JP2008004464A - Flat cable with shield - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shielded flat cable which facilitates machining of a shield of the flat cable and offers superior productivity. <P>SOLUTION: According to the shielded flat cable 10', two plane shield members 14 and 14 are glued to both faces of the flat cable 12 which is formed by sheathing a plurality of conductors 16 spaced to be parallel to each other with an insulator 18, and a drain line 16a made conductive to the shield member 14 is exposed along the entire length of the flat cable 12 on one surface thereof. Two plane shield members 14 and 14 are stuck together to be conductive to each other at the ends of the flat cable 12, and the shield member 14 is glued directly to the drain line 16a to be conductive thereto. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a shielded flat cable, and more particularly to a shielded flat cable suitably used for wiring of electrical equipment mounted on OA equipment, home appliances, vehicles such as automobiles, and the like.

  Conventionally, shielded cables have been used for wiring of electrical equipment and the like mounted on vehicles such as OA equipment, home appliances, and automobiles. The shielded cable has a structure having a shield layer on the outer periphery of an electric wire such as a signal line or a power supply line, and is not easily affected by external noise, and it is difficult to emit noise generated by itself.

  Recently, from the viewpoint of space saving and weight reduction, flat cables have been used for the wiring of the above devices and the like. The flat cable has a flat shape as a whole and is excellent in flexibility, and has an advantage that the wiring direction can be freely changed by bending. Also in the flat cable, a shielded flat cable whose outer periphery is covered with a shield layer is used for the purpose of shielding noise.

  As shown in FIG. 9, a conventional shielded flat cable 50 includes a flat cable 52 in which a plurality of conductors 56, 56,... And a flat shield member 54 made of a metal foil such as copper foil or aluminum foil, and the flat shield member 54 is wound around the flat cable 52 in a “pile-wrap” shape (for example, a patent) Reference 1).

  As shown in FIG. 10A, the shielded flat cable 50 has a single bonded portion 54a of a flat shield member 54 formed on the upper surface. One conductor 56a of the flat cable 52 serves as a drain line. As shown in FIG. 10B, a part of the insulator 58 on the drain line 16a is peeled off (indicated by 58a). By exposing 16a and electrically connecting the shield member 54 and the drain line 16a, noise from the outside is shielded by the shield member 54 and dropped to the outside ground through the drain line 16a.

JP-A-8-7664

  However, since the conventional shielded flat cable 50 is obtained by winding a flat shield member 54 around the flat cable 52 in a “curly winding” shape, for example, a long flat cable used for a wire harness of an automobile or the like is used. There is a problem that it is difficult to wind the flat shield member 54. Further, since the shield member 54 is wound around the flat cable 52 after the flat cable 52 is cut into a predetermined length so that the shield member 54 can be easily wound, there is a problem that productivity is lowered.

  The problem to be solved by the present invention is to provide a shielded flat cable that facilitates shield processing of the flat cable and is excellent in productivity.

  In order to solve the above-mentioned problems, a shielded flat cable according to the present invention is covered with a flat cable in which a plurality of conductors spaced apart and arranged in parallel are covered with an insulator, and the outer periphery of the flat cable. The shield layer is formed by bonding a plurality of planar shield members together.

  In this case, the shield member can be shown as a preferred example having at least a conductive layer and an adhesive layer that partially covers the flat cable side surface of the conductive layer.

  Moreover, the said shield member can show as a suitable example what has an electroconductive layer and the contact bonding layer containing the electroconductive filler which coat | covers the surface by the side of the said flat cable of this electroconductive layer. .

  Preferably, at least one of the plurality of conductors is exposed from the insulator over the entire length on one side of the flat cable.

  In the shielded flat cable according to the present invention, the shield layer that covers the outer periphery of the flat cable is formed by laminating a plurality of planar shield members. For this reason, for example, a flat cable can be continuously shielded by supplying a plurality of flat shield members to both sides of the flat cable simultaneously with the production of the flat cable on a continuous production line. This makes it easy and improves productivity.

  Here, if the shield member has at least a conductive layer and an adhesive layer that partially covers the flat cable side surface of the conductive layer, a plurality of planar shield members are provided. These are easily conducted when they are bonded together.

  Similarly, if the shield member has at least a conductive layer and an adhesive layer containing a conductive filler covering the surface of the conductive layer on the flat cable side, a plurality of planar shapes are used. These are easily conducted when the shield members are bonded together.

  If at least one of the plurality of conductors is exposed from the insulator over the entire length on one side of the flat cable, the shield member includes a conductive layer and the flat of the conductive layer. When the shield member has at least an adhesive layer that partially covers the cable side surface, the shield member contains a conductive layer and a conductive filler that covers the flat cable side surface of the conductive layer. When at least one adhesive layer is provided, the conductive layer of the shield member is easily conducted over the entire length of at least one of the plurality of conductors, and welding for conduction can be omitted.

  Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view showing a shielded flat cable according to the first embodiment of the present invention, and FIG. 2 is an exploded perspective view of the shielded flat cable shown in FIG. FIG. 3 is a schematic diagram illustrating an embodiment of a shield member of a shielded flat cable. 4 is a cross-sectional view showing a shielded flat cable according to the second embodiment of the present invention, and FIG. 5 is an exploded perspective view of the shielded flat cable shown in FIG. FIG. 6 is a schematic diagram illustrating an example of a production line for a shielded flat cable. 7 and 8 are schematic views for explaining an example of the manufacturing process of the shielded flat cable. In the following description, the flat cable side in the shield member is referred to as the inner side.

  As shown in FIG. 2, in the shielded flat cable 10 according to the first embodiment of the present invention, a plurality of conductors 16, 16,... A flat cable 12 and a shield layer coated on the outer periphery of the flat cable 12. The shield layer is formed by bonding a plurality of planar shield members 14 and 14 together.

  In the flat cable 12, a plurality of rectangular conductors 16, 16,... Having a rectangular cross section are arranged in parallel and spaced apart from each other. The flat conductor 16 is made of a conductive metal such as copper or copper alloy, and one of the plurality of flat conductors 16, 16,... Is a drain wire 16a, and the remaining flat conductors 16,. Reference numerals 16,... Are signal lines. The plurality of flat conductors 16, 16,... Are covered with an insulator 18, and the plurality of flat conductors 16, 16,. The plurality of conductors 16, 16,... May be linear conductors, and are not particularly limited to flat conductors.

  The insulator 18 is composed of an insulating film in which an adhesive layer is formed on one side of an insulating layer made of an insulating synthetic resin, an insulating synthetic resin alone, or the like. As the insulating film, for example, an adhesive layer made of an adhesive having a melting property such as an olefin adhesive or a polyester adhesive is formed on one side of an insulating layer made of polyethylene terephthalate (PET) having good insulation. Can be exemplified. The thickness of the insulating film is preferably about 50 μm to 100 μm. The insulating synthetic resin itself is preferably a thermoplastic resin, and examples thereof include polyethylene, polyethylene terephthalate (PET), and polybutylene terephthalate (PBT).

  The flat cable 12 is formed by laminating a plurality of rectangular conductors 16, 16,... With an insulating film so that the two insulating films face each other with an adhesive layer, or a plurality of the above insulating synthetic resin alone. It is formed by extrusion coating on the rectangular conductors 16, 16,.

  As shown in FIG. 3A, the shield member 14 includes an insulating layer 20, a first adhesive layer 22, a conductive layer 24 made of a metal foil such as copper foil or aluminum foil, and a second adhesive layer 26. And has a four-layer structure laminated in this order. The first adhesive layer 22 adheres between the insulating layer 20 and the conductive layer 24, and the second adhesive layer 26 adheres the shield member 14 to the flat cable 12.

  The insulating layer 20 is preferably polyethylene terephthalate (PET) from the viewpoint of cost, but when flame retardancy or heat resistance is required, for example, polyphenylene sulfide (PPS), polyamideimide (PAI), polyetherimide, polyarylate Flame retardant engineering plastics such as polyimide (PI), polysulfone and polycarbonate (PC) are preferred.

  The first adhesive layer 22 and the second adhesive layer 26 only need to have adhesiveness, and for example, an adhesive resin having hot melt properties made of polystyrene, vinyl acetate, polyethylene, polypropylene, polyester, polyamide or the like. (Hot melt adhesive) is preferred. The first adhesive layer 22 is for bonding the conductive layer 24 and the insulating layer 20, and the second adhesive layer 26 is for bonding the shield member 14 to the outer periphery of the flat cable 12, The shield members 14 and 14 laminated on both surfaces of the flat cable 12 are attached to each other.

  The adhesive resin constituting the second adhesive layer 26 may contain a conductive filler such as a metal filler. Examples of the conductive filler include metal powders such as nickel, copper and silver, alloy powders such as solder, metal whiskers, glass fibers subjected to metal plating, and carbon powders, and adhesive resins thereof. The blending amount can be determined as appropriate. When the second adhesive layer 26 contains a conductive filler, the inner surface of the shield member 14 has conductivity due to the conductive filler.

  The second adhesive layer 26 is formed inside the conductive layer 24 so as to entirely or partially cover the inside of the conductive layer 24. As a form which partially covers the inner side of the conductive layer 24, for example, there is one shown in FIGS. These are views of the shield member 14 shown in FIG.

  In FIG. 3B, the second adhesive layer 26 is formed in a stripe shape inside the conductive layer 24. In this structure, a second adhesive layer 26 is formed in an oblique direction with an interval inside the conductive layer 24, and the conductive layer 24 is interposed between the second adhesive layer 26 and the second adhesive layer 26. Some are exposed.

  In FIG. 3C, the second adhesive layer 26 is formed in a spot shape inside the conductive layer 24. In this structure, the second adhesive layer 26 is arranged in an island shape inside the conductive layer 24, and a part of the conductive layer 24 is exposed as in the stripe shape of FIG. It has become.

  As shown in FIG. 3B, the stripe-shaped adhesive layer is not limited to the one in the oblique direction, and may be in the vertical and horizontal directions. Further, the spot-like adhesive layer is not limited to that shown in FIG. 3C, and may have various shapes such as a round shape and a triangular shape. Further, a net-like adhesive layer may be formed inside the conductive layer 24. In short, it is only necessary to partially cover the inner side of the conductive layer 24 and to have a conductive part and an adhesive part inside the shield member 14.

  In the case where the second adhesive layer 26 is formed inside the conductive layer 24 so as to partially cover the inside of the conductive layer 24, a part of the conductive layer 24 is exposed. The inner surface of the member 14 has conductivity.

  As shown in FIG. 1, the shielded flat cable 10 having the above-described configuration is a flat in which a plurality of flat rectangular conductors 16, 16,... Flat shield members 14 and 14 are bonded to both surfaces of the cable 12, and the flat shield members 14 and 14 are bonded to each other at the end of the flat cable 12. The bonding portion 14 a in the planar shield members 14, 14 is formed on the edge of the flat cable 12 in parallel with the surface of the flat cable 12.

  In the case where a flat shield member is wound around a flat cable in a conventional manner, the number of bonded portions of the shield member is one. However, in the flat cable 10 with a shield, the bonded portion Two 14a are formed.

  At this time, the shielded flat cable 10 needs to conduct the shield member 14 and the drain wire 16a in order to drop the noise shielded by the conductive layer 24 to the ground. Further, since a plurality of the planar shield members 14 are used, it is necessary to conduct them.

  In order to make the shield member 14 and the drain wire 16a conductive, the second adhesive layer 26 of the shield member 14 and the insulator 18 of the flat cable 12 are spot-connected or continuously by a method such as normal ultrasonic bonding. It is preferable to melt and melt the conductive layer 24 and the drain wire 16a in contact with each other. On the other hand, in order to conduct between the shield members 14 and 14 adhered to both surfaces of the flat cable 12, the welding is performed, and if the inner surface of the shield member 14 is conductive as described above, the shield is provided. When the members 14, 14 are bonded together, they are easily conducted.

  At this time, if the bonded portion 14a formed at the end portion of the flat cable 12 is folded back to one surface side of the shielded flat cable 10, the conduction is enhanced and the peeling between the shield members 14 and 14 is prevented. Also become.

  Next, a shielded flat cable 10 'according to a second embodiment of the present invention will be described.

  As shown in FIG. 5, the shielded flat cable 10 ′ according to the second embodiment of the present invention includes a plurality of conductors 16, 16,. The flat cable 12 is covered, and the shield layer is coated on the outer periphery of the flat cable 12. The shield layer is formed by bonding a plurality of planar shield members 14 and 14 together. In the flat cable 12, one conductor 16 a serving as a drain line among the plurality of conductors 16, 16,... Is exposed from the insulator 18 ′ over the entire length on one side of the flat cable 12. This is different from the first embodiment. Since the other structure of the flat cable 12 and the structure of the shield member 14 are the same as those of the first embodiment, the same reference numerals are given to the same structures, and redundant description is omitted.

  As shown in FIG. 4, the shielded flat cable 10 ′ having the above-described configuration is formed by covering a plurality of conductors 16, 16,. The flat shield members 14 and 14 are bonded to both surfaces of the flat cable 12, and the flat shield members 14 and 14 are bonded to each other at the end of the flat cable 12. Two bonding portions 14 a in the planar shield members 14, 14 are formed on the edge of the flat cable 12 in parallel with the surface of the flat cable 12. The drain wire 16a to be electrically connected to the conductive layer 24 is exposed over the entire length on one surface side of the flat cable 12, and the drain wire 16a and the shield member 14 are bonded to each other.

  At this time, as in the first embodiment, the shielded flat cable 10 ′ also conducts between the shield member 14 and the drain wire 16 a and between the shield members 14 and 14 laminated on both surfaces of the flat cable 12. There is a need.

  Here, in the shielded flat cable 10 ′, the drain wire 16 a to be electrically connected to the conductive layer 24 is exposed over the entire length on one side of the flat cable 12. If the second adhesive layer 26 is formed so as to partially cover the inside, or if the second adhesive layer 26 contains a conductive filler, the inner surface of the shield member 14 has conductivity. When the shield member 14 is affixed to the flat cable 12, the conductive layer 24 and the drain wire 16a are in direct contact with each other and are easily conducted. Further, when the shield members 14 are bonded to each other at the end portion of the flat cable 12, they are easily conducted. Therefore, since it is not necessary to perform the above welding in order to achieve conduction between them, the welding process can be omitted.

  As in the first embodiment, the bonded portion 14a between the shield members 14 and 14 formed at the end of the flat cable 12 may be folded back to one side of the shielded flat cable 10 '.

  Next, a method for manufacturing a shielded flat cable will be described. This production method is a production method using a continuous production line, and the flat cable is produced by a laminating method.

  First, the production line will be described. As shown in FIG. 6, the production line 30 includes a plurality of conductor supply rolls 34a, 34b, 34c,... As a conductor supply unit in which a linear rectangular conductor 16 is wound and accommodated upstream of a conveyance path 32. .. is disposed on the lower surface side of the conveying path 32, and an insulating film supply unit in which an insulating film 18 for laminating a plurality of rectangular conductors 16, 16,. The insulating film supply rolls 36a and 36b are arranged on the upper surface side and the lower surface side of the transport path 32, and the shield member 14 that covers the insulating film 18 and laminates them is wound and stored as a shield member supply unit. The shield member supply rolls 38 a and 38 b are arranged on the upper surface side and the lower surface side of the transport path 32.

  Further, on the downstream side of the transport path 32, heat rolls 40a and 40b for heating and pressurizing the shielded flat cable 10 in a stacked state are arranged on both upper and lower sides with the transport path 32 interposed therebetween. A winding roll 42 for winding the manufactured flat cable 10 with shield is arranged. The conductor supply rolls 34a, 34b, 34c,..., The insulating film supply rolls 36a, 36b, and the shield member supply rolls 38a, 38b guide the rectangular conductor 16, the insulating film 18, and the shield member 14 to the transport path 32, respectively. Guide rolls 44a, 44b, 44c,..., 46a, 46b, 48a, 48b are arranged.

  In this embodiment, an annealed copper wire having a thickness of 0.15 mm and a width of 1.5 mm is used as the flat conductor 16, and each of the conductors 16, 16,. 5 lines, 1 drain line). The insulating film 18 is configured such that an adhesive layer made of a polyester adhesive having a thickness of 40 μm is formed inside a polyethylene terephthalate (PET) film having a thickness of 50 μm. The shield member 14 includes, from the outside, an insulating layer 20 (polyphenylene sulfide (PPS), thickness 12 μm), a first adhesive layer 22 (polyester adhesive, thickness 20 μm), a conductive layer 24 (copper foil, thickness 9 μm), a second The adhesive layer 26 (Cu powder-containing polyester-based adhesive, thickness 20 μm) is laminated and bonded with a width of 9.9 mm. The configuration is not particularly limited to this.

  Next, a method for manufacturing the shielded flat cable 10 according to the first embodiment will be described with reference to FIGS.

  In the production line 30 shown in FIG. 6, when the rectangular conductors 16, 16,... Are supplied from the respective conductor supply rolls 34 a, 34 b, 34 c,. 16 are guided by guide rolls 44a, 44b, 44c,... And are arranged parallel to each other in the transport path 32, resulting in the state of FIG. Next, the plurality of flat conductors 16, 16,... Arranged in parallel are further transported along the transport path 32. When the insulating films 18 and 18 are supplied from the upper and lower directions from the insulating film supply rolls 36a and 36b in the middle of the transport path 32, the insulating films 18 and 18 guided by the guide rolls 46a and 46b are plurally arranged in parallel. The flat conductors 16, 16,... Are slightly wider than both ends of the flat conductors 16, 16,. Next, when the shield members 14 and 14 are supplied from the upper and lower directions from the shield member supply rolls 38a and 38b, the shield members 14 and 14 are provided on both outer sides of the insulating films 18 and 18 that are guided and laminated by the guide rolls 48a and 48b. Is wider than the insulating film 18 and is in the state of FIG.

  Next, each of the components in the laminated state is further transported through the transport path 32, and when heated and pressurized downstream of the transport path 32 by, for example, heat rolls 40a and 40b heated to 140 ° C., the insulating film 18 Both shield members in which the adhesive layer is melted and the insulating films 18 and 18 and between the insulating film 18 and the flat conductor 16 are adhered, and the second adhesive layer 26 of the shield member 14 is melted and laminated. 14, 14 and between the shield member 14 and the insulating film 18 are adhered, and the shielded flat cable 10 in the state of FIG. 7D is completed. The bonded portion 14 a in the laminated planar shield members 14, 14 is formed on the edge of the flat cable 12 in parallel with the surface of the flat cable 12.

  At this time, if the inner surface of the shield member 14 has conductivity, the laminated shield members 14 and 14 are bonded to each other by heating and pressurization by the heat rolls 40a and 40b, and at the same time, they are full length. Conducted.

  The shielded flat cable 10 obtained as described above is wound around the winding roll 42 downstream of the heat rolls 40a and 40b in a long state.

  Next, a manufacturing method of the shielded flat cable 10 ′ according to the second embodiment will be described. This shielded flat cable 10 ′ is a flat cable 10 with shield according to the first embodiment in that a drain line 16 a to be electrically connected to the conductive layer 24 is exposed over the entire length on one side of the flat cable 12. And the configuration is different. Therefore, it is supplied from each conductor supply roll 34a, 34b, 34c... Upstream of the transport path 32, and on both surfaces of a plurality of flat conductors 16, 16,... (FIG. 8A) arranged in parallel. When laminating the insulating film, as shown in FIG. 8B, an insulating film 18 'with a reduced width is provided on the upper side of the flat conductors 16, 16,. The flat rectangular conductor 16a is supplied so as to be exposed over the entire length on the upper surface. On the other hand, below the flat conductors 16, 16,..., An insulating film 18 'is supplied that is slightly wider than both end positions of the parallel flat conductors 16, 16,.

  Next, when the shield member 14 is supplied from the upper and lower directions from the shield member supply rolls 38a and 38b, the shield members 14 and 14 are wider than the insulating film 18 'and laminated on both outer sides of the laminated insulating films 18' and 18 '. Then, the state shown in FIG. When heated and pressed by the heat rolls 40a and 40b in this state, the adhesive layer of the insulating film 18 'is melted so that both the insulating films 18' and 18 'and between the insulating film 18' and the flat conductor 16 are connected. At the same time, the second adhesive layer 26 of the shield member 14 is melted and laminated, and between the shield members 14 and 14 and between the shield member 14 and the insulating film 18 '.

  At this time, since the upper surface of the endmost rectangular conductor 16a serving as the drain line is not covered with the insulating film 18 ', the second adhesive layer 26 of the shield member 14 extends over the entire length of the endmost rectangular conductor 16a. Glued directly across. If the inner surface of the shield member 14 has conductivity, the laminated shield members 14 and 14 are bonded to each other by heating and pressurization by the heat rolls 40a and 40b, and at the same time, are conducted over the entire length. Is done. Further, the shield member 14 and the drain wire 16a are electrically connected over the entire length.

  The shielded flat cable 10 ′ in the state of FIG. 8D is completed, and is wound around the winding roll 42 downstream of the heat rolls 40 a and 40 b in a long state.

  According to the shielded flat cable 10 configured as described above, a plurality of planar shields are formed on both sides of the flat cable 12 simultaneously with the production of the flat cable 12 on the production line 30 as described in the above production method. Since the flat cable 12 can be continuously shielded by supplying the members 14 and 14, the shield processing of the flat cable 12 is facilitated and the productivity is excellent.

  Further, according to the shielded flat cable 10 ′, the drain line 16 a is exposed over the entire length on one side of the flat cable 12, and the drain line 16 a is electrically connected to the conductive layer 24 of the shield member 14 over the entire length. So it has excellent shielding performance.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the present invention.

  For example, in the above-described embodiment, the insulator 18 of the flat cable 12 may be made of a single insulating synthetic resin, and the plurality of conductors 16, 16,. Further, the bonding portion 14 a in the flat shield members 14 and 14 bonded to both surfaces of the flat cable 12 is limited to those formed on the edge of the flat cable 12 in parallel with the surface of the flat cable 12. For example, at the edge of the flat cable 12, a flat shield member bonded to the lower (upper) surface on the flat shield member 14 bonded to the upper (lower) surface. 14 may be overlapped. Of course, the planar shield member 14 bonded to both surfaces of the flat cable 12 may be three or more.

  The shielded flat cable according to the present invention is suitably used for wiring of electrical components mounted on OA equipment, home appliances, vehicles such as automobiles, and the like.

It is sectional drawing showing the flat cable with a shield which concerns on 1st embodiment of this invention. It is a disassembled perspective view of the flat cable with a shield which concerns on one Embodiment of this invention. It is a schematic diagram showing one Embodiment of the shield member of the flat cable with a shield. It is sectional drawing showing the flat cable with a shield which concerns on 2nd embodiment of this invention. It is a disassembled perspective view of the flat cable with a shield which concerns on two embodiment of this invention. It is the schematic which shows an example of the manufacturing line of a flat cable with a shield. It is a schematic diagram explaining an example of the manufacturing process of a flat cable with a shield. It is a schematic diagram explaining an example of the manufacturing process of a flat cable with a shield. It is a schematic diagram showing an example of a structure of the conventional flat cable with a shield. It is a schematic diagram showing an example of a structure of the conventional flat cable with a shield.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Flat cable with shield 12 Flat cable 14 Shield member 16 Conductor 16a Drain wire 18 Insulator 26 Second adhesive layer

Claims (4)

A flat cable in which a plurality of conductors that are spaced apart from each other and are arranged in parallel are covered with an insulator, and a shield layer that is covered on the outer periphery of the flat cable;
The shielded flat cable is characterized in that the shield layer is formed by bonding a plurality of planar shield members.   The shielded flat cable according to claim 1, wherein the shield member includes at least a conductive layer and an adhesive layer that partially covers a surface of the conductive layer on the flat cable side.   The said shield member has at least the conductive layer and the contact bonding layer containing the conductive filler which coat | covers the surface by the side of the said flat cable of this conductive layer, The Claim 1 or 2 characterized by the above-mentioned. Shielded flat cable.   4. The shielded flat according to claim 1, wherein at least one of the plurality of conductors is exposed from the insulator over the entire length on one side of the flat cable. 5. cable.

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