JP2558327B2 - Cable branch connection formation method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for forming a branch connection of a cable such as a flat cable, and more specifically, for example, a middle portion of a cable for high-speed signal transmission is branched. The present invention relates to a method of forming an electrical branch connection when connecting to a tail portion of a terminal of a connector body for connection.

[Prior Art] In the case of high-speed signal transmission between a main body of a large-sized computer or a peripheral device, connection reliability of a connection portion of a signal line connector is increased, board mounting density is increased, relay boards are reduced, and In order to reduce reflection and crosstalk noise due to impedance mismatch, efforts are being made to reduce the number of connectors by connecting a signal branching connector to the middle portion of a high speed signal cable.

When the middle part of the cable for high-speed signal transmission is branched and connected, for example, as shown in FIG. 7, the cable is cut into two cable parts 101 and 102 to be temporarily discontinuous cable parts 101 and 102, or originally two separate parts. Cable 1
01 and 102 are used to remove the insulating coatings 103 and 104 of the two cable portions 101 and 102 to expose the respective signal lines 105 and 106.
It is known that the ground wire 107, 108 is welded to the tail portion 110 of the signal terminal and the tail portion 111 of the ground terminal of the branch connection connector main body 109 to form a branch connection (for example, actual opening). See Japanese Patent Publication No. 61-114671).

[Problems to be Solved by the Invention] In the case of the conventional technique of this type, it is necessary to substantially cut the cable at the branch connection portion, which is troublesome.
In addition, since it is necessary to connect two wires to each terminal in forming each branch connection, there are many connection points, which may cause connection failure, or it is difficult to avoid trouble. This difficulty is compounded as the number of connectors and / or the number of wires per cable increases.

The present invention has been made in view of the above points, and an object thereof is to provide a branch connection forming method capable of easily and reliably forming a branch connection of a cable.

[Means for Solving the Problem] According to the present invention, the above-described object is to provide an insulating coating of a cable including a signal line and a grounding line at an intermediate portion in the longitudinal direction.
The step of removing the signal line and the ground line at the two locations and exposing the signal line and the ground line at the two locations, and projecting the signal line at one of the exposed locations while keeping each of the signal line and the ground line in a continuous state. And exposing the ground wire at the other exposed portion, bending the cable at the protruding portion of the exposed signal line to overlap the cable portion having the insulation coating, and protruding the exposed signal wire and the exposed ground wire. Electrically connecting the points to the corresponding terminals of the connector.

[Operation and Effect of the Invention] In the branch connection forming method of the present invention, in particular, the insulating coating of the cable including the signal line and the ground line is removed at two locations in the middle portion in the longitudinal direction to remove the signal line and the ground line. With the step of exposing at two locations, and while keeping the signal line and the ground wire in a continuous state, the signal line is projected at one of the exposed locations and the ground wire is projected at the other exposed location. Since there is a step and a step of bending the cable at the protruding portion of the exposed signal line to overlap the cable portion having the insulating coating portion, it is not necessary to cut the cable at the branch connection portion, and the labor involved in the cutting is required. Does not hang. Moreover, in forming each branch connection, each exposed / protruding line of the bent end portion may be connected to the corresponding terminal in a one-to-one relationship, so that the number of connection points can be minimized and a connection failure may occur. Less and saves you the trouble of connecting. Therefore, even if the number of connectors and / or the number of lines per cable is increased, the branch connection of the cables can be easily and reliably formed.

[Embodiment] Next, as a preferred embodiment and a modification of the present invention,
A method for branching and connecting a flat cable will be described with reference to FIGS. 1 to 6. Instead of the flat cable, the cable may be, for example, a thin coaxial cable including one signal line and one ground line.

First, as shown in Fig. 2, the PT of the flat cable 1
The insulation coating 2 made of FE (polytetrafluoroethylene) or the like is removed by, for example, a CO ₂ laser at two locations in the longitudinal intermediate portions A and B indicated by imaginary lines to expose the core wire 3.
The insulating coating may be any other material, for example ETFE
Other fluorine resin such as (ether / tetra / fluoroethylene) and FEP (fluorinated / ethylene / propylene), foamed fluorine resin, or polyolefin such as polyethylene may be used. Also, the removal of the insulating coating may be done by other thermal means, mechanical or chemical means. Although only one core wire 3 is visible in FIG. 2, as can be seen from FIG. 1 shown in a perspective view,
It is composed of a plurality of signal lines 4,5, etc. and a plurality of ground lines 6, 7, 8, 9, 10 etc. provided one on each side of each signal line. Signal line 4,
5, the ground lines 6, 7, 8, 9, 10 and the exposed portions of the core wire 3 representing these as a whole at the portions A and B will be respectively referred to as reference numerals 4 below.
a, 5a, 6a, 7a, 8a, 9a, 10a, 3a, and symbols 4b, 5b, 6b, 7b, 8b, 9
It is represented by b, 10b, 3b (note that in FIGS. 1 to 6 only some of these lines are shown, so there are some that do not have corresponding symbols in the drawings). The lengths C and D of the exposed portions 3a and 3b of the core wire 3 may be the same or one of them may be longer than the other (C> D or C <D).

Next, the signal lines 4 and 5 of the plurality of core wires 3 are exposed to the exposed portion 4
At the same time, push up or push down so that the ground wire 6,7,8,9,10 etc. is projected on the same side at the exposed portions 6b, 7b, 8b, 9b, 10b etc. It is extruded and deformed as shown in FIG. At this time, the lengths C and D between the covering portions 11, 12, and 13 are shortened due to the protrusion at one or the other exposed portion corresponding to each line. Instead of simultaneously projecting the plurality of core wires, the core wires may be divided into several parts. (Note that this protrusion method itself is also described in, for example, US Pat. No. 4,722,692.) Next, in order to bend the cable 1 at the core wire 3a of the exposed portion A, the coating portion of the cable 1 is bent. 12, 13 and exposed core wire 3b
Is rotated in the E direction with respect to the covering portion 11 so that the projecting ground wire portions 6b, ..., 10b and the like are on the outer side, and is rotated in the E direction. As shown in FIG. Cover part 12,13
And the entire exposed portion 3b is laid on the covering portion 11 of the cable.
In FIG. 4, reference numerals 14a and 14b denote exposed portions at the portions A and B of the signal line 14 (not shown in FIG. 1) which should be located at the leftmost end in FIG. , 15b are exposed portions at the portions A, B of the ground line 15 (not shown in FIG. 1) which should be located at the leftmost end in FIG. After this folding,
The signal lines 4,5 and 14 are bent and formed into a shape suitable for connecting to the signal terminals of the connector at the protruding exposed portions 4a, 5a and 14a (here, for the sake of simplification of explanation, the signal lines are formed). The number of signal lines will be described as an example, but the number of signal lines may be four or more or two). By this bending forming, the protruding ends 16 and the like of the signal lines 14a and the like are positioned so that the lower side 17 thereof is substantially flush with the upper surfaces 18 and 19 of the covering portions 12 and 13. At this time, if desired, the ground lines 6, 7, 8, 9, 10, 15 may also be formed into a predetermined shape. This forming may be performed by simply sandwiching it with an appropriate jig or by bending it.

In addition, before or after this forming,
By adjusting the interval between the covering portions 11, 12, 13 to minimize the length of the ground wire 15a and the like in the exposed portion A, the signal line 1 in the exposed portion B
The length such as 4b may be minimized.

Next, as shown in FIG. 5, the exposed portions of the ground wire 6b; 7b, 8
A metal plate 24 for common grounding having openings 20, 21, 22, 23 provided at the portions corresponding to b; 9b, 10b; 15b is placed on the bent body 25 of FIG. 4, and is imagined in FIG. As indicated by the lines, the projecting portions 15b and the like of the ground wire 15 and the like are fixed to the ground plate 24 by soldering 26 and the like and electrically connected. Thereafter, the finger portion 27 extending from both sides or one side of the ground plate 24 and the exposed portion 4 of the signal lines 4,5, 14 are provided.
a, 5a, 14a each of the forming end 16 or the like, soldering tail portions 30a, 31a, 32a, 33a or the like of the corresponding terminals 30, 31, 32, 33 arranged in one row of the connector body 28 or Electrically connected and secured by welding 26 or the like.

In FIG. 1, the signal lines 4a and 5a are shown for the sake of clarity.
While using the protruding end such as a without protruding, the finger part 27 of the ground plate 24 is bent and extended, and the protruding end and the extended end are connected to the terminals 30, 31,
An example in which the tail ends 30a, 31a, 32a of 32 and the like are connected and fixed to the recesses is shown, but as shown in FIG. It is more preferable to mount it on the base and electrically connect and fix it to the tail portion.

Since the cable assembly 35 formed as described above does not need to cut the core wire 3 of the cable 1 when connecting the connector body 28 to the intermediate portion of the cable 1, The number of core wires to be connected to the tail portion is halved compared to the conventional example as shown in FIG. 7, and the man-hours can be reduced and the connection reliability can be improved. Moreover, the exposed portion of the signal line and the ground wire, the respective portions 4b, 5b, 14b and 6a, 7a, 8a,
Since it can be shortened not only in 9a, 10a, 15a, but also in parts 4a, 5a, 14a, etc., noise due to crosstalk in the exposed part of the signal line and impedance in the electrical connection part (branch connection part) and its vicinity It is possible to reduce the reflection of the transmission signal at the branch connection portion due to the variation of the. Further, since the number of connecting portions of this cable assembly is minimized, the cable assembly can be miniaturized and enables high-density mounting.

The cable assembly or branch connecting portion 35 formed as described above is then embedded and fixed in a resin together with the connector main body portion to form a connector 36 as shown in FIG.
Since the entire connector is integrally molded with resin, the connector can be miniaturized. FIG. 6 shows that the cable has the three connectors 36a, 36b, 36c thus formed. In the case of FIG. 6, the three connectors 36a, 36b, 36c are respectively composed of a plurality of boards or mothers constituting a part of the computer main body or peripheral devices thereof through complementary connectors or headers 37a, 37b, 37c, respectively.・
It is directly connected to the boats 38a, 38b, 38c.

It should be noted that the cable assembly 35 or the connector 36 formed as described above can use existing parts as most parts.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view of a branch connecting portion formed by the method of a preferred embodiment according to the present invention, and FIGS.
FIGS. 2, 4, and 5 are explanatory views of a process for forming a branch connection in the figure, FIGS. 4 and 5 are explanatory views of a portion corresponding to a left side view of FIG. 1, and FIG. A cross-sectional explanatory view of a portion corresponding to the line III (however, in the case of the example of FIGS. 2 to 5 is different from the example of FIG. 1 in that the exposed end portion of the signal line is formed), FIG. FIG. 7 is an explanatory view of an example of connecting a connector including a branch connection formed according to the present invention to three mother boards, and FIG. 7 is an explanatory view of a conventional branch connection forming method. 1 …… Cable, 4,5,14 …… Signal line, 6,7,8,9,10,15 …… Grounding wire, 4a, 4b, 5a, 5b, 14a, 14b …… Exposed part of signal line, 6a , 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 15a, 15b …… ground wire exposed part 11,12,13 …… insulating coating part, 30,31,32,33 …… connector body Terminal part.

Claims (1)

(57) [Claims] 1. A step of removing an insulating coating of a cable including a signal wire and a ground wire at two locations in an intermediate portion in the longitudinal direction to expose the signal wire and the ground wire at the two locations, and a signal wire and a ground wire. While keeping each of them in a continuous state, projecting the signal line at one exposed part of the exposed part and projecting the ground line at the other exposed part, and bending the cable at the projected part of the exposed signal line. Branch connection of the cable including the steps of stacking the cable portion having the insulating coating portion and electrically connecting the protruding portion of the exposed signal wire and the protruding portion of the exposed ground wire to the tail portion of the corresponding terminal of the connector body. Forming method.