JP2002231063A - Shielded flat cable and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shielded flat cable that enables to connect steadily the grounding conductor wire to the shielding layer without requiring a complicated work process, and its manufacturing method. SOLUTION: The flat cable body 1 is structured by embedding a plurality of conductor wires 12 excluding the grounding conductor between the insulating layers 11, 12. A grounding conductor wire 5 is arranged on the surface of this flat cable body 1 and the grounding conductor wire 5 is covered by a shielding tape 2 together with the flat cable body 1. The top end of the conductor wire 12 of the flat cable body 1 is adhered to a reinforcing plate 4 for connector connection at the same time as the top end of the grounding conductor wire 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to various information devices,
The present invention relates to a shielded flat cable used in communication equipment and the like and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, flat cables have been used as signal transmission cables for various information devices and communication devices. This type of flat cable requires shielding against electromagnetic waves, and various shielded flat cables have been developed and used. For example, a flat cable main body is made by laminating an insulating film with a plurality of conductor wires interposed therebetween, and by covering the periphery with a shield tape, a shielded flat cable is obtained. For example, a method of using a conductive adhesive containing a metal filler as a shield layer of a shield tape,
It is disclosed in JP-A-6-283053.

[0003]

In order to bring only the ground conductor of the flat cable covered with the insulating layer into contact with the shield layer of the shield tape, it is necessary to selectively form a hole in the ground conductor. is necessary. Specifically, in order to remove the upper insulating layer of the ground conductor wire, a discard pattern (sacrificial layer) is previously interposed on the ground conductor wire when laminating the flat cable body, and the sacrificial layer is peeled off after lamination. Accordingly, a method of cutting off the insulating layer above the ground conductor line, a method of removing the upper insulating layer of the ground conductor line by laser cutting, or the like is used. Then, the shield layer and the ground conductor wire can be electrically connected by winding the seal dope on the exposed ground conductor wire with a conductive adhesive interposed therebetween. However, these methods complicate the processing steps and require special processing equipment, which increases the processing cost of the shielded flat cable. In particular, when the conductor wire pitch becomes fine, it is not easy to reliably expose only the ground conductor wire, and in the method using the sacrifice layer, not only the upper portion of the ground conductor wire but also the There is a possibility that the insulating layer on the adjacent conductor wire may be peeled off.

The present invention has been made in view of the above circumstances, and provides a shielded flat cable and a method of manufacturing the shielded flat cable, which do not require a complicated processing step and reliably connect a ground conductor wire to a shield layer. It is intended to be.

[0005]

A shielded flat cable according to the present invention comprises a flat cable main body in which a plurality of conductor wires are disposed inside an insulating layer, and the flat cable main body covered with the shield layer inside. And a ground conductor wire disposed on the surface of the flat cable main body and sandwiched between the shield tape and the flat cable main body and connected to the shield layer.

According to the present invention, the flat cable main body is buried with a conductor other than the ground conductor, and the ground conductor is
It is arranged between the flat cable main body and the shield tape, and the shield layer and the ground conductor are electrically connected by covering the shield tape. Therefore, unlike the prior art, a processing step of exposing the ground conductor wire by partially removing the insulating layer of the flat cable body is not required, and even if the pitch of the conductor wires is small, the ground conductor wire and the shield layer can be reliably formed. Can be electrically connected.

In the present invention, it is preferable that a reinforcing plate for connector connection is provided at at least one end of the flat cable main body, and the flat cable main body is provided with a flat end together with the end of the conductor wire disposed inside the flat cable main body. The end of the ground conductor wire arranged on the surface of the cable body is connected to the reinforcing plate. Specifically, a method for manufacturing a shielded flat cable according to the present invention for obtaining such a structure includes a step of forming an flat cable body by laminating an insulating layer with a plurality of conductor wires interposed therebetween; Simultaneously connecting the ends of the plurality of conductor wires to a reinforcing plate for connector connection at at least one end of the main body, and connecting a ground conductor wire disposed on the surface of the flat cable main body to the reinforcing plate; Covering the flat cable main body with a shield tape together with the ground conductor wires arranged on the surface thereof.

According to the method of the present invention, a highly reliable shield can be obtained by merely arranging the ground conductor in the reinforcing plate bonding step to the terminal portion without adding a special processing step to the conventional shield flat cable manufacturing step. You can get a flat cable.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a plan view of a shielded flat cable according to an embodiment of the present invention.
And FIG. 4 correspond to AA ′, BB ′ and C in FIG. 1, respectively.
It is a -C 'sectional view. At least one end of the flat cable is provided with a reinforcing plate for connecting a connector. Here, one end provided with such a reinforcing plate is shown.

The flat cable main body 1 is configured by embedding a plurality of conductor wires 12 arranged in parallel between insulating layers 11 and 13. However, the ground cable is not buried in the flat cable body 1 at the position where the ground (GND) conductor should be buried. The ground conductor wire 5 is arranged on the surface of such a flat cable main body 1, and the flat cable main body 1 is covered with the shield tape 2 together with the ground conductor wire 5.

FIG. 3 is a cross-sectional view taken along the line BB 'of FIG. 1 along the position of the ground conductor line 5. FIG. 5 shows an enlarged cross-sectional view of a portion surrounded by a broken line. That is, in the shield tape 2, for example, a metal deposition layer is formed as a shield layer 22 on one surface of a resin film 21 as a tape base material. By forming the conductive adhesive 6 on the surface of the shield layer 22 and winding it around the flat cable main body 1, the ground conductor wire 5 is electrically connected to the shield layer 22 via the conductive adhesive 6. .

A reinforcing plate 4 is connected to at least one end of the flat cable. Specifically, the conductor wire 12 is embedded in the flat cable main body 1 with its end exposed. And these flat cable bodies 1
The end of the conductor wire 12 buried in the flat cable body and the end of the ground conductor wire 5 arranged on the flat cable main body 1 are bonded to the reinforcing plate 4.

A specific manufacturing process is as follows. First, the flat cable main body 1 is manufactured by laminating resin films as the insulating layers 11 and 13 with a plurality of conductor wires 12 excluding the ground conductor wire interposed therebetween. Next, the ground conductor wire 5 is arranged on the flat cable main body 1, and its end is bonded to the reinforcing plate 4 at the same time as the end of the other conductor wire 12 buried. Then, the flat cable main body 1 is covered with the shield tape 2 with the shield layer inside, together with the ground conductor wire 5 arranged thereon.

As described above, according to this embodiment, the grounding conductor is not embedded in the flat cable main body, but the grounding conductor is arranged on the surface of the flat cable main body, and these are covered with the shield tape, and the grounding conductor is grounded. The electrical connection between the conductor wire and the shield layer is made. Therefore, unlike the related art, it is not necessary to form a hole for connecting the ground conductor wire and the shield layer to the flat cable main body, and the processing cost is reduced. In addition, the ground conductor wire and the shield layer can be electrically connected in the shield tape covering process only by arranging the ground conductor wire at the same time in the reinforcing plate bonding process of the existing equipment. Thus, a shielded flat cable can be obtained with high yield and reliability even if the arrangement pitch of the conductor wires is fine.

In the embodiment, as the shield tape,
Although the description has been given of the one having the shield layer formed by vapor deposition, a shield tape having no vapor-deposited layer and using a conductive adhesive containing a metal filler as a shield layer can also be used.

[0016]

As described above, according to the present invention, there is no need to add a special processing step to the conventional manufacturing process of a shielded flat cable, and only by arranging the ground conductor wire in the reinforcing plate bonding step to the terminal portion. Thus, a highly reliable shielded flat cable can be obtained.

[Brief description of the drawings]

FIG. 1 is a plan view of a shielded flat cable according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line A-A 'of FIG.

FIG. 3 is a sectional view taken along line B-B 'of FIG.

FIG. 4 is a sectional view taken along the line C-C 'of FIG.

FIG. 5 is an enlarged sectional view of a broken line portion in FIG. 3;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Flat cable main body, 11, 13 ... Insulation layer, 12
... conductor wire, 2 ... shield tape, 21 ... resin film,
22 ... Shield layer, 4 ... Reinforcement plate, 5 ... Ground conductor wire, 6 ...
Conductive adhesive.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Moritaka Goto 1440, Rokkazaki, Sakura City, Chiba Prefecture, etc. Inside Fujikura Sakura Office (72) Inventor, Hidefumi Otsuka 1440, Rokkazaki, Sakura City, Chiba Prefecture, etc. In-house (72) Inventor Hirotaka Sawada 1440 No.Mitsuzaki, Sakura-shi, Chiba Pref.

Claims (3)

[Claims] 1. A flat cable main body having a plurality of conductor wires disposed inside an insulating layer, a shield tape covering the flat cable main body with a shield layer inside, and a surface of the flat cable main body. A shielded flat cable, comprising: a grounding conductor wire disposed and connected to the shield layer by being sandwiched between the shield tape and a flat cable main body. 2. The flat cable according to claim 1, further comprising a reinforcing plate for connector connection attached to at least one end of the flat cable main body, wherein the flat cable is provided together with an end of a conductor wire disposed inside the flat cable main body. The shielded flat cable according to claim 1, wherein an end of the ground conductor wire disposed on a surface of the main body is connected to the reinforcing plate. 3. A step of forming a flat cable main body by laminating an insulating layer with a plurality of conductor wires interposed therebetween; and forming at least one end of the flat cable main body with ends of the plurality of conductor wires. Connecting the ground conductor wire arranged on the surface of the flat cable main body to the reinforcement plate at the same time as connecting to the reinforcing plate for connecting the connector, and shielding the flat cable main body together with the ground conductor wire arranged on the surface thereof And a step of coating with a tape.