JP2010010091A - Communication cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication cable with alien crosstalk countermeasures and with concentric cross section for a minimum cross-section area, a simple structure and low manufacturing cost. <P>SOLUTION: The communication cable includes: a twisted pair of wires 4 where two single wires 3 are stranded each composed of a conductor 1 with an outer perimeter covered with an insulator 2; a divider 5 with a cross section 'cross'-shaped, isolating four pieces of twisted pairs of wires 4 by barrier ribs; an internal sheath 7 composed of a foaming polyethylene covering the four pieces of twisted pairs of wires 4; and an outer sheath 8 to cover the inner sheath 7. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication cable used as, for example, a 10 GBASE-T standard UTP (Unshielded Twisted-Pair) LAN cable.

  10GBASE-T is a 10Gbit / s Ethernet (registered trademark) standard that uses a copper LAN cable. In June 2006, the 802.3 standardization group of IEEE (American Institute of Electrical and Electronics Engineers) It was enacted. This standard conforms to the 10 GbE transmission system for UTP (Unshielded Twisted-Pair) cable of Category 6 or higher. The transmission distance is 55 m for Category 6, Augmented Category 6 and Category 7 Then it is 100m. The transmission frequency is 250 MHz for category 6, 500 MHz for augmented category 6, and 600 MHz for category 7.

  Conventionally, as a data transmission communication cable (LAN cable), etc., a cross-sectional shape composed of polyethylene, etc., with four twisted wires twisted together with two insulated core wires (single wires) with an insulation coating on the outer periphery of the conductor Is disclosed in, for example, Patent Document 1 and the like, which are arranged between partition walls of a cross-shaped threshold plate (partition member), twisted together and covered with an insulating sheath.

  According to this communication cable, the four twisted wires are separated from each other in the circumferential direction by the threshold plate, so that the crosstalk characteristic generated between the twisted wires is improved, and the return loss and the characteristic impedance are also improved. Improved.

  Normally, in a communication cable wiring system, a single communication cable is not laid alone, but a plurality of communication cables are laid in a multiple manner so as to be adjacent to each other. In this case, crosstalk (alien crosstalk) between communication cables having a high transmission frequency such as 10GBASE-T standard has become a problem.

  In order to reduce such alien crosstalk, conventionally, a polyethylene cordel string is spirally wound to hold the entire four twisted pairs, and the outer circumference is A communication cable covered with an insulating sheath and a communication board having a cross-shaped cross section with different vertical and horizontal lengths and having a cable shape that is elliptical have been developed (for example, FIG. 4 of Patent Document 2). However, in both cases, the cable cross section is not a concentric circle but an irregular one.

As described above, the conventional communication cable has a problem in that it is difficult to handle due to its complicated structure, and the manufacturing price is expensive.
Japanese Patent Laid-Open No. 11-053958 Japanese Patent Application Laid-Open No. 2008-97872

  The present invention has been made to solve the above-mentioned conventional problems, and its purpose is a communication cable that is excellent in handleability, has a simple structure, and can be manufactured at low cost with anti-alien crosstalk countermeasures. Is to provide.

  The communication cable of the present invention has a cross-shaped cross-sectional shape in the direction perpendicular to the longitudinal direction, and a pair of twisted wires in which two conductors whose conductors are covered with an insulator are twisted together. A partition member made of an insulating material that separates the stranded wires from each other by a partition; a first jacket that is made of foamed polyethylene and is provided so as to cover the four twisted wires; and And a second outer cover made of an insulating material provided to cover the outer cover.

  The communication cable of the present invention has a cross-shaped cross-sectional shape in the direction perpendicular to the longitudinal direction, and a pair of twisted wires in which two conductors whose conductors are covered with an insulator are twisted together. A partition member made of an insulating material that separates the stranded wires from each other by partition walls, a first jacket made of an insulating material provided so as to cover the four pairs of twisted wires, and a foamed polyethylene. And a second outer cover provided to cover the first outer cover and a third outer cover made of an insulating material provided to cover the second outer cover. It is characterized by that.

  According to the present invention, a concentric cross-section can be obtained, the structure is simple and the cross-sectional area can be minimized, and therefore, when a connector is attached to the cable, termination can be easily performed, and It is possible to provide a communication cable that can be manufactured at low cost and that is designed to prevent alien crosstalk.

  The present invention will be described below with reference to the drawings.

<First Embodiment>
FIG. 1 shows a cross-sectional structure when the UTP cable according to the first embodiment is cut in a direction orthogonal to the longitudinal direction. The communication cable of the present embodiment has four pairs of twisted wires 4 in which two single wires 3 in which the outer periphery of the conductor 1 is covered with an insulator 2 are twisted together. Furthermore, the cable of the present embodiment has a cross-sectional shape in a direction orthogonal to the longitudinal direction, and a partition plate (for example, a plastic made of an insulating material that separates the four twisted wires 4 from each other by partition walls ( Partition member) 5. The partition plate 5 suppresses crosstalk between the paired twisted wires 4 in the cable. The four twisted wires 4 separated from each other by the partition plate 5 are twisted together and covered with an inner sheath (first jacket) 7 made of foamed polyethylene. Further, an outer sheath (second jacket) 8 made of an insulating material is provided so as to cover the inner sheath 7.

  The foamed polyethylene used for the inner sheath 7 is a material generally used for coaxial cables and the like, is very lightweight, and has excellent flexibility (easy to bend).

  According to the communication cable of the present embodiment, by providing the inner sheath 7 made of foamed polyethylene, when a plurality of communication cables are bundled and laid in multiple forms, the distance between the pair of twisted wires 4 is increased between adjacent cables. The alien crosstalk characteristics can be improved. Moreover, since the inner sheath 7 made of foamed polyethylene is provided, the communication cable can be prevented from being crushed and damaged even when pressed by an excessive external pressure. Since the foamed polyethylene used for the inner sheath 7 is excellent in flexibility, it can be easily laid on the corners as in the case of the conventional cable.

  Here, when the communication cable of the first embodiment has the same outer diameter as that of the conventional one, the thickness of the inner sheath 7 made of foamed polyethylene can be sufficiently increased. The crosstalk characteristic can be further improved.

  Further, the cable of the present embodiment can have a concentric cross section, and the structure is simple and the cross sectional area can be minimized. For this reason, when attaching a connector to the terminal of the said cable, termination processing can be performed easily. In addition, when attaching a connector, when peeling off the outer sheath 8, it can respond easily by peeling off the inner sheath 7 simultaneously.

  Further, since the communication cable of the present embodiment has a simple structure, it can be easily manufactured, and therefore can be manufactured at low cost.

<Second Embodiment>
FIG. 2 shows a cross-sectional structure when the UTP cable according to the second embodiment is cut in a direction orthogonal to the longitudinal direction. The communication cable of the present embodiment has four pairs of twisted wires 4 in which two single wires 3 in which the outer periphery of the conductor 1 is covered with an insulator 2 are twisted together. Furthermore, the cable of the present embodiment has a cross-sectional shape in a direction orthogonal to the longitudinal direction, and a partition plate (for example, a plastic made of an insulating material that separates the four twisted wires 4 from each other by partition walls ( Partition member) 5. The partition plate 5 suppresses crosstalk between the paired twisted wires 4 in the cable. The four pairs of twisted wires 4 separated from each other by the partition plate 5 are twisted together and covered with a first inner sheath (first jacket) 6. Further, a second inner sheath (second jacket) 7 made of foamed polyethylene is provided so as to cover the first inner sheath 6. Furthermore, an outer sheath (third jacket) 8 made of an insulating material is provided so as to cover the second inner sheath 7.

  Also in the communication cable of this embodiment, the effect similar to the thing of 1st Embodiment is acquired.

  FIG. 3 shows measured values of alien crosstalk characteristics when a plurality of communication cables according to the first and second embodiments are bundled and laid and wired (crosstalk between four pairs of different cables: Pair1 ~ Pair4) is shown together with standard values. The standard value of alien crosstalk in a 10GBASE-T category 6A communication cable is 62.5 dB or more at 100 MHz and 52.0 dB or more at 500 MHz in terms of power sum near-end crosstalk attenuation (PSANEXT) between cables. As shown in FIG. 3, it can be understood that the communication cables of the first and second embodiments sufficiently satisfy this standard value.

Sectional drawing of the communication cable which concerns on 1st Embodiment. Sectional drawing of the communication cable which concerns on 2nd Embodiment. The characteristic view which shows an example of the alien crosstalk characteristic of the communication cable of 1st, 2nd embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Conductor, 2 ... Insulator, 3 ... Single wire, 4 ... Pair twisted wire, 5 ... Partition plate (partition member), 7 ... Inner sheath, 8 ... Outer sheath.

Claims (2)

A twisted pair of two single wires in which the outer periphery of the conductor is covered with an insulator;
A cross-sectional shape in a direction perpendicular to the longitudinal direction forms a cross shape, and a partition member made of an insulating material that separates the four twisted wires from each other by a partition;
A first outer jacket made of polyethylene foam and provided to cover the four twisted wires;
A communication cable, comprising: a second jacket made of an insulating material provided to cover the first jacket. A twisted pair of two single wires in which the outer periphery of the conductor is covered with an insulator;
A cross-sectional shape in a direction perpendicular to the longitudinal direction forms a cross shape, and a partition member made of an insulating material that separates the four twisted wires from each other by a partition;
A first jacket made of an insulating material provided to cover the four pairs of twisted wires;
A second envelope made of polyethylene foam and provided to cover the first envelope;
A communication cable, comprising: a third jacket made of an insulating material provided to cover the second jacket.

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