JP2018049812A - Two-core parallel cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-core parallel cable capable of reducing output quantity (Scd21) of a common mode to input signals of a differential mode in transmission of differential signals.SOLUTION: A cable has a pair of insulation wires 2 aligned in parallel in contact each other, a first resin tape 3 wound around the pair of insulation wires 2 and a shield tape 4 would around an outside of the first resin tape 3 in vertical attachment and containing a metallic layer 4a. The cable has a drain wire 5 at outside of the shield tape 4, and the drain wire 5 is arranged to electrically contact with the metallic layer 4a of the shield tape 4. It also has jacket layer 6 arranged around the shield tape 4 and the drain wire 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a two-core parallel cable.

  A two-core parallel cable including a conductive shield tape wound around a pair of insulated wires arranged in parallel and an insulation tape wound outside the shield tape is known (for example, a patent References 1 and 2).

JP 2002-319319 A US Pat. No. 7,790,981

  When transmitting differential signals in a two-core parallel cable, if the signal line (insulated wire, etc.) moves relative to the conductive shield tape, the shielding effect on the signal line becomes unstable, and the common mode for differential mode input signals Output amount (Scd21) may increase.

  An object of the present invention is to provide a two-core parallel cable capable of reducing a common mode output amount (Scd21) with respect to a differential mode input signal in transmission of a differential signal.

The two-core parallel cable according to one aspect of the present invention is
A pair of insulated wires arranged in parallel in contact with each other;
A first resin tape wound around the pair of insulated wires;
A shield tape that is wound vertically on the outside of the first resin tape and includes a metal layer;
Is provided.

  According to the above invention, in the transmission of the differential signal, the common mode output amount (Scd21) with respect to the differential mode input signal can be reduced.

It is a perspective view which shows the structure of the two-core parallel cable which concerns on 1st embodiment. It is sectional drawing orthogonal to the length direction of the two-core parallel cable of FIG. It is a perspective view which shows the other structure of the two-core parallel cable which concerns on 2nd embodiment. It is sectional drawing orthogonal to the length direction of the two-core parallel cable of FIG.

(Description of Embodiment of the Present Invention)
First, embodiments of the present invention will be listed and described.
The two-core parallel cable according to one aspect of the present invention is
(1) a pair of insulated wires arranged in parallel in contact with each other;
A first resin tape wound around the pair of insulated wires;
A shield tape that is wound vertically on the outside of the first resin tape and includes a metal layer;
Is provided.
According to the above configuration, the pair of insulated wires that are in contact with each other and arranged in parallel are wound by the first resin tape, so that the mutual position of the two insulated wires can be reliably fixed. Further, the shield tape is wound vertically on the outer side of the first resin tape, and has better electrical characteristics than the case of horizontal winding. As a result, the shielding effect on the insulated wire (signal line) by the shield tape is stabilized, and the common mode output amount (Scd21) for the differential mode input signal can be reduced.

(2) having a drain wire outside the shield tape;
The drain line is disposed so as to be electrically connected to the metal layer of the shield tape.
Since the drain wire is provided outside the shield tape, there is no drain wire inside the shield tape, and the shield tape can be closely attached to the first resin tape inside.

(3) It has a jacket layer provided around the shield tape and the drain line.
By providing the jacket layer, it is possible to insulate the shield tape, prevent contamination from the outside, and make the cable resistant to water.

(4) having a conductive tape spirally wound outside the shield tape;
The drain line is disposed outside the conductive tape so as to be electrically connected to the conductive tape and the shield tape,
The jacket layer is provided around the conductive tape and the drain line.
Since the conductive tape is wound spirally (laterally) around the outer periphery of the shield tape, the shield tape is less prone to wrinkles, and the shield effect is less likely to vary with respect to the insulated wire (signal line). Therefore, it is possible to reduce the variation while reducing the common mode output amount (Scd21) with respect to the differential mode input signal.

(5) The jacket layer is a layer formed by winding a second resin tape around the shield tape and the drain wire.
By winding the second resin tape, the shield tape and the drain wire are securely connected electrically.

(6) The winding direction in which the second resin tape is wound is opposite to the winding direction of the first resin tape.
Since the 2nd resin tape which forms a jacket layer is wound in the reverse direction to the 1st resin tape, it can make it difficult to attach a twist crease to an insulated wire.

(Details of the embodiment of the present invention)
Specific examples of the two-core parallel cable according to the embodiment of the present invention will be described below with reference to the drawings.
In addition, this invention is not limited to these illustrations, is shown by the claim, and intends that all the changes within the meaning and range equivalent to a claim are included.

(First embodiment)
As shown in FIGS. 1 and 2, the two-core parallel cable 1 of the first embodiment is wound around a pair of insulated wires 2 that are in contact with each other and arranged in parallel, and a pair of insulated wires 2. The first resin tape 3 is provided. The two-core parallel cable 1 includes a shield tape 4 wound around the first resin tape 3, a drain wire 5 disposed outside the shield tape 4, and the periphery of the shield tape 4 and the drain wire 5. The jacket layer 6 is provided.

  The insulated wire 2 includes a signal conductor 21 provided at the center and an insulator 22 that covers the periphery of the signal conductor 21. The signal conductor 21 is a single wire or a stranded wire formed of, for example, a conductor such as copper or aluminum, a conductor plated with tin, silver, or the like. The dimensions of the conductor used for the signal conductor 21 are, for example, AWG38 to AWG22 in the AWG (American Wire Gauge) standard. The insulator 22 is made of, for example, polyethylene (PE), ethylene vinyl acetate copolymer (EVA), a fluororesin, or the like. The outer diameter of the insulated wire 2 is, for example, about 0.3 mm to 3.0 mm. For example, when the signal conductor 21 of the AWG 30 is used, it is about 0.9 mm.

  The first resin tape 3 is formed of a resin tape such as polyethylene terephthalate (PET) or polyvinyl chloride (PVC). It is preferable that an adhesive is applied to one surface of the first resin tape 3. The surface to which the adhesive is applied may be the inner surface on the side in contact with the pair of insulated wires 2 or the outer surface on the non-contact side. As for the wound 1st resin tape, a double stitch is fixed with an adhesive agent, and the wound shape is maintained. The first resin tape 3 is preferably wound spirally (laterally) around the pair of insulated wires 2. The spirally wound first resin tape 3 is overlaid so that a part of the winding tape overlaps. The thickness of the first resin tape 3 is, for example, about 4 μm to 50 μm.

  The shield tape 4 is formed of a resin tape with a metal layer obtained by bonding or vapor-depositing a metal layer 4a such as copper or aluminum to a resin tape such as PET. The thickness of the shield tape 4 is, for example, about 10 μm to 50 μm, and the thickness of the metal layer 4 a is, for example, about 0.1 μm to 20 μm. In addition, you may make it use the resin tape with a metal layer by which the metal tape was stuck on both surfaces, for example, the metal tape which both surfaces consist of metal, and the resin tape for the shield tape 4. The shield tape 4 is wound around the outside of the first resin tape 3 with vertical attachment. It is preferable that the adhesive tape is attached to the part of the shield tape 4 that is vertically attached. The overlapping portion is fixed with an adhesive, and the rolled shape is maintained. The shield tape 4 is wound so that the metal layer 4a is disposed on the outside.

As shown in FIG. 2, the drain wire 5 has a shield tape 4 and a second resin tape on each lateral side surface of the insulated wire 2 in a direction orthogonal to the length direction of the two-core parallel cable 1 (lateral direction in FIG. 2). 6a is attached vertically.
The two drain wires 5 are arranged symmetrically with respect to the insulated wire 2, for example. In the example of FIG. 2, the center point 5c of each drain line 5 and the center point 21c of each signal conductor 21 are arranged on a straight line (straight line C). The drain line 5 may be only one. The drain line 5 is provided so as to be in electrical contact with the metal layer 4 a disposed outside the shield tape 4. The outer diameter of the drain wire 5 is, for example, about 0.08 mm to 0.8 mm.

  The jacket layer 6 is an insulating layer formed by winding a resin tape such as PET or PVC. The jacket layer 6 is formed of a plurality of layers, and in this example, is formed of two layers of second resin tapes 6a and 6b. The thickness of the resin tapes 6a and 6b is, for example, about 4 μm to 50 μm. The jacket layer 6 may be a single layer. The second resin tapes 6 a and 6 b are preferably wound around the shield tape 4 and the drain wire 5 in a spiral shape (lateral winding). The winding direction in which the second resin tape 6a or 6b is wound is opposite to the winding direction of the first resin tape 3 in this example. The winding directions of the second resin tapes 6a and 6b may be reversed, and one second resin tape may be wound in the same direction as the first resin tape. When the jacket layer 6 is formed in, for example, two layers, the adhesiveness between the layers can be increased by applying an adhesive to one surface of the second resin tape 6a (or 6b). A colored tape may be inserted between the layers for marking the two-core parallel cable 1. The jacket layer 6 may be formed by extruding a thermoplastic resin such as polyethylene, polyvinyl chloride, or fluororesin.

  According to the two-core parallel cable 1 configured as described above, since the pair of insulated wires 2 arranged in parallel in contact with each other are wound by the first resin tape 3, the two insulated wires 2 are mutually connected. The position can be fixed securely. When the first resin tape 3 is spirally wound around the insulated wire 2, the tape is less likely to be opened when the cable is bent than in the case of vertical wrapping.

  In addition, since the adhesive is applied to one side of the first resin tape 3, the first resin tapes 3 are bonded to each other at the overlapping portion of the first resin tape 3 wound spirally, It fixes so that the winding by the 1st resin tape 3 may not loosen. Further, when the adhesive is applied to the inner side of the first resin tape 3, the adhesive directly contacts the two insulated wires 2 when the first resin tape 3 is wound, so that the adhesive is more firmly fixed. The When the adhesive is applied to the outside of the first resin tape 3, the shield tape 4 wound around the outside of the first resin tape 3 is adhered to the first resin tape 3 with the adhesive, so that the insulated wire 2 On the other hand, the shield tape 4 is indirectly bonded, and the insulated wire 2 is fixed by the shield tape 4.

  Further, since the shield tape 4 is wound vertically on the outer side of the first resin tape 3, the electrical characteristics can be improved as compared with the case of horizontal winding (when a high frequency signal is transmitted, a specific wavelength is increased). The signal attenuation does not suddenly increase). Further, since the shield tape 4 is wound so that the metal layer 4a is disposed on the outer side and the drain wire 5 is provided on the outer side of the shield tape 4, the drain wire 5 does not exist inside the shield tape 4. The resin tape surface of the shield tape 4 can be adhered to the inner first resin tape 3 without a gap.

  If the drain wire 5 is arranged inside the shield tape 4, the inside of the shield tape 4 is convex at the location of the drain wire 5, and this location (via the first resin tape 3) is the insulated wire 2. It does not adhere to. On the other hand, in the present embodiment, since the drain wire 5 is arranged outside the shield tape 4, there is no convex portion, and therefore the degree of adhesion to the insulated wire 2 (via the first resin tape 3). Is good. Thereby, the dielectric constant in the shield tape 4 is stabilized, and the insertion loss of the two-core parallel cable 1 can be reduced. In addition, as shown in FIG. 2, when the two drain wires 5 are arranged symmetrically, the insulated wires 2 are crushed symmetrically by pressing from the respective drain wires 5. Does not become asymmetric. Thereby, the stability of the dielectric constant in the shield tape 4 is further increased. As a result, the shielding effect of the shield tape 4 on the insulated wire (signal line) 2 is stabilized, and the common mode output amount (Scd21) with respect to the differential mode input signal can be reduced.

  Further, since the jacket layer 6 (second resin tapes 6a and 6b) is provided around the shield tape 4 and the drain wire 5, the shield tape 4 can be insulated and prevented from being contaminated from the outside. The cable can be water resistant. In addition, the second resin tapes 6 a and 6 b are wound so that the metal layer 4 a of the shield tape 4 and the drain wire 5 arranged outside the shield tape 4 are electrically extended over the entire length of the two-core parallel cable 1. Secure contact. When two drain wires 5 are arranged, they are arranged in a symmetrical position with respect to the insulated wire 2, so that the insulator 22 of the insulated wire 2 is not crushed in the same way and becomes asymmetrical. Is stable. The second resin tape is preferably spirally wound (laterally wound). When at least one of the second resin tapes 6 a and 6 b is wound in the opposite direction to the first resin tape 3, it is possible to make the insulated wires 2 difficult to be twisted.

(Second embodiment)
As shown in FIGS. 3 and 4, the two-core parallel cable 1 </ b> A of the second embodiment includes a conductive tape 7 between the shield tape 4 and the drain wire 5. Since parts other than the conductive tape 7 in the two-core parallel cable 1A are the same as those of the two-core parallel cable 1 of the first embodiment described above, the same reference numerals are given and descriptions thereof are omitted.

  The conductive tape 7 is wound around the outer periphery of the shield tape 4 in a spiral shape (lateral winding). The conductive tape 7 is a tape-shaped resin (for example, PET) 7a having tape-shaped metals (for example, copper or aluminum) 7b and 7c attached to both surfaces thereof. Note that one surface of the tape-shaped resin 7a may be formed by vapor-depositing metal without using the tape-shaped metal 7b or 7c.

  The conductive tape 7 is wound so that a part of the conductive tape 7 overlaps. For this reason, the tape-like metal 7b on the inner surface of the conductive tape 7 and the tape-like metal 7c on the outer surface are in contact with each other at the portion where the conductive tapes 7 overlap each other. The thickness of the metal 7b is 0.01 μm to 50 μm, and the metal is deposited on the tape-shaped resin 7a or the metal foil is pasted on the tape-shaped resin 7b. The conductive tape 7 has a width of 2 mm to 10 mm and a thickness of 12 μm to 70 μm. And the winding pitch is 1 mm-10 mm, and it winds so that a part of conductive tape 7 may overlap with the pitch smaller than the width | variety of the conductive tape 7 as mentioned above. Thereby, the tape-shaped metals 7b and 7c are electrically connected. In the example of FIG. 3, the winding direction in which the conductive tape 7 is wound is the same direction as the winding direction of the first resin tape 3, but may be the opposite direction.

  Further, the conductive tape 7 has an adhesive on the surface of the tape-like metal 7b on the inner surface, for example, in a zebra shape or a polka dot shape, and the portion not attached with the adhesive contacts the shield tape 4. ing. Thereby, the metal layer 4a of the shield tape 4 and the tape-like metal 7b are electrically connected.

  Further, in the two-core parallel cable 1A of the second embodiment, the drain wire 5 is vertically attached between the conductive tape 7 and the second resin tape 6a, and the tape-like metal 7c on the outer surface of the conductive tape 7 is provided. In electrical contact. The second resin tape may be wound only by one sheet instead of by two sheets. As described above, since the tape-like metals 7b and 7c are electrically connected, the metal layer 4a of the shield tape 4 and the tape-like metal 7c on the outer surface of the conductive tape 7 are electrically connected. The Thereby, in the two-core parallel cable 1A, the shield tape 4 and the drain wire 5 are electrically connected. The position of the drain line is not limited to the position shown in FIG. For example, one drain line is arranged above and below the shielding tape so as to come into contact with the shielding tape 4 at a position rotated by 90 ° from the position shown in FIG. Also good.

  In the two-core parallel cable 1A of the second embodiment, since the conductive tape 7 is wound spirally (laterally) around the outer periphery of the shield tape 4, the shield tape 4 is less prone to wrinkles, and the insulated wire by the shield tape 4 is insulated. It is difficult for the (signal line) 2 to have a variation in shielding effect. Therefore, it is possible to reduce the variation while reducing the common mode output amount (Scd21) with respect to the differential mode input signal.

An analysis result of the mode conversion amount (Scd21) in the two-core parallel cable of the example and the comparative example will be described.
Note that Scd21 is a conversion amount from the operation mode to the common mode in port 1 to port 2, and is one of the mixed mode S parameters. In a compliance test of a USB cable (for example, USB 3.0), it is set to −20 dB / m or less.
In the following analysis, when a high frequency of 20 GHz or more is transmitted to a 3 m long twin-core parallel cable, the maximum value of Scd21 value is -20 dB / m or less, and that of -25 dB / m or less is considered excellent. Judged. Moreover, the thing whose maximum value of Scd21 value is larger than -20 dB / m was determined to be defective.

Example 1
The configuration of the two-core parallel cable of Example 1 is the configuration of the first embodiment shown in FIG. 2 and was created as follows.
A wire in which two insulated wires 2 having a diameter of 0.96 mm and having a signal conductor 21 of AWG 30 were arranged in parallel was used. A first resin tape 3 having a thickness of 12 μm around the insulated wire 2 (with an adhesive applied inside) is spirally wound left as shown in FIG. 1 and a copper metal layer 4a (thickness) The shield tape 4 having a thickness of 21 μm provided with a thickness of 8 μm was vertically wound around the outer side of the first resin tape 3 as shown in FIG. 1 so that the metal layer 4a was arranged on the outer side. Two drain wires 5 are vertically arranged on both sides of the insulated wire 2 outside the shield tape 4 (as shown in FIG. 2). Two layers of the second resin tape 6a (thickness 12 μm) and 6b (thickness 12 μm) around the shield tape 4 and the drain wire 5 are spirally wound in a right-handed manner as shown in FIG. A jacket layer 6 was obtained.
ScF21 was measured by transmitting a high frequency of 20 GHz or more as a length of 3 m of the two-core parallel cable of Example 1 having the above configuration.
As a result, the maximum Scd21 value was −25 dB / 3 m or less (value per measurement length), and the quality of the two-core parallel cable of Example 1 was determined to be excellent.

(Example 2)
The configuration of the two-core parallel cable of Example 2 is the configuration of the first embodiment shown in FIG. 2 and was created as follows.
The insulated wire 2 has the same configuration as in Example 1. The first resin tape 3 (same as in Example 1) was spirally wound around the insulated wire 2 in a right-handed direction opposite to that in FIG. The shield tape 4 and the drain wire 5 were configured in the same manner as in Example 1. Two layers of the second resin tapes 6a and 6b (jacket layer) around the shield tape 4 and the drain wire 5 were spirally wound in the left direction in the opposite direction to FIG. The thickness and diameter of each part are the same as in the first embodiment.
ScF21 was measured by transmitting a high frequency of 20 GHz or more as a length of 3 m of the two-core parallel cable of Example 2 having the above configuration.
As a result of analysis, the maximum Scd21 value was −25 dB / 3 m or less, and the quality of the twin-core parallel cable of Example 2 was determined to be excellent.

(Example 3)
The configuration of the two-core parallel cable of Example 3 is the configuration of the first embodiment shown in FIG. 2 except for the jacket layer 6, and was prepared as follows.
The jacket layer 6 was formed by extruding thermoplastic polyvinyl chloride (the thickness of the jacket layer 6 was 24 μm). Other configurations were made in the same manner as in Example 1. The thickness and diameter of each of the above parts are the same as those in Example 1 except for the thickness of the jacket layer 6.
As the length of the two-core parallel cable of Example 3 having the above-described configuration of 3 m, a high frequency of 20 GHz or more was transmitted, and the Scd21 was analyzed.
As a result of the analysis, the maximum value of the Scd21 value was −20 dB / 3 m or less, and the quality of the two-core parallel cable of Example 3 was determined to be good.

Example 4
The configuration of the two-core parallel cable of Example 4 is the configuration of the second embodiment shown in FIG. 4 and was created as follows.
Except for the conductive tape 7, the configuration was the same as in Example 1. As the conductive tape 7, a tape-shaped resin (PET) 7a having a width of 10 mm and a thickness of 12 μm and tape-shaped metals (copper) 7 b and 7 c having a thickness of 10 μm were pasted on both surfaces. The conductive tape 7 was spirally wound around the outer periphery of the shield tape 4 with a winding pitch of 5 mm in the left-handed manner (the same direction as the winding direction of the first resin tape 3).
Ten twin-core parallel cables of Example 4 having the above-described configuration were prepared, each having a length of 3 m, transmitting a high frequency of 1 to 20 GHz, and measuring Scd21.
And when the pass / fail judgment which makes the case where the maximum value of Scd21 is -30dB / 3m or less was performed, all 10 examples passed. For comparison, when the above pass / fail judgment was performed for Example 1 as well, 7 out of 10 passed.

(Comparative Example 1)
The first resin tape 3 is not provided (not wound) around the insulated wire 2. Other configurations were made in the same manner as in Example 1.
As a length of 3 m of the two-core parallel cable of Comparative Example 1 having the above-described configuration, a high frequency of 20 GHz or more was transmitted, and Scd21 was analyzed as described above.
As a result of the analysis, the maximum value of the Scd21 value was larger than −20 dB / 3 m, and the quality of the two-core parallel cable of Comparative Example 1 was determined to be poor.

  While the invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. In addition, the number, position, shape, and the like of the constituent members described above are not limited to the above-described embodiments, and can be changed to a number, position, shape, and the like that are suitable for carrying out the present invention.

DESCRIPTION OF SYMBOLS 1 Two-core parallel cable 2 Insulated electric wire 3 1st resin tape 4 Shield tape 4a Metal layer 5 Drain wire 5c Center point 6 Jacket layer 6a, 6b Second resin tape 7 Conductive tape 7a Tape-shaped resin 7b, 7c Tape-shaped metal 21 signal conductor 21c center point 22 insulator C straight line

Claims (6)

A pair of insulated wires arranged in parallel in contact with each other;
A first resin tape wound around the pair of insulated wires;
A shield tape that is wound vertically on the outside of the first resin tape and includes a metal layer;
Two-core parallel cable with Having a drain wire outside the shield tape;
The two-core parallel cable according to claim 1, wherein the drain wire is disposed so as to be electrically connected to the metal layer of the shield tape.   The two-core parallel cable according to claim 2, further comprising a jacket layer provided around the shield tape and the drain wire. Having a conductive tape spirally wound on the outside of the shield tape;
The drain line is disposed outside the conductive tape so as to be electrically connected to the conductive tape and the shield tape,
The two-core parallel cable according to claim 3, wherein the jacket layer is provided around the conductive tape and the drain wire.   The two-core parallel cable according to claim 3 or 4, wherein the jacket layer is a layer formed by winding a second resin tape around the shield tape and the drain wire.   The two-core parallel cable according to claim 5, wherein a winding direction in which the second resin tape is wound is opposite to a winding direction of the first resin tape.

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