JP2011009097A - Twisting-resistant cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a twisting-resistant cable for improving twisting resistance of a cable without enlarging an outer diameter of the cable, whereby, for improving lifetime of the cable through restraint of disconnection of the cable.SOLUTION: The twisting-resistant cable includes a flexible conductor 1 structured of twisting a plurality of conductors 9 around the same 9 structuring a center layer in an all-layer same direction with the use of the conductor 9 structured by twisting a plurality of strands, or a twisting all of the plurality of conductors 9 in the same direction with the conductor 9 structuring the center layer, and a shielding layer 5 structuring by mixed weave braiding a plurality of metal strands and non-metal strands at an upper part of the flexible conductor 1.

Description

  The present invention relates to a twist-resistant cable that is suitable for wiring and use in a facility having a twisting section such as a wind power generation facility or a swing crane.

  Cables that are wired and used in facilities that have twisted parts such as wind power generators and swivel cranes are twisted together with tension and repeated bending stress as external forces during use, so that they have a predetermined tensile strength and bending resistance. And twisting resistance are required.

  As a cable related to this, as seen in, for example, Patent Document 1, a shielding layer formed on the circumference of a cable core is woven and woven with a twisted wire and a cotton yarn formed by twisting a plurality of metal strands. There is a moving cable constructed by the above.

  According to this moving cable, by using a plurality of metal strands constituting the shielding layer as a stranded wire as described above, it is compared with the case of using a collective wire obtained by bundling a plurality of metal strands so far. And it has the effect that it can relieve | moderate that the said stress is added to a specific metal strand, and can suppress the disconnection of a cable.

JP-A-10-326525

  However, according to the conventional moving cable described in Patent Document 1, while having the above effect, the thickness of the shielding layer is increased by using a plurality of metal strands constituting the shielding layer as stranded wires. Since the outer diameter of the wiring becomes large, there is a problem that the wiring space must be widened. In addition, according to this moving cable, measures against twisting of the cable are insufficient. That is, Patent Document 1 does not mention anything about the conductor configuration of the cable core, but when adopting a flexible conductor that is advantageous for twisting the cable, the flexible conductor is Generally, a stranded wire formed by twisting a plurality of layers of conductors around the conductors constituting the layers is employed. In this case, for example, when the plurality of conductors constituting the first layer around the conductor constituting the central layer are twisted in the left direction (relative to the central layer), the flexible conductor is the second layer thereon. A plurality of conductors constituting each layer of the first layer and the second layer are alternately twisted in the opposite direction so that the plurality of conductors constituting the two are twisted in the opposite right direction. The third and subsequent layers are similarly twisted in the opposite direction. With this conductor configuration, when the cable is twisted in the right direction due to an external force in use, the plurality of conductors constituting the first layer operate in the “direction in which the twist is loosened” to constitute the second layer. A plurality of conductors operate in the “stretching direction”. Further, when the cable is twisted leftward, it operates in the opposite direction. When this operation is repeated along with the twisting of the cable, the plurality of conductors constituting the first layer and the second layer twisted in the opposite directions interfere with each other and rub against each other strongly. There is a possibility that a plurality of conductors constituting the first layer of the first layer are disconnected early. And this may cause the cable to break.

  Therefore, an object of the present invention is to improve the twist resistance of the cable without increasing the outer diameter of the cable, thereby suppressing the breakage of the cable and improving the cable life. It is to provide a reversible cable.

  In order to achieve the above object, the invention of claim 1 uses a conductor formed by twisting a plurality of strands and twists the plurality of conductors around the conductor constituting the center layer in the same direction in all layers. Or a flexible conductor formed by twisting all of the plurality of conductors together in the same direction together with the conductor constituting the center layer, and a plurality of metal strands and non-metals above the flexible conductor Provided is a twist-resistant cable characterized by comprising a shielding layer constituted by interweaving and braiding strands.

  According to this twist-resistant cable, by adopting the above configuration, in particular, using a conductor formed by twisting a plurality of strands, a plurality of the conductors are arranged around the conductor constituting the center layer. When the cable is twisted by twisting all layers in the same direction or by adopting a flexible conductor composed by twisting all of the conductors together in the same direction together with the conductor constituting the center layer In the conventional technology, a plurality of conductors twisted in such a manner operate in either the “direction in which the twist is loosened” or the “direction in which the twist is narrowed” depending on the twisting direction of the cable. As described above, since it does not operate in both the “direction in which the twist is loosened” and the “direction in which the twist is narrowed”, it is mitigated that these multiple conductors interfere and rub against each other strongly. It is possible to suppress the breakage of the body, it is possible to improve the 耐捻 times of the cable without increasing the outer diameter of the cable structurally. And it can suppress the disconnection of a cable by this and can improve the lifetime of a cable.

  Also, by adopting a shielding layer constructed by interweaving and braiding a plurality of metal strands and non-metallic strands, the metal of the metal strand constituting the shielding layer is compared with the case of braiding only metal strands. Disconnection due to rubbing between the strands can be suppressed. This complements the effect of improving the twisting resistance of the cable.

  The invention of claim 2 provides the twist-resistant cable according to claim 1, wherein the stranding direction of the strands is the same direction as the twisting direction of the conductor.

  According to this twist-resistant cable, in addition to the above effects, by adopting the above configuration, that is, by adopting a configuration in which the twisting direction of the strands is the same direction as the twisting direction of the conductor. In short, the above-described effects can be improved more reliably by twisting all of the strands constituting the conductor in the same direction from twisting of the conductors to twisting of the conductor.

  The invention according to claim 3 is characterized in that a launch angle at the time of braiding of the plurality of metal strands constituting the shielding layer is 60 ° or more. I will provide a.

  In the above, the reason that the launch angle at the time of braiding a plurality of metal strands is 60 ° or more is that when the launch angle is less than 60 °, the plurality of metal strands are sufficiently rich in mobility. This is because it cannot be braided. As this launch angle is increased, a plurality of metal strands can be braided in a state of high mobility, and the cable twist resistance can be improved by suppressing disconnection of the plurality of metal strands. However, since the amount of braiding increases and the cost increases, it is desirable to adjust appropriately in consideration of the twisting angle of the cable and the expected effect.

  According to this twist-resistant cable, in addition to the above effects, by adopting the above configuration, that is, the configuration in which the launch angle when braiding a plurality of metal strands constituting the shielding layer is 60 ° or more. By adopting it, instead of using a plurality of metal strands constituting the shielding layer as a stranded wire as in the prior art, a plurality of metal strands can be braided with a launch angle in a state of high mobility. Therefore, it is possible to suppress the disconnection of the plurality of metal strands, so that the twisting resistance of the cable can be improved without increasing the thickness of the shielding layer as in the prior art, and thus without increasing the outer diameter of the cable. Can be improved. And it can suppress the disconnection of a cable by this and can improve the lifetime of a cable. It is also possible to reduce the diameter of the cable.

  According to the twist resistant cable of the present invention, the twist resistance of the cable can be improved without increasing the outer diameter of the cable, thereby suppressing the disconnection of the cable and improving the life of the cable. be able to.

1 is a perspective view showing a schematic structure of a twist-resistant cable according to an embodiment of the present invention. It is explanatory drawing which shows schematic structure of the flexible conductor which comprises a twist resistant cable regarding this invention. It is a perspective view which shows schematic structure of the cable for a test for verifying the effect of this invention. It is explanatory drawing which shows the repeated twist test method of a twist resistant cable regarding this invention. It is explanatory drawing which shows schematic structure of the shielding layer which comprises a twist-resistant cable regarding this invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS.
As described above, FIG. 1 is a perspective view showing a schematic structure of a twist-resistant cable according to an embodiment of the present invention. In FIG. 1, 1 is a flexible conductor, 2 is an internal electric field relaxation layer, 3 is an insulating layer, 4 is an external electric field relaxation layer, 5 is a shielding layer, 6 is a holding tape winding layer, 7 is a sheath, and 8 is a resistance. A twisting cable is shown respectively.

  Here, as shown in FIG. 2, the flexible conductor 1 is composed of a conductor 9 formed by twisting a plurality of strands (not shown), and using one conductor 9 constituting a central layer. Twist the six conductors 9 around in the same direction (in the direction of the thick arrow in the figure) (concentric twist), or all the six conductors 9 together with one conductor 9 constituting the center layer It is formed by twisting (aggregate twist) in the direction of the thin arrow (→ in the figure). In short, this conductor structure is a so-called compound twist structure in which a plurality of conductors 9 formed by twisting a plurality of strands are further twisted in the same direction. Moreover, the twisting direction of the unillustrated strands and the twisting direction of the conductor 9 are configured as the same direction.

  In the case of concentric twisting, the single conductor 9 constituting the central layer is twisted in the same direction together with the six conductors 9 twisted around the conductor 9 without actively twisting it. Can be handled in the same way. In this concentric twisting, a plurality of twisted layers formed by twisting a plurality of conductors 9 are provided around one conductor 9 constituting the center layer, and all layers are twisted in the same direction. It may be configured.

  According to this twist-resistant cable 8, as already described, the conductor 9 formed by twisting a plurality of strands (not shown) is used to surround the single conductor 9 constituting the center layer. By adopting the flexible conductor 1 formed by twisting the six conductors 9 in the same direction or by twisting all the six conductors in the same direction together with the conductors 9 constituting the center layer, When the wire 8 is twisted, the plurality of conductors 9 twisted in such a manner operate in the “direction in which the twist is loosened” or the direction in which the twist is tightened, depending on the twisting direction of the cable 8. However, as described in the prior art, both the “direction in which the twist is loosened” and the “direction in which the twist is narrowed” are not performed, so that the multiple conductors 9 interfere with each other and strongly rub against each other. As a result, these leads It is possible to suppress the breakage of 9, it is possible to improve the 耐捻 times of the cable without increasing the outer diameter of the cable structurally. And it can suppress the disconnection of a cable by this and can improve the lifetime of a cable.

  On the other hand, the shielding layer 5 formed around the external electric field relaxation layer 4 above the flexible conductor 1 includes a plurality of metal wires 10 and non-metal wires 11 as shown in FIG. It is composed by weaving braiding. That is, the shielding layer 5 is configured by braiding a plurality of metal wires 10 and non-metal wires 11 alternately in opposite directions around the external electric field relaxation layer 4 using a braiding machine. Further, the launch angle θ during braiding of the plurality of metal strands 10 constituting the shielding layer 5 is set to 60 ° or more. Here, as the metal wire 10, for example, a tin-plated annealed copper wire is used, and as the non-metal wire 11, for example, a cotton thread is used.

  According to this twist-resistant cable 8, as already described, by setting the launch angle at the time of braiding of the plurality of metal wires 10 constituting the shielding layer 5 to 60 ° or more, the shielding layer can be formed as in the prior art. Instead of using a plurality of constituent metal strands as stranded wires, a plurality of metal strands 10 can be braided with a launch angle in a state of high mobility, thereby suppressing disconnection of the plurality of metal strands 10. Therefore, the twisting resistance of the cable can be improved without increasing the thickness of the shielding layer as in the prior art, and thus without increasing the outer diameter of the cable. And it can suppress the disconnection of a cable by this and can improve the lifetime of a cable. It is also possible to reduce the diameter of the cable.

  In the present invention, the three twist-resistant cables 8 can be twisted to be used as a twist-resistant cable having a triplex structure, thereby preventing an electrical imbalance as a cable. be able to.

Example 1
As shown in FIG. 3, a test cable 12 simulating the twist-resistant cable 8 of FIG. 1 was produced. The test cable 12 is configured by sequentially providing a separator 14, an insulating layer 15, and a sheath 16 on a flexible conductor 13. As the flexible conductor 13, by using a conductor formed by twisting a plurality of tin-plated annealed copper wires, by twisting the plurality of conductors around the conductor constituting the center layer in the same direction in all layers. Configured. Further, the twisting direction of the plurality of tin-plated annealed copper wires constituting the conductor and the twisting direction of the plurality of the conductors were all the same direction.

  Next, using this test cable 12, as shown in FIG. 4, a cable repeated twist test method was performed. That is, one end of the test cable 12 having a length of 3 m is fixed by the fixing bracket 17 provided above, the test cable 12 is suspended, and the weight 18 is suspended from the other end of the test cable 12. A vertical load of 10 kg was applied to 12. In this state, the test cable 12 was repeatedly twisted in the direction of the arrow in the range of ± 120 ° / m.

  As a result, no breakage occurred in the tin-plated annealed copper wire in the 50,000-times repeated twist test, and finally a break was found in the tin-plated annealed copper wire in the central portion of the flexible conductor 13 in the 100,000-times repeated twist test. It came to be able to. At this time, the disconnection rate was 2.7% of the entire tin-plated annealed copper wire.

(Example 2)
In the twist-resistant cable 8 of FIG. 1, the launch angle θ at the time of braiding of the plurality of metal strands 10 constituting the shielding layer 5 is set to 60 °, and a tin-plated annealed copper wire is used as the metal strand 10. A twisting cable was prepared, and three twisting cables were twisted to produce a twisting cable having a triplex structure. In addition, as the non-metal strand 11 which comprises the shielding layer 5 with the metal strand 10, cotton yarn was used.

  Using this twist-resistant cable, the same repeated twist test method as described above was performed. However, a weight suspended from the other end of the twist-resistant cable applies a vertical load of 120 kg to the twist-resistant cable, and the twist-resistant cable is repeatedly twisted 10,000 times within a range of ± 45 ° / m. did.

  As a result, the braiding disorder and kink did not occur in the tin-plated annealed copper wire constituting the shielding layer, and no breakage was observed in the three twist-resistant cables (three-core) constituting the triplex structure. .

(Comparative Example 1)
About the test cable 12 used in Example 1, the test cable similar to Example 1 was produced except that a plurality of conductors of each layer constituting the flexible conductor were twisted in opposite directions.

  Using this test cable, the twist test method was repeated in the same manner as in Example 1.

  As a result, almost all of the tin-plated annealed copper wire in the inner layer portion of the flexible conductor was disconnected in the repeated twisting test of 50,000 times. At this time, the disconnection rate was 30% of the entire tin-plated annealed copper wire.

(Comparative Example 2)
The twist resistance of the triplex structure used in Example 2 was the same as in Example 2 except that the launch angle θ during braiding of the tin-plated annealed copper wire constituting the shielding layer was 30 °. A cable was produced.

  Using this twist resistant cable, the twist test method was repeated in the same manner as in Example 2. However, by changing the weight hung on the other end of the twist-resistant cable, a vertical load of 90 kg is applied to the twist-resistant cable, and the twist-resistant cable is 5000 times within a range of ± 45 ° / m. Twisted repeatedly.

  As a result, braiding disorder and kinking occur in the tin-plated annealed copper wire constituting the shielding layer for all three twist-resistant cables constituting the triplex structure (3-wire core), and partial disconnection is also observed. It was.

  From the above examples and comparative examples, according to the twist-resistant cable according to the present invention, by forming a flexible conductor by twisting a plurality of conductors around the conductor constituting the central layer in the same direction in all layers. In addition, it is understood that the twist resistance of the cable can be improved without increasing the outer diameter of the cable by forming a shielding layer by interweaving and braiding a plurality of metal wires and non-metal wires. . Further, by setting the launch angle θ at the time of braiding the plurality of metal strands constituting the shielding layer to be 60 ° or more, the plurality of metal strands can be braided in a state of high mobility. It can be seen that the twist resistance of the cable can be improved without increasing the outer diameter of the cable.

  It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the invention.

DESCRIPTION OF SYMBOLS 1, 13 Flexible conductor 2 Internal electric field relaxation layer 3, 15 Insulation layer 4 External electric field relaxation layer 5 Shielding layer 6 Holding tape winding layer 7, 16 Sheath 8 Torsion-resistant cable 9 Conductor 10 Metal element 11 Non-metal element Wire 12 Test cable 14 Separator 17 Fixing bracket 18 Weight

Claims (3)

  Using a conductor formed by twisting a plurality of strands, a plurality of the conductors are twisted in the same direction around the conductor constituting the center layer, or a plurality together with the conductor constituting the center layer. A flexible conductor formed by twisting all the conductors in the same direction, and a shielding layer formed by interweaving a plurality of metal strands and non-metal strands above the flexible conductor. A torsion-resistant cable characterized by comprising.   The twist-resistant cable according to claim 1, wherein a twisting direction of the strands is the same as a twisting direction of the conductor.   The twist-resistant cable according to claim 1 or 2, wherein a launch angle at the time of braiding of the plurality of metal strands constituting the shielding layer is 60 ° or more.

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