Wires and harnesses

Abstract

An electric wire comprising a flat stranded conductor having a flat shape in a cross-sectional view and composed of a plurality of wires each having a wire diameter of 1.2 mm or less and twisted with each other, and a flat covering portion which is an insulator and covers the flat stranded conductor. The flat covering portion has a uniform elongation of 43.5% or more.

Description

Technical Field

[0001] The present disclosure relates to electrical wires and wiring harnesses. Background Art

[0002] In the related art, with the need to expand the interior space of a vehicle, it is necessary to wire electric wires in a narrow wiring space. Here, in the case of a round electric wire, the height of the wiring space increases, and it may be difficult to perform the wiring of the round electric wire in a narrow space. Therefore, a flat electric wire may be used in which a flat conductor having a flat shape is covered with an insulator. However, when the flat conductor is formed of a single plate, the bending and vibration durability of the flat conductor is not high at all.

[0003] Therefore, a flat-shaped electric wire is proposed. The flat-shaped electric wire is obtained by pressing a round electric wire having a conductor portion composed of a plurality of conductor wires. According to the electric wire, since the conductor portion is composed of a plurality of conductor wires, the bending durability and vibration durability of the electric wire can be improved (for example, see JP-A-2018-101627).

[0004] However, the electric wire described in JP-A-2018-101627 may have cracks in the insulation covering the conductor portion of the electric wire during pressing or the like, and may not satisfy expected electric wire characteristics. Summary of the invention

[0005] The present disclosure has been made to solve the problems of such related art, and an object of the present disclosure is to provide an electric wire and a wire harness which can improve bending durability and vibration durability and reduce the possibility of cracking of an insulator covering a conductor portion of the electric wire.

[0006] An aspect of a non-limiting embodiment of the present disclosure is directed to providing an electric wire comprising: a flat stranded conductor having a flat shape in a cross-sectional view and consisting of a plurality of wires, each of which has a wire diameter of 1.2 mm or less and is twisted with each other; and a flat covering portion which is an insulator and covers the flat stranded conductor, wherein the flat covering portion has a uniform elongation of 43.5% or more.

[0007] According to the present disclosure, bending durability and vibration durability can be improved, and the possibility of cracking of the insulator can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a configuration diagram showing an example of a wiring harness including electric wires according to an embodiment of the present disclosure;

[0009] Figure 2 It is along Figure 1 A cross-sectional view taken along line AA in FIG.

[0010] Figure 3A and 3B are schematic diagrams each showing an example of a manufacturing process, wherein Figure 3A shows a manufacturing process of an electric wire according to a comparative example, Figure 3B A manufacturing process of the electric wire according to the present embodiment is shown;

[0011] Figure 4 is a first table showing examples and comparative examples;

[0012] Figure 5 is a second table showing examples and comparative examples; and

[0013] Figure 6 is a third table showing examples and comparative examples. DETAILED DESCRIPTION

[0014] Hereinafter, the present disclosure will be described according to exemplary embodiments. The present disclosure is not limited to the embodiments to be described below, and can be appropriately changed without departing from the main purpose of the present disclosure. In addition, although some configurations are not shown or described in the embodiments to be described below, it goes without saying that within the scope of the content to be described below without contradiction, known or well-known technologies are appropriately applied to the details of the omitted technologies.

[0015] Figure 1 1 is a diagram showing a configuration of an example of a wiring harness including insulated wires according to an embodiment of the present disclosure. Figure 1 As shown, the wire harness WH includes electric wires 1 and a connector C which will be described in detail below.

[0016] For example, a terminal (not shown) is crimped or otherwise connected to the electric wire 1. The terminal is accommodated in a terminal accommodating chamber of the connector C. The wiring harness WH may include an external member such as a corrugated tube (not shown) covering the periphery of the electric wire 1, or may include an electric wire of a type different from the electric wire 1. When the wiring harness WH includes another electric wire, the electric wire 1 may be wrapped with tape together with the other electric wire. The wiring harness WH may include two or more electric wires 1. The connector C is not necessary for the wiring harness WH.

[0017] like Figure 1 As shown, the electric wire 1 includes a flat electric wire portion 10 and a round electric wire portion 20 . Figure 2 It is along Figure 1 A cross-sectional view taken along line AA in FIG.

[0018] like Figure 2As shown, the flat electric wire portion 10 includes a flat stranded conductor 11 and a flat covering portion 12, which is an insulator covering the flat stranded conductor 11. The flat stranded conductor 11 is a conductor portion having a flat shape in a cross-sectional view, and is formed by stranding a plurality of wires having a wire diameter of 1.2 mm or less. In the flat stranded conductor 11, the plurality of wires are made of, for example, aluminum or its alloy. The wire is not limited to a wire made of aluminum or its alloy, and may be made of copper or its alloy, or may be a wire obtained by plating metal or fiber, as long as the wire is conductive.

[0019] Figure 1 The circular electric wire portion 20 shown includes a circular stranded conductor 21 and a circular covering portion 22 which is an insulator covering the circular stranded conductor 21. The circular stranded conductor 21 is a conductor portion having a circular shape in a cross-sectional view and is formed by stranding a plurality of wires having a wire diameter of 1.2 mm or less. Also in the circular stranded conductor 21, the plurality of wires are made of, for example, aluminum or its alloy. The wire is not limited to a wire made of aluminum or its alloy, and may be made of copper or its alloy, or may be a wire obtained by plating metal or fiber, as long as the wire is conductive.

[0020] The flat wire portion 10 in this embodiment is formed by, for example, pressing or rolling the round wire portion 20. The flat stranded conductor 11 and the round stranded conductor 21 are continuously formed in the same wire. The flat covering portion 12 and the round covering portion 22 also continuously cover the flat stranded conductor 11 and the round stranded conductor 21.

[0021] Here, in the present embodiment, the flat cover portion 12 and the circular cover portion 22 are made of a material having a uniform elongation of 43.5% or more, for example, soft polyvinyl chloride (PVC). Figure 3A and 3B is a schematic diagram showing an example of a manufacturing process, wherein Figure 3A shows a manufacturing process of an electric wire according to a comparative example, Figure 3B A manufacturing process of the electric wire 1 according to the present embodiment is shown.

[0022] like Figure 3A As shown, in the comparative example, the flat wire portion 110 is manufactured by pressing the round wire portion 120, etc. During the pressing process, a portion of the flat covering portion 112, particularly the outer peripheral portion thereof, is stretched. Therefore, when the uniform elongation of the covering portions 112 and 122 is small, the flat covering portion 112 is broken and thus torn from the outer peripheral portion, as shown in FIG. Figure 3A shown.

[0023] like Figure 3BAs shown, in this embodiment as well, the flat wire portion 10 is manufactured by pressing the round wire portion 20, etc. Here, the uniform elongation of the covering portions 12 and 22 in this embodiment is set to 43.5% or more. Therefore, even if the outer peripheral portions of the covering portions 12 and 22 are stretched during pressing, etc., the covering portions 12 and 22 can withstand the stretching and are respectively prevented from being torn from the outer peripheral portions. Therefore, as Figure 3B As shown, the flat cover portion 12 is prevented from being broken.

[0024] In addition, the diameter of each wire of the electric wire 1 in the present embodiment is preferably 1.00 mm or less. When the round electric wire portion 20 is pressed or rolled, the round electric wire portion 20 is changed to have a flat shape in such a manner that the wire inside it moves between the wires, etc. Here, when the wire diameter is 1.00 mm or less, the repulsive force of the wire during pressing, etc. is small, and the deformation of the covering portions 12 and 22 can be reduced, and the amount of reduction in the thickness of the covering portions 12 and 22 can be reduced compared to the case where the wire diameter is greater than 1.00 mm. As a result, wear resistance can be ensured, and wire breakage can be prevented.

[0025] Specifically, in the electric wire 1 according to the present embodiment, by setting the wire diameter to 1.00 mm or less, when the thickness of the circular covering portion 22 of the circular electric wire portion 20 is set to "1", the thickness of (the thinnest portion of) the flat covering portion 12 of the flat electric wire portion 10 is "0.364 (36.4%)" or more. As a result of pressing or rolling the electric wire 1 according to the present embodiment, the end of the insulator on the long axis side of the flat shape is thinner than the end on the short axis side.

[0026] Next, examples of the present disclosure and comparative examples will be described. Figure 4 is a first table showing examples and comparative examples.

[0027] First, in each of Example 1 and Comparative Example 1, aluminum wire was used, and the conductor portion was set to 50 sq (JIS). The wire diameter was 0.32 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 11.51 mm. The covering thickness at this time was 1.38 mm.

[0028] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.4%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.71 mm, and the covering thickness of the thinnest part is 1.08 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 43.5%. The insulation reduction rate is -21.7%. In Example 1, soft PVC is used for the covering part, and in Comparative Example 1, hard PVC is used for the covering part.

[0029] In each of Example 2 and Comparative Example 2, aluminum wire was used, and the conductor portion was set to 50 sq (JIS). The wire diameter was 0.52 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 11.67 mm. The covering thickness at this time was 1.41 mm.

[0030] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.1%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.82mm, and the covering thickness of the thinnest part is 0.81mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 85.1%. The insulation reduction rate is -42.6%. In Example 2, soft PVC is used for the covering part, and in Comparative Example 2, hard PVC is used for the covering part.

[0031] In each of Example 3 and Comparative Example 3, aluminum wire was used, and the conductor portion was set to 50 sq (JIS). The wire diameter was 1.00 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 12.02 mm. The covering thickness at this time was 1.43 mm.

[0032] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.3%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.97mm, and the covering thickness of the thinnest part is 0.52mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 127.3%. The insulation reduction rate is -63.6%. In Example 3, soft PVC is used for the covering part, and in Comparative Example 3, hard PVC is used for the covering part.

[0033] In each of Example 4 and Comparative Example 4, aluminum wire was used, and the conductor portion was set to 50 sq (JIS). The wire diameter was 1.20 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 12.07 mm. The covering thickness at this time was 1.43 mm.

[0034] Such a round wire portion is pressed so that the wire low height rate is about -50% (-49.9%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 6.05mm, and the covering thickness of the thinnest part is 0.42mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 141.3%. The insulation reduction rate is -70.6%. In Example 4, soft PVC is used for the covering part, and in Comparative Example 4, hard PVC is used for the covering part.

[0035] Figure 5is a second table showing examples and comparative examples.

[0036] First, in each of Example 5 and Comparative Example 5, aluminum wire was used, and the conductor portion was set to 16sq (JIS). The wire diameter was 0.32mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 7.95mm. The covering thickness at this time was 0.99mm.

[0037] Such a round wire portion is pressed so that the wire low height rate is about -50% (-49.8%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 3.99 mm, and the covering thickness of the thinnest part is 0.77 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 44.4%. The insulation reduction rate is -22.2%. In Example 5, soft PVC is used for the covering part, and in Comparative Example 5, hard PVC is used for the covering part.

[0038] In each of Example 6 and Comparative Example 6, aluminum wire was used, and the conductor portion was set to 16sq (JIS). The wire diameter was 0.52mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 8.01mm. The covering thickness at this time was 1.05mm.

[0039] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.1%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 4.00 mm, and the covering thickness of the thinnest part is 0.62 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 81.7%. The insulation reduction rate is -40.9%. In Example 6, soft PVC is used for the covering part, and in Comparative Example 6, hard PVC is used for the covering part.

[0040] In each of Example 7 and Comparative Example 7, aluminum wire was used, and the conductor portion was set to 16sq (JIS). The wire diameter was 1.00mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 8.11mm. The covering thickness at this time was 1.07mm.

[0041] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.1%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 4.05mm, and the covering thickness of the thinnest part is 0.41mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 123.4%. The insulation reduction rate is -61.7%. In Example 7, soft PVC is used for the covering part, and in Comparative Example 7, hard PVC is used for the covering part.

[0042] In each of Example 8 and Comparative Example 8, aluminum wire was used, and the conductor portion was set to 16sq (JIS). The wire diameter was 1.20mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 8.14mm. The covering thickness at this time was 1.11mm.

[0043] Such a round wire portion is pressed so that the wire low height rate is about -50% (-49.5%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 4.11 mm, and the covering thickness of the thinnest part is 0.32 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 142.3%. The insulation reduction rate is -71.2%. In Example 8, soft PVC is used for the covering part, and in Comparative Example 8, hard PVC is used for the covering part.

[0044] Figure 6 is a third table showing examples and comparative examples.

[0045] First, in each of Example 9 and Comparative Example 9, aluminum wire was used, and the conductor portion was set to 30 sq (JIS). The wire diameter was 0.32 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 10.32 mm. The covering thickness at this time was 1.28 mm.

[0046] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.1%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.14mm, and the covering thickness of the thinnest part is 0.99mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 45.3%. The insulation reduction rate is -22.7%. In Example 9, soft PVC is used for the covering part, and in Comparative Example 9, hard PVC is used for the covering part.

[0047] In each of Example 10 and Comparative Example 10, aluminum wire was used, and the conductor portion was set to 30 sq (JIS). The wire diameter was 0.52 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 10.35 mm. The covering thickness at this time was 1.29 mm.

[0048] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.4%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.13mm, and the covering thickness of the thinnest part is 0.75mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 83.7%. The insulation reduction rate is -41.9%. In Example 10, soft PVC is used for the covering part, and in Comparative Example 10, hard PVC is used for the covering part.

[0049] In each of Example 11 and Comparative Example 11, aluminum wire was used, and the conductor portion was set to 30 sq (JIS). The wire diameter was 1.00 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 10.89 mm. The covering thickness at this time was 1.29 mm.

[0050] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.9%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.31 mm, and the covering thickness of the thinnest part is 0.51 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 120.9%. The insulation reduction rate is -60.5%. In Example 11, soft PVC is used for the covering part, and in Comparative Example 11, hard PVC is used for the covering part.

[0051] In each of Example 12 and Comparative Example 12, aluminum wire was used, and the conductor portion was set to 30 sq (JIS). The wire diameter was 1.20 mm, and the final outer diameter before pressing or rolling (ie, the state of the round wire portion) was 10.86 mm. The covering thickness at this time was 1.31 mm.

[0052] Such a round wire portion is pressed so that the wire low height rate is about -50% (-50.4%) (that is, the round wire portion is pressed so that its height is about half). The outer diameter in the minor axis direction is 5.39 mm, and the covering thickness of the thinnest part is 0.39 mm. At this time, the uniform elongation of the insulator without cracking is calculated to be 140.5%. The insulation reduction rate is -70.2%. In Example 12, soft PVC is used for the covering part, and in Comparative Example 12, hard PVC is used for the covering part.

[0053] Regarding Examples 1 to 12 and Comparative Examples 1 to 12 as described above, it was visually confirmed whether the insulator was broken. In addition, in Examples 1 to 12, the insulator was peeled off, and it was visually confirmed whether the wire was broken. In addition, a wear test (sandpaper wear test) was performed. In the sandpaper wear test, garnet P150 specified in JIS R 6251 was used as a wear belt, and the wear test was performed in accordance with the wear test (sandpaper wear) standard of ISO 6722-1 (5.12.4.1). In this test, under a normal temperature (23°C) environment, a weight of 1900g was attached to a support rod, and the wear belt was moved on the insulating covering layer (the thinnest part). Then, even if the moving distance of the wear belt is 3430mm or more, the situation where no conduction is established between the metal conductor and the wear belt is evaluated as "○", and the situation where conduction is established when the moving distance of the wear belt is less than 3430mm is evaluated as "×".

[0054] As a result of the above test, in Examples 1 to 12 using soft PVC as the insulator, the insulator was not broken. On the other hand, in Comparative Examples 1 to 12 using hard PVC as the insulator, all the insulators were broken. It can be said that the reason for this is that soft PVC satisfies the required uniform elongation of the insulator, while hard PVC does not satisfy the required uniform elongation.

[0055] Furthermore, in Examples 1 to 3, 5 to 7, 9 to 11, no wire breakage was confirmed, and the wear resistance test was evaluated as "○". On the other hand, in Examples 4, 8, and 12, wire breakage was confirmed, and the wear resistance test was evaluated as "×". That is, it was found that it is preferable to keep the insulation reduction rate at least -63.6%, as in Example 3, and, in the case where the wall pressure of the original insulation is set to "1", when the thickness of the insulation (the thinnest part) of the flat wire portion is "0.364 (36.4%)" or more, better results are obtained in terms of wire breakage and wear resistance.

[0056] Furthermore, although detailed description is omitted, it was also confirmed that the covering thickness before pressing is not particularly limited to the values ​​in Examples 1 to 12 as long as the covering thickness is within the range satisfying JASO D 618.

[0057] like Figures 4 to 6 As shown, it is also confirmed that the uniform elongation of the insulator for preventing all of the insulator from breaking is substantially unaffected by the cross-sectional area of ​​the conductor.

[0058] In the above examples and comparative examples, the wire low height rate is approximately -50%, and when the wire low height rate is approximately -50% (strictly speaking, -50.9%) or higher (when its absolute value is approximately 50% or lower), the required uniform elongation of the insulator (required uniform elongation) is smaller, so it goes without saying that rupture is further prevented.

[0059] As described above, the electric wire 1 and the wiring harness WH according to the present embodiment include the flat stranded conductor 11 having a flat cross section and formed by twisting a plurality of wires, and thus, the bending durability and the vibration durability can be improved compared to the case where the conductor portion is composed of a single plate. In addition, the uniform elongation of the flat covering portion 12 is 43.5% or more, so when the flat covering portion 12 is formed by pressing or the like, the flat covering portion 12 is easily elongated, and the possibility of the flat covering portion 12 being broken during pressing or the like can be reduced. Therefore, the bending durability and the vibration durability can be improved, and the possibility of the insulator being broken can be reduced.

[0060] In addition, the round stranded conductor 21 is formed continuously with the flat stranded conductor 11, so there is no need to join the round wire and the flat wire, and a seamless structure can be achieved. In addition, the thickness of the flat covering portion 12 is set to 36.4% or more of the thickness of the round covering portion 22, so it is possible to prevent the thickness of the flat covering portion 12 formed by pressing or rolling from being extremely thin and having a greatly reduced wear resistance.

[0061] Although the present disclosure has been described based on the embodiment, the present disclosure is not limited to the embodiment described above. Without departing from the gist of the present disclosure, the present disclosure may be appropriately modified, or known and publicly known technologies may be appropriately combined.

[0062] For example, the electric wire 1 according to the present embodiment includes the flat electric wire portion 10 and the round electric wire portion 20, but is not limited thereto, and may be composed of only the flat electric wire portion 10 by pressing the entire round electric wire portion 20, etc. In addition, in Examples 1 to 12, soft PVC is used as an insulator, but the present disclosure is not limited thereto, and soft PVC may not be used as long as the required uniform elongation can be ensured.

[0063] Here, the features of the above-described embodiments of the electric wire and the wire harness according to the present disclosure will be briefly summarized and listed in the following [1] to [3].

[0064] [1] An electric wire (1), comprising:

[0065] a flat stranded conductor (11) having a flat shape in a cross-sectional view and composed of a plurality of wires each having a wire diameter of 1.2 mm or less and twisted with each other; and

[0066] A flat covering portion (12) which is an insulator and covers the flat stranded conductor (11), wherein the flat covering portion (12) has a uniform elongation of 43.5% or more.

[0067] [2] The electric wire according to the above item [1], further comprising:

[0068] a circular stranded conductor (21) having a circular shape in a cross-sectional view and composed of a plurality of wires each having a wire diameter of 1.2 mm or less and twisted with each other; and

[0069] a circular covering portion (22) which is an insulator and covers the circular stranded conductor (21), wherein the plurality of wires of the circular stranded conductor (21) are continuously formed of the same wires as the plurality of wires of the flat stranded conductor (11),

[0070] The circular covering portion (22) is formed continuously with the flat covering portion (12), and

[0071] The thickness of the flat covering portion (12) is set to 36.4% or more of the thickness of the circular covering portion (22).

[0072] [3] A wire harness (WH), comprising:

[0073] An electric wire according to item [1] or [2] above.

Claims

1. An electric wire, comprising: a flat stranded conductor having a flat shape in a cross-sectional view and composed of a plurality of wires each having a wire diameter of 1.2 mm or less and twisted with each other; and a flat covering portion which is an insulator and covers the flat stranded conductor, The electric wire also includes a round electric wire portion, the round electric wire portion including: a round stranded conductor having a round shape in a cross-sectional view and consisting of a plurality of wires, the plurality of wires of the round stranded conductor each having a wire diameter of 1.2 mm or less and being stranded with each other; and a circular covering part which is an insulator and covers the circular stranded conductor, wherein The plurality of wires of the round stranded conductor are continuously formed of the same wire as the plurality of wires of the flat stranded conductor, The circular covering portion is formed continuously with the flat covering portion, and The thickness of the flat covering portion is set to 36.4% or more of the thickness of the circular covering portion, The flat covering portion is made of soft polyvinyl chloride having a uniform elongation of 43.5% or more, The uniform elongation is the elongation of the flat covering portion when the round electric wire portion is pressed so that the height of the round electric wire portion becomes 50%.

2. A wiring harness, comprising: The electric wire according to claim 1.

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