JPS61165972A - Cable unit for interface - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an interface bus cable device, and in particular, a connector including a plug or a receptacle is connected to the end of a multi-core cable covered with a shield braid, and a plurality of core wires are connected to an end of a multi-core cable covered with a shield braid. The present invention relates to an interface bus cable device, such as one used to connect a personal computer interface.

Generally, computers are configured to allow multiple terminals such as line printers and floppy disks to be added.
The computer, computer, and terminal are connected by a bus cable assembly.

By the way, recently, computers have come to be used not only in the field of measuring instruments but also in a wide range of fields. In particular, personal computers are increasingly being brought into homes for personal use. However, when a personal computer is brought into the home, it can cause interference with radio receivers, television receivers, etc. This is because harmonic components of logic signals used in computers or clock signals of, for example, 1 to 4 MHz leak to the outside and enter television receivers. To prevent this, computers or terminals are shielded, and cables used in bus cable assemblies are also shielded with a shield braid. However, although the ends of the bus cable assemblies are connected to connectors, no safety measures have been taken at the connecting portions of the connectors.

The applicant of the present application has focused on this problem and conducted an experiment regarding leakage at the connector connection portion of the bus cable assembly, and the results will be described below.

FIG. 1 is an external view showing the main parts of a bus cable assembly, which is the background of this invention. In particular, FIG. 1(a) shows a front view, and FIG. A plan view partially cut along line bb is shown.

In the figure, a multicore cable 1 has, for example, 24 core wires 1.
1, a shield braid 12 covering the shield braid 12, and a covering 13 covering the shield braid 12. A cable inlet 35 provided at the tail end of the connector cover 320 of the connector 5 is provided on the outer periphery of the coating 16 at the end of the multicore cable 1.
The clamp fitting 19 is made of two metal plates of the same shape bent into a substantially U-shape to prevent the multi-core cable 1 introduced from the connector 5 from detaching from the connector 5. It is worn. The connector 5 includes a plurality of contacts 31 of a plug or receptacle, a contact cover 55 made of all-steel that surrounds the contacts 51, and a mounting portion 34 formed integrally with the contact cover 35, which are fixed together with screws. Table 1 to be done!
and two connector covers 52 having the same shape. A locking groove 56 for locking the clamp fitting 19 is provided on the inner surface of the connector cover 62.

A core wire 11 of the multicore cable 1 is individually connected to each contact 51 of the connector 5. Note that the shield braid 12 is connected to one of the contacts 51 by a drain wire 14.

FIG. 2 is a diagram for explaining the measurement method for measuring the stiffness characteristics of the bus cable assembly shown in FIG. 1, and FIG. 3 is a diagram showing the stiffness characteristics as a measurement result. .

First, referring to FIG. 2, place the guide line L1 made of 20 AWG annealed copper wire of 0.813 Imφ and the bus cable assembly shown in FIG. They are arranged parallel to each other with an interval of 20 spaces between them.

A signal generator S is connected to one end of the guide line L via a resistor R1.
Give a 200 MHz signal from G. The other end of this induction line L1 is, for example, a 50 ohm resistor R2.
Ground through.

On the other hand, a voltmeter LM is connected to the contact 51 of the connector 6 connected to one end of the bus cable assembly through a 50 ohm resistor R6, and the contact 31 of the connector 5 at the other end is connected through a 50 ohm resistor R4. Ground. Note that the contacts connected to the shield braid 12 at both ends are grounded.

In the measurement circuit configured as described above, when a signal with a voltage V of 0 to 200 MHz is applied from the signal generator SG to the guide line L1, the multicore cable 1 is shielded by the shield braid 12, so this multicore cable 1 itself will not be contaminated with leakage. However, since no protection measures have been taken at the connection between the connector 2 and the multicore cable 1 shown in Figure 1, leakage may occur in this area and the voltage displayed on the voltmeter will be LMKV2. . Using these voltages v1 and v2, the shielding effect is calculated from the following equation.

Shielding effect = 20 Lot -CdB) Based on the above formula, calculate each shielding effect in the signal from 0 to 200 tVfHz. Then, as shown by the dotted line a in FIG. 5, for example, in the vicinity of 120 MHz, a shielding effect of only about 30 dB can be obtained. That is,
For example, the bus cable assembly shown in FIG.
If a harmonic component due to a clock signal or logic signal in the vicinity of MHz flows, the harmonic component leaks to the outside and causes radio wave interference in, for example, a radio FM receiver or a television receiver.

Therefore, the main object of the present invention is to provide an interface cable device in which a multicore cable is connected to a connector plug or a plurality of contacts of a receptacle, in which a core wire of a multicore cable is connected to a connector plug or a plurality of contacts of a receptacle. Interface bus cable device lyi with measures against interference in parts
It is to provide.

To summarize the present invention, a member is provided that surrounds a connecting portion between each core wire of a multicore cable and a plurality of contacts, and is electrically connected to a conductor surrounding the plurality of contacts by soldering. The shielding member is connected to the shield braid of the multicore cable to enhance the shielding effect, and the connecting portion is protected with a glass tape.

The above objects and other objects and features of the present invention will become more apparent from the detailed description given below with reference to the drawings.

FIG. 4 is an external view showing the main parts of a bus cable assembly according to an embodiment of the present invention, in particular, FIG. 4(a) shows a front view, and FIG. 4(b) shows a front view. ) K in b-
A plan view partially cut along line b is shown.

Further, FIG. 5 shows a plan view of a restraining member used in an embodiment of the present invention.

In FIG. 4, a bus cable assembly consisting of a multicore cable 1 and a connector 5 is constructed in the same manner as in FIG. In addition, a ring-shaped elastic body 57 made of plastic as a cushioning material for supporting the hinge fitting 19 is installed inside the locking groove 36 provided on the inner surface of the connector cover 52, and this elastic body 37 is not provided. This eliminates rattling of the clamp fitting 19 due to the gap existing between the clamp fitting 19 and the connector cover 32, and even if the multi-core cable 1 is twisted, the force is applied to the connection between each core wire 11 and the contact 31. This prevents poor contact, disconnection, etc. from occurring at the connection part.

A cable that surrounds the connection portion between each core wire of the multicore cable 1 and the plurality of contacts of the cable assembly configured as shown in Fig. 1, and electrically contacts the contact cover that surrounds the plurality of contacts. The member 7 may be, for example, a thin gold bullion wire knitted into a tape shape.
Alternatively, a conductive cloth-like material, so-called "exband metal 1", is used, which is made into a mesh-like net by making a plurality of vertical cuts in a metal tape and stretching the tape in the width direction of the tape. Since a shaped body is used, workability during shielding work is extremely good.

Next, a method of attaching the shield member 7 made of expanded metal to the connector 3 will be explained. First, each core wire 11 of the multicore cable 1 is connected to each contact 51 of the plug of the connector 3 shown in FIG. 4 by soldering. Protect and reinforce the connection area where each core wire is connected with adhesive glass tape.The connection area between the core wire 11 of the multi-core cable and the contact 61 is made by making a notch 71 shown in the fifth ring in the old spunt metal such as copper. Attach the shielding member 7 so as to surround it with the contents. At this time, the shielding member 7 is brought into contact with a part of the contact cover 55 and soldered there. Furthermore, on the multi-core cable 1 side of the shielding member 7, the shield braid 12 of the multi-core cable 1 is sandwiched and bound with a bind wire 72 made of copper or the like, and the expanded metal as the shield member 7 is attached to the shield braid 12. Connect electrically.

As a result, the connection portion between the contact 61 and each core wire 11 of the multicore cable 1 is covered by the shielding member 7 and electrically connected to the contact cover 35 and the shielding member 7. Further, a connector cover 52 made of synthetic resin such as vinyl and having the same shape on the front and back is fixed together with screws so as to cover the entirety of the shielding member 7.

When the shielding characteristics of the bus cable assembly constructed as described above were measured using the measuring circuit shown in FIG. 2, the shielding characteristics were as shown by the solid line shown in FIG. 5. That is, as is clear from FIG. 3, there was almost no leakage at frequencies below 120 M, H, z, which was at the measurement limit shown by the solid line C in FIG. And around j50MHz, it is only 60d.
It was possible to make it so that leakage of level B was unlikely to occur.

Further, by doubling the multicore cable 107 and the shield braid 12, the shielding effect can be further enhanced.

In the above-mentioned embodiment, the stiffening member 7 is constructed using a tape made of woven copper wire, but the material is not limited to this, and metal tape, acrylic, polyester, nylon, polypropylene can be used. The connecting portion 8 is covered with a metal plating cloth made by plating a metal such as copper, silver, or nickel by chemical plating, electroplating, vacuum deposition, gold JIF irradiation, ion floating, sputtering, etc. on a woven fabric or nonwoven fabric such as A similar effect can be obtained by soldering or binding to the shield braid 12 with a copper wire. Note that the shielding member 7 may be not only a conductive cloth-like material but also a metal plate processed to make it easy to attach.

As described above, according to the present invention, electrical connection is made by soldering to a metal contact cover that surrounds the connection portion between each core wire of a multicore cable and a plurality of contacts of a plug of a connector or a plurality of contacts of a receptacle, and covers the contacts. By providing a barrier member in contact with the connector and connecting the barrier member to the shield braid of the multi-core cable, leakage at the connecting portion of the connector can be prevented.

Furthermore, since the connection part is protected with glass tape, excess solder that flows out during soldering may adhere to the connection part and cause problems (for example, abnormal connection between contacts, breakdown of core wire insulation, etc.). ) can be reliably prevented and a stable product can be obtained.

[Brief explanation of the drawing]

FIG. 1 is an external view of the main parts of a bus cable assembly, which is the background of this invention. FIG. 2 is a diagram for explaining a method of measuring the shielding characteristics of the bus cable assembly shown in FIG. 1. FIG. 5 is a diagram showing the blocking characteristics of a conventional bus cable assembly and an embodiment of the present invention. FIG. 4 is an external view of a main part of an embodiment of the present invention, and FIG. 5 is a plan view of the same shield member. In the figure, 1 is a multicore cable, 11 is a core wire 12 is a shield braid, 5 is a connector, 31 is a contact, 32 is a connector cover, 35 is a contact cover, and 7 is a shield member.

Claims (1)

[Claims] A multicore cable in which a plurality of core wires are covered with a shield braid, a plurality of contacts of a plug or receptacle connected to each core wire of the multicore cable, and a conductive cable surrounding the plurality of contacts. a connector including a body; and a shield braid of the multicore cable, which is provided so as to surround a connecting portion between each core wire of the multicore cable and a plurality of contacts, and to be electrically connected to the conductor by soldering. 1. A bus cable device for an interface, comprising a shielding member to be connected, and further characterized in that the connecting portion is protected with a glass tape.