WO2018088419A1 - Electric wire conductor, coated electric wire, and wire harness - Google Patents

Abstract

Provided are: an electric wire conductor capable of both being flexible and saving space; and a coated electric wire and a wire harness that comprise said electric wire conductor. The electric wire conductor 10 comprises twisted wire being a plurality of twisted strands 1 and has a cross-section intersecting the axial direction of the twisted wire and having a flat section having a flat shape. The cross-section of the flat section has a porosity of at least 17%, said porosity being the proportion of spaces not occupied by strands. The coated electric wire has said electric wire conductor 10 and an insulator covering the outer circumference of the electric wire conductor 10. Also provided is a wire harness including said coated electric wire.

Description

Wire conductor, covered wire, wire harness

The present invention relates to an electric wire conductor, a covered electric wire, and a wire harness, and more specifically includes an electric wire conductor made of a stranded wire, a covered electric wire having an insulator on the outer periphery of such an electric wire conductor, and such an covered electric wire. It relates to a wire harness.

A flat cable configured using a flat conductor is known. By using a flat cable, compared with the case where the general electric wire provided with the conductor with a substantially circular cross section is used, the space which occupies in the case of arrangement can be made small.

In conventional flat cables, a flat conductor is often used as a conductor, as described in Patent Document 1 and the like. A flat conductor is formed by forming a metal single wire into a square cross section.

JP 2014-130739 A

A flat conductor has relatively high flexibility in the direction along the height (thickness) direction of a flat cross section, and is easy to bend. However, in the direction along the width direction of the flat cross section, it is difficult to bend because it is low in flexibility and hard. As described above, a flat cable having a flat conductor is difficult to bend in a specific direction, and workability at the time of routing is reduced.

An object of the present invention is to provide an electric wire conductor that can achieve both flexibility and space saving, and a covered electric wire and a wire harness provided with such an electric wire conductor.

In order to solve the above problems, the electric wire conductor according to the present invention comprises a stranded wire obtained by twisting a plurality of strands, and a cross section intersecting the axial direction of the stranded wire has a flat portion having a flat shape, In the cross section of the flat portion, a void ratio, which is a ratio of voids not occupied by the strands, is 17% or more.

Here, the porosity is preferably 40% or less.

The deformation rate from the circular shape of the wire in the cross section of the flat part may be smaller than the central part of the flat part in a portion facing the outer periphery of the flat part. In addition, the deformation rate of the strands from the circular shape may be 50% or less of the central portion of the flat portion in the portion facing the outer periphery of the flat portion. And the deformation | transformation rate from the circular shape of the said strand in the cross section of the said flat part is good in the site | part which faces the outer periphery of the said flat part being 10% or less.

The electric wire conductor may have a continuous gap that can accommodate two or more of the strands in the cross section of the flat portion.

The cross section of the flat portion may have opposite sides parallel to each other along the width direction of the flat shape. In this case, the deformation rate from the circular shape of the wire in the cross section of the flat portion may be smaller than the central portion of the flat portion at the end of the flat portion on the opposite side.

The length of the flat portion in the width direction of the flat portion may be at least three times the length in the height direction intersecting the width direction.

The cross section of the flat part may be a quadrangle. Moreover, the cross section of the said flat part is good in it being a rectangle.

The wire conductor may have the flat portion and a low flat portion having a flatness lower than that of the flat portion in the axial direction.

The number of strands constituting the stranded wire is preferably 50 or more.

The stranded wire may be made of copper or a copper alloy and have a conductor cross-sectional area of 100 mm ² or more, or may be made of aluminum or an aluminum alloy and have a conductor cross-sectional area of 130 mm ² or more.

In the flat portion, the wire conductor includes a first direction and a second direction in which the stranded wires face each other, and a third direction and a fourth direction that cross each other and face each other. It is good that it is rolled from the direction.

The covered electric wire according to the present invention has the above-described electric wire conductor and an insulator covering the outer periphery of the electric wire conductor.

The wire harness according to the present invention includes the above-described covered electric wire.

Here, the wire harness includes a plurality of covered electric wires as described above, and the plurality of covered electric wires are arranged along at least one of the width direction of the electric wire conductor and a height direction intersecting the width direction. It is good to be. In this case, the wire harness may include at least one of a heat radiating sheet interposed between the plurality of covered electric wires and a heat radiating sheet in common contact with the plurality of covered electric wires. The plurality of covered electric wires may be arranged at least along the height direction. In this case, an interposition sheet made of a heat dissipating material is interposed between the plurality of covered electric wires arranged along the height direction, and further, the plurality of interposition sheets are interconnected to dissipate heat. A connecting member made of a material may be provided.

The wire harness may be disposed along the outer periphery of the columnar member. Or the said wire harness is good to be accommodated in the hollow part of the hollow tubular member which has an opening along a longitudinal direction.

Alternatively, the wire harness may be arranged under the floor of the automobile and constitute a power supply trunk line. Alternatively, the wire harness may constitute an automobile ceiling or floor. In these cases, the wire harness includes a plurality of the above-described covered electric wires, and the plurality of the covered electric wires are arranged along at least the width direction of the electric wire conductor, and have a height dimension that intersects the width direction. It is preferable that the width direction is arranged along the surfaces of the interior material and the sound absorbing material between the interior material and the sound absorbing material of the automobile.

The wire harness includes a first covered electric wire and a second covered electric wire, and the first covered electric wire is a covered electric wire as described above, wherein the electric wire conductor is made of aluminum or an aluminum alloy, In the covered electric wire, the electric wire conductor is preferably made of copper or a copper alloy, has a flatness lower than that of the electric wire conductor of the first covered electric wire, and has a small conductor cross-sectional area. In this case, the conductor cross-sectional area of the second covered wire is preferably 0.13 mm ² or less.

Since the electric wire conductor according to the invention is not a single wire but a twisted wire, it has high flexibility. And by providing the flat part which has a flat cross section, the space required when arranging as an electric wire can be reduced compared with the general electric wire conductor with a substantially circular cross section. Further, when the cross-sectional area of the conductor is increased, if the width direction of the flat shape is widened, the dimension in the height direction can be kept small, so that a large cross-sectional area can be achieved while maintaining space saving.

And since the electric wire conductor concerning the said invention has the porosity of 17% or more, even if the cross section becomes flat, it is easy to keep especially high flexibility. As a result, an electric wire conductor having a particularly high degree of freedom in routing can be obtained.

Here, when the porosity is 40% or less, it is easy to form the flat portion into a sufficiently flat shape. Moreover, it is easy to maintain the formed flat shape. Therefore, the space saving property of the wire conductor can be effectively improved.

When the deformation rate from the circular shape of the strand in the cross section of the flat portion is smaller than the central portion of the flat portion in the portion facing the outer periphery of the flat portion, the stranded wire is formed to form the stranded wire into a flat cross section. The strands located on the outer peripheral portion of the wire are intensively deformed, and a large load due to the deformation is prevented. Moreover, it is prevented that uneven | corrugated structures, such as a sharp protrusion, are formed in the outer peripheral part of an electric wire conductor by the deformation | transformation of a strand.

When the deformation rate from the circular shape of the strand is 50% or less of the central portion of the flat portion at the portion facing the outer periphery of the flat portion, the deformation and load on the outer peripheral portion of the stranded wire as described above In particular, the effect of preventing the concentration of the metal and the formation of the concavo-convex structure on the surface of the electric wire conductor is obtained.

Even when the deformation rate from the circular shape of the wire in the cross section of the flat portion is 10% or less in the portion facing the outer periphery of the flat portion, the deformation to the outer peripheral portion of the electric wire conductor and the load The effect of preventing the concentration and the formation of the uneven structure on the surface of the electric conductor is particularly high.

When the wire conductor has a continuous gap that can accommodate two or more strands in the cross section of the flat portion, the wire conductor bends flexibly by using the movement of the strand to such a gap. Therefore, the effect of keeping the flexibility of the wire conductor high is particularly excellent.

When the cross section of the flat part has opposite sides parallel to each other along the width direction of the flat shape, it is easy to secure a large space on the outer side in the height (thickness) direction of the routed wires, and high savings are achieved. Space can be realized. In particular, when a plurality of electric wires are stacked and routed, useless space is hardly generated.

In this case, if the deformation rate from the circular shape of the wire in the cross section of the flat portion is smaller than the central portion of the flat portion at the opposite ends of the flat portion parallel to each other, to the end portion of the wire conductor Deformation and load concentration can be prevented. In addition, uneven structures such as sharp protrusions tend to be formed at the ends of opposite sides parallel to each other in the outer periphery of the wire conductor, but the deformation rate of the strands at the ends can be kept small. The formation of a concavo-convex structure such as a sharp projection at the end can be effectively prevented.

In addition, when the length of the flat shape of the flat portion is at least three times the length of the height direction intersecting the width direction, in the electric wire conductor, it is possible to ensure flexibility and to increase the height in the width direction. High space-saving performance in the height direction due to the small size in the vertical direction can be achieved at the same time.

In addition, when the cross-section of the flat part is a quadrangle, it is possible to reduce the wasted space generated between the wires when multiple wires are arranged or stacked, and to integrate the wires at high density It becomes.

Furthermore, when the cross section of the flat portion is rectangular, when a plurality of electric wires are arranged or stacked, the wasteful space generated between the electric wires can be particularly reduced, and the space saving property is particularly excellent. It will be.

When the electric wire conductor has a flat portion and a low flat portion having a flatness lower than that of the flat portion in the axial direction, the flat portion is formed along the axial direction of the electric wire conductor without being joined. The portions having different degrees can be provided in one electric wire conductor, and the characteristics of the respective portions having different flatness can be used simultaneously. For example, by providing a flat part at the center of the electric wire conductor and providing low flat parts with a substantially circular cross section at both ends, it is possible to save space in the central part and convenience in attaching a member such as a terminal at the end. Can be compatible.

When the number of strands constituting the stranded wire is 50 or more, even if each strand is not greatly deformed, a large gap is left between the strands by changing the relative arrangement of the strands. Can be easily formed into a flat cross section. Therefore, it is easy to achieve both space saving and flexibility in the wire conductor.

When the stranded wire is made of copper or a copper alloy and has a conductor cross-sectional area of 100 mm ² or more, or made of aluminum or an aluminum alloy and has a conductor cross-sectional area of 130 mm ² or more, the cross-section is flat. The effect of achieving both space saving and flexibility can be used particularly effectively. In the case of a wire conductor having a large cross-sectional area such as 100 mm ² or more or 130 mm ² or more, when the cross section is substantially circular, a large arrangement space is required due to the size of the diameter, and the repulsive force against bending is growing. However, even in such a large cross-section electric wire conductor, space saving can be achieved by making the cross section flat, and high flexibility can be obtained particularly in bending in the height direction.

And in the flat part, the stranded wire is rolled from the first direction and the second direction facing each other, and from the third direction and the fourth direction facing each other across the first direction and the second direction. If it is, the electric wire conductor tends to be close to a square in cross section, and the electric wire conductor is excellent in space saving.

Since the covered electric wire according to the present invention has the electric wire conductor as described above, it is possible to achieve both flexibility due to the twisted wire structure of the electric wire conductor and space saving due to the flat shape. Therefore, the arrangement can be performed with a high degree of freedom and space reduction, including the arrangement in which a plurality of covered electric wires are arranged or stacked.

Since the wire harness according to the present invention includes a covered electric wire having the above-described flat electric wire conductor, it is excellent in flexibility and space saving, and is suitable as a wiring material in a limited space such as in an automobile. Can be used.

Here, the wire harness includes a plurality of covered electric wires as described above, and the plurality of covered electric wires are arranged along at least one of the width direction of the electric wire conductor and the height direction intersecting the width direction. In the case where the wire harness is provided, the gap between the plurality of covered electric wires can be suppressed to be small and the wire harness can be configured, so that particularly high space saving can be achieved.

In this case, according to the configuration in which the wire harness includes at least one of the heat dissipation sheet interposed between the plurality of covered electric wires and the heat dissipation sheet that contacts the plurality of covered electric wires in common, the plurality of covered electric wires are flattened. Even if they are arranged close to each other at high density by utilizing the space-saving property due to the shape, the influence of heat generation during energization can be suppressed to a small level.

Further, when a plurality of covered electric wires are arranged at least along the height direction, various narrow spaces such as elongated gaps can be formed using the arrangement in the height direction of the covered electric wires. It can be effectively used for planning.

In this case, an interposition sheet made of a heat dissipating material is interposed between the plurality of covered electric wires arranged along the height direction, and the interposition sheets are connected to each other to form the heat dissipating material. When the connecting material is provided, the plurality of covered electric wires are adjacent to each other with their flat and wide surfaces facing each other, and the heat generated during energization is dissipated outside the array of covered electric wires. However, it is easy to effectively dissipate the heat generated during energization to the outside by providing the interposition sheet. Furthermore, heat can be dissipated more effectively by providing a connecting material for connecting a plurality of intervening sheets.

When the wire harness is disposed along the outer periphery of the columnar member, or when the wire harness is accommodated in the hollow portion of the hollow tubular member having an opening along the longitudinal direction, The columnar member and the tubular member to be configured can be used for supporting the wire harness, and the wiring space for the wire harness can be effectively reduced.

In addition, when the wire harness is arranged under the floor of an automobile and constitutes a power supply trunk line, productivity can be improved and fatigue due to engine vibration or the like can be achieved as compared with a conventional power supply trunk line using a copper plate. The occurrence of destruction can be suppressed.

Or when a wire harness comprises the ceiling or floor | floor of a motor vehicle, in a motor vehicle, while utilizing a space especially without waste, a routing route can be secured, and also when flowing a large current, it is high. Heat dissipation can be achieved. Moreover, it becomes possible to comprise the ceiling surface and floor surface of various shapes according to arrangement | positioning of a covered electric wire.

In these cases, the wire harness includes a plurality of the above-described covered electric wires, and the plurality of the covered electric wires are arranged at least along the width direction of the electric wire conductor and have a height direction dimension that intersects the width direction. According to the configuration in which the width direction is arranged between the interior material and the sound absorbing material of the automobile along the surface of the interior material and the sound absorbing material, the distance between the interior material and the sound absorbing material is kept small. However, the space between the interior material and the sound absorbing material can be effectively used for the wiring harness arrangement. At this time, since the heights of the plurality of covered wires are uniform, the uneven structure by the covered wires is less likely to affect the surface shape of the interior material and the sound absorbing performance of the sound absorbing material.

And the wire harness includes the first covered electric wire and the second covered electric wire, and the first covered electric wire is the above covered electric wire made of aluminum or an aluminum alloy, and the second covered electric wire. When the electric wire is made of copper or a copper alloy, has a lower flatness than the electric wire conductor of the first covered electric wire, and has a smaller conductor cross-sectional area, the electric conductivity of aluminum or aluminum alloy The low space makes it possible to achieve both space saving for the first covered electric wire, which tends to have a large area, and utilization of characteristics such as high conductivity of copper and copper alloy in the second covered electric wire.

In this case, if the conductor cross-sectional area of the second covered electric wire is 0.13 mm ² or less, it is easy to ensure high space saving as the entire wire harness.

It is a perspective view which shows the electric wire conductor concerning one Embodiment of this invention. It is sectional drawing of the said electric wire conductor. It is sectional drawing explaining the rolling of a raw material strand wire. FIG. 3 is a diagram showing various cross-sectional shapes of a wire conductor, and (a) to (d) show different forms. In (b) to (d), the wires are omitted. It is sectional drawing which shows the example of the arrangement | sequence of the covered electric wire in the wire harness concerning one Embodiment of this invention. (A) shows the case where the covered electric wires are arranged in the width direction, and (b) shows the case where the covered electric wires are arranged in the height direction. It is sectional drawing which shows another form in the case of arranging a covered wire | conductor in the width direction. It is a figure which shows the example of the routing structure of a wire harness, (a) is a cylindrical member, (b) has shown the routing structure using the tubular member of cross-sectional U shape. It is the photograph which image | photographed the cross section of the covered electric wire, (a) is the raw material strand wire before rolling, (b) shows the sample 1 with a low compression rate, (b) has shown the sample 2 with a high compression rate. It is the result of the simulation regarding the temperature rising of a covered electric wire.

Hereinafter, the electric wire conductor, the covered electric wire, and the wire harness according to the embodiment of the present invention will be described in detail with reference to the drawings. What coat | covered the outer periphery of the electric wire conductor concerning one Embodiment of this invention with the insulator corresponds to the covered electric wire concerning one Embodiment of this invention. And what integrated the some covered electric wire containing the covered electric wire concerning one Embodiment of this invention hits the wire harness concerning one Embodiment of this invention.

[Wire conductor]
In FIG. 1, the external appearance of the electric wire conductor 10 concerning one Embodiment of this invention is shown with a perspective view. FIG. 2 shows a cross section perpendicular to the axial direction (longitudinal direction) of the wire conductor 10.

(1) Sectional shape of electric wire conductor The electric wire conductor 10 is configured as a stranded wire in which a plurality of strands 1 are twisted together. And the electric wire conductor 10 has a flat external shape in at least one part along an axial direction. That is, the cross section perpendicular to the axial direction of the electric wire conductor 10 has a flat portion having a flat shape. In the present embodiment, the entire area in the axial direction of the electric wire conductor 10 is such a flat portion.

Here, that the cross section of the electric wire conductor 10 has a flat shape means that the width is the length of the longest straight line out of the straight lines that cross the cross section parallel to the sides constituting the cross section and include the entire cross section. A state where W is larger than a height H which is a length of a straight line which is orthogonal to the straight line and includes the entire cross section as a range. The width W is greater than the height H in the cross section of the wire conductor 10 according to the present embodiment shown in FIG.

As long as the cross section of the electric wire conductor 10 has a flat shape, it may have any specific shape. However, in the present embodiment, the cross section of the electric wire conductor 10 has a flat width W direction (width). The opposite sides 11 and 12 are parallel to each other along the direction x). That is, it is possible to draw two straight lines 11 and 12 parallel to the width direction x by circumscribing the outer strand 1 constituting the cross section of the wire conductor 10. In this specification, regarding the shape of the electric wire conductor 10, the concept indicating the relationship between lines and surfaces, such as parallel and vertical, includes an angle deviation of approximately ± 15 °, an R shape with chamfered corners, and the like. , Including errors from geometric concepts. In addition, the concepts such as sides, straight lines, and planes include curves and curved surfaces having an angle of about 15 ° from the geometric straight lines and planes.

In this embodiment, the cross section of the wire conductor 10 is a rectangle. In the figure, for the sake of easy understanding, the number of the strands 1 constituting the electric wire conductor 10 is reduced.

The electric wire conductor 10 according to the present embodiment has a flat cross section, so that when the electric wire conductor 10 is arranged in the form of a covered electric wire or the like rather than the electric wire conductor having the same conductor cross sectional area, the electric wire conductor 10 is arranged. The space required for the measure can be reduced. That is, a space where another electric wire or another member cannot be arranged around a certain electric wire can be reduced. In particular, the space occupied by the electric wires along the height direction y can be reduced, and it is easy to achieve space saving. As a result, it becomes easy to arrange other electric wires and other members in the space outside the electric wires in the vertical direction (± y direction). For example, when routing an electric wire along the routing surface, if the flat surface of the wire, that is, a plane parallel to the width direction x is set along the routing surface, It is easy to secure a space in the direction facing the arrangement surface across the surface. Furthermore, even when it is desired to increase the conductor cross-sectional area of the electric wire conductor 10, the space saving property in the height direction y can be maintained by increasing the width W while the height H is reduced.

In particular, when the wire conductor 10 has the opposite sides 11 and 12 parallel to the width direction x in the cross section, a wide space is secured in the vertical direction (± y direction) of the routed wires. It is excellent in space saving. In particular, when a plurality of electric wires are stacked so as to overlap another electric wire above one electric wire, a gap generated between the plurality of electric wires along the height direction y can be reduced. In addition, integrating | stacking a some electric wire includes both the case where it is set as the form which put together the some electric wire with the insulating material etc., and the case where it arrange | positions the several independent electric wire adjoining.

Furthermore, when the wire conductor 10 has a rectangular cross section, a wide space can be secured above and below (± y direction) and side (± x direction) of the wire conductor 10, further enhancing space saving. Can do. In particular, when stacking a plurality of electric wires such that another electric wire is stacked above one electric wire and other electric wires are arranged side by side of one electric wire, the height direction y And the clearance gap which arises between several electric wires along the width direction x can be made small.

As described above, the electric wire conductor 10 according to the present embodiment is made of a stranded wire in which a plurality of strands 1 are twisted together, and the stranded wire has a flat outer shape. Therefore, the electric wire conductor 10 has high flexibility in each direction. A flat conductor as shown in Patent Document 1 exhibits a certain degree of flexibility in the height direction of a flat shape, but has low flexibility in the width direction and is hard in the width direction and difficult to bend. On the other hand, the electric wire conductor 10 according to the present embodiment made of a stranded wire has high flexibility not only in the height direction y but also in the width direction x, and is easily bent.

As described above, the electric wire conductor 10 according to the present embodiment achieves both flexibility in arrangement by flexibility and space saving. For example, in automobiles, the number of electric wires and parts to be installed is increasing due to recent high functionality. Moreover, in electric vehicles and the like, the increase in current has progressed, and the wire diameter has also increased. Therefore, the space where each electric wire can be arranged is decreasing. However, if the electric wire conductor 10 according to the present embodiment is used, the arrangement of electric wires can be performed by effectively using a small space by utilizing space saving and flexibility. The effect is particularly great when a large number of electric wires are integrated or when an electric wire having a large conductor cross-sectional area is used.

In the present embodiment described so far, the wire conductor 10 has a rectangular cross section. However, as described above, the cross section of the wire conductor 10 may have any shape as long as it has a flat shape. 4B to 4D show other examples of the cross-sectional shape. In these drawings, the element wire 1 is omitted, and only a circumscribed figure that approximates the outer shape of the cross section, that is, the cross section of the entire wire conductor is shown. FIG. 4B shows a cross section of an oval shape (a shape having a semicircle at both ends of a rectangle). 4C shows a trapezoidal cross section and FIG. 4D shows a parallelogram cross section as a quadrilateral cross section other than the rectangle as described above. Since the electric wire conductor 10 has a rectangular cross section, a large number of electric wire conductors 10 can be arranged in the height direction y and the width direction x with small gaps, and the space saving property when collecting a large number of electric wires is excellent. This effect is particularly remarkable when the cross-sectional shape is rectangular as described above.

(2) Air gap in cross section of electric wire conductor Furthermore, the electric wire conductor 10 according to the present embodiment has a porosity of 17% or more in the cross section of the flat portion. The void ratio in the cross section of the electric wire conductor 10 is the area occupied by the entire electric wire conductor 10 in the cross section perpendicular to the axial direction of the electric wire conductor 10, that is, the area of the region surrounded by the outline as the entire electric wire conductor 10 It is defined as the ratio of the area of the void that is not occupied by the strand 1.

As described above, the electric wire conductor 10 has high flexibility in the height direction y and the width direction x due to the effect of the flat shape, and is easily bent. In the cross section of the wire conductor 10, a sufficient gap is secured such as 17% or more, so that the gap in the wire conductor 10 is bent when the wire conductor 10 is bent along the height direction y or the width direction x. By moving the element wire 1 using the wire conductor 10, the wire conductor 10 is more easily bent without difficulty, and the flexibility of the wire conductor 10 is easily increased. From the viewpoint of further enhancing the flexibility, the porosity is more preferably 20% or more, or 25% or more.

The upper limit of the porosity is not particularly defined, but it is preferably 40% or less from the viewpoint of easily forming the electric conductor 10 into a flat shape by rolling or the like and easily maintaining the formed flat shape. More preferably, it is 35% or less.

In the cross section of the wire conductor 10, a small gap is formed in the region between the strands 1. The void ratio defined above is a ratio of the area occupied by the total area of the small voids in the cross section of the wire conductor 10, and the total area of the voids occupies a predetermined ratio or more in the cross section of the wire conductor 10. Thus, the flexibility of the electric wire conductor 10 is enhanced, but in addition, the size of the area of each gap formed in the region between the strands 1 also contributes to the improvement of the flexibility of the electric wire conductor 10. . In other words, the presence of gaps having a certain size as a continuous region in the cross-section of the wire conductor 10 rather than the uniform distribution of minute gaps improves the flexibility of the wire conductor 10. It is valid. Specifically, it is preferable that the cross section of the wire conductor 10 has a continuous gap that can accommodate two or more strands 1, or even three or more strands. It is because the flexible bending of an electric wire is assisted by the strand 1 moving to such a big space | gap. Here, as the strand 1 for determining whether or not it can be accommodated in the gap, the strand 1 surrounding the gap of interest, or a circular cross section having the same cross-sectional area as the arbitrary strand 1 constituting the wire conductor 10 It is sufficient to use the above-mentioned wire. For example, in FIG. 4A, the gap indicated by the symbol v can accommodate two or more strands.

In addition, the area of the electric wire conductor 10 and the space | gap performs photography etc. with respect to the cross section obtained by cut | disconnecting or grinding | polishing about the covered electric wire 20 which provided the insulator 21 in the electric wire conductor 10 or the outer periphery, It can be evaluated by actual measurement. At this time, an operation such as cutting may be performed after embedding the wire conductor 10 or the covered wire 20 in a transparent resin or the like as appropriate so that the shape or area of the gap is not changed by an operation such as cutting. In addition, the area of the wire conductor 10 and the gap may be evaluated with respect to the entire cross section of the wire conductor 10, or the number of the strands 1 in order to eliminate the influence of the concavo-convex structure in the outermost peripheral portion of the wire conductor 10. However, if the number is sufficiently large, for example, 50 or more, the area of the wire conductor 10 and the gap is evaluated with respect to the inner region excluding the outermost peripheral portion of the wire conductor 10, and instead of the evaluation in the entire cross section. Also good.

(3) Cross-sectional shape of each strand In the electric wire conductor 10 concerning this embodiment, if the cross section is flat as the external shape of the whole electric wire conductor 10, the cross-sectional shape of each strand 1 which comprises the electric wire conductor 10 May be anything. A general metal strand has a substantially circular cross section, and such a strand 1 can be applied also in this embodiment. However, at least some of the plurality of strands 1 may have a cross section deviating from a circle, such as a flat shape. As will be described later, when the raw material stranded wire 10 ′ is rolled into a flat shape, depending on the material constituting the strand 1, at least a part of the strand 1 may be deformed into a flat shape.

In the electric wire conductor 10 according to the present embodiment, in the cross section perpendicularly intersecting the axial direction, the wire 1 in the outer peripheral portion facing the outer periphery of the electric wire conductor 10 rather than the central portion located inside the outer peripheral portion. The deformation rate is small. 1 and 2 schematically show the distribution of the deformation rate of such an element wire 1.

Here, the deformation rate of the element wire 1 is an index indicating how much a certain element wire 1 has a cross section deviating from a circle. The length of the longest straight line that crosses the cross section of a certain strand 1 that is actually included in the wire conductor 10 is defined as the major axis A, and the diameter of a circle having the same area as the sectional area of the strand 1 is defined as the circle diameter R. The deformation rate D of the wire 1 can be expressed as follows.
D = (A−R) / R × 100% (1)
The circle diameter R may be calculated by measuring the cross-sectional area of the actual strand 1, or when the diameter of the strand 1 before undergoing deformation due to rolling or the like is known, When a portion where the strand 1 is not deformed (which will be described later as a low flat portion) coexists, the diameter of the strand 1 that has not undergone deformation may be adopted as the circular diameter R. Moreover, only the strand 1 arrange | positioned at the outermost periphery of the electric wire conductor 10 is employ | adopted as the strand 1 of an outer peripheral part, and only the strand 1 arrange | positioned at the center of a conductor is employ | adopted as the strand 1 of a center part. However, it is preferable to estimate the deformation rate as an average value for a plurality of strands 1 included in a region over a certain area from the viewpoint of reducing the influence of variations in the deformation of the strands 1. For example, a region surrounded by a quadrilateral having sides extending about 10 to 30% of the width W of the wire conductor 10 or a circle having such a diameter includes the outermost periphery or the center of the wire conductor 10. And these regions may be adopted as the outer peripheral portion and the central portion, respectively.

Although the electric wire conductor 10 according to the present embodiment has a flat cross-sectional shape, the wire 1 positioned on the outer peripheral portion in the vertical direction (± y direction) of the electric wire conductor 10 can be flatly deformed in the cross section. For example, a flat cross-sectional shape can be formed more efficiently than the deformation of the strand 1 at the center. However, when the outer strand 1 is intensively deformed, the load is concentrated on the outer strand 1 and the physical properties of the strand 1 are determined by It will be very different. Moreover, the shape of the strand 1 of the outer peripheral part of the electric wire conductor 10, especially the strand 1 located in the outermost periphery of the electric wire conductor 10 prescribes | regulates the outline shape of the whole electric wire conductor 10, and those strands 1 are large. If it is deformed, an unnecessary uneven structure may be brought about on the surface shape of the wire conductor 10. Examples of such a concavo-convex structure include sharp protrusions (burrs) that can be formed when the raw material stranded wire 10 ′ is processed into a flat shape. In particular, the burr is easily formed at the end portion in the width direction (± x direction) of the wire conductor 10.

Therefore, in the electric wire conductor 10, if the deformation rate of the outer strand 1 is smaller than the deformation rate of the central strand 1, the outer strand 1 is deformed. Concentration of loads and formation of unnecessary uneven structures on the outer periphery of the wire conductor 10 can be avoided. In the electric wire conductor 10 according to the present embodiment, a porosity of 17% or more is ensured as described above, and the strands 1 take various relative arrangements using the gaps between the strands 1. Therefore, the cross-section of the wire conductor 10 can be formed into a desired flat shape using the relative arrangement of the strands 1 without greatly deforming the shape of each strand 1 itself.

From the viewpoint of effectively avoiding deformation and concentration of load on the strands 1 positioned on the outer periphery of the wire conductor 10 and the formation of unnecessary uneven structures on the surface of the wire conductor 10, the deformation rate of the strand 1 in the center portion The ratio of the deformation ratio of the outer peripheral element wire 1 to the outer peripheral area (peripheral deformation ratio: outer peripheral deformation ratio / central deformation ratio × 100%) is 70% or less, more preferably 50% or less, and 25% or less preferable. Moreover, it is preferable that the value of the deformation rate of the strand 1 of an outer peripheral part is 10% or less, Furthermore, 5% or less. The smaller the deformation rate of the strand 1 of the outer peripheral portion, the better. The lower limit is not particularly provided.

The deformation rate of the strand 1 in the center is not particularly limited, but from the viewpoint of avoiding application of a load to the strand 1 due to excessive deformation, it may be 50% or less, and further 30% or less. preferable. On the other hand, from the viewpoint of effectively achieving the flat shape of the cross section of the wire conductor 10 while suppressing the deformation of the wire 1 at the outer peripheral portion to be small, the deformation rate of the central portion is 10% or more, and further 20%. The above is preferable.

When the cross section of the electric wire conductor 10 has the opposite sides 11 and 12 parallel to the width direction x, in particular, when it is made of a rectangle, the width direction end of the cross section, that is, both ends of the opposite sides 11 and 12 parallel to each other. It is preferable to keep the deformation rate of the strand 1 particularly small. When the cross section of the electric wire conductor 10 is formed into those shapes, the deformation rate of the end portion in the width direction is increased in order to produce parallel opposite sides 11 and 12 along the width direction x and a square structure close to a right angle. It is easy. Further, sharp burrs are likely to be formed at the ends when processing for forming the wire conductor 10 is performed by compression of the raw material stranded wire 10 ′ or the like. From the viewpoint of avoiding these phenomena, in the cross section of the wire conductor 10, the deformation rate of the element wire 1 at the end portion is 70% or less, more preferably 50% of the deformation rate of the element wire 1 at the center portion in the outer peripheral portion. Hereinafter, it is preferable to be 25% or less. And it is preferable to make it the value of the deformation rate of the strand 1 of an edge part to be 10% or less, Furthermore, it is 5% or less. Moreover, when the deformation rate of the strand 1 is compared between the end portion and the portion excluding the end portion, that is, the side portion corresponding to the middle portion of the opposite sides 11 and 12 along the width direction x, in the outer peripheral portion. In addition, it is preferable that the deformation rate of the end portion is smaller than the deformation rate of the side portion. That is, it is preferable that the end portion, the side portion, and the central portion are arranged in this order from the one with the smaller deformation rate of the strand 1.

In the electric wire conductor 10, as the number of the strands 1 increases, the deformation rate of the strand 1 at the outer peripheral portion is kept smaller than that at the central portion, while maintaining a high porosity of 17% or more and a flat cross section. Easy to mold into. For example, when the number of the strands 1 is 50 or more, such a state is easily achieved due to the diversity of mutual arrangement of the strands 1. On the other hand, if the number of the strands 1 is less than 50, even if the external strand 1 is deformed at a deformation rate equal to or larger than that of the strand 1 at the center, the wire conductor 10 From the viewpoint of obtaining sufficient flexibility, it is preferable to secure a porosity of 17% or more.

(4) Wire conductor material and conductor cross-sectional area The wire 1 constituting the wire conductor 10 may be made of any conductive material including a metal material. As typical materials constituting the strand 1, copper and copper alloy, and aluminum and aluminum alloy can be cited. These metal materials are suitable for constituting the electric wire conductor 10 according to the present embodiment in that it is easy to perform a process of forming a stranded wire and rolling it into a flat shape and to easily maintain the flat shape. It is. As the strand 1 which comprises the electric wire conductor 10, you may use what consists of the same material altogether, or may mix and use the multiple types of strand 1 which consist of different materials.

What is necessary is just to select the conductor cross-sectional area of the electric wire conductor 10 arbitrarily according to the desired electrical conductivity. However, the larger the conductor cross-sectional area, the easier it is to form a flat shape by rolling or the like, and it is easier to maintain the flat shape once formed firmly. From these viewpoints, as a suitable conductor cross-sectional area, when the wire 1 constituting the wire conductor 10 is made of copper or a copper alloy, 16 mm ² or more, and when made of aluminum or an aluminum alloy, 40 mm ² or more It can be illustrated.

Further, in a large area where the conductor cross-sectional area is 100 mm ² or more, if the cross-section of the wire conductor is substantially circular, the diameter of the circle of the cross-section becomes large, so that a large space is required for the routing, and bending The repulsive force at the time of adding is increased, and it becomes difficult to ensure sufficient flexibility in the arrangement. However, by using the electric wire conductor 10 having a flat cross section, the height H can be made smaller than the electric wire conductor having a substantially circular cross section with the same conductor cross sectional area. As a result, the space occupied by the electric wire conductor 10 in the height direction y can be reduced, and the repulsive force when the electric wire conductor 10 is bent in the direction along the height direction y is reduced, ensuring the flexibility required for the routing. It becomes easy to do. By making the wire conductor 10 having a large conductor cross-sectional area a flat cross-sectional shape, the effect of increasing the heat dissipation of the wire conductor 10 can also be obtained. From the viewpoint of effectively using these effects such as ensuring flexibility, when the wire conductor 10 is made of copper or a copper alloy, the conductor cross-sectional area is preferably 100 mm ² or more. When the electric wire conductor 10 is made of aluminum or an aluminum alloy, the conductor cross-sectional area is preferably 130 mm ² or more. The wire conductor 10 having a large conductor cross-sectional area is expected to be used as a power supply line in a high-power electric vehicle, for example, and it is necessary to arrange it in a limited space in the vehicle. Space saving and flexibility of the electric wire conductor 10 having a flat cross-sectional shape are useful. In particular, from the viewpoint of reducing the weight of the vehicle, it is effective to configure the electric wire conductor 10 having a large conductor cross-sectional area from aluminum or an aluminum alloy. However, aluminum or an aluminum alloy has lower conductivity than copper or a copper alloy. Therefore, from the viewpoint of ensuring the necessary conductivity, the electric wire conductor 10 having a particularly large conductor cross-sectional area is required, such as 130 mm ² or more.

Moreover, 0.3 to 1.0 mm can be exemplified as a suitable outer diameter of each wire 1 constituting the electric wire conductor 10. The number of strands 1 constituting the wire conductor 10 is determined by the conductor cross-sectional area of the wire conductor 10 and the outer diameter of the strand 1 used. However, as the number of the strands 1 increases, the strands 1 can have various relative arrangements. Therefore, while ensuring a large void ratio of 17% or more, the strands in the outer peripheral portion of the wire conductor 10 are further secured. It becomes easy to form the wire conductor 10 into a flat cross-section while keeping the deformation rate of the wire 1 small. From this viewpoint, the number of the strands 1 is preferably 50 or more, more preferably 100 or more, and 500 or more.

(5) Aspect ratio of electric wire conductor In the cross section of the electric wire conductor 10, the flat aspect ratio (H: W) may be appropriately selected in consideration of a desired space saving property and the like. : About 8 can be exemplified. Within this range, the stranded wire can be formed into a flat shape without difficulty, and a high space-saving property can be secured. Moreover, when using the electric wire conductor 10 for the wiring in a motor vehicle etc., the form which makes height H 3 mm or less can be illustrated as a preferable thing.

As will be described later, when the raw material stranded wire 10 ′ made of a general stranded wire having a substantially circular cross section is rolled to form the electric conductor 10 having a flat cross section, the gap between the strands 1 is accompanied by rolling. In particular, as the aspect ratio of the flat shape of the electric wire conductor 10 is larger (as the width W is larger than the height H), the porosity tends to be smaller. However, for example, when the aspect ratio (H: W) is 1: 3 or more, that is, when the width W of the wire conductor 10 is three times or more of the height H, the porosity is 17% or more as described above. Is ensured, the wire conductor 10 can easily achieve both high space saving and flexibility.

Further, by making the wire conductor 10 have a flat cross-sectional shape, the heat dissipation of the wire conductor 10 can be enhanced by the effect of increasing the surface area, compared to the case of a substantially circular cross section. As a result, even when the same current flows, the temperature rise of the wire conductor 10 is smaller when the cross section of the wire conductor 10 is flat than when the cross section is circular. In other words, when the upper limit value of the temperature rise is determined, the range of the upper limit value is smaller in the case where the cross section of the electric wire conductor 10 is flat than in the case where the cross section is substantially circular. The same amount of current can flow while suppressing the temperature rise. The effect of improving heat dissipation increases as the aspect ratio of the wire conductor 10 increases. For example, as shown in a later embodiment, when the aspect ratio is 1: 3 or more, even when the conductor cross-sectional area is approximately 90% of the wire conductor 10 having a substantially circular cross section, the temperature rise during energization is suppressed to the same level. It becomes possible. Furthermore, the aspect ratio is preferably set to 1: 5 or more.

(6) Other forms Up to this point, the entire axial direction of the electric wire conductor 10 has been treated as a flat portion having a flat cross section. However, the flat portion may occupy only a partial region in the axial direction of the wire conductor 10. That is, an example in which a flat portion and a low flat portion having a lower flatness (a smaller W / H value) than the flat portion is provided adjacent to each other along the axial direction of the electric wire conductor 10 is illustrated. Can do. Between the flat part and the low flat part, all the strands 1 are integrally continuous, and the cross-sectional shape as the electric wire conductor 10 whole differs. As a low flat part, the structure of cross-section substantially circular whose flatness is substantially 1 can be illustrated. By providing the flat portion and the low flat portion continuously in one electric wire conductor 10, it is possible to obtain the electric wire conductor 10 having the characteristics brought about by the respective parts without depending on bonding or the like. it can.

In the low flat portion, it is preferable that the deformation rate of the wire 1 is smaller than that of the flat portion, corresponding to the low degree of flattening of the wire conductor 10 by rolling or the like. In particular, in a low flat portion having a substantially circular cross section with a flatness of substantially 1, it is preferable that the cross section of the wire 1 is also substantially circular.

The flat portion and the low flat portion may be arranged in any order along the axial direction of the electric wire conductor 10. However, the flat portion is provided in the central portion in the axial direction, and both ends thereof are low in shape such as a substantially circular cross section. A form in which the flat portion is provided can be exemplified as a suitable one. In this case, it is conceivable to use flat portions for the arrangement in a narrow space and attach other members such as terminals to the low flat portions at both ends. Then, both the space-saving property and flexibility of the flat part and the convenience of attaching other members due to the circular shape of the low flat part or a cross-sectional shape close thereto can be used. Furthermore, in a flat part, the some site | part from which flatness differs may be provided adjacent to each other.

[Manufacturing method of electric wire conductor]
As shown in FIG. 3, the wire conductor 10 according to the present embodiment can be formed by rolling a raw material stranded wire 10 ′ obtained by twisting a plurality of strands 1 into a substantially circular cross section. Under the present circumstances, force F1, F2 is applied from the mutually opposing 1st direction and 2nd direction perpendicular | vertical to the axial direction of raw material strand wire 10 ', and force F1, F2 is compressed by compressing raw material strand wire 10'. The flat electric wire conductor 10 which makes the application direction of F2 the height direction y can be obtained.

Furthermore, in addition to the forces F1 and F2 from the first direction and the second direction, the forces F3 and F4 are applied to the raw material stranded wire from the third direction and the fourth direction that cross each other and face each other. By applying to 10 ', it becomes easy to shape | mold the obtained electric wire conductor 10 in a cross-sectional square. In particular, by applying the forces F3 and F4 from a direction perpendicular to the forces F1 and F2, the obtained wire conductor 10 can be easily formed into a rectangular cross section. In these cases, by setting the forces F1 and F2 to be larger than the forces F3 and F4, it is possible to obtain the wire conductor 10 having a high flatness (a large W / H value). The forces F1 and F2 and the forces F3 and F4 may be applied at the same time. However, after the forces F1 and F2 are first applied, the forces F1 ′ and F2 ′ are applied again from the same direction as the forces F1 and F2, and simultaneously the forces F1 and F2 are applied. By applying F3 and F4, it is possible to obtain the wire conductor 10 having a high flatness and a well-shaped square shape (particularly a rectangular shape). When the flatness is changed along the axial direction of the electric wire conductor 10, the applied force may be changed during the rolling along the axial direction.

Application of force to the raw material stranded wire 10 'may be performed by, for example, providing rollers facing each other and passing the raw material stranded wire 10' between the rollers. Rolling the raw material stranded wire 10 'along the rotation direction of the roller using a roller, for example, when compressing the raw material stranded wire 10' by drawing using a die, or using a press Compared to the case where the raw material stranded wire 10 'is compressed so as to be crushed, the entire shape of the raw material stranded wire 10' is easily deformed into a flat shape without applying a large load to the raw material stranded wire 10 '. In addition, the load is not concentrated on the outer peripheral portion of the raw material stranded wire 10 ′ in contact with the roller, but the load is easily applied to the entire raw material stranded wire 10 ′ with high uniformity. As a result, by rolling the raw material stranded wire 10 ′ using a roller, it is easier to secure a gap between the strands 1 in the obtained flat conductor conductor 10 than when using a die or a press. . Moreover, it is easy to suppress the deformation rate of each strand 1 including the strand 1 located in the outer peripheral part of the electric wire conductor 10 small. The porosity and the deformation rate of each strand 1 depend on the magnitude of the force applied during rolling (F1, F2, F3, F4, F1 ′, F2 ′) and the shape of the portion in contact with the raw material stranded wire 10 ′ of the roller. Can be adjusted.

Using the roller, the entire raw material stranded wire 10 'is formed into a flat shape while keeping the deformation rate of the wire 1 small, so that in the obtained electric wire conductor 10, the physical property change accompanying the deformation of the wire 1 is kept small. be able to. Therefore, heat treatment or the like for removing the effects of work distortion and work hardening is often not particularly necessary in the rolled wire conductor 10.

[Coated wire]
As described above, the covered wire 20 according to the embodiment of the present invention includes the wire conductor 10 according to the embodiment of the present invention as described above and the insulator 21 that covers the outer periphery of the wire conductor 10. (Refer to FIG. 5 etc.).

The outer shape of the entire covered electric wire 20 including the insulator 21 reflects the outer shape of the electric wire conductor 10, and the electric wire conductor 10 has a flat shape, so that the covered electric wire 20 also has a flat shape. Moreover, since the electric wire conductor 10 has high flexibility in each direction, the covered electric wire 20 also has high flexibility in each direction.

The material of the insulator 21 is not particularly limited, and can be composed of various polymer materials. In addition, the polymer material can appropriately contain a filler and an additive. However, the material and thickness of the insulator 21 may be selected so that the flexibility of the insulator 21 is higher than the flexibility of the wire conductor 10 so as not to impair the high flexibility of the wire conductor 10. preferable. The thickness of the insulator 21 is preferably selected so that the flat shape of the wire conductor 10 is sufficiently reflected as the shape of the entire covered wire 20 and the cross section of the entire covered wire 20 has a flat shape.

The insulator 21 can be configured to integrally surround the entire circumference of the wire conductor 10. In this case, the insulator 21 can be provided by forming a polymer material to be the insulator 21 around the entire circumference of the wire conductor 10 by extrusion or the like. Alternatively, the sheet-like insulator 21 can be configured to sandwich the wire conductor 10 from the top and bottom of the wire conductor 10 in the height direction (± y direction). In this case, the polymer material molded into two sheets may be disposed above and below the electric wire conductor 10 and the sheets may be appropriately joined by fusion, adhesion, or the like.

Even if the covered electric wire 20 is used in the state of a single wire in which the outer periphery of the single electric wire conductor 10 is covered with the insulator 21, a plurality of covered electric wires are integrated, and if necessary, a plurality of covered electric wires 20 can be used using a covering material or the like You may use in the form of the wire harness which integrated the covered electric wire of. Next, the case where it is used in the form of a wire harness will be described.

[Wire Harness]
A wire harness according to an embodiment of the present invention is formed by integrating a plurality of covered electric wires, and at least a part of the plurality of covered electric wires has the flat electric wire conductor 10 as described above. It consists of the covered electric wire 20 concerning embodiment. Even if the wire harness is configured using only the covered electric wire 20 having the flat electric wire conductor 10 as described above, such a covered electric wire 20 and a covered electric wire having a general electric wire conductor having a substantially circular cross section, etc. Other types of covered electric wires may be used in combination. Further, when a wire harness is formed using a plurality of covered electric wires 20 having flat electric wire conductors 10, the materials, shapes, dimensions, etc. of the electric wire conductors 10 and the insulators 21 constituting the plural covered electric wires 20 are mutually May be the same or different. In the wire harness, the integrated plurality of covered electric wires may be integrated together using an insulating material or the like as necessary.

(1) Arrangement of covered electric wires in wire harness When a wire harness is configured using a plurality of covered electric wires 20 having flat electric wire conductors 10, the plurality of covered electric wires 20 may be arranged in any positional relationship. However, as shown in FIG. 5A, the flat wire conductors 10 are arranged in the width direction x (lateral direction), as shown in FIG. 5B, in the height direction y, or in the width direction. A matrix form (see FIG. 7B) in which a plurality of covered electric wires 20 arranged in x are stacked in the height direction y can be exemplified. That is, the form which arrange | positions the some covered electric wire 20 along at least one of the width direction x and the height direction y can be illustrated. As described above, by arranging the plurality of covered electric wires 20 including the flat electric wire conductors 10 in an orderly manner, the gap between the covered electric wires 20 constituting the wire harness can be reduced, and particularly excellent in space saving. It becomes a wire harness.

In particular, when a plurality of covered electric wires 20 are arranged side by side in the width direction x of the flat electric wire conductor 10, the space-saving property brought about along the height direction y by the flat shape of the electric wire conductor 10 is effectively used. Thus, a wire harness can be configured and used for routing. For example, space saving can be effectively utilized when arranging a wire harness in a space with a limited height, or when arranging another member in the vertical direction of the wire harness. Moreover, it is easy to ensure the heat dissipation of each covered electric wire 20.

On the other hand, when the plurality of covered electric wires 20 are arranged side by side in the height direction y of the flat electric wire conductor 10, that is, when stacked along the height direction y, the flat shape of the electric wire conductor 10 causes the width direction to change. Even if the dimension (width W) of x is wide, the wire harness can be configured and used for routing while suppressing the dimension in the width direction x as the entire wire harness. As a result, it is possible to make a plan by utilizing a long and narrow space in the height direction.

Even in the case where a large number of the covered electric wires 20 are arranged close to each other by using a flat shape by contacting the arranged covered electric wires 20 in the wire harness and providing a heat dissipation sheet, the heat dissipation of each covered electric wire 20 is achieved. It becomes easy to secure the sex. Here, the heat radiating sheet is a sheet-like (including plate-like) member made of a heat radiating material having a higher heat radiating property than the covered electric wire 20, and may exemplify a sheet body or a plate made of aluminum or an aluminum alloy. it can. As arrangement | positioning of a thermal radiation sheet | seat, the form provided by interposing between the some covered electric wire 20 which comprises a wire harness, and the form provided in contact with the some covered electric wire 20 in common can be illustrated.

As shown in FIG. 5A, when a plurality of covered electric wires 20 are arranged side by side in the width direction x, they are brought into contact with a surface (flat surface) along the width direction x of each covered electric wire 20 so that common heat dissipation is performed. It is preferable to arrange the sheet 31. By bringing the flat surface having a large area due to the flat shape of the wire conductor 10 into contact with the surface on one side of the heat dissipation sheet 31, the heat dissipation of the covered electric wire 20 can be effectively enhanced. And the structure of the wire harness containing the heat radiating sheet 31 can be simplified by arranging the common heat radiating sheet 31 for the plurality of covered electric wires 20. In the illustrated form, the respective covered electric wires 20 are not in contact with each other along the width direction x. However, in the case of contact, it is preferable that a heat dissipation sheet is interposed between the adjacent covered electric wires 20.

As shown in FIG. 5B, when a plurality of covered electric wires 20 are arranged side by side in the height direction y, it is preferable that a heat radiation sheet is provided as the interposed sheet 32 interposed between the respective covered electric wires 20. . The intervening sheet 32 comes into contact with the flat surface along the width direction x of each covered electric wire 20. When the electric wire conductor 10 has a flat shape, the area of the flat surface is increased, and in the array in which the plurality of covered electric wires 20 are arranged by bringing the large flat surfaces close to or in contact with each other, Although it may be difficult to dissipate the generated heat to the outside, heat dissipation can be promoted by providing the interposition sheet 32 between the covered electric wires 20.

Furthermore, it is preferable that the plurality of intervening sheets 32 provided between the respective covered electric wires 20 are connected to each other by a connecting material 33 made of a heat dissipation material. By providing the connecting material 33, the heat dissipation of each covered electric wire 20 can be improved as compared with the case where only the interposition sheet 32 is provided. The connecting member 33 may be provided as a member specialized for the purpose of heat dissipation of the covered wire 20 via the interposition sheet 32, or a member provided for another purpose may be used as the connecting member 33. For example, by using a columnar member constituting a car body of an automobile as the connecting member 33, the member serves as a structural member of the car body and a connecting member that assists heat dissipation of the covered electric wire 20 via the interposition sheet 32. It can also serve as a support member for attaching a wire harness composed of a plurality of covered electric wires 20 as a role of 33.

As shown in the following examples, as in the case of FIG. 5A, when the heat dissipation sheet 31 made of aluminum or aluminum alloy is provided in contact with the flat surface along the width direction x of the covered electric wire 20, The cross-sectional area of the heat dissipation sheet 31 in the cross section perpendicular to the axial direction of the covered electric wire 20 is 1.5 times or more the conductor cross-sectional area of the electric wire conductor 10 constituting the covered electric wire 20 per covered electric wire, and further 4 It is preferable that it is twice or more. If it does so, the heat dissipation of the covered electric wire 20 can be improved effectively.

(2) Arrangement to automobile As described above, by using a wire harness including the covered electric wire 20 having the flat electric wire conductor 10 as, for example, a wiring material for an automobile, excellent space-saving properties are effectively utilized. can do. By arranging such a wire harness along, for example, a floor or a frame of a vehicle, a limited space under the floor or around the frame can be effectively used for the arrangement. At this time, particularly excellent space saving can be obtained by arranging the wire harness so that the width direction x of the wire conductor 10 is substantially parallel to the floor surface or the surface of the frame material.

Conventionally, a general wire harness is composed of a bundle of covered electric wires having a substantially circular cross section, and becomes bulky as a whole wire harness. The space in which occupants can stay may become smaller. However, as described above, by using the wire harness including the covered electric wire 20 having the flat electric wire conductor 10 and suppressing the space required for the wiring harness arrangement, it is possible to secure a wide living space. Become.

The wire harness according to the present embodiment may be used as a wiring material for any application in an automobile, but as a suitable application, an application as a power supply trunk line placed under the floor can be exemplified. Conventionally, a general power supply trunk line for automobiles is configured by attaching an insulating sheet to an arrangement of copper plates, but it is difficult to continuously form a large copper plate, and productivity is poor. In addition, because it is made of a continuous metal, it may lead to fatigue failure of the material due to the effects of automobile engine vibration. On the other hand, if a power supply main line is comprised using the wire harness of this embodiment, shaping | molding of the strand 1 which comprises the electric wire conductor 10, the twist of the strand 1, and the raw material strand 10 'obtained by twisting together Any of forming into a flat shape is a process that can be continuously performed on each part of the long material, and high productivity can be achieved. Moreover, since the electric wire conductor 10 consists of the assembly | assembly of the thin strand 1, the electric wire conductor 10 as a whole has high tolerance with respect to bending and vibration. Therefore, fatigue failure due to engine vibration or the like hardly occurs.

Moreover, the form which forms not only the form which arranges the wire harness concerning this embodiment along the floor under a car etc. but the floor and ceiling itself with the wire harness concerning this embodiment can be mentioned. In an automobile, it is necessary to route a wire harness so as not to interfere with parts such as an engine, but such a routing route is limited. In particular, in vehicles that require a large current, such as hybrid vehicles and electric vehicles, it is necessary to route wires with a large conductor cross-sectional area, and wire harnesses that include such large-cross-section wire conductors are routed. There are a limited number of possible routes. However, by constructing the floor and ceiling with the wire harness according to this embodiment, it is possible to secure a routing route by using space without waste, and also to secure a wide living space, saving space and increasing current. It is possible to satisfy both of the demands associated with. In addition, in a large-current covered electric wire, the insulator is likely to deteriorate due to the heat generated by the electric wire conductor, but disposing the wire harness as a floor or a ceiling makes it easy to ensure heat dissipation. As a result, even if the insulated wire 20 is configured using an inexpensive insulator 21 that is not so heat resistant, deterioration of the insulator 21 is less likely to be a problem. Furthermore, the covered electric wire 20 provided with the flat electric wire conductor 10 has a flat surface, and when the wire harness is configured, by arranging the covered electric wire 20 in various ways, the combination of the flat surfaces is possible. A floor or ceiling having an arbitrary surface shape can be configured. In addition, when configuring a floor or a ceiling using the wire harness according to the present embodiment, by appropriately providing a covering material on the outside of the wire harness, the wire harness is not directly exposed to the ceiling surface or the floor surface. Can do.

Furthermore, when the wire harness according to the present embodiment is arranged on the ceiling or floor of an automobile, as shown in FIG. 6, the conductor cross-sectional areas of the plurality of covered electric wires 20 constituting the wire harness are individually different. It is preferable that the heights H are aligned. By doing in this way, the upper and lower surfaces of the wire harness in the height direction can be configured in a planar manner, and when arranged along the surface of the ceiling or floor, a high space saving is achieved in the height direction. Sex can be obtained. Moreover, the uneven structure in the height direction of the wire harness is less likely to affect the design of the interior of the automobile and the function of adjacent members. Here, that the height H of the covered electric wire 20 is uniform means that the difference in the height H between the individual covered electric wires 20 is within 10% of the average height.

As shown in FIG. 6, for example, as illustrated in FIG. 6, the wire harness having the height H of the covered electric wire 20 includes an interior material 51 that constitutes a floor or a ceiling of an automobile, and an outside of the interior material 51 (the side opposite to the living space It is preferable to arrange the flat surface along the width direction x along the surfaces of the interior material 51 and the sound absorbing material 52 between the sound absorbing material 52 provided adjacent to the sound absorbing material 52. Then, the narrow space between the interior material 51 and the sound absorbing material 52 can be effectively used for the wiring harness arrangement. By arranging the height H of the covered electric wire 20, the wire harness can be arranged without unnecessarily widening the distance between the interior material 51 and the sound absorbing material 52. Moreover, the uneven structure of the height direction of a wire harness appears as the uneven structure of the surface of the interior material 51, and the situation which reduces the designability of the surface of the interior material 51 can be prevented. Furthermore, it is also possible to prevent a situation in which the performance of the sound absorbing material 52 such as nonuniformity of the sound absorbing property is affected by the coated electric wire 20 having an unevenly large height H pressing the surface of the sound absorbing material 52. As a set of the interior material 51 and the sound absorbing material 52 in which the wire harness can be disposed, a set of a floor carpet and a silencer can be exemplified.

Furthermore, the wire harness according to the present embodiment can be arranged in an automobile using various members constituting the automobile body as a support material. For example, as shown to Fig.7 (a), a wire harness can be arrange | positioned along the outer periphery of the columnar member 41 which comprises a vehicle body. Under the present circumstances, what is necessary is just to arrange | position a wire harness so that the surface along the width direction x of each covered electric wire 20 which comprises a wire harness may be along with the outer peripheral surface of the columnar member 41. FIG. Alternatively, as shown in FIG. 7B, a long member having a substantially U-shaped or substantially U-shaped cross section intersecting the longitudinal direction, that is, a hollow member having an opening 42a along the longitudinal direction. What is necessary is just to arrange | position a wire harness in the hollow part 42b of the tubular member 42. FIG. At this time, the wire harness may be formed by arranging a plurality of covered electric wires 20 in the width direction x and / or the height direction y in accordance with the shapes of the openings 42a and the hollow portions 42b. As described above, a heat radiation sheet may be appropriately disposed between the arranged covered electric wires 20. Examples of the columnar member 41 and the tubular member 42 include a member used as a reinforcement disposed in front of an instrument panel of an automobile.

(3) Combined use with other electric wires As described above, the wire harness according to the embodiment of the present invention includes the covered electric wire 20 including the flat electric wire conductor 10 according to the embodiment of the present invention, and other types of covered electric wires. Can be used in combination. The specific constituent materials, shapes, dimensions, and the like of the covered electric wire 20 according to the embodiment of the present invention and other types of covered electric wires may be any combination. Among them, as the covered electric wire 20 (first covered electric wire) according to the embodiment of the present invention, a wire provided with a flat electric wire conductor 10 made of aluminum or an aluminum alloy (aluminum-based material) is used. An electric wire (second covered electric wire) made of copper or a copper alloy (copper-based material) and having an electric wire conductor having a flatness lower than that of the electric wire conductor 10 of the first covered electric wire 20 such as a substantially circular cross section. The form to be used can be exemplified. In this case, it is preferable that the conductor cross-sectional area of the second covered electric wire is smaller than the conductor cross-sectional area of the first covered electric wire 20.

Aluminum-based materials have been used instead of copper-based materials as materials for automotive wire conductors to reduce the weight of the entire automobile. Since the electrical conductivity as a material is lower in the case of using the copper-based material, the conductor cross-sectional area of the electric wire conductor tends to be larger. If the wire conductor made of such an aluminum material is configured as a conventional conductor having a circular cross section and used in a wire harness, the space required for the wiring harness becomes large due to the increase in the diameter of the wire conductor. However, by using the flat wire conductor 10, it is possible to reduce the space required for routing while securing a large conductor cross-sectional area. On the other hand, even if it is an electric wire conductor using a copper-type material, if it is a thin wire with a small conductor cross-sectional area, it will not become a big hindrance in the weight reduction of a motor vehicle. Moreover, it is difficult to contribute to increasing the space required for the wiring harness arrangement. Therefore, the first covered electric wire 20 having the flat electric wire conductor 10 made of an aluminum material is combined with the second covered electric wire having an electric wire conductor having a substantially circular cross section made of a copper material having a smaller conductor cross-sectional area. By using it, it is possible to use the excellent characteristics of the copper-based material, such as high conductivity, as the characteristics of one part of the wire harness while ensuring space saving. As an electric wire conductor which comprises a 2nd covered electric wire, a copper alloy fine wire whose conductor cross-sectional area is 0.13 mm < ² > or smaller can be illustrated. Such a copper alloy fine wire can be suitably used as a signal wire. By making the second covered electric wire so thin, it is possible to effectively use the space saving effect by using the first covered electric wire 20 having the flat electric wire conductor 10.

Examples of the present invention are shown below. In addition, this invention is not limited by these Examples.

[Cross section of wire conductor]
With respect to the cross section of the electric wire conductor formed into a flat cross section, the state of voids and the deformation state of the strands were confirmed.

(Test method)
The aluminum alloy wire having an outer diameter of 0.32 mm 741 present twisting, to produce a substantially circular section of the material stranded conductor cross-sectional area 60 mm ^2.

The raw material stranded wire was rolled using a roller to produce a wire conductor having a substantially rectangular cross section. Rolling with a roller, as shown in FIG. 3, first applies forces F1 and F2 from the up and down direction, then applies forces F1 ′ and F2 ′ from the same direction again, and simultaneously from both sides in the width direction, This was done by applying forces F3 and F4. At this time, a sample 1 having a small compression rate (a reduction rate of the cross-sectional area) and a sample 2 having a large rolling rate were produced by varying the magnitude of the applied force. Then, the insulator of 1.5 mm in thickness which consists of PVC was coat | covered on the outer periphery of each electric wire conductor.

Each of sample 1 and sample 2 was embedded in an epoxy resin, and a cross section intersecting the axial direction was polished to prepare a cross-sectional sample. And photography was performed with respect to the obtained cross-sectional sample.

The image of the photographed cross section was analyzed and the porosity was evaluated. At this time, the cross-sectional area (A0) of the entire wire conductor is estimated as the area of the inner region of the outline connecting the outlines of the strands located on the outermost periphery of the wire conductor, and the gap area (A1) is The area was estimated as the area of the area not occupied by the strand, and the porosity was calculated (A1 / A0 × 100%).

Furthermore, the deformation rate of the wire was evaluated by image analysis. At this time, the deformation rate of the wire was estimated as shown in the above formula (1). As the circular diameter R, 0.32 mm which is the outer diameter of the raw material stranded wire before compression was adopted. Further, the deformation rate of the strands is determined by the strands included in the outer peripheral portion (end portion) shown as the square region R1 in FIGS. 8B and 8C and the central portion similarly shown as the square region R2. The average value of the deformation rate in each region was calculated. Furthermore, the ratio of the outer peripheral deformation rate was calculated as the ratio of the outer peripheral deformation rate to the central deformation rate (outer peripheral deformation rate / central deformation rate × 100%).

(Test results)
FIG. 8 shows a photograph taken with respect to a cross section of the covered electric wire. (A) corresponds to the raw material stranded wire before compression, (b) corresponds to the sample 1 having a low compression rate, and (c) corresponds to the sample 2 having a high compression rate. Table 1 below summarizes the porosity and deformation rate values obtained by image analysis for Sample 1 and Sample 2.

 

Comparing the cross-sectional photographs of sample 1 and sample 2 in FIGS. 8B and 8C, sample 1 has relatively large voids between the strands, whereas sample 2 has a relatively large gap. The wire is in a tightly packed state. Further, in the sample 1, the cross section of each strand is not greatly deformed from the substantially circular shape before rolling in FIG. 8A, whereas in the sample 2, the element is largely deformed from the circle. There are many lines. In particular, paying attention to the width direction end of the wire conductor, in Sample 1, the end is smoothly formed, whereas in Sample 2, as shown by the circle, sharp burrs are generated. ing.

These trends seen in the photographs are clearly shown in the image analysis results in Table 1. First, the porosity of the cross section of the wire conductor is 30% for Sample 1 and 16% for Sample 2, and is about twice that of Sample 2 for Sample 1. Furthermore, in the sample 1, there are many continuous voids that can accommodate two or more strands as shown by arrows in FIG. 8B, whereas the sample in FIG. 2 shows almost no such large continuous voids.

Next, with respect to the deformation rate of the wire, the deformation rate of the central portion of the wire conductor is the same in the sample 1 and the sample 2. However, the deformation rate of the outer peripheral portion is greatly different between Sample 1 and Sample 2. In Sample 1, the deformation rate of the outer peripheral portion is smaller than the deformation rate of the central portion, and is suppressed to 18% of the value of the central portion. On the other hand, in the sample 2, the deformation rate of the outer peripheral portion is the same as the deformation rate of the central portion.

From the above results, by suppressing the compression rate when rolling the raw material stranded wire, it has a large porosity, and the deformation rate of the outer peripheral strand is smaller than that of the central portion, and the cross section is flat. It was confirmed that an electric wire conductor could be obtained.

[Flexibility of coated wire]
The influence of the cross-sectional shape of the wire conductor on the flexibility of the covered wire was confirmed.

(Test method)
In the same manner as in the test of “the state of the cross section of the wire conductor”, a wire conductor having a circular cross section and a flat cross section made of an aluminum alloy was produced. Further, an insulating coating was provided in the same manner as described above to produce a covered electric wire. The conductor cross-sectional areas of the wire conductors were ^two types, 35 mm ² and 130 mm ² . The aspect ratio of the flat cross-sectional shape was 1: 3 when the conductor cross-sectional area was 35 mm ² and 1: 4 when the conductor cross-sectional area was 130 mm ² .

The flexibility was evaluated by measuring the repulsive force for each of the coated electric wires produced. The repulsive force was measured by a three-point bending method. That is, the repulsive force when the both ends of the coated wire having a length of 100 mm were gripped and the center portion was bent was measured with the load cell.

(Test results)
Table 2 below shows the measurement results of the repulsive force obtained for each coated electric wire.

 

According to Table 2, the repulsive force is reduced by changing the cross-sectional shape from a circular shape to a flat shape in any conductor cross-sectional area. In other words, flexibility is high. Even when the conductor cross-sectional area is large such as 130 mm ² , flexibility can be improved by flattening. In any conductor cross-sectional area, the repulsive force is reduced to 90% or less by flattening. However, in order to achieve the same degree of flexibility improvement when the conductor cross-sectional area is large, It is necessary to increase the aspect ratio (increase the width).

[Heat dissipation of coated wire]
The relationship between the heat dissipation of the covered wire, the shape of the wire conductor, and the presence or absence of the heat dissipation sheet was confirmed by computer simulation.

(Test method)
By computer simulation using heat conduction analysis by the finite element method, the degree of temperature rise when energizing the coated wire was estimated. Specifically, a 1.6 mm thick insulation coating made of PVC is formed on the outer periphery of three types of copper conductors having a circular cross section, a flat shape with an aspect ratio of 1: 3, and a flat shape with an aspect ratio of 1: 5. The covered electric wire formed with was assumed as a sample. The cross-sectional area of the conductor was 134.5 mm ^{2 in} the case of a circular cross section, and was changed in three ways on the basis of the value in the case of a flat cross section. And the temperature rise at the time of reaching a steady state by supplying a current of 400 A to each sample was estimated by simulation. The temperature of the surrounding environment was 40 ° C.

Moreover, the temperature rise was similarly estimated also about the case where a thermal radiation sheet was provided with respect to the covered electric wire which has a flat-shaped electric wire conductor whose aspect ratio is 1: 5. As the heat dissipation sheet, two types of aluminum plates having a thickness of 5 mm and a width of 30 mm and 60 mm were used. The center of the width direction x of the covered electric wire was aligned with the center of the width direction of the heat radiating sheet, and the flat surface along the width direction x of the covered electric wire was placed in close contact with the surface on one side of the heat radiating sheet.

(Test results)
FIG. 9 shows temperature rise values obtained by simulation for each sample as a function of conductor cross-sectional area. FIG. 9 also shows an approximate curve.

According to FIG. 9, the temperature rise is suppressed to be lower in the case of the flat cross section than in the case of the circular cross section of the electric wire conductor. That is, heat dissipation is improved. In particular, the heat dissipation is enhanced as the aspect ratio of the flat shape is increased (the width is increased). As a result, when the upper limit of the temperature rise is set to a predetermined temperature value, even if the conductor cross-sectional area of the wire conductor is reduced by making the wire conductor flat in cross section and further increasing the aspect ratio, It becomes possible to suppress the temperature rise within the range. For example, when the upper limit value of the temperature rise is 40 ° C., the lower limit value of the conductor cross-sectional area is about 135 mm ² when the cross section is circular, and about 125 mm ² when the flat shape has an aspect ratio of 1: 3. In the case of a flat shape with an aspect ratio of 1: 5, it is about 120 mm ² .

Furthermore, if a heat dissipation sheet is provided on a covered electric wire having a flat cross-section electric wire conductor, the heat dissipation is further enhanced. Especially, heat dissipation is so high that the cross-sectional area of a thermal radiation sheet is large. In other words, when the upper limit of the temperature rise is set to a predetermined temperature value, even if the conductor cross-sectional area of the electric wire conductor is reduced by using a heat radiating sheet having a large cross-sectional area, the temperature rise is suppressed within the upper limit range. It becomes possible. For example, when the upper limit value of the temperature rise is 40 ° C. and the width of the heat dissipation sheet is 30 mm, the lower limit value of the conductor cross-sectional area is about 95 mm ² . At this time, the cross-sectional area of the heat dissipation sheet is about 1.6 times the conductor cross-sectional area. On the other hand, when the width of the heat dissipation sheet is 60 mm, the lower limit value of the conductor cross-sectional area is 67 mm ² . At this time, the cross-sectional area of the heat dissipation sheet is about 4.5 times the cross-sectional area of the conductor.

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

Further, in the above description, the electric wire conductor has been described with respect to a form having a porosity greater than or equal to a predetermined value. Therefore, it is also conceivable that the cross section intersecting with the axial direction of the stranded wire has a flat portion made of a flat shape. Further, even when such a configuration is adopted, the flatness of the cross-sectional shape can improve flexibility and achieve both space saving than the case where the cross-sectional shape is substantially circular. Furthermore, even in such a case, each configuration related to the wire conductor other than the porosity described above, that is, the deformation rate, the cross-sectional shape of each strand, the material and conductor cross-sectional area of the wire conductor, the aspect ratio of the wire conductor A configuration such as coexistence of the flat portion and the low flat portion can be suitably applied. Moreover, the structure regarding the covered electric wire and wire harness which were demonstrated above can also be applied suitably.

DESCRIPTION OF SYMBOLS 1 Strand 10 Electric wire conductor 10 'Raw material strand wire 20 Covered electric wire 21 Insulator H Height W Width x Width direction y Height direction 31 Heat radiation sheet 32 Interposition sheet (heat radiation sheet)
33 Connecting material 41 Columnar member 42 Tubular member 51 Interior material 52 Sound absorbing material

Claims (16)

1. It consists of stranded wires made by twisting multiple strands,
   The cross section intersecting the axial direction of the stranded wire has a flat portion made of a flat shape,
   A wire conductor characterized in that, in the cross section of the flat portion, a void ratio, which is a ratio of voids not occupied by the strands, is 17% or more.
2. The wire conductor according to claim 1, wherein the porosity is 40% or less.
3. The deformation ratio from the circular shape of the wire in the cross section of the flat portion is smaller than the central portion of the flat portion at a portion facing the outer periphery of the flat portion. Wire conductor.
4. The deformation ratio from the circular shape of the strand is 50% or less of the central portion of the flat portion at a portion facing the outer periphery of the flat portion. Wire conductors.
5. 5. The deformation ratio from the circular shape of the wire in the cross section of the flat portion is 10% or less in a portion facing the outer periphery of the flat portion. 6. Wire conductors.
6. The electric wire conductor according to any one of claims 1 to 5, wherein a cross-section of the flat portion has a continuous gap that can accommodate two or more of the strands.
7. The cross section of the flat portion has opposite sides parallel to each other along the width direction of the flat shape,
   The deformation rate from the circular shape of the wire in the cross section of the flat part is smaller than the central part of the flat part at the opposite end of the flat part parallel to each other. The electric wire conductor according to any one of 6.
8. The electric wire conductor according to any one of claims 1 to 7, wherein the electric wire conductor includes the flat portion and a low flat portion having a flatness lower than that of the flat portion in the axial direction.
9. The wire conductor according to any one of claims 1 to 8, wherein the number of strands constituting the stranded wire is 50 or more.
10. The wire conductor according to any one of claims 1 to 9,
    An insulated wire covering an outer periphery of the wire conductor.
11. A wire harness comprising the coated electric wire according to claim 10.
12. A plurality of the covered electric wires according to claim 10, wherein the plurality of covered electric wires are arranged along at least one of the width direction of the electric wire conductor and a height direction intersecting the width direction,
    12. The wire harness according to claim 11, comprising at least one of a heat dissipation sheet interposed between the plurality of covered electric wires and a heat dissipation sheet that contacts the plurality of covered electric wires in common.
13. The wire harness according to claim 12, comprising a plurality of the covered electric wires according to claim 10, wherein the plurality of covered electric wires are arranged at least along the height direction.
14. Between the plurality of covered electric wires arranged along the height direction, intervening sheets made of a heat dissipating material are interposed, and a plurality of the interposing sheets are connected to each other to connect the heat dissipating material. The wire harness according to claim 13, wherein a material is provided.
15. The wire harness includes a first covered electric wire and a second covered electric wire,
    The first covered electric wire is a covered electric wire according to claim 10, wherein the electric wire conductor is made of aluminum or an aluminum alloy.
    The wire conductor of the second covered electric wire is made of copper or a copper alloy, has a flatness lower than that of the electric wire conductor of the first covered electric wire, and has a small conductor cross-sectional area. The wire harness according to any one of 14.
16. The wire harness according to claim 15, wherein a conductor cross-sectional area of the second covered electric wire is 0.13 mm ² or less.

Images