JP2018152249A - Cable with shield layer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cable with a shield layer capable of suppressing lowering of electromagnetic shielding characteristics even when bending is repeatedly applied thereto.SOLUTION: A cable with a shield layer includes a first shield layer and a second shield layer which are brought into contact with each other between at least one electric wire and a sheath covering the whole electric wire, where the first shield layer is a resin composition for electromagnetic wave shielding, and is provided between the electric wire and the second shield layer so as to cover the electric wire, and the second shield layer is a conductive fabric and is provided between the first shield layer and the sheath so as to cover the first shield layer.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cable with a shield layer.

  In recent years, electric vehicles have been developed that run using electricity as an energy source and an electric motor as a power source. Since such an electric vehicle needs to be charged, a charging facility such as a charging station or a charging station, or a charging facility provided in a home or office is required. For example, the charging station is provided in a public space facing a public road, and rapidly charges an electric vehicle with, for example, three-phase 200V and an output of about 50W.

The charging stand includes, for example, a charging stand body, a charging cable, and a charging connector. When the user performs charging himself / herself at the charging stand, for example, the user grasps the charging connector, removes the charging cable wound around the main body, and then inserts the charging connector into the power supply port of the automobile.
As a quick charging standard for electric vehicles, for example, there is CHAdeMO (registered trademark) established by the CHAdeMO (registered trademark) Council. A charging cable according to this standard includes, for example, two power lines, a plurality of communication lines, a ground line, and a sheath.

  The length of the charging cable is, for example, about 5 to 7 m. Since the charging cable is pulled out every time it is used for charging, flexibility, durability, handling, and the like are required. Also, in the charging cable, the maximum output as of 2016 in CHAdeMO (registered trademark) is 125 A, but there is a demand for a maximum output such as 250 A.

  Such a high-voltage cable or the like is required to have an electromagnetic shielding property. For this reason, in such a cable, the power line is surrounded by a metal material. When the cable is repeatedly bent, the metal material for shielding the electromagnetic wave is cracked, and the electromagnetic wave shielding characteristic is deteriorated. For this reason, it has been proposed to use a resin-based shielding material obtained by mixing a resin with a metal material as an electromagnetic shielding material (see, for example, Patent Document 1).

JP 2005-235409 A

  However, in the technique described in Patent Document 1, cracks may occur in the resin-based shielding material due to repeated bending, and the sheath may also crack due to the influence. As described above, when a crack occurs in the resin-based shielding material or the sheath, the electromagnetic shielding property is deteriorated, and the electromagnetic wave generated from the cable may leak to the outside, or the external electromagnetic wave may affect the signal line of the cable. there were.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a cable with a shield layer that can suppress a decrease in electromagnetic wave shielding characteristics even when bending is repeatedly applied.

[1] In order to achieve the above object, a cable with a shield layer according to an aspect of the present invention includes a first shield layer and a second shield layer that are in contact with each other between at least one electric wire and a sheath that covers the entire electric wire. A shield layer, wherein the first shield layer is an electromagnetic wave shielding resin composition, is provided between the wire and the second shield layer so as to cover the wire, and the second shield layer is A conductive cloth is provided between the first shield layer and the sheath so as to cover the first shield layer.

[2] In the cable with a shield layer according to one aspect of the present invention, the electromagnetic wave shielding resin composition includes a base resin containing a polyvinyl chloride resin and an ethylene-vinyl acetate copolymer;
A magnetic layer-covered carbon fiber formed by coating a carbon fiber with a magnetic layer made of a magnetic metal, and carbon particles,
Following formula (1):
A = Oil absorption amount of the carbon particles [ml / 100 g] × Amount of the carbon particles with respect to 100 parts by mass of the base resin / A total amount of components constituting the electromagnetic wave shielding resin composition (1)
A calculated in the above is 5-41 [ml / 100 g],
Following formula (2):
B = Amount of the magnetic layer-coated carbon fiber based on 100 parts by mass of the base resin / A (2)
B calculated in step (1) may be 1.5 to 15 [100 g / ml].

[3] In the cable with a shield layer according to one aspect of the present invention, the conductive cloth may include a PET woven cloth and a metal layer formed on both sides of the PET woven cloth.
[4] In the cable with a shield layer according to one aspect of the present invention, the metal layer may be a nickel-copper-nickel plating layer.

  According to the present invention, it is possible to suppress a decrease in electromagnetic wave shielding characteristics even if bending is repeatedly applied.

It is a figure which shows the outline | summary of the charging system containing the charging cable which concerns on this embodiment. It is a schematic sectional drawing of the charging cable which concerns on this embodiment. It is a figure which shows the structural example of the joint which connects the terminal ends of the electrically conductive cloth which concerns on this embodiment. It is a figure which shows the structural example of the charging cable used for the comparison. It is a figure which shows the electromagnetic wave shielding layer of the charging cable of this embodiment, and the charging cable used for the comparison. An example of the actual measurement result by the charging cable of this embodiment and a comparative example is shown. It is a figure which shows the example of a result of having performed 15D test with respect to the charging cable of this embodiment, and the cable of a comparative example. It is a figure which shows the example of a result of having performed 12D test with respect to the charging cable of this embodiment, and the cable of a comparative example. It is a figure which shows the example of a result of having performed 9D test with respect to the charging cable of this embodiment, and the cable of a comparative example. It is a figure which shows the example of a result of having performed the 6D test with respect to the charging cable of this embodiment, and the cable of a comparative example. It is a figure which shows the example of a result of having performed the 3D test with respect to the charging cable of this embodiment, and the cable of a comparative example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing an outline of a charging system including a charging cable according to the present embodiment. As shown in FIG. 1, the charging stand 1 includes a charging stand body 2, a charging cable 3, and a charging connector 4.

  The user H inserts a charging connector into the power supply port of the vehicle 5 to charge the vehicle 5. In this case, as shown in FIG. 1, the user H performs work by holding the charging cable 3 or the charging connector 4 with his / her hand. The distance between the charging cable 3 and the user H is L.

Next, the structure of the charging cable 3 which is a cable with a shield layer will be described.
FIG. 2 is a schematic cross-sectional view of the charging cable 3 according to the present embodiment. As shown in FIG. 2, the charging cable 3 includes two sets of conductors 11 (electric wires), two sets of insulators 12 (electric wires), a plurality of signal wires 13 (electric wires), an interposition 14, a first shield layer 15, Two shield layers 16 and a sheath 17 are provided. The charging cable 3 includes at least two conductors 11, a plurality of signal lines 13, a first shield layer 15, and a second shield layer 16 in a sheath 17.

  The conductor 11 is, for example, a copper wire, and for example, seven conductive wires are twisted. Electric power is supplied to the conductor 11 from the charging stand body 2 (FIG. 1). The insulator 12 is formed so as to cover the conductor 11 concentrically. The material of the insulator 12 is, for example, insulating paper, a nonwoven fabric, a foamed insulator, a highly foamed insulator, or the like.

  The plurality of signal lines 13 include, for example, a copper wire and an insulator that covers the copper wire concentrically. The plurality of signal lines 13 may be covered on the outer periphery of the insulator with an interposition such as jute. The number of the plurality of signal lines 13 is, for example, 8, and is arranged with two sets of conductors 11 interposed therebetween as shown in FIG. When the charging cable 3 is a cable that conforms to the CHAdeMO (registered trademark) standard, the number of signal lines 13 is nine, with two sets of conductors 11 sandwiched between two on one side and seven on the other side. Is done. The signal line 13 is used for transmitting and receiving information between the charging stand main body and the vehicle 5.

  The first shield layer 15 is formed on the outer periphery of the insulator 12 that covers the conductor 11 and the signal lines 13. The material of the first shield layer 15 is, for example, an electromagnetic wave shielding resin composition (hereinafter simply referred to as a conductive resin) containing carbon fibers having a nickel plating layer formed on the surface thereof.

  Between the insulator 12 covering the conductor 11, the plurality of signal lines 13, and the first shield layer 15, the interposition 14 is filled. The material of the interposition 14 is, for example, cotton yarn, jute, synthetic fiber or the like.

  The second shield layer 16 is provided between the first shield layer 15 and the sheath 17. The second shield layer 16 is, for example, a conductive cloth, and is wound around the outer periphery of the first shield layer 15 with ½ wrap or ３ wrap. Note that the winding of the conductive cloth around the first shield layer 15 is not limited to one sheet winding, and may be a plurality of windings (two windings, three windings,...). The first shield layer 15 and the second shield layer 16 are in contact with each other, and electrical connection is established between the conductive resin of the first shield layer 15 and the conductive cloth of the second shield layer 16. Has been. Yes. As shown in FIG. 2, the interposition 14, the first shield layer 15, the second shield layer 16, and the sheath 17 are laminated in this order from the inside of the charging cable 3.

  The sheath 17 (cover) is formed on the outer periphery of the second shield layer 16. The material of the sheath 17 is, for example, polyvinyl chloride, polyethylene, Teflon (registered trademark), or the like.

<Conductive resin>
Next, an example of the conductive resin used for the first shield layer 15 will be described.
In the present embodiment, the following conductive resin layer was used for the first shield layer 15 to measure the transfer impedance with respect to the number of bendings described later.
The first shield layer 15 is provided on the outer periphery of the interposition 14, and is formed, for example, by extrusion with a thickness of about 3 mm on a pressing tape (not shown). In addition to the materials described above, the conductive resin material may be an electromagnetic wave shielding resin composition as described in JP-A-2015-199819, for example.

  In addition, as described in JP-A-2015-199819, the electromagnetic wave shielding resin composition is composed of, for example, a base resin containing a polyvinyl chloride resin and an ethylene-vinyl acetate copolymer, and a magnetic layer made of a magnetic metal. An electromagnetic wave shielding resin composition comprising a carbon layer-coated magnetic layer-coated carbon fiber and carbon particles, the following formula (1)

A = Oil absorption amount of carbon particles [ml / 100 g] × Amount of carbon particles with respect to 100 parts by mass of the base resin / A total amount of components constituting the electromagnetic wave shielding resin composition (1)

A calculated in the above is 5 to 41 [ml / 100 g], and the following formula (2)

B = blending amount of carbon fiber coated with magnetic layer with respect to 100 parts by mass of base resin / A (2)

B calculated in the above is 1.5 to 15 [100 g / ml].
Moreover, you may make it the content rate of the polyvinyl chloride resin in a total of 100 mass% of a polyvinyl chloride resin and an ethylene-vinyl acetate copolymer be 5-40 mass%.
Moreover, you may make it the content rate of the vinyl acetate unit in an ethylene-vinyl acetate copolymer be 20 mass% or more.
The magnetic metal constituting the magnetic layer may be nickel.

<Conductive cloth>
Next, an example of the conductive cloth used in the second shield layer 16 will be described.
In this embodiment, the following conductive cloth was used for the 2nd shield layer 16, and the transmission impedance with respect to the frequency | count of bending mentioned later was measured.
・ Tape dimensions: 60 mm width × about 120 μm thickness ・ Conductive cloth structure: 100 μm thick PET (polyethylene terephthalate) base fabric (also called PET woven fabric) on both sides, about 10 μm thick Ni, Cu and Ni plating In addition, the conductive adhesive tape was used for the joint which connects the terminals of the conductive cloth.

Here, a configuration example of the joint that connects the ends of the conductive cloth used in the second shield layer 16 will be described.
In the present embodiment, when extending the conductive cloth (second shield layer 16) in the longitudinal direction, the conductive cloth (second shield layer 16) for relay-connecting the ends of the two conductive cloths as shown in FIG. Use to extend.
FIG. 3 is a diagram illustrating a configuration example of a joint that connects the ends of the conductive cloth according to the present embodiment. FIG. 3 shows an example in which the first conductive cloth (second shield layer 16 </ b> A) and the second conductive cloth (second shield layer 16 </ b> B) are connected using the conductive adhesive tape 18. Each of the first conductive cloth (second shield layer 16A) and the second conductive cloth (second shield layer 16B) is sandwiched between two conductive metal plating layers 16a and two conductive metal plating layers 16a. A base fabric layer 16b is provided. The conductive adhesive tape 18 includes two conductive metal plating layers 18a, a base fabric layer 18b sandwiched between the two conductive metal plating layers 18a, and a conductive layer provided on one conductive metal plating layer 18a. The adhesive layer 18c is provided.

Each of the base fabric layer 16b and the base fabric layer 18b has a thickness of about 100 μm.
The conductive adhesive layer 18c is, for example, an acrylic adhesive containing metal fine powder.
The conductive adhesive tape 18 has a length L of about 100 mm and a width of about 50 mm. The length L1 of the conductive adhesive tape 18 bonded to the first conductive cloth (second shield layer 16A) is about 50 mm, and is bonded to the second conductive cloth (second shield layer 16B). The length L2 of the conductive adhesive tape 18 is about 50 mm.

Here, the problem of the comparative example in the electromagnetic wave shielding layer 915 will be described.
I. Metal tape The material is, for example, copper or aluminum. The metal tape is vulnerable to repeated bending, and the metal tape cracks at an early stage, and there is a problem that the sheath breaks based on the influence. And metal tape. There is a problem that the electromagnetic wave shielding performance is significantly deteriorated when a crack occurs in the tape.
II. The metal braiding material is, for example, copper or tin-plated copper. The metal braid needs to increase the density of the braid in order to obtain high electromagnetic wave shielding performance, so that there is a problem that the cost becomes high, and there may be a problem in terms of manufacturing.

III. Metal laminate tape The material is, for example, copper-PET, copper-PET-copper. If the metal laminate tape is extremely bent or used repeatedly with bending like a cabtyre cable, there is a problem that cracks occur like the metal tape.
IV. The metal wire wire shield material is, for example, copper or tin-plated copper. The metal wire shield has a problem that high electromagnetic shielding performance cannot be obtained.

V. Conductive cloth (first comparison cable to third comparison cable in FIG. 5)
The material is, for example, a woven fabric made of an organic material, or a knitted fabric subjected to metal plating to impart conductivity. When the conductive cloth is used with repeated bending, there is a problem in that the conductive cloth is peeled off or cracks are generated in the conductive cloth itself to deteriorate the electromagnetic shielding properties.

  Hereinafter, although it demonstrates more concretely, giving an actual measurement example, the charging cable of the Example shown to the following actual measurement example is an example, and is not limited to this Example.

<Measurement example>
Below, the example of the result of having measured the change of the transmission impedance when performing various bending tests with respect to the charging cable 3 of this embodiment is demonstrated.
In actual measurement, a comparative charging cable shown in FIG. 4 and FIG. 5 was prototyped and compared with the charging cable 3 of the present embodiment. FIG. 4 is a diagram illustrating a structure example of a charging cable used for comparison. FIG. 5 is a view showing the charging cable of this embodiment and the electromagnetic wave shielding layer of the charging cable used for comparison.

As shown in FIG. 5, the cable 900 used for comparison includes two sets of conductors 911, two sets of insulators 912, a plurality of signal lines 913, interpositions 914, an electromagnetic wave shielding layer 915, and a sheath 916.
The conductor 911 corresponds to the conductor 11. The insulator 912 corresponds to the insulator 12. The plurality of signal lines 913 correspond to the signal line 13. The interposition 914 corresponds to the interposition 14.
The electromagnetic wave shielding layer 915 is formed between the interposition 914 and the sheath 916.

  As shown in FIG. 5, the first comparative cable was wound with two conductive cloths having a width of 50 mm as the electromagnetic wave shielding layer 915. In the second comparative cable, two 60 mm wide conductive cloths were wound as the electromagnetic wave shielding layer 915. In the third comparative cable, three 60 mm wide conductive cloths were wound as the electromagnetic wave shielding layer 915. In the fourth comparison cable, the conductive resin of this embodiment was formed as the electromagnetic wave shielding layer 915. In addition, the conductive resin of embodiment is a conductive resin containing the carbon fiber which formed the nickel plating layer in the surface, for example.

In addition, as the charging cable 3 of the present embodiment, two types were prototyped and actually measured.
In the first charging cable, the first shield layer 15 is the conductive resin of the present embodiment, the second shield layer 16 is the conductive cloth of the present embodiment, and the conductive cloth is ½ wrapped on the outer periphery of the conductive resin. I rolled it up. In the second charging cable, the first shield layer 15 is the conductive resin of the present embodiment, the second shield layer 16 is the conductive cloth of the present embodiment, and the conductive cloth is wrapped 1/3 on the outer periphery of the conductive resin. I rolled it up.
That is, the charging cable 3 of the present embodiment includes two shield layers between the interposition 14 and the sheath 17, and further has a second shield layer 16 made of conductive cloth on the outer periphery of the first shield layer 15 made of conductive resin. Is provided.

In FIG. 6, an example of the measurement result by the charging cable of this embodiment and a comparative example is shown.
The cable used in the comparative example is the second comparative cable shown in FIG. 5, and is a cable obtained by winding a conductive cloth having a width of 60 mm as the electromagnetic wave shielding layer 915 in a ½ wrap and two wraps. The charging cable of the present embodiment is the second charging cable shown in FIG. 5, wherein the first shield layer 15 is a conductive resin having a thickness of 3 mm, and the second shield layer 16 is a conductive cloth having a width of 60 mm. / 3 wrap and 1 wound cable.

  In the repeated bending test method shown in FIG. 6, the test was conducted according to the triaxial method of IEC1196-1 (1995). Hereinafter, a repeated bending test with a diameter D of 15 mm is referred to as a 15D test, a repeated bending test with a diameter D of 12 mm is referred to as a 12D test, and a repeated bending test with a diameter D of 15 mm is referred to as a 15D test.

  The result of the 15D test will be described. The transfer impedance when the number of reciprocal bendings was 0 was 619 [mΩ / m] for the second comparison cable, and 450 [mΩ / m] for the second charging cable of the embodiment. The transfer impedance when the number of reciprocal bendings is 1000 is 960 (× 1.55) [mΩ / m] for the second comparison cable, and 762 (× 1.69) [mΩ / m for the second charging cable of the embodiment. m]. The transfer impedance of 2000 reciprocal bendings is 1310 (× 2.12) [mΩ / m] for the second comparison cable, and 982 (× 2.18) [mΩ / m for the second charging cable of the embodiment. m].

  The result of the 12D test will be described. The transfer impedance when the number of reciprocal bendings was 0 was 661 [mΩ / m] for the second comparison cable, and 479 [mΩ / m] for the second charging cable of the embodiment. The transfer impedance when the number of reciprocating bendings is 1000 is 1237 (× 1.87) [mΩ / m] for the second comparison cable, and 1049 (× 2.19) [mΩ / m for the second charging cable of the embodiment. m]. The transfer impedance of 2000 reciprocal bendings is 1949 (× 2.95) [mΩ / m] for the second comparison cable, and 1198 (× 2.50) [mΩ / m] for the second charging cable of the embodiment. m].

  The result of the 9D test will be described. The transfer impedance when the number of reciprocal bendings was 0 was 659 [mΩ / m] for the second comparison cable, and 423 [mΩ / m] for the second charging cable of the embodiment. The transfer impedance of 1000 reciprocations is 2117 (× 3.21) [mΩ / m] for the second comparison cable, and 979 (× 2.31) [mΩ / m for the second charging cable of the embodiment. m]. The transfer impedance of 2000 reciprocal bendings is 3767 (× 5.71) [mΩ / m] for the second comparison cable, and 1514 (× 1.55) [mΩ / m] for the second charging cable of the embodiment. m].

As shown in FIG. 6, the second charging cable of the embodiment has a lower initial transmission impedance and a smaller increase in transmission impedance when the number of bendings is different than the cable of the comparative example. In particular, in the 9D test with a small diameter, the difference in how the transfer impedance increases with an increase in the number of bendings in the cable between the comparative example and the embodiment is significant.
As described above, the charging cable of the embodiment has a small increase in transmission impedance after the repeated bending test with respect to the cable of the comparative example, that is, a decrease in electromagnetic wave shielding performance is small.

Next, the results of the 15D test, 12D test, 9D test, 6D test, and 3D test, respectively, are shown in FIGS. FIG. 7 is a diagram illustrating a result example of a 15D test performed on the charging cable of the present embodiment and the cable of the comparative example. FIG. 8 is a diagram illustrating a result example of a 12D test performed on the charging cable of the present embodiment and the cable of the comparative example. FIG. 9 is a diagram illustrating a result example of a 9D test performed on the charging cable of the present embodiment and the cable of the comparative example. FIG. 10 is a diagram illustrating a result example of a 6D test performed on the charging cable of this embodiment and the cable of the comparative example. FIG. 11 is a diagram illustrating a result example of a 3D test performed on the charging cable of the present embodiment and the cable of the comparative example.
7 to 11, the horizontal axis represents the number of bendings (times), and the vertical axis represents the transfer impedance (mΩ / m).

In FIG. 7, reference numeral g11 is a test result of the first comparison cable, reference numeral g12 is a test result of the second comparison cable, and reference numeral g13 is a test result of the third comparison cable.
8 to 11, reference numerals g21, g31, g41, and g51 are test results of the fourth comparison cable. Symbols g22, g32, g42, and g52 are test results of the first charging cable of the embodiment. Symbols g23, g33, and g43 are test results of the second charging cable of the embodiment. Reference symbols g24, g34, g44, and g54 are test results of the first comparison cable. Symbols g25, g35, g45, and g55 are test results of the second comparison cable. Reference numerals g26, g36, g46, and g56 are test results of the third comparison cable.

First, the results of the 15D test will be described. In FIG. 7, reference numeral g11 is a test result of the first comparison cable, reference numeral g12 is a test result of the second comparison cable, and reference numeral g13 is a test result of the third comparison cable.
As shown in FIG. 7, the transfer impedance of the first comparison cable is 778 [mΩ / m] when the number of reciprocal bending is 0, and 955 [mΩ / m] when the number of reciprocating bending is 1000. It was 1263 [mΩ / m] when the number of reciprocal bendings was 2000. The transfer impedance of the third comparison cable is 343 [mΩ / m] when the number of reciprocal bending is 0, 500 [mΩ / m] when the number of reciprocating bending is 1000, and the number of reciprocating bending is 2000. 634 [mΩ / m] at the time of rotation. Although not shown in FIG. 7, as shown in FIG. 6, the transfer impedance of the second charging cable of the embodiment is 450 [mΩ / m] when the number of reciprocal bendings is 0, It was 762 [mΩ / m] when the number of reciprocal folds was 1000, and 982 [mΩ / m] when the number of reciprocal folds was 2000.

Next, the result of the 12D test will be described.
As shown in FIG. 8, as a result of the 12D test, in the fourth comparison cable (one-layer shield made of only conductive resin), the initial transfer impedance is twice or more that of the other cables. Furthermore, in the fourth comparison cable, the increase in the transfer impedance increases with an increase in the number of bendings, which is approximately doubled at 1000 times and approximately tripled at 2000 times. In addition, in the first comparison cable with a single-layer shield made of only 50 mm wide conductive cloth, the increase in the number of bends increases the transfer impedance, which is approximately doubled at 1000 times and tripled at 2000 times. ing.

The transfer impedance of the first charging cable of the embodiment is 306 [mΩ / m] when the number of reciprocal bendings is 0, and is 1023 [mΩ / m] when the number of reciprocating bendings is 1000, and the number of reciprocal bendings Was 1690 [mΩ / m] at 2000 times.
In addition, the transfer impedance of the second charging cable of the embodiment is 478 [mΩ / m] when the number of reciprocal bendings is 0, and is 1049 [mΩ / m] when the number of reciprocating bendings is 1000. When the number of bendings was 2000, it was 1198 [mΩ / m].

  In the 12D test, the increase in the initial transfer impedance and the transfer impedance after the repeated bending test was the smallest in the third comparison cable, the second being the second charging cable of the embodiment, and the third being the embodiment. The first charging cable was the fourth, and the fourth was the second comparison cable.

Next, the result of the 9D test will be described.
As shown in FIG. 9, as a result of the 9D test, the fourth comparison cable has little difference from the 12D test. On the other hand, in the first comparative cable, the increase in transfer impedance accompanying the increase in the number of bendings was larger than that in the 12D test, and the number of bendings was about 1800, which was higher than the transfer impedance of the fourth comparison cable. Further, even in the second comparison cable, the transfer impedance when the number of bendings was 2000 was about 4 times. As described above, even in the second comparison cable in which the result of the 12D test was relatively good, in the 9D test, the increase in the transfer impedance increased with the increase in the number of bendings.

The transfer impedance of the first charging cable of the embodiment is 328 [mΩ / m] when the number of reciprocal bendings is 0, and 1183 [mΩ / m] when the number of reciprocating bendings is 1000. Was 1743 [mΩ / m] at 2000 times.
In addition, the transfer impedance of the second charging cable of the embodiment is 423 [mΩ / m] when the number of reciprocal bendings is 0, and is 979 [mΩ / m] when the number of reciprocating bendings is 1000. When the number of bendings was 2000, it was 1514 [mΩ / m].

  In the 9D test, the increase in the initial transfer impedance and the transfer impedance after the repeated bending test was the smallest in the third comparison cable, the second was the second charging cable of the embodiment, and the third was performed. The first charging cable of the form.

Next, the result of the 6D test will be described.
As shown in FIG. 10, as a result of the 6D test, the fourth comparison cable has a small difference from the 12D test and the 9D test. On the other hand, in the first comparative cable, the increase in the transfer impedance accompanying the increase in the number of bendings was larger than that in the 12D and 9D tests, and the transfer impedance when the number of bendings was about 1100 was 8000 (mΩ / m) or more. The second comparison cable had a bending frequency of about 800 times and was larger than the transfer impedance of the fourth comparison cable, and the transmission impedance of the bending frequency of about 1800 was 8000 (mΩ / m) or more.

The transfer impedance of the first charging cable of the embodiment is 280 [mΩ / m] when the number of reciprocal bendings is 0, and 1093 [mΩ / m] when the number of reciprocal bendings is 1000. Was 1817 [mΩ / m] at 2000 times.
The transfer impedance of the second charging cable of the embodiment is 407 [mΩ / m] when the number of reciprocal bendings is 0, and is 1064 [mΩ / m] when the number of reciprocating bendings is 1000. It was 1677 [mΩ / m] when the number of bendings was 2000.

  In the 6D test, the initial transfer impedance and the increase in the transfer impedance after the repeated bending test were the smallest in the second charging cable of the embodiment, and the second was the first charging cable of the embodiment. The third was the third comparison cable.

Next, the result of the 3D test will be described.
As shown in FIG. 11, as a result of the 3D test, the increase in the transfer impedance accompanying the increase in the number of bendings of the fourth comparison cable is larger than that of the 12D to 6D test as in the first comparison cable and the second comparison cable.

  The transfer impedance of the first charging cable of the embodiment is 760 [mΩ / m] when the number of reciprocal bendings is 0, and is 2043 [mΩ / m] when the number of reciprocal bendings is 1000, and the number of reciprocal bendings Was 20000 [mΩ / m] at 2000 times.

  In the 3D test, the increase in the initial transfer impedance and the transfer impedance after the repeated bending test was the smallest in the first charging cable of the embodiment, and the second was the third comparison cable.

As described above, the reason why the first comparison cable and the second comparison cable made of only the conductive cloth deteriorate rapidly as the bending diameter decreases is that the nickel or copper plated on the base cloth is bent and the base cloth is bent. This seems to be due to peeling from the cloth. At this time, the plated copper or nickel is considered to be powdered and peeled off.
The reason for this assumption is that, as shown in FIGS. 8 to 11, the conductive resin shield layer also has a higher transfer impedance according to the number of bendings. However, even in the first charging cable and the second charging cable of the embodiment, it seems that cracks are generated in the conductive resin of the first shield layer 15, but the transfer impedance is increased as in the case of only the conductive resin. Absent. As described above, in the first charging cable and the second charging cable, the cause of the small increase in the transmission impedance with respect to the increase in the number of bendings is that the plating of the second shield layer 16 is peeled off in a powdery state according to the bending. It seems that it is because it is in the crack of conductive resin.

As described above, in the present embodiment, in the charging cable 3, the first shield layer 15 made of a conductive resin and the second shield layer made of a conductive cloth are provided so as to overlap each other between the interposition 14 and the sheath 17. In the present embodiment, the first shield layer 15 is provided on the outer periphery of the interposition 14, and the second shield layer 16 is provided on the outer periphery of the first shield layer 15.
With such a configuration, according to the present embodiment, as in the actual measurement results shown in FIG. 6 and FIG. 8 to FIG. As a result, according to the present embodiment, it is possible to prevent the electromagnetic wave shielding performance from being deteriorated even when used in an environment where bending is repeated.
In this embodiment, a conductive resin and a conductive cloth are used for the shield layer. The conductive cloth is formed of, for example, copper, nickel, or a metal layer obtained by laminating these on a PET woven cloth, and therefore has excellent extensibility and flexibility than the metal tape and conductive tape of the comparative example. Further, when the bent cable is repeatedly bent, the metal layer laminated on the PET woven fabric is peeled off between the conductive resin and the conductive cloth to generate fine powder. The generation of the fine metal powder maintains the electrical connection between the conductive resin and the conductive cloth even if the cable is bent and deformed. Accordingly, by providing the second shield layer 16 with the conductive cloth, it is possible to suppress a decrease in electromagnetic wave shielding performance even if bending is repeatedly applied.

  Furthermore, in this embodiment, the following effects are also acquired by providing the conductive cloth on the conductive resin. It is technically difficult to form a conductive resin having a magnetic wave shielding performance, and a conductive resin having a rough surface and a rough surface may be formed. Even when such a conductive resin is provided on the first shield layer 15, according to the present embodiment, the surface of the conductive resin is covered with the conductive cloth, so that the unevenness is made uniform and smooth and the appearance is smooth. The effect of forming a simple sheath 17 is also obtained.

A conductive resin having a rough surface may cause cracks in the conductive resin due to repeated bending. Even when cracks occur in this way, according to the present embodiment, by covering the conductive resin with the conductive cloth, better electromagnetic wave shielding performance can be maintained as described above.
Thereby, according to this embodiment, the electromagnetic wave which leaks outside from the charging cable 3 can be reduced, and the influence of the electromagnetic wave from the outside can also be reduced. Thus, since the electromagnetic waves leaking from the charging cable 3 can be reduced, even when used in the vicinity of the human body of the user H as shown in FIG. 1, the influence of the electromagnetic waves on the human body is prevented. be able to.

As mentioned above, although this invention has been demonstrated based on suitable embodiment, this invention is not limited to the above-mentioned embodiment, A various change is possible in the range which does not deviate from the summary of this invention.
For example, in the above-described embodiment, the charging cable 3 has been described as an example of the cable with the shield layer, but the present invention is not limited thereto. As in this embodiment, a two-layer shield layer of a conductive resin and a conductive cloth can be applied to a cable that is used in an environment where bending is repeatedly generated and electromagnetic wave shielding performance is required. For example, the cable with the shield layer includes at least one of the conductor 11, the insulator 12, or the intervening 14, the first shield layer 15, the second shield layer 16, the sheath 17, or the signal line 13, the first shield. The layer 15, the second shield layer 16, and the sheath 17 may be used.

DESCRIPTION OF SYMBOLS 1 ... Charging stand, 2 ... Charging stand main body, 3 ... Charging cable, 4 ... Charging connector, 11 ... Conductor, 12 ... Insulator, 13 ... Signal line, 14 ... Interposition, 15 ... 1st shield layer, 16 ... 1st 2 shield layers, 17 ... sheath

Claims (4)

A first shield layer and a second shield layer in contact with each other between at least one electric wire and a sheath covering the entire electric wire;
The first shield layer is an electromagnetic wave shielding resin composition, is provided between the electric wire and the second shield layer so as to cover the electric wire,
The second shield layer is a conductive cloth and is provided between the first shield layer and the sheath so as to cover the first shield layer.
Cable with shield layer. The electromagnetic wave shielding resin composition is:
A base resin comprising a polyvinyl chloride resin and an ethylene-vinyl acetate copolymer;
A magnetic layer-coated carbon fiber obtained by coating a carbon fiber with a magnetic layer made of a magnetic metal;
Carbon particles, and
Following formula (1):
A = Oil absorption amount of the carbon particles [ml / 100 g] × Amount of the carbon particles with respect to 100 parts by mass of the base resin / A total amount of components constituting the electromagnetic wave shielding resin composition (1)
A calculated in the above is 5-41 [ml / 100 g],
Following formula (2):
B = Amount of the magnetic layer-coated carbon fiber based on 100 parts by mass of the base resin / A (2)
The cable with a shield layer according to claim 1, wherein B calculated in step 1 is 1.5 to 15 [100 g / ml]. The conductive cloth is
The cable with a shield layer according to claim 1 or 2, comprising a PET woven fabric and a metal layer formed on both sides of the PET woven fabric.   The cable with a shield layer according to claim 3, wherein the metal layer is a nickel-copper-nickel plating layer.

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