cable

Abstract

Provided is a cable that has improved bending resistance and good transmission characteristics. A cable (1) includes a cable core (5) having a linear filler (2) and a plurality of signal transmission cores (3), a shield layer (7) that covers the periphery of the cable core (5), and a sheath (8) that covers the periphery of the shield layer (7). The filler (2) is composed of a first filler (21) disposed at the center of the cable and a plurality of second fillers (22) disposed around the first filler (21) in a cross shape with the first filler (21) in a cross-sectional view perpendicular to the length direction of the cable. The cable core (5) is formed by twisting the plurality of signal transmission cores (3) and the plurality of second fillers (22) around the first filler (21) in a spiral shape in an alternating arrangement in the circumferential direction.

Description

Technical Field

[0001] This invention relates to cables. Background Technology

[0002] Communication cables used for signal transmission include, for example, LAN cables and coaxial cables. In particular, as a LAN cable, Patent Document 1 proposes a twisted-pair cable comprising: a cross-shaped interposer extending radially from the center and having four partitions; twisted-pair wires disposed between the partitions of the cross-shaped interposer; and a shielding layer and a sheath sequentially disposed around the outer periphery of the cross-shaped interposer and the twisted-pair wires.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 5457241 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] In recent years, there has been a demand in industrial robots and other applications for cables used to transmit signals across moving or oscillating parts. For these cables, good transmission characteristics and high bending resistance, such as those meeting Category 6A standards, are required.

[0008] However, when using the aforementioned twisted-pair cable with a cross-shaped insert as a cable for wiring in the movable and swaying parts, the cross-shaped insert is not easily bent and is prone to breakage when the cable is repeatedly bent, thus resulting in insufficient bending resistance. Furthermore, if the cross-shaped insert breaks, crosstalk occurs at the break point, increasing the crosstalk between the twisted pairs (pair-to-pair crosstalk). Additionally, the position of the twisted pairs becomes unstable, which can sometimes degrade transmission characteristics.

[0009] Therefore, the object of the present invention is to provide a cable that can improve bending resistance and obtain good transmission characteristics.

[0010] Methods for solving problems

[0011] To address the aforementioned issues, the present invention provides a cable comprising: a cable core having a linear interposer and a plurality of wire cores for signal transmission; a shielding layer covering the periphery of the cable core; and a sheath covering the periphery of the shielding layer. The interposer is composed of a first interposer and a plurality of second interposers. The first interposer is disposed at the center of the cable, and the plurality of second interposers are disposed around the first interposer in a cross-sectional view perpendicular to the length direction of the cable, forming a cross shape with the first interposer. The cable core is formed by spirally twisting the plurality of wire cores and the plurality of second interposers around the first interposer in an alternating circumferential arrangement.

[0012] Invention Effects

[0013] According to the present invention, a cable that can improve bending resistance and obtain good transmission characteristics can be provided. Attached Figure Description

[0014] Figure 1 This is a cross-sectional view showing a section perpendicular to the length direction of a cable according to one embodiment of the present invention.

[0015] Figure 2 This is a cross-sectional view showing a section perpendicular to the length direction of a cable according to a variation of the present invention.

[0016] Figure 3 This is a cross-sectional view showing a section perpendicular to the length direction of a cable according to a variation of the present invention.

[0017] Figure 4 This is a diagram illustrating the bending resistance test.

[0018] Symbol Explanation

[0019] 1: Cable

[0020] 2: Intermediate object

[0021] 21: The first intermediate object

[0022] 22: The second intermediary

[0023] 3: Wire core

[0024] 30: Twisted pair cable

[0025] 31: Insulated wires

[0026] 5: Cable core

[0027] 6: Compressed belt

[0028] 7: Shielding layer

[0029] 8: Sheath. Detailed Implementation

[0030] [Implementation Method]

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0032] Figure 1 This is a cross-sectional view showing the cable according to this embodiment, perpendicular to its length. Cable 1 is a signal transmission cable (so-called a LAN cable) used in industrial robots and the like for wiring across movable and swinging parts. The cable 1 according to this embodiment is a Category 6A LAN cable.

[0033] like Figure 1 As shown, the cable 1 includes: a cable core 5 having a linear interposer 2 and multiple cores 3 for signal transmission, a crimping tape 6 wound around the cable core 5, a shielding layer 7 provided in such a way as to cover the area around the crimping tape 6, and a sheath 8 covering the area around the shielding layer 7.

[0034] (Core 3)

[0035] In this embodiment, the core 3 is composed of twisted pair wires 30. The twisted pair wires 30 are used to transmit differential signals and are formed by twisting together a pair of insulated wires 31. In this embodiment, four twisted pair wires 30 are used, for a total of eight insulated wires 31. It should be noted that the number of twisted pair wires 30 (core 3) used in the cable 1 is not limited to this. Furthermore, the core 3 can also be a two-core parallel cable, etc., consisting of a pair of insulated wires 31 arranged in parallel, in addition to twisted pair wires 30.

[0036] The insulated wire 31 constituting the twisted pair 30 has a conductor 311 and an insulator 312 covering the conductor 311. To improve bending durability, the conductor 311 is preferably a stranded conductor formed by twisting together multiple bare metal wires. In this embodiment, the conductor 311 is a stranded conductor formed by twisting together multiple bare metal wires, such as tinned soft copper wire with an outer diameter of 0.08 mm.

[0037] To achieve a smaller diameter cable 1, it is preferable to make the insulation 312 as thin as possible. The thickness of the insulation 312 is preferably set to, for example, 0.10 mm to 0.30 mm. It should be noted that the outer diameter of the insulated wire 31 is preferably, for example, 0.6 mm to 1.0 mm. In this embodiment, a thin-walled insulator 312 made of extrudable fluoropolymer resin is used. Examples of fluoropolymer resins used in the insulator 312 include FEP (perfluoroethylene propylene copolymer) and PFA (perfluoroalkoxyalkane). Alternatively, an insulator made of PE (polyethylene) or PP (polypropylene) can also be used as the insulator 312. It should be noted that when the insulator 312 is made of fluoropolymer resin containing FEP or PFA, compared to when it is made of PE or PP, the friction (i.e., easy slippage) when the surface of the insulator 312 comes into contact with other components (intermediates, insulators 312 of other insulated wires 31) during repeated bending of the cable is reduced. Therefore, the cable 1 can obtain high bending resistance.

[0038] Furthermore, the insulator 312 is preferably formed into a cylindrical shape by tubular extrusion around the conductor 311. This allows the conductor 311 to move along the length of the insulated wire 31 within the insulator 312, making it less likely for the conductor 311 to break when the cable 1 is bent.

[0039] In each twisted pair 30, the twisting direction of the conductor 311 is opposite to the twisting direction of the twisted pair 30. This is because, for example, if the twisting directions of the conductor 311 and the twisted pair 30 are set to the same direction, the twisted pair 30 may be twisted along the direction in which the conductor 311 is twisted, increasing the load on the bare metal wire contained in the conductor 311, making it easier for the cable 1 to break when bent. It should be noted that the twisting direction of the conductor 311 refers to the direction in which the bare metal wire rotates from one end to the other when viewed from one end of the insulated wire 31. Similarly, the twisting direction of the twisted pair 30 refers to the direction in which the insulated wire 31 rotates from one end to the other when viewed from one end of the twisted pair 30.

[0040] To suppress crosstalk (also known as inter-pair crosstalk) between twisted pairs 30, it is preferable to set the twist pitch of each twisted pair 30 differently. For example, the twist pitch of each twisted pair 30 is preferably different within the range of 10mm to 20mm, and the difference in twist pitch between each twisted pair 30 is preferably 2mm or more. It should be noted that the twist pitch of the twisted pair 30 refers to the spacing along the length of the twisted pair 30 at any insulated wire 31 located in the same circumferential direction.

[0041] (Intermediate Item 2)

[0042] The intermediate 2 consists of one first intermediate 21 and four second intermediates 22, arranged in a cross shape in a cross section perpendicular to the cable length direction.

[0043] The first intermediary 21 is disposed at the center of the cable. The center of the cable is the part where stress is most easily concentrated when bending the cable 1. By disposing of the first intermediary 21 at the center of the cable, the load applied to each twisted pair 30 when the cable 1 is repeatedly bent can be suppressed, the breakage of the insulated wire 31 can be suppressed, and the bending resistance can be improved.

[0044] The second interposer 22 suppresses crosstalk by separating the twisted pairs 30 (cores 3) from each other in the circumferential direction, and is disposed between adjacent twisted pairs 30 in the circumferential direction. That is, in the cable 1, the twisted pairs 30 and the second interposer 22 are alternately disposed around the outer periphery of the first interposer 21 in the circumferential direction. The outer diameter of the first interposer 21 is larger than the outer diameter of the second interposer 22, preferably, for example, 1.5 to 1.7 times the outer diameter of the second interposer 22. As a result, the bending resistance of the cable 1 when the twisted pairs 30 and the second interposer 22 are alternately disposed can be further improved. In this embodiment, the outer diameter of the first interposer 21 is set to 1.66 times the outer diameter of the second interposer 22. That is, the thickness of the first interposer 21 is larger than that of the second interposer 22, and the cross-sectional area of ​​the section perpendicular to the length direction of the cable is larger than that of the second interposer 22.

[0045] The outer diameter of the second dielectric 22 is approximately the same as the outer diameter of the twisted pair 30 (core 3). More specifically, the outer diameter of the second dielectric 22 is preferably 0.8 times or more and 1.0 times or less of the outer diameter of the twisted pair 30 (core 3). By setting the outer diameter of the second dielectric 22 to 0.8 times or more of the outer diameter of the twisted pair 30, even when the cable 1 is repeatedly bent, adjacent twisted pairs 30 in the circumferential direction can be sufficiently separated, thus suppressing crosstalk. To further suppress crosstalk, the outer diameter of the second dielectric 22 is more preferably 0.9 times or more of the outer diameter of the twisted pair 30. Furthermore, if the outer diameter of the second dielectric 22 is larger than the outer diameter of the twisted pair 30, the gap around the twisted pair 30 becomes larger, making the arrangement of the twisted pair 30 unstable and potentially degrading the transmission characteristics. Therefore, the outer diameter of the second dielectric 22 is preferably 1.0 times or less of the outer diameter of the twisted pair 30. That is, by setting the outer diameter of the second interposer 22 to less than 1.0 times the outer diameter of the twisted pair 30, the configuration of the twisted pair 30 can be stabilized even when the cable 1 is repeatedly bent, the distance between the twisted pairs 30 can be easily kept fixed, and the degradation of transmission characteristics caused by the positional deviation of the twisted pair 30 can be suppressed. Here, the outer diameter of the twisted pair 30 is set to 1.28 mm, and the outer diameter of the second interposer 22 is set to 1.20 mm.

[0046] In this embodiment, four second interposers 22 are arranged at equal intervals around the first interposer 21. Therefore, in a cross-section perpendicular to the cable length direction, the first interposer 21 and the second interposers 22 are integrated and configured as a generally cross-shaped interposer. Conventionally, communication cables using an interposer with a cross-shaped cross-section perpendicular to the cable length direction are known. However, in such communication cables, the cross-shaped interposer makes the cable difficult to bend, or the cross-shaped interposer, which is difficult to bend repeatedly, prone to breakage. If the interposer breaks, crosstalk will occur at the break point, increasing the inter-pair crosstalk. In addition, the position of the twisted pair 30 will become unstable, thus degrading the transmission characteristics.

[0047] In contrast, in this embodiment, since a cross-shaped interposer 2 is formed by the first interposer 21 disposed at the center of the cable and a plurality of second interposers 22 disposed separately from the first interposer 21 around it, when the cable 1 is bent, the first interposer 21 and the second interposers 22 move relative to each other along the length of the cable, thus dispersing the stress during bending. As a result, even if the cable 1 is repeatedly bent, the first and second interposers 21 and 22 are not easily broken, which improves the bending resistance and suppresses the positional deviation of the twisted pair 30 and the increase of crosstalk between pairs, thus maintaining good transmission characteristics.

[0048] Furthermore, in this embodiment, the plurality of second interposers 22 are configured to be able to contact and separate from the first interposer 21 when the cable core 5 is bent. This further suppresses the breakage of the second interposers 22 when the cable is bent, and further improves bending resistance.

[0049] The first interposer 21 and the second interposer 22 are preferably made of materials with smooth surfaces and low wear resistance. Furthermore, to suppress degradation of transmission characteristics, the first interposer 21 and the second interposer 22 are preferably made of materials with the lowest possible dielectric constant. Examples of common materials for the first interposer 21 and the second interposer 22 that satisfy these characteristics include PE (polyethylene), fluoropolymers, and XF-coated wires with XF (modified fluoropolymer) coated on the resin surface.

[0050] Here, in order to suppress manufacturing costs, the first interposer 21 and the second interposer 22 are made of the same material, but this is not a limitation, and the first interposer 21 and the second interposer 22 may also be made of different materials. In this case, the first interposer 21, which is located at the center of the cable, bears a larger load when bent, so the tensile strength of the first interposer 21 is preferably set to be greater than or equal to the tensile strength of the second interposer 22.

[0051] Furthermore, in this embodiment, the cross-sectional shapes of the first interposer 21 and the second interposer 22 are set to circular shapes (circular shapes when no load is applied). However, this is not a limitation; the cross-sectional shapes of the first interposer 21 and the second interposer 22 may also be elliptical or polygonal. However, from the viewpoints of easily achieving overall cable balance by aligning with the shape of the twisted pair 30, suppressing the contact area between the twisted pair 30, the interposers 21 and 22, and facilitating movement along the cable length direction during bending, it is arguably more preferable to set the cross-sectional shapes of the first interposer 21 and the second interposer 22 to circular shapes.

[0052] (Cable core 5)

[0053] The cable core 5 is constructed by spirally twisting four twisted pairs 30 and four second interposers 22 around the first interposer 21. The twisted pairs 30 and second interposers 22 are arranged alternately in a circumferential direction. The twisting direction of the cable core 5 is opposite to the twisting direction of the twisted pairs 30. That is, the twisting direction of the cable core 5 is the same as the twisting direction of the conductor 311. It should be noted that the twisting direction of the cable core 5 refers to the direction in which the twisted pairs 30 and the second interposers 22 rotate from one end of the cable core 5 towards the other end when viewed from one end of the cable core 5.

[0054] In this embodiment, since the outer diameter of the second interposer 22 is smaller than the outer diameter of the twisted pair 30, the twisted pair 30 is in direct contact with the outer surface of the first interposer 21 and the inner surface of the compression tape 6. The second interposer 22 is arranged to fill the gap between adjacent twisted pairs 30 and the inner surface of the compression tape 6 in the circumferential direction, so that adjacent twisted pairs 30 in the circumferential direction are in direct contact with the compression tape 6, but not with the first interposer 21.

[0055] (Compression belt 6)

[0056] The compression tape 6 is spirally wound around the cable core 5. The compression tape 6 serves to prevent the cable core 5 from unwinding and to isolate the cable core 5 from the shielding layer 7. The compression tape 6 is spirally wound around the cable core 5 with a portion of its width overlapping. In order to prevent the compression tape 6 from damaging the shielding layer 7 when the cable 1 is repeatedly bent, it is preferable to use a compression tape with the lowest possible rigidity and low restoring force (elasticity) that allows it to return to a straight shape. For example, a compression tape made of paper tape or non-woven fabric tape is preferred.

[0057] (Shielding layer 7)

[0058] The shielding layer 7 is composed of a braided shielding material made of multiple bare metal wires, and is arranged to cover the area around the compression tape 6. In this embodiment, a two-layer shielding layer 7 is used, consisting of a first shielding layer 71 arranged to cover the area around the compression tape 6 and a second shielding layer 72 arranged to cover the area around the first shielding layer 71, but the shielding layer 7 can also be a single layer.

[0059] To achieve a smaller cable diameter and improved flexibility, the bare metal wires used in the first and second shielding layers 71 and 72 are preferably bare metal wires with an outer diameter of less than 0.10 mm. In this embodiment, bare metal wires made of soft copper wire with an outer diameter of 0.08 mm are used. It should be noted that the first and second shielding layers 71 and 72 can also be cross-wound shields, which are made by spirally winding multiple metal braids. In addition, the bare metal wires constituting the first and second shielding layers 71 and 72 can be bare wires made of copper, aluminum, or alloys thereof, or bare wires with a metal layer made of metal foil or metal plating on the outer surface of the fiber filaments.

[0060] (Sheath 8)

[0061] The sheath 8 is provided to cover the periphery of the shielding layer 7 (second shielding layer 72). In this embodiment, a sheath made of polyvinyl chloride resin is used as the sheath 8. However, the material of the sheath 8 is not limited to this; for example, it can be a resin composition with at least one resin as the main component (base), such as polyurethane resin, fluoropolymer, or fluororubber. It should be noted that the thickness of the sheath 8 is 0.6 mm or more and 1.0 mm or less, and the outer diameter of the cable 1 is 6.0 mm or more and 9.0 mm or less. In this embodiment, the thickness of the sheath 8 is set to 0.8 mm, and the outer diameter of the cable 1 is set to 7.2 mm.

[0062] (Evaluation of transmission characteristics)

[0063] Trial production Figure 1 For cable 1, the crosstalk (far-end crosstalk) and attenuation between each twisted pair 30 were measured. Crosstalk and attenuation were measured using a network analyzer at a frequency of 1.0MHz to 500.0MHz under conditions of 8m cable length, 20℃. The crosstalk measurement results and Category 6A standard values ​​are summarized in Table 1. The attenuation measurement results and Category 6A standard values ​​are summarized in Table 2. It should be noted that in Tables 1 and 2, the four twisted pairs 30 are represented by A through D. For example, the column in Table 1 with A in the first row and B in the second row represents the crosstalk between twisted pair A and twisted pair B.

[0064] [Table 1]

[0065]

[0066] [Table 2]

[0067]

[0068] As shown in Tables 1 and 2, it is confirmed that the cable 1 involved in this embodiment meets the Class 6A standard values ​​for inter-pair crosstalk and attenuation in the frequency band of 1.0MHz to 500.0MHz, and has good transmission characteristics.

[0069] (Evaluation of bending resistance)

[0070] Make 3 Figure 1 Cable 1 was used, and the bending resistance of the three manufactured cables 1 was evaluated by performing 90-degree bend tests on both sides. Figure 4 As shown, the 90-degree left and right bending test is conducted as follows: A hammer with a load of 2N (0.2kgf) is suspended from the lower end of the cable 1 used as the sample. With bending clamps 100 of a bending shape installed on the left and right sides of the cable 1, the cable 1 is bent by applying a bending angle of ±90° in the left and right directions along the bending clamps 100. The bending radius R is set to approximately twice the outer diameter of the cable 1 (approximately 7.2mm). The bending speed is set to 30 times / minute, and the number of bends is counted as one reciprocating motion in the left and right directions. Then, the cable 1 is repeatedly bent, and the continuity of the conductor 311 is checked between the two ends of the cable 1 each time. When the resistance value increases by 20% compared to the resistance value before the test (initial resistance value), it is considered that a breakage has occurred, and the number of bends at this point is recorded as the bending life.

[0071] For the three cables 1 manufactured, a 90-degree bending test was conducted under the harsh condition that the bending radius R was approximately twice the outer diameter of the cable 1. The results showed that the increase in resistance value was only 0.1% to 3.4% when the number of bending cycles reached 1 million. That is, in the cable 1 according to this embodiment, even when the number of bending cycles reaches 1 million, the resistance value of the conductor 311 hardly increases (the increase in resistance value is less than 5%), and the bending life is not reached.

[0072] (Modified Example)

[0073] In this embodiment, the case where the first intervening object 21 is made of a single material has been described, but it is not limited to this; the first intervening object 21 may also be made of a combination of multiple materials. For example, as Figure 2As shown in cable 1a, the first interposer 21 may also have a tension member 21a and an insulation layer 21b covering the periphery of the tension member. The tension member 21a can be, for example, a material made of twisted steel wires, high-tensile fibers, etc. By having a tension member 21a in the first interposer 21, the tension member 21a can withstand tensile forces during bending, achieving high bending resistance to suppress wire breakage even in applications such as repeated severe bending or cable laying.

[0074] In addition, such as Figure 3 As shown in the cable 1b, the first interlayer 21 can also be formed by spirally winding resin tape 21d around the insulating layer 21c with a circular cross-section. For example, PTFE is an expensive material that has good surface smoothness. By using an inexpensive resin such as PE in the insulating layer 21c and winding resin tape 21d made of a material with good smoothness such as PTFE around it, it is possible to achieve a first interlayer 21 with good surface smoothness while reducing costs, and thus achieve a low-cost cable 1b with good bending resistance.

[0075] (The role and effects of the implementation method)

[0076] As explained above, the cable 1 according to this embodiment includes: a linear first interposer 21 disposed at the center of the cable; multiple twisted pairs 30 formed by twisting a pair of insulated wires 31 together; multiple linear second interposers 22 in the same number as the twisted pairs 30; a shielding layer 7 disposed in such a way as to cover the periphery of the cable core 5, the cable core 5 being formed by spirally twisting multiple twisted pairs 30 and multiple second interposers 22 around the first interposer 21 in such a way as to alternately arrange the twisted pairs 30 and the second interposers 22 in the circumferential direction; and a sheath 8 covering the periphery of the shielding layer 7.

[0077] By using the second interposer 22 to separate adjacent twisted pairs 30 in the circumferential direction, the inter-pair distance can be increased, thus suppressing inter-pair crosstalk and achieving good transmission characteristics that meet the Category 6A standard. Furthermore, by configuring the first interposer 21 and the second interposer 22 separately, the second interposer 22 can move relative to the first interposer 21 along the cable length, making it less prone to breakage even when the cable 1 is repeatedly bent.

[0078] Furthermore, by setting the outer diameter of the second interposer 22 to be more than 0.8 times and less than 1.0 times the outer diameter of the twisted pair 30, it is possible to ensure the inter-pair distance and suppress inter-pair crosstalk, and even when the cable is bent, the position of the twisted pair 30 (the positional relationship between the twisted pairs 30) can be kept fixed, thus enabling the cable 1 to have high bending resistance that can withstand millions to tens of millions of repeated bends and good transmission characteristics that fully meet the standard values ​​of Category 6A.

[0079] (Summary of implementation methods)

[0080] Next, based on the technical concept grasped from the embodiments described above, reference numerals and the like used in the embodiments will be used for description. However, the constituent elements in the claims are not limited to the components specifically shown in the embodiments, etc., as described below.

[0081] [1] A cable (1) comprising: a cable core (5) having a linear interposer (2) and a plurality of wire cores (3) for signal transmission, a shielding layer (7) covering the periphery of the cable core (5), and a sheath (8) covering the periphery of the shielding layer (7), wherein the interposer (2) is composed of a first interposer (21) and a plurality of second interposers (22), the first interposer (21) being disposed at the center of the cable, and the plurality of second interposers (22) being disposed around the first interposer (21) in a cross-shaped manner in a cross-sectional view perpendicular to the length direction of the cable, wherein the cable core (5) is formed by spirally twisting the plurality of wire cores (3) and the plurality of second interposers (22) around the first interposer (21) in a manner that alternates along the circumferential direction.

[0082] [2] According to the cable (1) described in [1], the plurality of second mediators (22) are configured to be able to contact and separate from the first mediator (21) when the cable core (5) is bent.

[0083] [3] According to the cable (1) described in [1] or [2], the outer diameter of the first interposer (21) is larger than the outer diameter of the second interposer (22).

[0084] [4] In any one of the cables (1) according to [1] to [3], the outer diameter of the second interposer (22) is more than 0.8 times and less than 1.0 times the outer diameter of the core.

[0085] [5] In any one of the cables (1) according to [1] to [4], the tensile strength of the first interposer (21) is greater than or equal to the tensile strength of the second interposer (22).

[0086] [6] In any one of [1] to [4], the above-mentioned core (3) is composed of twisted pair (30).

[0087] The embodiments of the present invention have been described above, but the embodiments described above are not limited to the invention as defined in the claims. Furthermore, it should be noted that not all combinations of features described in the embodiments are necessary for the method used to solve the inventive problem. Additionally, the present invention can be implemented with appropriate modifications without departing from its spirit.

Claims

1. A cable comprising: A cable core having multiple cores for both linear media and signal transmission; A shielding layer covering the area surrounding the cable core; and The sheath covering the area around the shielding layer, The intervening element consists of a first intervening element and a plurality of second intervening elements. The first intervening element is disposed at the center of the cable, and the plurality of second intervening elements are disposed around the first intervening element in a cross-shaped arrangement with the first intervening element in a cross-sectional view perpendicular to the length direction of the cable. The cable core is formed by spirally twisting the plurality of wire cores and the plurality of second interposers around the first interposer in an alternating circumferential arrangement. The wire core is composed of twisted pairs. The second intermediary does not come into contact with the first intermediary. The outer diameter of the first interposer is larger than the outer diameter of the second interposer, and the outer diameter of the first interposer is 1.5 to 1.7 times the outer diameter of the second interposer.

2. The cable according to claim 1, wherein the plurality of second mediators are configured to be able to contact and separate from the first mediator when the cable core is bent.

3. The cable according to claim 1 or 2, wherein the outer diameter of the second intermediate is more than 0.8 times and less than 1.0 times the outer diameter of the conductor.

4. The cable according to claim 1 or 2, wherein the tensile strength of the first interposer is greater than or equal to the tensile strength of the second interposer.

5. The cable according to claim 1 or 2, wherein a compression tape is provided between the cable core and the shielding layer, spirally wound around the cable core. The second medium has its adjacent twisted pairs in the circumferential direction in direct contact with the compression tape.

6. The cable according to claim 1 or 2, wherein the twisted pair is composed of insulated wire having a conductor and an insulator covering the conductor, the conductor being composed of a stranded conductor formed by twisting together multiple bare metal wires, the twisting direction of the twisted pair being opposite to the twisting direction of the conductor, and the cable core being formed by spirally twisting multiple twisted pairs and multiple second interposers around the first interposer in a manner that alternates in a circumferential direction.

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