SHIELD WIRE

Abstract

A shield wire is formed of eight twisted insulated core wires 1, an inclusion 2 between these respective insulated core wires 1, a tape 3 laterally wound around an outer periphery of a core formed of the insulated core wires and inclusion, a drain wire 4 disposed on an outer surface of the tape, a conductive fiber braided body 5 formed on an outer peripheral surface of the tape so as to interpose the drain wire, a sheath 6 that forms an outer peripheral surface of the braided body, and an adhesive layer 7 between the braided body and sheath. A braided body 5′ is adhesively integrated to the sheath 6′ by an adhesive layer; thus, the braided body 5′ is stripped with the sheath. This eliminates a need for a removal work of the braided body after stripping the sheath, thus ensuring good workability of the terminal processing.

Claims

1. A shield wire (P) comprising: a plurality of insulated core wires (1) twisted to form a core (1′), a conductive fiber braided body (5) formed on an outer periphery of the core (1′), and a sheath (6) disposed outside the conductive fiber braided body (5), wherein an adhesive layer (7) is interposed between the conductive fiber braided body (5) and the sheath (6), the adhesive layer (7) adheres the conductive fiber braided body (5) to the sheath (6), and the adhesive layer (7) is disposed on a whole surface of an outer periphery of the conductive fiber braided body (5) by extrusion molding of a thermoplastic adhesive resin.

2. The shield wire according to claim 1, wherein between the core (1′) of the twisted insulated core wires (1) and the conductive fiber braided body (5), a drain wire (4) is disposed to be electrically coupled to the conductive fiber braided body (5).

3. (canceled)

4. The shield wire according to claim 1, wherein the conductive fiber braided body (5) is made of a resin-coated conductive fiber.

5. The shield wire according to claim 4, wherein the coating resin is a thermoplastic adhesive resin.

6. The shield wire according to claim 1, wherein a cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

7. The shield wire according to claim 2, wherein the conductive fiber braided body (5) is made of a resin-coated conductive fiber.

8. The shield wire according to claim 7, wherein the coating resin is a thermoplastic adhesive resin.

9. The shield wire according to claim 2, wherein the cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

10. The shield wire according to claim 4, wherein a cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

11. The shield wire according to claim 5, wherein a cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

12. The shield wire according to claim 7, wherein a cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

13. The shield wire according to claim 8, wherein a cross-sectional surface of the core (1′) is formed into a circular shape by twisting the insulated core wires (1) with an inclusion (2).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 is a cross-sectional view of one embodiment of a shield wire according to the present invention.

[0032] FIG. 2 is a front view of a main part partially cut of the embodiment.

[0033] FIG. 3 is a perspective view for describing terminal processing of the embodiment.

DESCRIPTION OF THE EMBODIMENTS

[0034] FIG. 1 and FIG. 2 illustrate one embodiment of a shield wire P according to the present invention. This shield wire P is for a robot cable. The shield wire P is formed of eight twisted insulated core wires 1, an inclusion 2 between these respective insulated core wires 1, a tape 3 laterally wound around an outer periphery of a core 1′ formed of these insulated core wires 1 and inclusion 2, a drain wire 4, which is over a whole wire length, disposed on an outer surface of the tape 3, a conductive fiber braided body 5 formed on an outer peripheral surface of the press tape 3 so as to interpose the drain wire 4, a sheath (a protecting layer) 6 that forms an outer peripheral surface of the braided body 5, and an adhesive layer 7 between the braided body 5 and sheath 6.

[0035] The insulated core wire 1 has an insulating coating 1b, which is polyvinyl chloride or the like, disposed on a copper alloy twisted wire 1a whose cross-sectional area is 0.2 mm.sup.2. The number, an outside diameter, and the like of this insulated core wire 1 can be appropriately set corresponding to a usage aspect. According to this embodiment, the insulating coating 1b is made of polyvinyl chloride. The insulating coatings 1b of the respective insulated core wires 1 may have appropriately different colors such as red, green, black, or white to ensure identification.

[0036] The inclusion 2 is made of cotton yarn. The inclusion 2 is used for roundly finishing the core 1′ when twisting the respective insulated core wires 1. Well-known material such as PPC yarn other than the cotton yarn can appropriately employed. The insulated core wires 1 are twisted via this inclusion 2. Therefore, this core 1′ has a cross-sectional circular shape, as illustrated in FIG. 1.

[0037] The tape 3 is formed of a paper tape or a plastic tape. The tape 3 is vertically attached or laterally wound in order to maintain a cross-sectional circular shape of the core 1′ formed of the insulated core wires 1 and the inclusion 2. In this embodiment, the tape 3 is laterally wound (wound around).

[0038] The drain wire 4 is formed of a copper alloy twisted wires whose cross-sectional area is 0.2 mm.sup.2. The drain wire 4 is vertically attached or laterally wound. In this embodiment, one drain wire is laterally wound. The number of the drain wire 4 can be arbitrarily set.

[0039] The conductive fiber braided body 5 is made of carbon fiber, or copper-plating polyester fiber or the like. In this embodiment, both carbon fiber and copper-plating polyester fiber are separately used (different shield wires are made). Using the respective fibers, braid is performed with 100% of braid density.

[0040] The sheath 6 is made of well-known resin such as polyvinyl chloride, polyethylene, polyurethane, or polyester. In this embodiment, polyvinyl chloride is employed.

[0041] As the adhesive layer 7, resin having high adhesive property with respect to the braided body 5 and the sheath 6 can be appropriately employed. In this embodiment, polyester-based thermoplastic adhesive resin is used. The adhesive layer 7 may be formed of thermoplastic adhesive resin of polystyrene-based, vinyl acetate-based, polyethylene-based, polypropylene-based, polyamide-based, rubber-based, acrylic-based, or the like. Add-in material such as metal powders, carbon black, filler, or stiffener may be added to the adhesive layer 7. However, if these add-in materials are added more than a specific amount, the add-in materials may easily expose from a surface of the adhesive layer so that the satisfactory adhesive property to the sheath 6 may not be guaranteed. Therefore, when adding these add-in materials, amounts of these add-in materials are appropriately chosen considering the adhesive property.

[0042] The shield wire P in this embodiment has the above-mentioned configuration. For fabrication of the shield wire P, first, the insulated core wires 1 and the inclusion 2 are sent into a twisting machine to be twisted. The tape 3 is laterally wound around this twisted core 1′. Therewith, the drain wire 4 is laterally wound over the whole length of the wire. Furthermore, on this, the conductive fiber braided body 5 is formed using a braiding machine.

[0043] Next, the adhesive resin is extruded to form the adhesive layer 7 on a whole surface of the outer periphery of the core 1′ on which this conductive fiber braided body 5 is formed, by an extruder. Furthermore, on this, the sheath 6 is disposed by the extrusion molding of the resin using the extruder. In this manner, the shield wire P according to the present invention is fabricated.

[0044] Such fabricated shield wire P can be used as robot cable for communication, for electric power, or the like. When receiving the bending action in accordance with the movement of a robot, the shield wire P has a configuration that is less likely to break at the braided body 5 and is excellent in the bending resistance because the braided body 5 adheres to the sheath 6 so as to be integrated, compared with the above-described conventional shield wire using a braided body.

[0045] In terminal processing of this shield wire P, first, as illustrated in FIG. 3, a nick t is made over a whole circumference of the sheath 6 at a necessary length part of the terminal by scissors or a stripper. This nick t is also made at the braided body 5 to the extent that the drain wire 4 is not cut (the nick t is not made at the drain wire 4). In this case, the core 1′ is formed so as to have the cross-sectional circular shape, and furthermore, the extrusion molding of the adhesive resin forms the adhesive layer 7 on the whole surface of the outer periphery of the core 1′. Therefore, a braided body 5′ of this terminal is certainly adhered (integrated) to a whole surface of an inner periphery of a sheath 6′ by the adhesive layer 7. Therefore, the nick t can be easily made at the braided body 5′, as well as the sheath 6′.

[0046] Next, under the state where the nick t is made, using the stripper or the like, the sheath 6′ of the terminal is moved as the arrow in the Figure. Then, the braided body 5′, as well as the sheath 6′, is certainly stripped via the nick t. Then, the core 1′ of the insulated core wires 1 around which the tape 3 is wound and the drain wire 4 is laterally wound is exposed (from a chain-line state to a solid-line state in FIG. 3).

[0047] Afterward, like the conventional one, the press tape 3 and the drain wire 4 are removed from the core 1′ of the insulated core wires 1. Then, after finishing stripping the insulating coatings 1b of the insulated core wires 1, and the like, the insulated core wires 1 and the drain wire 4 are coupled to end terminals of various connectors and electrical devices.

[0048] At the shield wire P in the above-described embodiment, the above-described conductive fiber braided body 5 may be formed of resin-coated fiber.

[0049] Insofar as the coating resin is the thermoplastic adhesive resin, in the extrusion molding of the sheath 6, heat of the sheath 6 by extrusion molding melts the adhesive resin to adhere the sheath 6 to the braided body 5 and ensure forming the above-described adhesive layer 7. Accordingly, a formation process of the adhesive layer 7 by the above-described extrusion molding of the adhesive resin can be omitted. As the coating resin, resin having the high adhesive property with respect to the sheath 6 can be appropriately employed. For example, similar to the above-described one, the polyester system thermoplastic adhesive resin or the like can be employed.

[0050] For the conductor 1a of the above-described insulated core wire 1 and the drain wire 4, twisted wires or single wires of the above-described copper alloy wires can be employed.

[0051] On the other hand, the drain wire 4 can be omitted. In this aspect, the conductive fiber braided body 5 is used in order to be earthed. Specifically, when stripping the above-described braided body 5, one part of this braided body 5 is not stripped to be left. Then, for example, means that using the left braided body 5 to couple to a grounding terminal of the electrical device or the like can be employed. Describing the procedure in more detail, when the nick t is made at outer peripheries of the sheath 6 and the braided body 5 by the scissors or the like, the nick t is made over the whole outer periphery for the sheath 6. For the braided body 5, the nick t is made so as to leave a portion at which the nick t is not made at a part of the outer periphery. In this state, the necessary length of sheath 6′ is stripped from the terminal. In this stripping, the sheath 6′ is slowly stripped so as not to simultaneously strip the braided body 5 at the portion at which the nick t is not made. In this way, the part of the braided body 5 does not follow the sheath 6′ and is left at a side of a product (a wire main body). Therefore, this left braided body 5 is coupled to the grounding terminal or the like of the electrical device or the like.

[0052] The tape 3 also can be omitted as long as it may not influence the twisting of the insulated core wires 1. At this time, the respective insulated core wires 1 are twisted with the inclusion 2. Then, the twisted core 1′ is formed so as to have the cross-sectional circular shape roundly finished.

[0053] Furthermore, it is obvious that the shield wire P according to the present invention can be used for not only the robot cable, but also various cables or the like that request the bending resistance.

[0054] This application claims priority from Japanese Patent Application No. 2014-164408 filed with the Japanese Patent Office on Aug. 12, 2014, the entire contents of which are hereby incorporated by reference.

[0055] The above-disclosed embodiment is all considered as illustrative and not restrictive. The scope of the invention is indicated by the appended claims. All variations and equivalents which fall within the range of the appended claims are intended to be embraced therein.

LIST OF REFERENCE NUMERALS

[0056] P: Shield wire [0057] t: Nicks of sheath and braided body [0058] 1: Insulated core wire [0059] 1a: Conductor of insulated core wire [0060] 1b: Insulating coating of insulated core wire [0061] 1′: Core of twisted insulated core wires [0062] 2: Inclusion [0063] 3: Tape [0064] 4: Drain wire [0065] 5: Conductive fiber braided body [0066] 5′: Stripped terminal braided body [0067] 6: Sheath (Protecting layer) [0068] 6′: Stripped terminal sheath [0069] 7: Adhesive layer