JPH07320550A - Impact resistant cable - Google Patents

Abstract

PURPOSE:To manufacture an impact resistant cable, eliminating necessity of a conduit tube for protecting an electric wire, by providing an impact resisting layer of specific thickness between an insulator and a sheath, in the electric wire, cable used in indoor wiring or the like. CONSTITUTION:In an electric wire, cable used in indoor wiring or the like, an impact resisting layer 3 of 0.2 to 1.4mm thickness is provided between an insulator 2 and a sheath 4, to provide a clearance of 0.2 to 2.6mm between the insulators 2. Further, the insulator 2 and the sheath 4 are formed of vinyl chloride resin composition, and the impact resisting layer 3 is formed of a composition compounding a vinyl chloride resin of 1000 to 2600 polymerization, vinyl chloride resin composition compounded with a plasticizer (dioctyl phthalate or the like) and a urethane resin of 50 shore A to 70 shore D hardness so that compound ratio of urethane/vinyl chloride resin composition is in a range of 20 to 70wt.% the urethane resin. In this way, an impact resistant cable, thinner than a concrete direct buried cable further with impact resistance equivalent thereto, is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to improvements in electric wires and cables used for indoor wiring and the like.

[0002]

2. Description of the Related Art In general, inexpensive vinyl-insulated vinyl sheaths are often used for electric wires and cables used for indoor wiring. Also, the trauma of vinyl insulated vinyl sheath cable,
As a cable with improved impact resistance, there is a cable for direct embedding in concrete.

[0003]

The vinyl of the vinyl-insulated vinyl sheathed cable is vulnerable to external damage and impact, and therefore, it has been laid in a conduit for the purpose of preventing it. However, the method of using an electric wire or the like has a drawback that it takes more time and labor than that of laying a cable alone, and the cost becomes higher. On the other hand, the cable for direct embedding in concrete may use a protective intervening layer containing a large amount of inorganic filler as shown in FIG.
It is difficult to extrude due to the use of cushioned floor cords like
Further, since the outer diameter is large, there is a problem that it is difficult to install.

[0004]

DISCLOSURE OF THE INVENTION The present invention provides an impact resistant cable that does not require a conduit for protecting an electric wire, is thinner than a concrete direct embedded cable, and has an impact resistance equivalent to that of the concrete direct embedded cable. To do. The feature is that a gap of 0.2 to 2.6 mm is provided between the core wires, and an impact resistant layer having a thickness of 0.2 to 1.4 mm is provided between the insulator and the sheath. The impact resistant layer has a urethane resin having a Shore A hardness of 50 to a Shore D hardness of 70, and a polymerization degree of 10
A vinyl chloride resin composition containing a vinyl chloride resin of 0 to 2600 and a plasticizer, and a urethane resin having a Shore A hardness of 50 to a Shore D hardness of 70 have a urethane / vinyl chloride resin composition blending ratio of 20 to 70 wt. % Composition, bound acrylonitrile amount 20-45% by weight
NBR rubber with a Shore A hardness of 50 to a Shore D hardness of 70
It is preferable to use a composition in which the urethane resin is a urethane / NBR rubber composition in the range of 20 to 70% by weight.

[0005]

By providing a gap of 0.2 to 2.6 mm between the core wires, the receiving area when a shock is applied can be increased and the shock can be softened. Further, the impact resistant layer having a thickness of 0.2 to 1.4 mm provided between the insulator and the sheath absorbs and repels impact, so that the impact resistance equivalent to that of the concrete direct buried cable is possible. The gap between the core wires is specified to be 0.2 to 2.6 mm because it is difficult to manufacture if it is less than 0.2 mm, and if it is 2.6 mm or more, the outer diameter becomes large and it becomes impossible to lay it, and the cable cost becomes too high. Because.

The thickness of the impact-resistant layer is specified to be 0.2 to 1.4 mm.
This is because the outer diameter becomes too large when it is more than mm. The gap between the core wires and the thickness of the impact resistant layer may be arbitrarily selected according to the outer diameter of the cable to be obtained. As a urethane resin,
Although general moldable urethane resins such as polyether type and polyester type were used, when the Shore A hardness is less than 50, the melting point of the urethane resin is low, and a bridge is easily generated at the hopper opening of the extruder, and further chlorination occurs. When used in a mixture with a vinyl resin composition or NBR rubber, the dispersibility was poor. On the other hand, Shore D hardness is 7
If it exceeds 0, extrusion processing becomes difficult because the melt viscosity is too high. Furthermore, when used in combination with a vinyl chloride resin composition or NBR rubber, at a temperature at which the vinyl chloride resin composition or NBR rubber melts, Since the urethane resin was not sufficiently melted, the dispersibility was poor.

Further, in the urethane / vinyl chloride resin composition or the urethane resin / NBR rubber composition, when the urethane resin content is less than 20% by weight, impact resistance is lowered.
On the other hand, when the urethane resin content exceeds 70% by weight, it becomes difficult to adhere to the insulating sheath. The vinyl chloride resin in the vinyl chloride resin composition in the urethane / vinyl chloride resin composition preferably has a polymerization degree of 1000 to 2600,
If it is less than 1000, the viscosity when melted is low, and if it is 2600 or more, the viscosity when melted is high, so that it cannot be uniformly mixed with the urethane resin in the extruder to be used by mixing with the urethane resin.

As the plasticizer, dioctyl phthalate, diethylhexyl phthalate, diisodecyl phthalate and other phthalic acid esters generally used for vinyl chloride, trioctyl trimellitate, triethylhexyl trimellitate and other trimellitic acid esters, 30 to 80 parts by weight of an adipic acid ester such as diisodecyl adipate, a pyromellitic acid ester, or a polyester plasticizer is used with respect to the vinyl chloride resin. As a plasticizer, it is desirable to add a large amount to soften it, but if 80 parts by weight or more is added to the vinyl chloride resin,
Since the solubility of the plasticizer in urethane was low, the plasticizer tended to bleed. On the other hand, if the amount is less than 30 parts by weight, the plasticizing effect of the vinyl chloride resin is insufficient, and the extruder cannot be uniformly mixed with the urethane resin.

Further, for the vinyl chloride resin composition, it is preferable to use a lead-based stabilizer, a barium-based stabilizer, a zinc-based stabilizer or the like alone or in combination in order to improve the thermal stability. Further, as a filler, calcium carbonate, clay, talc, magnesium carbonate, magnesium oxide, or the like, and a compounding agent such as a lubricant or a colorant that can be generally mixed with the vinyl chloride resin composition can be added. The NBR rubber in the urethane resin / NBR rubber composition has a bound acrylonitrile content of 20 to
It is preferably 45% by weight, and if it is less than 20% by weight or exceeds 45% by weight, it cannot be uniformly mixed with the urethane resin in the extruder. To the NBR rubber, it is possible to add calcium carbonate, clay, talc, magnesium carbonate, magnesium oxide or the like as a filler, and a compounding agent such as a lubricant or a colorant, which can be mixed with general NBR rubber.

[0010]

EXAMPLE A 2 × 1.6φ flat vinyl insulation vinyl sheath cable (hereinafter referred to as the new VVF FIG. 3) was made with the materials and structures shown in Tables 1 and 2, and the conventional 2 × 1.6φ flat vinyl insulation was used. Vinyl sheath cable (hereinafter, conventional VVF Fig. 7),
And a comparative test with 2 × 1.6φ flat concrete direct buried cable (hereinafter, CBVV), and the impact test results are shown in Tables 3 and 4. Impact resistance test is JIS C 3005 3
A weight of 5.0 kg was dropped while changing the height according to 0 impact. The AC breakdown voltage of the sample after the test was measured. The AC breakdown voltage was started from 1000 V, and the voltage was increased at a rate of 1000 V / min and measured up to 10000 V. In Examples 1 to 6 according to the present invention, there is no bleeding, the sheath and the insulator are adhered well, and the breakdown voltage is not lowered even after the impact test of 5 kg × 60 Cm. It can be seen that the characteristics are similar to those of the CBVV cable. On the other hand, Comparative Examples 1 to 14 are out of the specified range of the present invention, and Comparative Example 15 is a conventional VVF, but any one of the bleed, the adhesion to the sheath / insulator, and the impact resistance, or Inferior to several.

[0011]

[Table 1]

[0012]

[Table 2]

[0013]

[Table 3]

[0014]

[Table 4]

[0015]

As described above, according to the present invention,
It is possible to create an impact resistant cable that can withstand the same impact as a concrete direct-embedded cable without requiring a conduit for wire protection. It is considered that the electric wire cable produced according to the present invention is used in a wide range of fields such as replacement of a VVF cable for underfloor wiring of an apartment house, which has conventionally required an electric wire protection tube.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a sectional view of an embodiment of the present invention.

FIG. 3 is a sectional view of an embodiment of the present invention.

FIG. 4 is a sectional view of an embodiment of the present invention.

FIG. 5 is a cross-sectional view of a conventional cable for directly burying concrete.

FIG. 6 is a cross-sectional view of a conventional cable for directly burying concrete.

FIG. 7 is a sectional view of a conventional example.

[Explanation of symbols]

 1: Conductor 2: Vinyl insulator 3: Impact layer 4: Vinyl sheath 5: Protective intervening layer 6: Buffer cushion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshio Hagiwara 1-3-12 Moto-Akasaka, Minato-ku, Tokyo Sumitomo Electric Industries, Ltd. Tokyo Head Office (72) Inventor Kiyoyuki Seizo Shimaya, Konohana-ku, Osaka City, Osaka Prefecture 1-3 1 Sumitomo Electric Industries, Ltd. Osaka Works (72) Inventor Katsumi Imooka 2392 Iida, Hachihonmatsu-cho, Higashihiroshima-shi, Hiroshima Prefecture Kawamura Electric Wire Industry Co., Ltd. Hiroshima factory

Claims (5)

[Claims] 1. An impact resistant layer is provided between the insulator and the sheath in an amount of 0.2.
An impact resistant cable characterized by being provided with a thickness of up to 1.4 mm. 2. The method according to claim 1, wherein a gap between the insulators is 0.
A shock resistant cable having a gap of 2 to 2.6 mm. 3. The impact resistant layer has a Shore A hardness of 50 to Shore D.
The impact resistant cable according to claim 1, wherein a urethane resin having a hardness of 70 is used. 4. A vinyl chloride resin composition in which the insulator and the sheath are a vinyl chloride resin composition, and the impact resistant layer is a vinyl chloride resin composition containing a vinyl chloride resin having a polymerization degree of 1000 to 2600, a plasticizer and the like, and a Shore A hardness of 50 to Shore D. A urethane resin having a hardness of 70 is used, and a composition in which the compounding ratio of the urethane / vinyl chloride resin composition is in the range of 20 to 70% by weight of the urethane resin is used. Impact resistant cable. 5. The insulator and the sheath are made of a vinyl chloride resin composition, and the impact resistant layer has an amount of bound acrylonitrile of 20 to 45.
% Of NBR rubber and a urethane resin having a Shore A hardness of 50 to a Shore D hardness of 70 are used, and a composition in which the compounding ratio of the urethane / NBR rubber composition is in the range of 20 to 70% by weight of the urethane resin is used. The impact resistant cable according to claims 1 to 3.