JP2013045618A - Multicore cable assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multicore cable assembly capable of commonly grinding respective drain wires at one time without labors when plural double-core cables are connected to a substrate.SOLUTION: Each double-core cable 10 comprises: insulation cores 12a, 12b insulating and coating center conductors 11a, 11b; a shield member covering the insulation cores 12a, 12b to at least include them; a drain wire 13 contacting the shield member; and a sheath 15 entirely covering them. Then, in a multicore cable assembly according to the present invention, the double-core cables 10 are aligned at a terminal portion, and the center conductors 11a, 11b are electrically connected to signal conductor connection regions 18a, 18b on a substrate 1. The drain wires 13 are folded and electrically connected to a common ground region (illustrated as a grounding member 17) on the substrate 1.

Description

  The present invention relates to a multicore cable assembly in which a multicore cable composed of a plurality of two-core cables is connected to a substrate.

  Conventionally, as a transmission cable used between server computers or between medical instruments, a collective cable capable of transmitting a large-capacity signal has been proposed. This collective cable is configured by arranging a large number of signal lines or signal line pairs in a plurality of layers from the inner peripheral side to the outer peripheral side. The signal line is configured by covering an outer periphery with an insulating coating member, and the signal line pair is a two-core coaxial cable (Twinax) holding a pair of signal lines in parallel.

  Some two-core coaxial cables have a drain line that is vertically attached to a pair of signal lines and grounded at the ends thereof. When a multi-core cable assembly is configured by connecting a plurality of such two-core coaxial cables to a substrate as a connector, it is necessary to electrically connect each drain line. As described in Patent Document 1, each drain line can be configured not to be conductive on the substrate.

  FIG. 4 is a diagram illustrating a state of an end portion of the two-core coaxial cable described in Patent Document 1. 4A is a perspective view in which a metal pipe as a conductive member is put on the end of a two-core coaxial cable, and FIG. 4B is a diagram in which a plurality of the two-core coaxial cables in FIG. It is a top view in the connected state.

  The two-core coaxial cable 50 shown in FIG. 4A includes signal lines 51a and 51b made of substantially parallel conductors and a drain line 53. The outer periphery of the signal lines 51a and 51b is covered with resin covering members 52a and 52b. It is covered. The signal lines 51a and 51b and the drain line 53 are covered with a shield member 54 made of an Al-PET tape in the longitudinal direction. Then, as shown in FIGS. 4A and 4B, the ends of the two-core coaxial cable 50 are cut off by the covering members 52a and 52b and the shield member 54 with, for example, a laser or a cutter, and the signal lines 51a and 51b. Then, extraction is performed so that the end of the drain line 53 is exposed. The ends of the signal lines 51a and 51b and the drain line 53 are connected to the signal line connection tabs 57a and 57b and the ground tab 58 of the connector 56 by soldering or welding, respectively.

  Further, the shield member 54 and the drain are formed by covering the end portions of the two-core coaxial cable 50, that is, the end portions of the covering members 52 a and 52 b and the shield member 54 with a metal pipe 55 made of, for example, copper as a conductive member. The wire 53 and the metal pipe 55 are electrically connected. That is, the common ground of each two-core coaxial cable 50 is taken using the metal pipe 55. The metal pipe 55 is slid in the axial direction and is brought into close contact with the end face of the connector 56. A plurality of other two-core coaxial cables 50 are arranged in parallel and connected in the same manner, and the metal pipe 55 is slid and brought into close contact with the end face of the connector 56, whereby the end face of the shield member 54 is connected to all the signal line pairs. By maintaining the same position, the portion without the shield member 54 is reduced, and the crosstalk resistance is improved.

JP 2004-71384 A

  However, in the technique described in Patent Document 1, it is necessary to attach a conductive member to each two-core cable in order to collectively ground each drain line, which takes time and effort.

  The present invention has been made in view of the above situation, and it is possible to collectively connect each drain line to a common ground without taking time and effort when connecting a plurality of two-core cables to a substrate. It is an object of the present invention to provide a simple multicore cable assembly.

The multi-core cable assembly of the present invention is an assembly in which a multi-core cable composed of a plurality of 2-core cables is connected to a substrate, and each 2-core cable has two insulating cores with a central conductor insulated by a shield member. The drain wire is arranged so as to be in contact with the shield member, and the whole is covered with a jacket.
In the multi-core cable assembly, the two-core cable is arranged in parallel at the terminal portion, the central conductor is electrically connected to the signal conductor connection region provided on the board, and the common conductor provided on the board is provided. A drain line is folded and electrically connected to the ground region.

Also, the drain wire is connected to a rod-like or plate-like ground member that is bridged over the outer sheath of a plurality of two-core cables, and the ground member is connected to the common ground region. Also good.
Here, the grounding member may be configured to have a plurality of two-core cables and the substrate.
The drain wire is preferably bonded to the ground member or the common ground region with a conductive adhesive.

  According to the multicore cable assembly of the present invention, since the drain wire is folded and electrically connected to the common ground region provided on the substrate, it is troublesome to connect a plurality of two-core cables to the substrate. Therefore, the drain lines can be collectively connected to the common ground.

It is sectional drawing which shows the example of the 2 core cable applicable to this invention. It is a figure which shows one structural example of the multi-core cable assembly which concerns on this invention. It is a figure which shows the other structural example of the multi-core cable assembly which concerns on this invention. It is a figure which shows the mode of the edge part of the conventional 2-core coaxial cable.

The multicore cable assembly of the present invention is an assembly in which a multicore cable composed of a plurality of two-core cables is connected to a substrate.
First, an example of a two-core cable applicable to the present invention will be described with reference to FIG.
The two-core cable 10 includes a drain wire 13, a shield member 14, and a jacket 15, together with insulating cores 12 a and 12 b that cover the central conductors 11 a and 11 b.

  As the central conductors 11a and 11b, a conductor such as copper or aluminum, or a single wire or a stranded wire obtained by plating these conductors with silver or tin can be used. Also, when used in the high frequency region, the current is biased to the conductor surface due to the skin effect, and resistance loss due to this is unavoidable. Therefore, a two-layered conductor with a low resistance on the surface side and a high resistance on the center side of the conductor is used. You may make it use.

  The insulating cores 12a and 12b preferably have a coating layer having a dielectric constant as small as possible, such as perfluoroalkoxyalkane (PFA), polytetrafluoroethylene (PTFE), perfluoroethylenepropylene copolymer (FEP), polyethylene, polypropylene, etc. Is used. The two insulating cores 12a and 12b may be twisted together or may be aligned in parallel without being twisted. A twisted pair cable is formed as the two-core cable 10 by the former, and a two-core parallel cable is formed as the two-core cable 10 by the latter.

  The drain wire 13 is a conducting wire such as, for example, annealed copper, tin-plated annealed copper, copper alloy, aluminum, aluminum alloy, or the like provided so as to contact the shield member 14. The drain line 13 is vertically attached to the insulating cores 12a and 12b.

  The shield member 14 is a member that covers at least two insulating cores 12a and 12b, and is provided by, for example, winding a shield tape such as Al-PET in a spiral shape. A shield tape in which a resin other than PET is bonded to a metal other than aluminum may be used. The metal may be directed toward the insulating cores 12 a and 12 b or toward the outer jacket 15, but the drain wire 13 is provided so as to contact the metal of the shield member 14. When facing the insulating cores 12a and 12b, the shield member 14 is provided so as to cover the drain wire 13 with the valley portion where the insulating cores 12a and 12b are arranged vertically as shown in FIG. At this time, when the insulating cores 12a and 12b are twisted together, twisting may be stabilized by twisting the drain wire 13 together with the insulating cores 12a and 12b. When the metal of the shield member 14 is directed to the outer cover 15 side, the insulating cores 12a and 12b are covered with the shield member 14 as shown in FIG.

  The outer cover 15 covers the two insulating cores 12a and 12b, the shield member 14, and the drain wire 13 all together, and examples thereof include PET tape and extrusion-coated fluororesin.

Next, a configuration example of the multicore cable assembly according to the present invention will be described with reference to FIGS. 2 and 3. 2A and 3A are perspective views of the assembly, and FIGS. 2B and 3B are vertical sectional views of the assembly.
The multi-core cable assembly of the configuration example shown in FIGS. 2 and 3 is an assembly in which multi-core cables composed of four 2-core cables 10 are connected in parallel to a substrate 1 such as polyimide or glass epoxy.

  2 and 3, the shield member 14 is omitted for the sake of convenience. However, as illustrated in FIGS. 1A and 1B, the shield member 14 is present inside the jacket 15 and is basically shown. Further, it is assumed that the end is cut at the same position as the outer cover 15 or slightly longer (with a little exposure from the outer cover 15). 2 and 3 show examples in which four two-core cables 10 are connected to the substrate 1. However, the number of the two-core cables 10 is not limited to four and may be plural.

This multi-core cable assembly is formed by connecting four two-core cables 10 to the substrate 1. In this case, first, the jacket 15 is removed, and the drain wire 13, the insulating cores 12 a and 12 b, The center conductors 11a and 11b are exposed, and the end portions (end portions) are arranged in parallel. The shield member 14 is cut so that the end thereof is at the same position as the outer cover 15 or slightly exposed.
The central conductors 11a and 11b of the insulating cores 12a and 12b are electrically connected to the signal conductor connection regions 18a and 18b provided on the substrate 1, respectively. The signal conductor connection regions 18 a and 18 b are exaggerated in FIGS. 2 and 3, but are provided as signal line connection conductive patterns themselves on the substrate 1. Instead, a signal conductor connection region may be provided as a conductor connected to the conductive pattern.

  Further, the drain line 13 is folded back and electrically connected to the ground member 17. The common ground regions 16a, 16b or 26a, 26b are provided as conductors connected to the conductive pattern in regions that are common ground contacts with the drain line 13. Instead, the common ground regions 16a and 16b or 26a and 26b may be provided as the ground conductive pattern on the substrate 1 itself. Here, although the drain wire 13 can be connected with low-temperature solder or general solder, it is preferably bonded to the ground member 17 with a conductive adhesive. The ground member 17 is soldered or adhered to the common ground regions 16a, 16b or 26a, 26b with a conductive adhesive, and the drain line 13 is dropped to the ground circuit of the conductive pattern of the substrate 1.

  In the present invention, the drain line 13 is folded back and connected to the ground member 17 as described above. As a result, the signal conductor connection regions 18a and 18b are provided so as to be positioned closer to the end of the two-core cable 10 than the common ground regions 16a and 16b or 26a and 26b. That is, the drain line 13 is electrically connected to the common ground regions 16a, 16b or 26a, 26b of the substrate 1 via the ground member 17 closer to the middle of the cable than the center conductors 11a, 11b.

  This positional relationship will be described with respect to the configuration example of FIG. In this configuration example, the grounding member 17 is a bar-shaped or plate-shaped ground bar that is bridged over the jacket 15 of the four two-core cables 10. The ground bar is on the opposite side of the substrate 1 when viewed from the two-core cable 10 (the ground bar is placed on the two-core cable 10). The ground member 17 may be one in which a conductive foil such as a copper foil is attached to the two-core cable 10 with an adhesive. The common ground regions 16 a and 16 b in this example are bridge piers and have a height that is about the thickness of the two-core cable 10. Both ends of the ground bar are connected to the piers 16a and 16b. Thereby, the drain line 13 is electrically connected to the conductive pattern of the substrate 1.

  As shown in FIG. 2, each drain line 13 is connected to the ground member 17 in a state where the drain line 13 is folded back from the position led out from the two-core cable 10 to the side opposite to the lead-out direction. More specifically, the drain wires 13 of the four two-core cables 10 which are folded back in parallel with the same pitch P are electrically connected to each other by bonding them to the ground member 17 with a conductive adhesive. This connection is possible without using a conductive adhesive as described above.

  Thus, by turning back each drain line 13 from the lead-out position, the contact point of the drain line 13 (the contact point on the grounding member 17 in FIG. 2B) is along the contact point of the center conductors 11a and 11b and the cable length. Different positions. Thereby, the drain lines 13 can be electrically connected to the conductive pattern of the substrate 1 in a lump.

  Next, the reason why it is preferable to perform electrical connection using the grounding member 17 and a conductive adhesive will be described. The main reason is that it is necessary to suppress insulation exposure as much as possible to maintain electrical characteristics. Even if the length of the insulating exposed portion is extremely short, the drain line 13 can be easily connected to the conductive pattern if the drain line 13 is folded and placed on the jacket 15. By using a conductive adhesive, the outer jacket 15 is not damaged by the heat at the time of connection. When connecting the drain line 13 and the ground bar with solder, it is preferable to use low-temperature solder. It is also possible to apply a conductive foil tape with an adhesive on the jacket 15 of the two-core cable 10 and solder-connect the drain wire 13 thereto. If the adhesive layer is thick, there is little risk of damage to the jacket 15 due to the heat of soldering.

In order to facilitate alignment as shown in FIG. 2, before drain lines are folded, the four drain lines 13 are placed in a grooved plate and aligned (with tape or the like so as not to come out of the grooves). The plurality of drain lines may be folded back with the plate temporarily attached.
In the configuration example of FIG. 2, it is preferable to connect the drain line 13 and the ground member 17 first. The order of the subsequent connection of the center conductors 11a and 11b to the signal conductor connection regions 18a and 18b and the connection of the ground member 17 to the piers 16a and 16b are not particularly limited.

  Next, the positional relationship described above will be described with respect to the configuration example of FIG. The multi-core cable assembly of the configuration example shown in FIG. 3 has a structure in which the four 2-core cables 10 and the grounding member 17 are combined in the configuration example of FIG. Hereinafter, the description of the same part as the configuration example of FIG. 2 is omitted.

  More specifically, in the configuration example of FIG. 3, the grounding member 27 is provided between the four two-core cables 10 and the substrate 1. The ground member 27 may be the same member as the ground member 17 of FIG. The grounding member 27 in this example is connected to the ground conductive pattern of the substrate 1 through the common ground regions (bridge piers) 26a and 26b.

  In this configuration example, the drain wire 13 is connected to the ground member 27 in a state where the drain wire 13 is folded back from the position led out from the two-core cable 10 to the side opposite to the lead-out direction. However, in this configuration example, unlike the configuration example of FIG. 2, since the ground member 27 is between the two-core cable 10 and the substrate 1, the drain wire 13 is folded back toward the substrate 1 when viewed from the two-core cable 10. It will be. In this connection, it is preferable to use a conductive adhesive as described for the connection between the ground member 17 and the drain wire 13.

  The bridge piers 26a and 26b only need to have a height that is the sum of the thickness of the drain wire 13 and the thickness of a connecting agent such as a conductive adhesive. The piers 26a and 26b in FIG. 3 are lower than the piers 16a and 16b in FIG. 2 by subtracting the thickness of the connection portion of the common ground region and the drain line 13 from the thickness of the two-core cable 10. .

  In the configuration example of FIG. 3, unlike the connection procedure of the configuration example of FIG. 2, the drain wire 13 is first connected to the ground member 27, and then the ground member 27 is placed on the substrate 1 side. The connection to the conductor connection regions 18a and 18b and the connection to the piers 26a and 26b of the ground member 27 may be performed. Also in this case, the order of connection of the grounding member 27 to the piers 26a and 26b and finally connection of the center conductors 11a and 11b to the signal conductor connection regions 18a and 18b is not limited.

It is also possible to employ a configuration in which the bent drain line 13 is electrically connected to the ground conductive pattern on the substrate 1 in the same manner as shown in FIG. In that case, it will be in the state which removed the grounding member 27 and the pier part 26a in FIG.3 (B).
As yet another example, the drain wire 13 may be sandwiched between the ground member 27 and the jacket 15, and the ground member 27 and the jacket 15 may be bonded with a conductive adhesive.

  As described above, according to the multi-core cable assembly of the present invention, since the drain wire is folded and electrically connected to the ground member, when connecting a plurality of two-core cables to the substrate in parallel, Unlike the technique described in Patent Document 1, a conductive member is not required on the two-core cable side, and the connection is not time-consuming. Furthermore, in the technique described in Patent Document 1, since the contact of the drain line and the contact of the central conductor are arranged in parallel, the drain lines cannot be grounded together at the same time. Accordingly, since they are not arranged in parallel, the drain lines can be collectively grounded. In addition, since the drain line is connected to the common ground region with the conductive adhesive, the insulator of the jacket is not damaged by heat.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate, 10 ... 2 core cable, 11a, 11b ... Center conductor, 12a, 12b ... Insulating core, 13 ... Drain wire, 14 ... Shield member, 15 ... Outer casing, 16a, 16b, 26a, 26b ... Common ground area | region (Bridge pier part), 17, 27 ... Grounding member, 18a, 18b ... Signal conductor connection region.

Claims (4)

A multi-core cable assembly in which a multi-core cable comprising a plurality of two-core cables is connected to a substrate,
The two-core cable has two drain cores arranged so as to be in contact with the shield member by covering two of the insulating cores with the central conductor insulated and covered with the shield member.
The two-core cable is arranged in parallel at a terminal portion, the central conductor is electrically connected to a signal conductor connection region provided on the substrate, and the drain wire is connected to a common ground region provided on the substrate. Are folded and electrically connected to each other.   The drain wire is connected to a rod-shaped or plate-shaped grounding member bridged over the jacket of the plurality of two-core cables, and the grounding member is connected to the common ground region. The multi-core cable assembly according to claim 1.   The multi-core cable assembly according to claim 2, wherein the grounding member is provided between the plurality of two-core cables and the substrate.   4. The multi-core cable assembly according to claim 1, wherein the drain line is bonded to the ground member or the common ground region with a conductive adhesive. 5.

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