JP2016115668A - Shield cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield cable of providing a predetermined characteristic impedance.SOLUTION: There is provided a shield cable 1 comprising two signal lines in which a signal conductor 2 is covered by an insulator 3 and a shield conductor 6 in which a tape 5 with metallic foil is spirally wound on the periphery of a bundle of the two signal lines 4. The insulator has a section deformable by external force. 80% or more to 95% or less of the signal line remains uncollapsed when the signal line is subjected to a 1-kg load for 30 minutes. Preferably, upper and lower metallic foils at an overlapped part of winding of the tape with metallic foil, contact electrically with each other by folding one edge part of the tape with metallic foil in a manner where the metallic foil is arranged outside or inside.SELECTED DRAWING: Figure 1A

Description

  The present invention relates to a shielded cable, and more specifically, a signal line in which two signal conductors are covered with an insulator, and a shield conductor formed by spirally winding a tape with a metal foil around the signal line. It relates to the shielded cable provided.

  A shielded cable in which a plurality of, for example, two signal lines are paired is used to transmit a digital signal by a differential transmission method. In this differential transmission method, for example, a signal whose phase is inverted by 180 degrees is simultaneously input and transmitted to a pair of signal lines, and the signal output can be doubled by performing differential synthesis on the receiving side. Further, the noise signal received on the transmission path from transmission to reception is equally applied to the pair of signal lines. For this reason, when it outputs as a differential signal on the receiving side, it is canceled and noise can be removed.

  These pair of signal lines are shielded with a metal foil, but the strength is not sufficient with only the metal foil, and therefore, for example, a tape with a metal foil obtained by attaching a metal foil to a resin tape is used. On the other hand, when the metal foil tape is spirally stacked, the overlapping portion of the tape is not in electrical contact, so that a sack-out phenomenon (a rapid increase in signal attenuation) may occur in the high frequency range. Therefore, for example, Patent Document 1 discloses a technique in which the overlapping metal foils are in electrical contact with each other vertically.

JP 2011-222262 A

  In the shielded cable, the characteristic impedance is set so that a good signal transmission characteristic can be obtained in the operating frequency range. This characteristic impedance changes due to deformation of the cross section of the signal line. In the above Patent Document 1, nothing is disclosed about the relationship between the change in characteristic impedance and the deformation of the signal line.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a shielded cable capable of obtaining a predetermined characteristic impedance.

  A shielded cable according to an aspect of the present invention is a shielded conductor in which two signal lines in which a signal conductor is covered with an insulator and a tape with metal foil are collectively wound around the two signal lines. The insulator is configured such that its cross section can be deformed by an external force. When the load of 1 kg is applied to the signal line for 30 minutes, the remaining crush rate of the signal line is 80 % To 95%.

  According to the above, a predetermined characteristic impedance can be obtained.

It is a figure explaining the outline of the shielded cable which concerns on 1 aspect of this invention. It is a figure explaining the shield conductor of FIG. 1A. It is a figure which shows the verification result (pitch more than 4.0 mm) of the signal attenuation | damping of the shielded cable of FIG. 1A. It is a figure which shows the verification result (pitch 4.0mm) of the signal attenuation | damping of the shielded cable of FIG. 1A. It is a figure which shows the verification result (pitch 2.5mm) of the signal attenuation | damping of the shielded cable of FIG. 1A. It is a figure which shows the verification result (pitch 2.0mm) of the signal attenuation | damping of the shielded cable of FIG. 1A. It is a figure explaining the structural example of the signal wire | line of FIG. 1A. It is a figure explaining the form of the signal wire | line of FIG. 1A. It is a figure explaining the relationship between the change of the characteristic impedance of the signal wire | line of FIG. 1A, and a deformation | transformation of a signal wire | line. FIG. 6 is a diagram illustrating a signal line according to a second embodiment. It is a figure explaining the relationship between the change of the characteristic impedance of the signal wire | line of Example 2, and a deformation | transformation of a signal wire | line. FIG. 6 is a diagram illustrating a signal line according to a third embodiment. It is a figure explaining the relationship between the change of the characteristic impedance of the signal wire | line of Example 3, and a deformation | transformation of a signal wire | line. It is a figure explaining the outline of the other example of the shielded cable which concerns on 1 aspect of this invention. It is a figure explaining the shield conductor of FIG. 7A.

[Description of Embodiment of the Present Invention]
First, the contents of the embodiment of the present invention will be listed and described.
A shielded cable according to an aspect of the present invention includes: (1) two signal lines in which a signal conductor is covered with an insulator, and a tape with metal foil wound around the two signal lines in a spiral. A shield cable comprising a shield conductor, wherein the insulator is configured such that a cross section thereof can be deformed by an external force, and the signal line is not crushed when a load of 1 kg is applied to the signal line for 30 minutes. The rate is 80% or more and 95% or less. Since the degree of deformation of the signal line cross section (the remaining crush rate of the signal line) is 80% or more and 95% or less, the characteristic impedance of the cable does not deviate from the design value. As a result, it is possible to prevent the signal waveform from being corrupted in the used frequency range. The signal line crush remaining rate is, for example, a value obtained by dividing the diameter of the deformed signal line in the case where an external force is applied to the insulator by the diameter of the signal line before deformation. is there.
(2) When one edge of the tape with metal foil is folded back with the metal foil on the outside or inside, the upper and lower metal foils are in electrical contact with each other at the overlapping portion of the tape with metal foil. ing. Since the shield current flows in a straight line parallel to the signal line, the suck-out phenomenon can be reduced.

(3) The insulator is a single layer and is a foam layer. In this case, the signal line can be easily manufactured.
(4) The insulator is formed of two layers, the outer layer is a solid layer, and the inner layer is a foamed layer. Since the outermost layer having the highest hardness is mainly crushed, it becomes difficult to be crushed as compared with a case where a material that is easily deformed is crushed, and a predetermined crushing residual rate can be easily obtained.
(5) The insulator is formed of three layers, the outermost layer and the innermost layer are solid layers, and the intermediate layer is a foamed layer. Since the outermost layer having the highest hardness is mainly crushed, it becomes difficult to be crushed as compared with a case where a material that is easily deformed is crushed, and a predetermined crushing residual rate can be easily obtained.

(6) The winding pitch of the tape with metal foil is 2.0 mm or greater and 4.0 mm or less. Or (7) The winding pitch of the said tape with metal foil is 3.5 mm or more and 4.0 mm or less. In this case, the sack-out phenomenon can be eliminated while preventing a decrease in cable productivity. More preferably, (8) The winding pitch of the tape with metal foil is 2.0 mm or more and 2.5 mm or less.
(9) A presser winding member wound spirally around the metal foil tape is provided. The tape with metal foil can be protected. Further, when the metal foil of the folded portion is arranged inside the winding, the metal foil is arranged outside the whole winding, so that the metal foil can be insulated by the presser winding member.
(10) An outer cover is provided around the metal foil tape. It is possible to provide a shielded cable that can insulate the tape with metal foil, prevent contamination from the outside, and have water resistance.

[Details of the embodiment of the present invention]
Embodiments of the present invention will be described in detail with reference to the drawings. 1A and 1B are diagrams illustrating an outline of a shielded cable according to one embodiment of the present invention. The shielded cable 1 shown in FIG. 1A is, for example, a twinax cable, and a tape 5 with metal foil is spirally wound around two parallel signal wires 4 that are parallel to each other so that two signal wires are in parallel contact with each other. It has been.

  The signal line 4 is formed by covering the signal conductor 2 with an insulator 3. The signal conductor 2 is formed of, for example, a good electric conductor such as copper or aluminum, a single wire of a tin-plated or silver-plated electric good conductor, or a twisted wire in which a good electric conductor is twisted, and is equivalent to AWG 20 to 36 (the outer diameter of the conductor is 0). .115 mm to 0.910 mm) is used. The insulator 3 has a small dielectric constant, and for example, polyethylene (PE), ethylene vinyl acetate copolymer (EVA), fluororesin, or the like is used. A foamed insulating resin may also be used. The outer diameter of the signal line 4 is 3.0 mm to 0.15 mm. For example, when the signal conductor 2 of the AWG 26 is used, the outer diameter is about 1.25 mm.

The two signal lines 4 are covered with a shield conductor 6. Specifically, the shield conductor 6 is formed by winding a tape 5 with metal foil in a spiral shape, and shields the two signal lines 4 together.
As shown in FIG. 1B, the metal foil-attached tape 5 is formed by attaching a metal foil 5a such as copper or aluminum to a resin tape 5b such as polyethylene terephthalate (PET). The thickness of the metal foil 5a is 3 to 30 μm (preferably 6 to 10 μm for copper, for example 8 μm), and the thickness of the resin tape 5b is 3 to 50 μm (preferably 3 to 10 μm for PET, for example 4 μm). Yes, the thickness of the tape 5 with metal foil is 6 μm to 80 μm.

  The shield conductor 6 can also be covered with a jacket 7. In this case, the outer jacket 7 is provided by extruding a thermoplastic resin such as polyethylene, polyvinyl chloride, or fluororesin. A resin tape may be wound around. By providing the jacket 7, it is possible to insulate the tape 5 with metal foil, prevent contamination from the outside, and provide a cable having water resistance.

Here, the tape 5 with metal foil is overlapped and wound, for example, at 8 ° to 70 ° with respect to the axis orthogonal to the cable longitudinal direction, and the lower and upper metal foils 5a are electrically connected to each other in the overlapping portion of the winding. Are in contact.
Specifically, as shown in FIG. 1B, a folded portion 6a is formed at one edge portion of the tape 5 with metal foil, and the metal foil 5a of the folded portion 6a is disposed outside the winding. For this reason, the tape 5 with metal foil is wound around the outer periphery of the signal line 4 so that the metal foil 5a other than the folded portion 6a is disposed inside. At this time, the metal foil 5a provided on the edge portion that does not have the folded portion 6a of the next turn is overlapped with the metal foil 5a of the folded portion 6a, and the upper and lower metal foils 5a are in electrical contact with each other. As a result, the shield current flows in a straight line parallel to the signal line 4, so that the suck-out phenomenon can be reduced.

The width L of the folded portion 6a is preferably about 1/4 to 1/2 of the winding width W of the tape 5 with metal foil. For example, in the tape 5 with a metal foil having a width of 7 mm, the width L of the folded portion 6a is folded back to 2 mm, and the winding width W of the tape 5 is set to 5 mm.
Further, if the width L of the folded portion 6a is small, the conduction of the metal foil 5a at the overlapping portion may not be sufficient, but if the width L of the folded portion 6a is too large, the tape 5 with metal foil is wasted, Winding may be disturbed. For this reason, it is preferable that the width of the overlapping portion of the winding is substantially the same as or slightly longer than the width L of the folded portion 6a. For example, when the width L of the folded portion 6a is 2 mm, the winding overlap portion is wound with a width of 2 mm to 2.3 mm.

In addition, it is also possible to arrange | position the metal foil of a folding | turning part inside a winding. In this case, the tape with the metal foil is wound around the outer periphery of the signal line so that the metal foil other than the folded portion is disposed outside.
Further, the tape 5 with metal foil may be spirally wound around its periphery by a presser winding member (not shown). The presser winding member is, for example, a resin tape such as PET, and can protect the tape 5 with metal foil. In addition, as will be described later with reference to FIG. 7, when the metal foil 5a of the folded portion 6a is disposed inside the winding, the tape 5 with the metal foil is signaled so that the metal foil 5a other than the folded portion 6a is disposed outside. Since the wire 4 is wound around the outer periphery, the metal foil 5a can be insulated by the presser winding member.

2A to 2D are diagrams illustrating verification results of signal attenuation of the shielded cable of FIG. 1A.
When the winding pitch P of the metal foil tape shown in FIG. 1B exceeds 4.0 mm, as shown in FIG. 2A, a suck-out phenomenon occurred at 25 GHz to 30 GHz, and the signal level was lowered. On the other hand, when the winding pitch P of the metal foil-attached tape was 4.0 mm, the attenuation of the sac-out decreased as shown in FIG. 2B. For applications where the frequency of the signal to be transmitted is lower than 25 GHz, the shielded cable of the present invention in which the winding pitch of the metal foil tape is 4.0 mm can also be used. When the winding pitch P of the tape with metal foil was 2.5 mm and when the winding pitch P was 2.0 mm, no suck-out phenomenon occurred in the frequency range of 40 GHz or less (FIGS. 2C and 2D). If the winding pitch is reduced, the cable becomes difficult to bend, and the amount of the tape with the metal foil to be wound increases and the productivity of the cable decreases. Since these disadvantages cannot be ignored if the pitch is smaller than 2.0 mm, the winding pitch P of the tape with metal foil is preferably 2.0 mm or more and 4.0 mm or less, and 2.0 mm or more and 2.5 mm or less. More preferably.

FIG. 3 is a diagram illustrating an example of the structure of the signal line in FIG. 1A.
The signal line 4 described above can be deformed by an external force. Specifically, as shown in FIG. 3, the signal line 4 having a circular cross section is sandwiched between, for example, two metal plates 10 and pressed from a direction perpendicular to the longitudinal direction of the signal line 4 (for example, the vertical direction in FIG. 2). Yes. For this pressurization, for example, a weight of 1 kg is continuously applied for 30 minutes.

As a result, the insulator 3 is deformed, and a flat portion is formed on the outer periphery of the signal line 4 at the contact position with the metal plate 10. This flat portion is not restored after the pressurization is stopped, and the insulator 3 remains deformed.
The shielded cable 1 described with reference to FIG. 1A is manufactured by arranging two signal lines 4 having a circular cross section having such a crushed property and then collectively shielding with the metal foil tape 5 as described above. ing.

4A and 4B are diagrams illustrating the form of the signal lines in FIG. 1A. The insulator 3 shown in FIG. 4A is formed of only one main layer 3b in which low density polyethylene (LDPE) and high density polyethylene (HDPE) are mixed, and the main layer 3b has a predetermined degree of foaming and bubbles. A foamed insulating resin having a diameter. The insulator is cross-linked.
The signal line 4 of the cable 1 was taken out, the diameter before and after the pressurization was measured, the signal line crush remaining rate was obtained, and the relationship between the change in characteristic impedance and the deformation of the signal line was derived (FIG. 4B).

The signal line of the sample 1 is obtained by coating a signal conductor of AWG 30 (φ0.254 mm) with an insulator having a main layer 3b thickness of 0.243 mm. The main layer 3b has a foaming degree (volume ratio of foamed portions in the foamed layer) of 45.5 to 50.3%, and a bubble diameter of 20 to 70 μm.
In the sample 1, the diameter of the signal line before deformation is 0.74 mm, whereas the diameter of the signal line after deformation (for example, a flat portion formed at a contact position with the metal plate 10 shown in FIG. 3). The distance between them was 0.65 mm, and the remaining crushing rate was 88%. The characteristic impedance of the cable using Sample 1 was within 5% of the design value (100Ω), and good evaluation was obtained.

The signal line of sample 2 is obtained by coating a signal conductor of AWG28 (φ0.352 mm) with an insulator having a main layer 3b thickness of 0.324 mm. The main layer 3b has a foaming degree of 48.0 to 56.2% and a bubble diameter of 20 to 70 μm.
In sample 2, the diameter of the signal line before deformation was 1 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) was 0.8 mm, and the remaining crushing rate was 80%. . The characteristic impedance of the cable using Sample 2 was also good.

The signal line of the sample 3 is obtained by coating a signal conductor of AWG26 (φ0.445 mm) with an insulator having a thickness of 0.403 mm of the main layer 3b. The main layer 3b has a foaming degree of 49.0 to 58.8% and a bubble diameter of 20 to 70 μm.
In sample 3, the diameter of the signal line before deformation is about 1.25 mm, whereas the diameter of the signal line after deformation (the distance between the flat portions) is 0.9 mm, and the remaining crush rate is 72%. Met. The characteristic impedance of the cable using the sample 3 was shifted by 5% or more with respect to the design value (100Ω), and good evaluation could not be obtained.

The signal line of the sample 4 is obtained by coating a signal conductor of AWG24 (φ0.562 mm) with an insulator having a thickness of 0.514 mm of the main layer 3b. The main layer 3b has a foaming degree of 53.7 to 56.6% and a bubble diameter of 20 to 70 μm.
In sample 4, the diameter of the signal line before deformation is 1.59 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) is 1.17 mm, and the remaining crush rate is 74%. there were. The characteristic impedance of the cable using the sample 4 was shifted by 5% or more with respect to the design value (100Ω), and good evaluation could not be obtained.

  In this way, when the signal line is crushed, if the remaining crush rate is less than 80%, the characteristic impedance of the cable deviates from the design value due to the deformation of the cross section of the signal line, and the predetermined characteristic impedance cannot be obtained. . And this causes the insertion loss to deteriorate. Further, when the crush remaining rate is less than 80%, the appearance of the signal line is poor.

5A and 5B are diagrams for explaining the signal lines of the second embodiment.
The insulator 3 shown in FIG. 5A is formed of two layers: an outer layer 3a made of HDPE, and a main layer 3b in which LDPE and HDPE are mixed. The outer layer 3a is a solid layer, and the main layer 3b is a foamed insulating resin. Since the outer layer is a solid layer, the signal line has good wear resistance and is easy to attach a shield layer. Similar to Example 1, the relationship between the change in characteristic impedance and the deformation of the signal line was derived (FIG. 5B).

The signal line of the sample 5 is obtained by coating a signal conductor of AWG30 (φ0.254 mm) with an insulator having a main layer 3b thickness of 0.163 mm and an outer layer thickness of 0.08 mm. The main layer 3b has a foaming degree of 45.5 to 50.3% and a bubble diameter of 20 to 70 μm.
In sample 5, the diameter of the signal line before deformation is 0.74 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) is 0.69 mm, and the remaining crush rate is 93%. there were. The characteristic impedance of the cable using the sample 5 was within 5% of the design value (100Ω), and good evaluation was obtained.

The signal line of the sample 6 is obtained by coating a signal conductor of AWG28 (φ0.352 mm) with an insulator having a main layer 3b thickness of 0.244 mm and an outer layer thickness of 0.08 mm. The main layer 3b has a foaming degree of 48.0 to 56.2% and a bubble diameter of 20 to 70 μm.
In sample 6, the diameter of the signal line before deformation was 1 mm, whereas the diameter of the signal line after deformation (the distance between the flat portions) was 0.84 mm, and the remaining crushing rate was 84%. . The characteristic impedance of the cable using Sample 6 was also good.

The signal line of the sample 7 is obtained by coating a signal conductor of AWG26 (φ0.445 mm) with an insulator having a main layer 3b thickness of 0.303 mm and an outer layer thickness of 0.1 mm. The main layer 3b has a foaming degree of 49.0 to 58.8% and a bubble diameter of 20 to 70 μm.
In the sample 7, the diameter of the signal line before deformation is about 1.25 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) is 1 mm, and the remaining crush rate is 80%. It was. The characteristic impedance of the cable using the sample 7 was also good.

The signal line of the sample 8 is obtained by coating a signal conductor of AWG24 (φ0.562 mm) with an insulator having a main layer 3b thickness of 0.414 mm and an outer layer thickness of 0.1 mm. The main layer 3b has a foaming degree of 53.7 to 56.6% and a bubble diameter of 20 to 70 μm.
In sample 8, the diameter of the signal line before deformation is 1.59 mm, whereas the diameter of the signal line after deformation (the distance between the flat portions) is 1.27 mm, and the remaining crush rate is 80%. there were. The characteristic impedance of the cable using the sample 8 was also good.

6A and 6B are diagrams for explaining a signal line according to the third embodiment.
The insulator 3 shown in FIG. 6A is formed of three layers: an outer layer 3a made of HDPE, a main layer 3b obtained by mixing LDPE and HDPE, and an inner layer 3c made of LDPE. The outer layer 3a and the inner layer 3c are solid layers. The main layer 3b is a foamed insulating resin. Then, similarly to Examples 1 and 2, the relationship between the change in characteristic impedance and the deformation of the signal line was derived (FIG. 6B).

The signal line of the sample 9 is an AWG30 (φ0.254 mm) signal conductor made of an insulator having an inner layer 3c thickness of 0.02 mm, a main layer 3b thickness of 0.143 mm, and an outer layer thickness of 0.08 mm. It is coated. The main layer 3b has a foaming degree of 45.5 to 50.3% and a bubble diameter of 20 to 70 μm.
In sample 9, the diameter of the signal line before deformation is 0.74 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) is 0.7 mm, and the remaining crush rate is 95%. there were. The characteristic impedance of the cable using the sample 9 was also good.

The signal line of the sample 10 is an AWG28 (φ0.352 mm) signal conductor made of an insulator having an inner layer 3c thickness of 0.02 mm, a main layer 3b thickness of 0.224 mm, and an outer layer thickness of 0.08 mm. It is coated. The main layer 3b has a foaming degree of 48.0 to 56.2% and a bubble diameter of 20 to 70 μm.
In sample 10, the diameter of the signal line before deformation was 1 mm, whereas the diameter of the signal line after deformation (distance between the flat portions) was 0.85 mm, and the remaining crushing rate was 85%. . The characteristic impedance of the cable using the sample 10 was also good.

The signal line of the sample 11 is an AWG26 (φ0.445 mm) signal conductor made of an insulator having an inner layer 3c thickness of 0.02 mm, a main layer 3b thickness of 0.283 mm, and an outer layer thickness of 0.1 mm. It is coated. The main layer 3b has a foaming degree of 49.0 to 58.8% and a bubble diameter of 20 to 70 μm.
In the sample 11, the diameter of the signal line before deformation is about 1.25 mm, whereas the diameter of the signal line after deformation (the distance between the flat portions) is 1 mm, and the remaining crush rate is 80%. It was. The characteristic impedance of the cable using the sample 11 was also good.

The signal line of the sample 12 is an AWG24 (φ0.562 mm) signal conductor made of an insulator having an inner layer 3c thickness of 0.02 mm, a main layer 3b thickness of 0.394 mm, and an outer layer thickness of 0.1 mm. It is coated. The main layer 3b has a foaming degree of 53.7 to 56.6% and a bubble diameter of 20 to 70 μm.
In sample 12, the diameter of the signal line before deformation is 1.59 mm, whereas the diameter of the signal line after deformation (the distance between the flat portions) is 1.27 mm, and the remaining crush rate is 80%. there were. The characteristic impedance of the cable using the sample 12 was also good.

On the other hand, it was found that when the remaining crush rate exceeds 95%, the appearance failure of the signal line does not occur, but the characteristic impedance of the cable deviates from the design value and the predetermined characteristic impedance cannot be obtained.
In the signal line 4 shown in FIG. 4A, when the remaining crush rate exceeds 95%, the result is the same as that of the signal line 4 shown in FIG. 6A. Further, in the signal line 4 shown in FIGS. 5A and 6A, when the remaining crush rate is less than 80%, the result is the same as that of the signal line 4 shown in FIG. 4A.

Therefore, when an external force is applied, the material of the insulator, the degree of foaming, and the like may be determined so that the remaining crush rate of the signal line is 80% or more and 95% or less. Thus, since the degree of cross-sectional deformation that is difficult to deviate from the design value is derived, the characteristic impedance of the cable does not deviate from the design value. As a result, it is possible to prevent the signal waveform from being corrupted in the used frequency range.
In addition, in the two-core parallel cable in which the two signal lines are arranged in parallel and shielded, the signal level is gently lowered, and no sac-out phenomenon occurs. In addition, the characteristic impedance is 9 psec / m or less compared to a two-core parallel cable made of a signal line when the crush remaining rate is less than 80% or exceeds 95%, and the signal propagating through each core of the cable is less than 9 psec / m. The delay time difference was reduced.

7A and 7B are diagrams illustrating an outline of another example of the shielded cable according to one embodiment of the present invention.
As shown in FIG. 7A, in this shielded cable 1, the drain line 8 is placed in a recess (groove) formed in parallel with the signal line 4 and is wound around the shield line 6 together with the signal line 4. In this case, as shown in FIG. 7B, a folded portion 6a is formed at one edge portion of the tape 5 with metal foil, and the metal foil 5a of the folded portion 6a is arranged outside the winding (similar to FIG. 1B). ). For this reason, the tape 5 with metal foil is wound around the outer periphery of the signal line 4 so that the metal foil 5a other than the folded portion 6a is disposed inside. At this time, the metal foil 5a provided on the edge portion that does not have the folded portion 6a of the next turn is overlapped with the metal foil 5a of the folded portion 6a, and the upper and lower metal foils 5a are in electrical contact with each other. The metal foil 5a is also connected to the drain line 8.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the meanings described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Shield cable, 2 ... Signal conductor, 3 ... Insulator, 3a ... Outer layer, 3b ... Main layer, 3c ... Inner layer, 4 ... Signal wire, 5 ... Tape with metal foil, 5a ... Metal foil, 5b ... Resin Tape 6 Shield conductor 6a Folding portion 7 Outer jacket 8 Drain wire 10 Metal plate

Claims (10)

A shielded cable comprising two signal lines in which signal conductors are covered with an insulator, and a shield conductor formed by spirally winding a tape with metal foil around the two signal lines,
The insulator is configured such that a cross section thereof can be deformed by an external force, and a remaining crush rate of the signal line when a load of 1 kg is applied to the signal line for 30 minutes is 80% or more and 95% or less. .   When one edge of the tape with metal foil is folded with the metal foil outside or inside, the upper and lower metal foils are in electrical contact with each other at the overlapping portion of the winding with the metal foil, The shielded cable according to claim 1.   The shielded cable according to claim 1 or 2, wherein the insulator is formed of one layer and is a foam layer.   The shielded cable according to claim 1 or 2, wherein the insulator is formed of two layers, the outer layer is a solid layer, and the inner layer is a foamed layer.   The shielded cable according to claim 1 or 2, wherein the insulator is formed of three layers, the outermost layer and the innermost layer are solid layers, and the intermediate layer thereof is a foamed layer.   The shielded cable according to any one of claims 1 to 5, wherein a winding pitch of the tape with the metal foil is 2.0 mm or greater and 4.0 mm or less.   The shield cable according to any one of claims 1 to 5, wherein a winding pitch of the metal foil-attached tape is 3.5 mm or greater and 4.0 mm or less.   The shielded cable according to claim 6, wherein the winding pitch of the tape with metal foil is 2.0 mm or more and 2.5 mm or less.   The shielded cable according to any one of claims 1 to 8, further comprising a presser winding member that is spirally wound around the metal foil tape. The shielded cable according to any one of claims 1 to 9, further comprising a jacket applied around the tape with the metal foil.

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