and, consequently, dielectric losses and capacitance component of the effect between pairs, insulation of each conductor is made in the form of equal-sized milli insulating cords, wherein distances between milli insulating cords correspond to diameter of milli insulating cord along the entire section of each conductive core, and the external film insulation is in contact with milli insulating cords in the entire section of each conductor along the entire length of the symmetrical cable. Equivalent relative dielectric permeability of current conductor insulation is equal to 1.9.

EFFECT: as a result, attenuation coefficient decreases due to reduction of losses in insulation of conductors and capacitive component of influence between pairs.

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Description

The invention relates to the field of electrical engineering and can be used in the construction of symmetric communication cables on public networks and structured cable systems.

In symmetric communication cables on public networks and structured cable systems, different types of cable core insulation are used depending on the category: for cable core strands, polyethylene with a relative dielectric constant of 2.3 is used as insulation core; for category 3 cables, a dielectric material is used for insulation of cores also with a relative permittivity of 2.3; for cables of category 5e and above, cellular polyethylene with a sheath is used as insulation - film-porous polyethylene with a relative dielectric constant of 2.0; Category 6 cables use Teflon core insulation with a relative dielectric constant of 2.0.

A known design of a four-pair cable containing copper conductors in dielectric insulation, twisted in pairs with different pitch, in a common external dielectric sheath ("Structured cable systems" authors: AB Semenov, SK Strizhakov, IR Sunchely, DMK Publishing House, M. 2002, 4th edition, p. 109, Fig. 3.4 and 3.5). The disadvantage of this design is the relatively high value of the relative permittivity of the insulation of the cable conductors.

A known design of a four-pair cable, consisting of two fours, twisted of two pairs of each four, with film-porous insulation of conductors and an external polymer sheath ("Structured cable systems" authors: AB Semenov, SK Strizhakov, I. R Sunchely, DMK publishing house, M. 2002, 4th edition, p. 106, Fig. 3.2 b). The disadvantage of this design is also the high value of the relative dielectric constant of the insulation of the cores.

The proposed solution closest in technical essence is the four-pair cable design described in the prospectus of Teldor, Wires and Cables, Russia Ltd. 2006, 223 pp., P. 35 (website: www.teldor.com). The cable is designed for indoor stationary laying, consists of four unshielded twisted (twisted) pairs twisted together, protected by a PVC sheath; core diameter 0.51 mm, polyolefin insulation (film-porous film insulation, insulated core outer diameter 0.9 mm; cable outer diameter 5.0 mm). Given the maximum signal propagation speed equal to 0.7 of the speed of light, the relative dielectric constant of the core insulation is 2.0, which is also the main disadvantage of this cable.

The technical result, which this technical solution is aimed at, is to create a design of a symmetrical four-pair cable, which allows to reduce the relative dielectric constant of the cable cores insulation.

To achieve a technical result in a symmetrical four-pair cable containing conductive conductors in film-polymer insulation, twisted into symmetrical pairs with different twisting steps into a common twist, with an external polymer sheath, the insulation of each conductive core is made in the form of millicordes of the same size over the entire cross section of each conductive veins, while the distance between the millikordel corresponds to the diameter of the millikordel over the entire cross section of each conductive core, and the outer film insulation is in contact I with millikordels of each conductive core across the entire section of each conductive core along the entire length of the balanced cable. Millicordels have the same diameter, and the outer film insulation is in contact with millicordels of each conductive core over the entire cross section of each conductive core along the entire length of the symmetrical cable.

In addition to achieving the main technical result, a reduction in dielectric loss and capacitive component of the effect between the pairs is achieved.

In FIG. 1 shows the design of a symmetrical four-pair cable with a film of millicorelle insulation of conductors, where

1 - symmetric pair;

2 - conductive core;

3 - millichordels;

4 - external film insulation;

5 - outer polymer shell.

The design of a symmetrical four-pair cable with a film of millicordal insulation of conductors contains symmetrical pairs 1, conductive conductors 2 with millicord 3, external film insulation 4 in contact with millicord insulation 3, and an outer polymer sheath 5. In FIG. 2 shows an enlarged design of a symmetrical pair 1. It contains a conductive core 2, millikordels 3 over the entire cross section of the conductive core, an outer film insulation 4 in contact with millikordels 3 over the entire cross section of the conductive core 2 over the entire length of the symmetrical cable 5.

In the design of a symmetrical four-pair cable, a cable core of four symmetric pairs 1 is located inside the outer polymer sheath 5. The insulation of each conductive core 2 is made in the form of millicordels 3 located along the entire cross section of each conductive core 2. The distance between the millikordels corresponds to the diameter of the millikordel 3 over the entire cross section of each conductive core 2, and the outer film insulation 4 is in contact with insulation based on millicordeles 3 of each conductive core throughout the entire section of each conductive dyaschey conductor 2 over the entire length of a balanced cable.

The use of the proposed film of millicordal insulation significantly reduces the relative dielectric constant of the insulation of conductive wires due to the fact that millikordeli 3 do not fill the entire space between the conductive core 2 and the outer film insulation 4. The relative dielectric constant of the medium between millikordel 3 and the outer film insulation 4 of the core is 1.0 (relative dielectric constant of air is 1). Depending on the number of millicordels 3, it is possible to change the relative permittivity in a wide range, thereby reducing losses in the dielectric. When the distance between millikordely 3, equal to the diameter of millikordely 3, we obtain the relative dielectric constant of the entire insulation of the conductive core 1, equal to 1.9.

Thus, a decrease in the relative dielectric constant of the cable cores is achieved. As a result, the attenuation coefficient decreases due to a decrease in losses in the insulation of the cores and the capacitive component of the effect between the pairs.

Claims (1)

A symmetric four-pair cable containing conductive conductors in film-polymer insulation, twisted into symmetrical pairs with different twisting steps into a common twist with an external polymer sheath, characterized in that the insulation of each conductive core is made in the form of millicordes of the same size over the entire cross section of each conductive core, the distances between the millikordely correspond to the diameter of the millikordel over the entire cross section of each conductive core, the outer film insulation is in contact with the millikordely second electrical conductor over the entire section of each conductor along the entire length of symmetrical cable millikordeli have the same diameter, and the outer insulation film in contact with each millikordelyami conductor around each conductor section over the entire length of symmetrical cable.

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