Patent Description:
PTL <NUM> discloses an electronic wire conductor for an automobile having a cross-sectional area of <NUM> to <NUM><NUM> by combining sub-conductors formed of copper or copper alloy having a <NUM>% proof stress of <NUM> to <NUM>/mm<NUM>, and the conductivity of <NUM>% IASC or more. <CIT> relates to an insulated electric wire. <CIT> relates to an electrical cable. <CIT> relates to an aluminum electric wire for an automobile and a method for producing the same. <CIT> relates to a core wire for multi-core cables and a multi-core cable.

An electronic wire according to an aspect of the present disclosure is according to claim <NUM>.

A cable according to the current invention includes.

The electronic wire conductor for an automobile disclosed in PTL <NUM> is intended to reduce the weight of the electronic wire, and has improved reliability with respect to repeated bending. For example, for electronic wires and cables used in automobiles, a further reduction in the diameter of the electronic wires is desired, and the electronic wires and cables excellent in bending resistance notwithstanding the reduced diameter are preferable.

Therefore, an objective of the present disclosure is to provide an electronic wire and a cable, which is excellent in bending resistance even when the diameter is small.

According to the present disclosure, it is possible to provide an electronic wire and a cable which are excellent in bending resistance even when the diameter is small.

First, embodiments of the present invention will be listed and described.

An electronic wire according to an aspect of the present invention is.

The electronic wire having the configuration described above has a good balance between tensile strength and breaking elongation, and therefore has excellent bending resistance even when the diameter is small.

A cable according to the present invention includes.

The cable having the configuration described above has a good balance between tensile strength and breaking elongation, and therefore has excellent bending resistance even when the diameter is small.

Specific examples of an electronic wire and a cable according to embodiments of the present invention will be described below with reference to the drawings.

In addition, the present invention is not limited to these embodiments, but is intended to be indicated by the claims.

<FIG> shows an example of an electronic wire. The electronic wire <NUM> is used as a power supply line or a signal line for transmitting electric power to a motor or the like.

As shown in <FIG>, the electronic wire <NUM> includes a conductor <NUM> and an insulating layer <NUM> provided on the outer peripheral side of the conductor <NUM>.

The conductor <NUM> is formed of a plurality of (seven, in this example) small-diameter conductors <NUM>. These small-diameter conductors <NUM> all have the same structure. Each of the small-diameter conductors <NUM> is formed as a twisted wire in which a plurality of wires formed of an annealed copper wire are twisted together, for example. The conductor <NUM> is formed as a double twisted wire in which seven small-diameter conductors <NUM> (twisted wires) are further twisted.

The diameter of a wire is <NUM> or more and <NUM> or less. The number of wires forming one small-diameter conductor <NUM> is about <NUM> to <NUM>, for example.

The cross-sectional area of the conductor <NUM> is <NUM><NUM> or more and <NUM><NUM> or less.

For a material of the wire forming the conductor <NUM>, a copper alloy wire may be used in addition to the copper wire described above, for example. A conductor having a breaking elongation of <NUM>% or more and <NUM>% or less and a tensile strength of <NUM> MPa or more and <NUM> MPa or less has a smaller breaking elongation and a higher tensile strength than a normal annealed copper wire. In order to obtain such a conductor, when manufacturing the copper for forming the conductor by annealing, the heat applied to the copper is desirably lower than when manufacturing soft copper.

In the present embodiment, the conductor is formed by using a wire that is annealed under the condition of heating at a temperature of <NUM> to <NUM>, for <NUM> to <NUM> seconds. The conductor <NUM> is formed such that the elongation until the conductor <NUM> is broken (breaking elongation) is <NUM>% or more and <NUM>% or less, and is formed such that the force (tensile strength) against the tension when the conductor <NUM> is broken is <NUM> MPa or more and <NUM> MPa or less. Preferably, the breaking elongation is <NUM>% or more and <NUM>% or less. More preferably, the breaking elongation is <NUM>% or more and <NUM>% or less and the tensile strength is <NUM> MPa or more and <NUM> MPa or less.

The insulating layer <NUM> is formed by extruded-coating on the outer periphery of the conductor <NUM> to be coated on the outer peripheral side of the conductor <NUM>. The insulating layer <NUM> has a solid structure in which a resin material is filled between a plurality of small-diameter conductors <NUM> arranged on the inner side, and is coated to be in close contact with the conductor <NUM>. Since the insulating layer <NUM> has a solid structure rather than a foamed layer, the conductor <NUM> is less likely to deform.

The insulating layer <NUM> is formed of a flame retardant polyolefin resin, such as, for example, a flame retardant cross-linked polyethylene to which flame retardancy is imparted by blending a flame retardant. The thickness of the insulating layer <NUM> is about <NUM> to <NUM>, and the outer diameter of the insulating layer <NUM> is about <NUM> to <NUM>. The insulating layer <NUM> may be formed of other materials such as ethylene-vinyl acetate copolymer resin (EVA), ethylene-ethyl acrylate copolymer resin (EEA), ethylene-methyl acrylate copolymer resin (EMA), fluorine resin, and the like.

According to the electronic wire <NUM> having such a configuration, since the conductor <NUM> has a good balance between tensile strength and breaking elongation, excellent bending resistance and twisting resistance may be obtained even when the diameter is small.

<FIG> shows an example of a cable. The cable <NUM> is used as a cable for transmitting electricity to a motor or the like.

As shown in <FIG>, the cable <NUM> includes a plurality of (two in this example) electronic wires 1A and 1B and a jacket <NUM> provided on the outer peripheral side of the electronic wires 1A and 1B. In this example, the two electronic wires are referred to as a first electronic wire 1A and a second electronic wire 1B.

The first electronic wire 1A and the second electronic wire 1B are electronic wires which have the same structure as the electronic wire <NUM> (see <FIG>) described above. The first electronic wire 1A and the second electronic wire 1B are twisted together and formed as a twisted pair electronic wire <NUM>.

The jacket <NUM> is formed by extruded-coating on the outer periphery of the twisted pair electronic wire <NUM> to be coated on the outer peripheral side of the twisted first electronic wire 1A and the second electronic wire 1B (twisted pair electronic wire <NUM>). The jacket <NUM> is formed of flame retardant cross-linked polyurethane. The outer diameter of the jacket <NUM>, that is, the outer diameter of the cable <NUM> is about <NUM> to <NUM>.

In this example, the jacket <NUM> is formed by a single coating layer (single layer), but may be formed by a plurality of coating layers (multilayer), for example. At least the outermost coating layer is formed of polyurethane resin so that the outer peripheral surface of the jacket <NUM> is polyurethane resin.

In order to facilitate the operation of removing the jacket <NUM> and taking out the first electronic wire and the second electronic wire, a release layer (not shown) may be provided between the first electronic wire and the jacket and between the second electronic wire and the jacket. For the release layer, a film may be wound, or a powder such as talc may be coated, or a thin gel layer may be provided.

According to the cable <NUM> having such a configuration, since the first electronic wire 1A and the second electronic wire 1B having a good balance between tensile strength and breaking elongation are used, it is possible to obtain excellent bending resistance and twisting resistance even when the diameter is small.

<FIG> shows a modification of the cable <NUM> (see <FIG>). Note that the parts denoted by the same reference numerals as those of the cable <NUM> have the same functions, and thus repeated description thereof is omitted.

As shown in <FIG>, in addition to the first electronic wire 1A and the second electronic wire 1B forming the twisted pair electronic wire <NUM>, the cable <NUM> includes a third electronic wire 5A and a fourth electronic wire 5B having a diameter smaller than those of the first electronic wire 1A and the second electronic wire 1B.

The third electronic wire 5A and the fourth electronic wire 5B each include a conductor <NUM>, and an insulating layer <NUM> provided to be coated on an outer periphery of the conductor <NUM>. The third electronic wire 5A and the fourth electronic wire 5B are electronic wires having substantially the same structure. Note that the third electronic wire 5A and the fourth electronic wire 5B may be twisted together to form a twisted pair electronic wire, or may be arranged in parallel along the length direction of the cable <NUM>.

The conductor <NUM> is formed as a twisted wire in which a plurality of wires formed of an annealed copper wire are twisted together, for example. The diameter of the wire is about <NUM>, for example. The number of wires forming the conductor <NUM> is about <NUM> to <NUM>, for example. The cross-sectional area of the conductor <NUM> is about <NUM> to <NUM><NUM>. The material of the wires forming the conductor <NUM> may be any material having predetermined conductivity and flexibility, such as a copper alloy wire formed of a copper alloy, a tin-plated annealed copper wire, and the like, in addition to the annealed copper wire described above.

The insulating layer <NUM> is formed of a flame retardant cross-linked polyolefin resin, for example. The thickness of the insulating layer <NUM> is about <NUM> to <NUM>, and the outer diameter of the insulating layer <NUM> is about <NUM> to <NUM>. The insulating layer <NUM> may be the same as the insulating layer of the electronic wire <NUM>. Polyurethane may be used.

For example, a thick line may be used as a power supply line and a thin line may be used as a signal line. Since a thick electronic wire is weak in terms of bending resistance, only for the thick electronic wire, a conductor having a breaking elongation of <NUM>% or more and <NUM>% or less, and a tensile strength of <NUM> MPa or more and <NUM> MPa or less (preferably, the breaking elongation is <NUM>% or more and <NUM>% or less, and the tensile strength is <NUM> MPa or more and <NUM> MPa or less, and more preferably, the breaking elongation is <NUM>% or more and <NUM>% or less, and the tensile strength is <NUM> MPa or more and <NUM> MPa or less) may be used. Alternatively, this conductor may be used for both the thick electronic wire and the thin electronic wire.

The cable <NUM> having such a configuration also has the same effect as the cable <NUM>.

The cables of the Examples <NUM> and <NUM> and Comparative Examples <NUM> and <NUM> to be described below were prepared, and the bending test and the twisting test were carried out with respect to each cable.

In Example <NUM>, <NUM> wires having an outer diameter of <NUM> annealed at <NUM> for <NUM> seconds were twisted to form a small-diameter conductor (twisted wire) <NUM>, and seven small-diameter conductors <NUM> were twisted to form a double twisted wire to form a conductor <NUM> having a cross-sectional area of <NUM><NUM>. This conductor has a breaking elongation of <NUM>% and a tensile strength of <NUM> MPa. Electronic wires <NUM> (1A and 1B) having an outer diameter of <NUM> was formed by coating the outer periphery of the conductor <NUM> with an insulating layer <NUM> formed of cross-linked polyethylene. The two electronic wires 1A and 1B were twisted to form a twisted pair electronic wire <NUM>, and the outer periphery of the twisted pair wire <NUM> was coated with a jacket <NUM> formed of cross-linked polyurethane to prepare a cable <NUM> having an outer diameter of <NUM>.

In Comparative Example <NUM>, a conductor and a cable having the same configuration as the cable of Example <NUM> were prepared using a wire of an outer diameter of <NUM> formed of annealed copper wire. The breaking elongation of the conductor of Comparative Example <NUM> was about <NUM>%, and the tensile strength was <NUM> MPa.

The bending resistance of the cable was evaluated in accordance with the bending test specified in ISO <NUM>: <NUM> (E) <NUM>. In this bending test, as shown in <FIG>, the cable C was passed through between the pair of mandrels <NUM>, the cable C was vertically suspended, the upper end of the cable C was held by the chuck <NUM>, and a weight <NUM> of <NUM> N/mm<NUM> (5N per conductor cross-sectional area of <NUM><NUM>) was attached to the lower end thereof. By bending the chuck <NUM> in a pendulum shape along the circumference centered between the mandrels <NUM>, the cable C was repeatedly bent to be -<NUM> ° to + <NUM> ° toward the respective mandrels <NUM> sides. The diameter of the mandrel <NUM> was <NUM>. After bending <NUM>,<NUM> times, the conductor forming the cable C was examined for the presence or absence of breakage.

The mandrel <NUM> and the weight <NUM> in <FIG> were removed, the cable C having a length of <NUM> was vertically suspended, and the upper end and the lower end of the cable C were held by the chucks <NUM>, respectively. The clamp at the lower end was twisted from -<NUM>° to + <NUM>° to the left and right around the axis of the cable C. After twisting <NUM>,<NUM> times, the conductor forming the cable C was examined for the presence or absence of breakage.

Claim 1:
A cable (<NUM>, <NUM>) comprising:
a twisted pair electronic wire (<NUM>) in which two electronic wires (1A, 1B) are twisted together; and
a jacket (<NUM>) coated on the twisted pair electronic wire (<NUM>), wherein
an outer peripheral surface of the jacket (<NUM>) is a polyurethane resin,
the electronic wire (1A, 1B) includes:
a conductor (<NUM>) made of annealed copper; and
a resin insulating layer (<NUM>) coated on the conductor (<NUM>),
the conductor (<NUM>) is a double twisted wire (<NUM>) in which twisted wires formed by twisting a plurality of wires are twisted,
a diameter of each wire of the plurality of wires is <NUM> or more and <NUM> or less,
a cross-sectional area of the conductor (<NUM>) is <NUM><NUM> or more and <NUM><NUM> or less,
a breaking elongation of the conductor (<NUM>) is <NUM>% or more and <NUM>% or less,
a tensile strength of the conductor (<NUM>) is <NUM> MPa or more and <NUM> MPa or less, and
the insulating layer (<NUM>) has a solid structure disposed to be in close contact with the conductor (<NUM>).