JPH0626119U - Insulated wire and coaxial cable - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an insulated electric wire having excellent cut-through resistance, dimensional stability, flexibility and light weight, and having easy workability. To provide a coaxial cable in which excellent transmission characteristics are stably maintained. To provide insulated wires and coaxial cables suitable for high temperatures. [Structure] A heat-resistant insulating layer 3 and a tape winding layer 4 made of an extremely thin polyether ether ketone resin tape are sequentially provided around a conductor 2, and the tape winding layer 4 is melted and integrated. Insulated wire 1. Further, a coaxial cable in which the insulated wire 1 is a core and an outer conductor layer is provided on the outer periphery thereof is also included.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an insulated electric wire using a double coating layer composed of a heat resistant insulating layer and a polyetheretherketone resin (hereinafter referred to as PEEK), and a coaxial cable using the insulated electric wire as a core (coaxial core). .

[0002]

[Prior art]

 Since PEEK has high mechanical strength and excellent properties such as heat resistance, it has been used for coating insulated wires. For example, PEEK has been conventionally used for the purpose of improving extrudability. As described in Japanese Patent Laid-Open No. 2-27611 in which PEEK is double extruded, a heat-resistant insulating layer is provided around a conductor, and PEEK is melt-extruded and coated thereon to form a two-layer structure. Insulated wires having the above insulation coating have been proposed. This is because even if the PEEK coating layer is cracked or cracked due to bending or the like, the heat-resistant insulating layer maintains its insulating property, and dielectric breakdown is prevented under high voltage. As the material for the heat resistant insulating layer, for example, polyimide resin, aromatic polyamide resin, PEEK or the like is used.

Further, a low dielectric constant obtained by a method such as a foamed fluororesin layer extruded on an insulator of an insulated wire or a dielectric of a core of a coaxial cable, or a method of generally stretching by winding a tape. , A porous porous tetrafluoroethylene resin (hereinafter referred to as EPTFE) layer having a small dielectric loss tangent is used. However, since such a foamed fluororesin layer or EPTFE layer is easily deformed and easily crushed, when the foamed fluororesin layer or EPTFE layer is crushed, the dielectric constant increases and the transmission characteristics become unstable. Due to problems, it is necessary to provide a reinforcing layer around the foamed fluororesin layer and the EPTFE layer for preventing crushing without impairing the electrical characteristics. Therefore, conventionally, a tape material in which a hot melt paste such as vinyl chloride is applied to a polyester tape is wrapped around the EPTF E layer, and a reinforcing layer having a structure in which the hot melt paste is melted and integrated is used. It was being appreciated.

[0004]

[Problems to be solved by the device]

 However, the above-mentioned conventional insulated wire or coaxial cable has problems as described in (a) to (C). Since (a) PEEK is extrusion-coated, it is difficult to obtain an extremely thin coating having sufficient cut-through resistance due to extrusion restrictions such as eccentricity. Therefore, it is difficult to be flexible, lightweight, and processable, so it is only used in small amounts for special purposes. (b) Even if an EPTFE layer with a low dielectric constant and a small dielectric loss tangent is used, the reinforcing layer around it is a material with poor electrical characteristics and it is necessary to make it relatively thick to prevent crushing. The characteristics were deteriorated. (c) Since the heat resistance of the reinforcing layer depends on the melting point of the hot melt paste, the operating temperature limit is usually about 100 ° C., and an insulated wire or coaxial cable for high temperature cannot be obtained.

In view of this prior art, the present invention has an extremely thin coating having sufficient cut-through resistance, is excellent in heat resistance, and is excellent in flexibility and light weight, and facilitates workability. It is an object to provide an insulated wire and a coaxial cable. Another object is to provide an insulated wire and a coaxial cable in which excellent transmission characteristics are stably maintained. This coaxial cable includes a semi-rigid cable.

[0006]

[Means for Solving the Problems]

 The present invention has been made in order to achieve the above-mentioned object, and in this insulated wire, a heat-resistant insulating layer and a tape winding layer made of an ultrathin PEEK tape are sequentially provided around a conductor. Is characterized by being melted and integrated. In a coaxial cable, a heat-resistant insulating layer and a tape winding layer made of ultra-thin PEE K tape are sequentially provided around a conductor, and the core is formed by melting and integrating the tape winding layer. And an outer conductor layer provided on the outer periphery of the.

[0007]

[Action]

 According to the present invention, the insulated wire is provided with a tape winding layer made of ultra-thin PEEK tape around the heat-resistant insulating layer, and the tape winding layer is melt-integrated, so that the cut-through resistant It is possible to obtain a coating layer having excellent properties, lightness, and workability, and having a uniform thickness. From this, the flexibility of the heat resistant insulating layer is hardly impaired, and an insulated wire and a coaxial cable having excellent flexibility can be obtained. Further, although the PEEK covering layer is extremely thin, it is dimensionally stable and has sufficient strength.

Further, in this insulated wire and coaxial cable, since the PEEK coating layer is present as the outermost layer, mechanical strength is high, and external damage resistance, abrasion resistance, heat resistance, solder resistance, low smoke generation, It has properties such as flame resistance, heat aging resistance, heat shrinkage resistance, low temperature resistance, water resistance, chemical resistance, radiation resistance, and light weight. The insulated electric wire is used alone, and is also used as a core of, for example, 2 to 4 twisted electric wires, multi-core twisted cables, coaxial cables and the like.

For example, when forming a coaxial cable, the heat-resistant insulating layer is an EPTFE layer, and an ultrathin PEEK coating layer is provided around the EPTFE layer to protect the PE EK coating layer from the EPTFE layer. It becomes a layer, and the collapse of the EPTFE layer is prevented. This PEEK has a low relative permittivity of about 3.1 and a dielectric loss tangent of about 0.47%, and therefore has sufficiently excellent electrical characteristics as compared with conventional reinforcing layer materials. Moreover, since the PEEK coating layer is extremely thin, the electrical characteristics of the EPTFE layer are less affected. In addition, even if it is extremely thin, it has high mechanical strength, so it is more effective than conventional reinforcement layers in crush prevention and cut-through resistance. Therefore, it is possible to obtain excellent transmission characteristics such that the low dielectric constant is maintained and the propagation delay time is shortened.

[0010]

【Example】

 Hereinafter, an embodiment of an insulated wire and a coaxial cable according to the present invention will be described with reference to the drawings. First, FIG. 1 is a cross-sectional view showing an embodiment of an insulated wire according to the present invention. Here, referring to FIG. 1, the insulated wire 1 is formed by extending from the front to the back in the figure, and is composed of a heat-resistant insulating layer 3 and an ultrathin PEEK tape around a conductor 2. The tape winding layer 4 is sequentially provided, and the tape winding layer 4 is melted and integrated.

Further, the insulated electric wire 1 includes a tape winding layer made of, for example, an EPTFE tape having a thickness of about 80 μm around the conductor 2 of AWG 34, which is formed by twisting seven wires each having a diameter of 0.064 mm. Is wound to form a heat-resistant insulating layer 3, and a PEEK tape having a thickness of about 7 μm is overlapped with the tape winding layer 4 by 50%, and the heat-resistant insulating layer 3 is made of the EPTFE tape winding layer. Does not shrink or shrinks slightly (in this embodiment, at 380 ° C. for about 45 seconds), the tape winding layer 4 is melted and integrated at a temperature higher than the melting point of PEEK (334 ° C.). You can The PEEK tape can withstand the tension required for winding the tape if the thickness is about 7 μm as described above. Further, this ultra-thin PEEK tape preferably has a thickness of at least about 25 μm or less in consideration of flexibility and workability. This insulated electric wire 1 is excellent in flexibility, light weight, etc. and is easily processed by forming a thin PE EK coating.

[0012] Furthermore, the cut-through characteristics of five samples of the above-mentioned insulated wire 1 (outer diameter 0.5 mm) were measured by a dynamic load cut-through tester with a cutting edge radius of 0.03 mm and a cutting edge angle of 90 °. The conductor and the cutting edge did not short-circuit (cut through) up to 5 kgf, which is the upper limit of the tester. On the other hand, the same test was performed on an insulated wire having the same structure as the insulated wire 1 except that a polyester tape coated with vinyl chloride hot melt adhesive on one side was used instead of the above-mentioned ultrathin PEEK tape. The cut-through load was 2 kgf or less. Therefore, the insulated wire according to the present invention has extremely high cut-through characteristics. Further, the insulated electric wire 1 does not need to use a hot-melt adhesive having a low heat resistance as in the conventional case in order to integrate the insulating coating layer, and as a result, has a high heat resistance.

In addition, in order to apply the structure of the present invention to an aircraft electric wire, an EPTFE tape is wound around the outer periphery of the AWG26 conductor, which is formed by twisting 19 copper alloy wires having a diameter of 0.102 mm, and around the periphery of the conductor. An insulated electric wire having an outer diameter of 0.686 mm and a rating of 600 V and 200 ° C. was formed by winding a PEEK tape having a thickness of about 7 μm and melting and integrating the PEEK tape. The weight of this insulated wire is 1. It was 930 kg / 1000 m. On the other hand, the two-layer cross-linked XL-ETFE electric wire of MIL-W-22759 / 41 -26 which is the MIL standard electric wire with the same rating has an outer diameter of 1.016 mm and a weight of 2.530 kg / 1000 m. In addition, the insulated wire with two layers of fluorocarbon / polyimide tape of MIL-W-81381 / 7-22 of the same rating and coated with polyimide has a weight of 1.935 kg / 1000 m, but an outer diameter of 0.864 mm. In addition, it is extremely less flexible than the insulated wire of the present invention. Therefore, the insulated wire of the present invention is superior to the insulated wire of the same rating in terms of lightness, thinness, flexibility, cut resistance, and heat resistance, and is thus suitable as an aircraft wire.

FIG. 2 is a cross-sectional view showing an embodiment of the coaxial cable according to the present invention. Referring to FIG. 2, the coaxial cable 5 uses the insulated wire 1 described in FIG. 1 as the core 6. That is, the core 6 is obtained by sequentially providing a heat-resistant insulating layer 3 made of EPTF E and a tape winding layer 4 made of an ultrathin PEEK tape around the conductor 2, and melting and integrating the tape winding layer 4. An outer conductor layer 7 is provided around the outer conductor layer, and a jacket layer 8 is provided as necessary to form a coaxial cable 5. The outer conductor layer 7 is, for example, a braided or horizontally wound conductive linear body such as metal, a conductive foil-shaped body spirally or cylindrically wound, or a conductive tubular body. Is used.

As the coaxial cable 5, an AWG34 No. 34 silver-plated conductor with a diameter of 0.192 mm, in which seven strands with a diameter of 0.064 mm are twisted, is used to actually reduce the dielectric constant to an extremely low thickness. A heat-resistant insulating layer consisting of a wound EPTFE tape of about 80 μm is provided to have an outer diameter of 0.5 mm, and a tape winding layer of an ultra-thin PE EK tape of about 7 μm thickness is provided around this heat-resistant insulating layer. , The tape wound layer was melted and integrated to have an outer diameter of 0. A semi-rigid coaxial cable with a dielectric outer diameter of 0.35 mm was made by using a 53 mm core and covering the outer circumference with a 0.08 mm thick copper pipe (external conductor layer) and pulling it down. When the propagation delay time Tpd of this semi-rigid coaxial cable is measured, 3. It was 84 nanoseconds / m. This is extremely superior to conventional coaxial cables. Further, when calculated from the value of the propagation delay time Tpd, the composite relative permittivity εr of the heat resistant insulating layer and the tape winding layer was 1.33. The capacitance of this cable was 72 pF / m.

It should be noted that the present invention is not limited to the above-described embodiment, and for example, another conventional heat resistant insulating layer is used as the heat resistant insulating layer, a tape having a different thickness is used, or a PEEK tape is used. Various modifications are naturally possible within the technical concept of the present invention, such as different overlapping ratios and two or more PEEK tapes.

[0017]

[Effect of device]

 As explained above, the insulated wire of the present invention has high mechanical strength, and is resistant to external damage, cut-through resistance, abrasion resistance, heat resistance, solder resistance, flame retardancy, heat aging resistance, and heat shrinkage. In addition to having the following properties: low temperature resistance, low temperature resistance, water resistance, chemical resistance, radiation resistance, low smoke generation, and light weight, the PEEK coating layer is extremely thin, resulting in excellent flexibility and processability. . In addition, a coaxial cable that uses this insulated wire as a core and has a heat-resistant insulating layer as EPTFE prevents crushing, so that the low dielectric constant of the insulating coating (dielectric) is maintained and the conventional coaxial cable is used. This has the effect of reducing the signal propagation delay time and stabilizing the transmission characteristics. Further, the insulated wire and the coaxial cable according to the present invention have high heat resistance.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of an insulated wire according to the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of a coaxial cable according to the present invention.

[Explanation of symbols]

 1 Insulated wire 2 Conductor 3 Heat resistant insulating layer 4 Tape winding layer made of ultra-thin PEEK tape 5 Coaxial cable 6 Core 7 Outer conductor layer 8 Jacket layer

Claims (2)

[Scope of utility model registration request] 1. A heat-resistant insulating layer and a tape winding layer made of an extremely thin polyetheretherketone resin tape are sequentially provided around a conductor, and the tape winding layer is melted and integrated. Insulated wire. 2. A core comprising a heat-resistant insulating layer and a tape winding layer made of an extremely thin polyetheretherketone resin tape, which are sequentially provided around a conductor, and the tape winding layer is melt-integrated. A coaxial cable comprising an outer conductor layer provided on the outer periphery of a core.