Shielded electric wire

Abstract

A shielded electric wire includes: an electric wire; and a conductive non-woven fabric tape. The conductive non-woven fabric adhesive tape comprises a conductive non-woven fabric and a bonding layer. The adhesive layer adheres to the electric wire and adheres to the conductive non-woven fabric tape that overlaps when wound in a spiral shape. The following relation is satisfied: S / tL < = 0.5; and (S1-S2) / tL > = 0.25, where t is the width of the conductive nonwoven tape wound in the spiral shape, L is the length of the conductive nonwoven tape, S is the area of the adhesive layer in the conductive nonwoven tape, S1 is the area of an overlapping portion where the conductive nonwoven tape overlaps when the conductive nonwoven tape is wound in the spiral shape, and S2 is the area of the adhesive layer in the overlapping portion.

Description

Technical Field

[0001] The present invention relates to a shielded electric wire. Background Art

[0002] In the related art, a shielded electric wire has been proposed in which a conductive non-woven fabric having a non-woven fabric and a metal layer formed on the surface of the non-woven fabric is arranged around the periphery of the electric wire (for example, see JP2019-75375A). While the shielded electric wire exhibits an electromagnetic shielding effect due to the metal layer of the conductive non-woven fabric, it can follow the bending of the electric wire due to the relatively excellent tensile and compressive properties of the non-woven fabric. This conductive non-woven fabric is provided with an adhesive layer on one surface to form a conductive non-woven fabric tape (for example, see JP2021-140950A and JP2021-103775A), and can be attached to the periphery of the electric wire using the adhesive layer.

[0003] However, when the conductive non-woven fabric tape as described in JP2021-140950A and JP2021-103775A is attached longitudinally around the electric wire, the overlapping portion of the conductive non-woven fabric tape may separate when bent, and the shielding effect may be reduced.

[0004] Furthermore, when the conductive nonwoven tape is wound spirally, the overlapping portion also becomes spiral, making it difficult to open when bent. However, because an adhesive layer is inserted between the upper and lower conductive nonwoven fabrics in the overlapping portion, the conductive path also becomes spiral, significantly reducing the shielding effect.

[0005] To address these issues, the present applicant has developed an invention related to Japanese Patent Application No. 2022-191625. In Japanese Patent Application No. 2022-191625, a conductive nonwoven tape is spirally wound around an electrical wire. The conductive nonwoven tape includes an adhesive layer, for example, located only at one end of the conductive nonwoven fabric. When the conductive nonwoven tape is spirally wound, no adhesive layer is interposed between the overlapping portions of the conductive nonwoven fabric. Consequently, the spirally wound conductive nonwoven fabric forms a conductive path along the longitudinal direction of the electrical wire through the overlapping portions, thereby preventing a significant reduction in shielding effectiveness.

[0006] However, the conductive non-woven tape requires an adhesive layer with a width that matches the width of the overlapped portion. This means that the adhesive layer must be formed for each winding state and target wire (wire diameter, etc.), resulting in low versatility (each product is unique). In addition, when the conductive non-woven tape has an adhesive layer formed only at one end of the conductive non-woven fabric in the width direction, the conductive non-woven fabric may float away from the wire when used longitudinally, thereby reducing the shielding effect. Summary of the Invention

[0007] The present disclosure is made to solve such a problem in the related art, and an object of the present disclosure is to provide a shielded electric wire capable of improving the versatility of a conductive non-woven fabric tape and reducing the reduction in shielding effect.

[0008] According to one aspect of the present disclosure, a shielded electric wire is provided, comprising: an electric wire; and a conductive non-woven tape wound around the electric wire, wherein: the conductive non-woven tape comprises a non-woven fabric having conductivity, i.e., a conductive non-woven fabric, and an adhesive layer formed on one surface of the conductive non-woven fabric; in the conductive non-woven tape, the adhesive layer is partially formed on the conductive non-woven fabric; when the conductive non-woven tape is spirally wound around the electric wire, the adhesive layer adheres to the electric wire and also adheres to the conductive non-woven fabric. to the conductive non-woven tape that overlaps when wound in a spiral shape; and satisfies the relationship S / tL≤0.5 and (S1-S2) / tL≥0.25, wherein t is the width of the conductive non-woven tape wound in a spiral shape, L is the length of the conductive non-woven tape, S is the area of ​​the adhesive layer in the conductive non-woven tape, S1 is the area of ​​the overlapping portion where the conductive non-woven tape overlaps when the conductive non-woven tape is wound in a spiral shape, and S2 is the area of ​​the adhesive layer in the overlapping portion.

[0009] According to the present disclosure, it is possible to provide a shielded electric wire capable of increasing the versatility of a conductive non-woven fabric tape and reducing the reduction in shielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present disclosure will become more fully understood from the detailed description given hereinafter and the accompanying drawings which are given by way of illustration only and therefore do not limit the present disclosure, in which:

[0011] Figure 1 is a perspective view showing a shielded electric wire according to an embodiment of the present disclosure;

[0012] Figure 2 It shows Figure 1 A diagram of the structure of a conductive non-woven fabric tape shown, wherein (a) shows a plane on which an adhesive layer is formed, (b) shows a cross-section perpendicular to the longitudinal direction of the tape, and (c) shows a partial enlarged view of (b);

[0013] Figure 3 It is along Figure 1 a cross-sectional view taken in the longitudinal direction of the shielded electric wire shown;

[0014] Figure 4 Schematic diagrams showing how a magnetic field is generated, wherein (a) shows the state of the magnetic field in a reference example, and (b) shows the state of the magnetic field in this embodiment;

[0015] Figure 5is a table showing Examples 1 to 3 and Comparative Examples 1 to 4;

[0016] Figure 6 is a diagram showing the shielding effects of the shielded electric wires according to Example 2 and Comparative Examples 1 and 2;

[0017] Figure 7 is a table showing shielded electric wires when a conductive non-woven fabric or a conductive non-woven fabric tape is attached longitudinally;

[0018] Figure 8 is a diagram showing the shielding effect of the shielded electric wires according to longitudinal attachment examples 1, 3, and 5; and

[0019] Figure 9 1 and 2 are plan views showing conductive non-woven fabric tapes according to modified examples, wherein (a) shows a first example, (b) shows a second example, and (c) shows a third example. DETAILED DESCRIPTION

[0020] Hereinafter, the present disclosure will be described with reference to preferred embodiments. The present disclosure is not limited to the embodiments to be described below, and the embodiments may be appropriately changed without departing from the scope of the present disclosure. In the embodiments described below, there may be portions where illustration and description of a portion of the configuration are omitted, and needless to say, within the scope not inconsistent with the contents described below, known or publicly known technologies are appropriately applied to the details of the omitted technologies.

[0021] Figure 1 1 is a perspective view showing a shielded electric wire 1 according to an embodiment of the present disclosure. Figure 1 As shown, the shielded electric wire 1 according to this embodiment includes an electric wire 10 and a conductive non-woven fabric tape 20 spirally wound around the electric wire 10. Figure 1 In the shielded electric wire 1 of the illustrated embodiment, the conductive non-woven fabric tape 20 is wound in a spiral shape, but the shape is not limited to the spiral shape, and the conductive non-woven fabric tape 20 may be attached longitudinally. Figure 1 The number of the electric wire 10 is one, but the number is not limited to one, and may be two or more.

[0022] The electric wire 10 includes a conductor 11 made of, for example, copper, aluminum, or an alloy thereof, and an insulating covering 12 covering the conductor 11. Figure 1 In the illustrated embodiment, the conductor 11 of the electric wire 10 is a stranded wire obtained by twisting a plurality of electric wires, but the present invention is not limited thereto and may also be a single electric wire. Furthermore, the covering 12 is assumed to be made of polyvinyl chloride (PVC), polypropylene (PP), or polyethylene (PE), but the material is not limited thereto and may be silicone, polyurethane, nylon, or the like.

[0023] Figure 2 It shows Figure 1The structure diagram of the conductive non-woven fabric tape 20 shown in FIG. 2 is shown, wherein (a) shows a plane on which an adhesive layer is formed, (b) shows a cross section perpendicular to the longitudinal direction of the tape, and (c) shows a partial enlarged view of (b). Figure 2 (a) and Figure 2 As shown in (b), the conductive non-woven fabric tape 20 includes a conductive non-woven fabric 21 and an adhesive layer 22 provided on one surface (front or back) of the conductive non-woven fabric 21 .

[0024] like Figure 2 As shown in (c), the conductive nonwoven fabric 21 includes fibers 21a constituting the nonwoven fabric and a plated portion 21b. The nonwoven fabric is a sheet-like component formed by entanglement of the fibers 21a without being woven. Figure 2 As shown in (c), the fibers 21a of the nonwoven fabric are formed into multiple layers in the thickness direction during the manufacturing process. The fibers 21a constituting the nonwoven fabric are made of, for example, polyethylene terephthalate (PET), polypropylene, nylon, acrylic, glass fiber, carbon fiber, aramid fiber, polyarylate fiber, etc.

[0025] The plated portion 21b is a conductive metal that covers the fibers 21a that make up the nonwoven fabric. The plated portion 21b is made of, for example, copper, nickel, tin, silver, or alloys of these metals. The plated portion 21b can be formed as a single layer or multiple layers on the fibers 21a that make up the nonwoven fabric. For example, the plated portion 21b can be formed of copper (a first layer) and tin (a second layer) on the fibers 21a that make up the nonwoven fabric.

[0026] In addition, if Figure 2 (a) and Figure 2 As shown in (b), the adhesive layer 22 is partially formed on one surface of the conductive non-woven fabric 21. Figure 2 (a) and Figure 2 In the example shown in (b), the conductive non-woven tape 20 has two adhesive layers 22 formed along the longitudinal direction of the conductive non-woven tape 20. When the conductive non-woven tape 20 is divided into two equal regions in the width direction, each adhesive layer 22 is provided at one end of each divided region. The first adhesive layer 22a of the adhesive layer 22 is formed at one end of the conductive non-woven fabric 21 and extends in the longitudinal direction with a predetermined width. The second adhesive layer 22b is formed slightly closer to the center than the other end of the conductive non-woven fabric 21 and extends in the longitudinal direction with a predetermined width. As described above, the multiple adhesive layers 22 are formed into a linear shape that is continuous at least in the longitudinal direction.

[0027] Figure 3 It is along Figure 1 The cross-sectional view of the shielded wire 1 is taken in the longitudinal direction. Figure 3As shown, when the conductive non-woven fabric tape 20 is spirally wound on the electric wire 10, the adhesive layer 22 adheres to the electric wire 10 and also adheres to the conductive non-woven fabric tape 20 that is spirally wound in an overlapping manner. Figure 2 In the case of the conductive non-woven tape 20 shown, when the conductive non-woven tape 20 is wound, the first adhesive layer 22a adheres to the electric wire 10. The second adhesive layer 22b adheres to the overlapping conductive non-woven tapes 20 in the overlapping portion La where the conductive non-woven tapes 20 overlap each other. In addition, the second adhesive layer 22b is provided in a portion of the overlapping portion La and is not provided in the remaining portion. Therefore, in Figure 2 In the conductive nonwoven tape 20 shown, in the conductive portion 23 where the adhesive layer 22 is not formed, the conductive nonwoven fabrics 21 are in contact with each other and conduct electricity.

[0028] The shielded electric wire 1 according to the present embodiment has enhanced shielding performance compared to the reference example in which the adhesive layer 22 is provided on the entire conductive non-woven fabric 21 .

[0029] Figure 4 Schematic diagrams showing how a magnetic field is generated, wherein (a) shows the state of the magnetic field in the reference example, and (b) shows the state of the magnetic field in this embodiment. Figure 4 (a) and Figure 4 As shown in FIG. 1 (b), in the electric wire 10, current flows in the direction in which the conductor 11 extends. Therefore, a magnetic field MF1 (see the dotted line) is generated in a direction perpendicular to the current.

[0030] Here, in Figure 4 In the reference example shown in (a), the adhesive layer 22 is provided on the entire conductive non-woven fabric 21. Therefore, in the overlapping portion La where the conductive non-woven tape overlaps, the adhesive layer 22 is placed between the conductive non-woven fabrics 21. Therefore, the conductive non-woven tape shown in the reference example forms a spiral conductive path CP. In this case, a magnetic field MF2 (see the solid line) is generated on the conductive non-woven tape side in a direction orthogonal to the spiral direction. The magnetic field MF2 cannot offset the magnetic field MF1 generated by the current flowing through the conductor 11.

[0031] On the other hand, in the conductive non-woven fabric tape 20 according to this embodiment, as shown in FIG. Figure 3 As described above, the conductive nonwoven fabrics 21 are electrically connected to each other via the conductive portion 23 in the overlapping portion La. Figure 4 As shown in (b), the conductive non-woven tape 20 forms a conductive path CP along the longitudinal direction of the electric wire 10. Therefore, the shielded electric wire 1 according to this embodiment can generate a magnetic field MF2 (see the solid line) that cancels the magnetic field MF1 (see the dotted line) generated by the current flowing through the conductor 11.

[0032] In particular, in the shielded electric wire 1 according to the present embodiment, the ratio of the adhesive layer 22 and the conductive portion 23 is optimized, and the magnetic field MF2 that cancels the magnetic field MF1 is appropriately generated, so that the shielding effect can be optimally exerted.

[0033] Specifically, in the shielded electric wire 1 according to the present embodiment, when the width of the conductive non-woven fabric tape 20 is t (see Figure 2 (a) and Figure 2 (b)), the length of the conductive non-woven tape 20 is L (see Figure 2 (a)), and when the area of ​​the adhesive layer 22 in the conductive non-woven tape 20 is S, it satisfies

[0034] [Formula 1]

[0035] S / tL≤0.5 (1)

[0036] tL represents the total area of ​​the conductive non-woven fabric tape 20. Therefore, as shown in the formula (1), in the conductive non-woven fabric tape 20 according to this embodiment, the area ratio of the adhesive layer 22 is 50% or less.

[0037] Furthermore, in the shielded electric wire 1 according to the present embodiment, when the conductive non-woven fabric tape 20 is spirally wound around the electric wire 10, in the case where the area of ​​the overlapping portion La where the conductive non-woven fabric tapes 20 overlap each other is defined as S1, and the area of ​​the adhesive layer 22 in the overlapping portion La is defined as S2,

[0038] [Formula 2]

[0039] (S1-S2) / tL≥0.25 (2)

[0040] Here, S1-S2 is obtained by subtracting the area of ​​the adhesive layer 22 from the area of ​​the overlapping portion La, and can be said to be the area of ​​the conductive portion 23. As described above, tL represents the total area of ​​the conductive non-woven tape 20. Therefore, formula (2) represents the ratio of the conductive portion 23 in the overlapping portion La to the entire conductive non-woven tape 20. In other words, formula (2) indicates that the conduction ratio when the conductive non-woven tape 20 is spirally wound around the electric wire 10 is 25% or greater.

[0041] By satisfying the above formulas (1) and (2), the conductive non-woven fabric tape 20 according to this embodiment can be formed as follows: Figure 4 (b) shows the conductive path CP extending in the longitudinal direction of the electric wire 10. In addition, since the ratio of the adhesive layer 22 and the conductive portion 23 is also optimized, when the conductive non-woven fabric tape 20 is properly attached to the electric wire 10, the magnetic field MF1 generated by the current flowing through the conductor 11 can be easily offset by the magnetic field MF2 generated by the conductive path CP.

[0042] Here, in Figure 3 In the example shown, the conductive non-woven tape 20 is half-wrapped. However, the shielded electric wire 1 according to this embodiment is not limited to half-wrapped and can be of any type as long as equations (1) and (2) are satisfied. In particular, the shielded electric wire 1 according to this embodiment can use any conductive non-woven tape 20 as long as equations (1) and (2) are satisfied. Therefore, the conductive non-woven tape 20 is unlikely to become the same item as disclosed in Japanese Patent Application No. 2022-191625, and versatility is improved.

[0043] As described above, the spirally wound conductive non-woven tape 20 is formed by appropriately forming an adhesive layer 22 on a conductive non-woven fabric 21 having a width exceeding t, and then cutting the conductive non-woven fabric 21 longitudinally to a width of t. Furthermore, when the conductive non-woven tape 20 is used for longitudinal attachment, the conductive non-woven tape 20 can be manufactured to a width exceeding t without cutting. The method for manufacturing the conductive non-woven tape 20 is not limited thereto. For example, the spirally wound conductive non-woven tape 20 can be formed by pre-cutting the conductive non-woven fabric 21 to a width of t and then forming the adhesive layer 2 thereon.

[0044] Examples and comparative examples will be described below. Figure 5 TABLE 1 shows Examples 1 to 3 and Comparative Examples 1 to 4.

[0045] like Figure 5 As shown in FIG. 1 , the conductive non-woven fabric tape in the shielded electric wire according to Example 1 has two adhesive layers extending in the longitudinal direction. Figure 2 The two adhesive layers shown are identical, one being provided at one end of the conductive non-woven tape in the width direction, and the other being provided slightly closer to the other end of the conductive non-woven tape from the center in the width direction. Furthermore, in the conductive non-woven tape according to Example 1, the conduction ratio shown in formula (2) is 35%, and the bonding ratio shown in formula (1) is 30%. The overlap width (the width of the overlapped portion) is set to 1 / 2 of the width of one end of the conductive non-woven tape (the area of ​​the overlapped portion is 1 / 2 of the total area). The shielding resistance of this spirally wound conductive non-woven tape is 2.27 [Ω / m].

[0046] In the shielded wire shown in Example 2, the conductive nonwoven tape is the same as that in Example 1, but the width of the adhesive layer is increased. The conduction ratio shown in equation (2) is 25%, and the bonding ratio shown in equation (1) is 50%. The overlap width is set to 1 / 2 of the width at one end of the conductive nonwoven tape. The shielding resistance of this spirally wound conductive nonwoven tape is 2.29 [Ω / m].

[0047] In the shielded wire shown in Example 3, the conductive nonwoven tape is the same as that in Example 2, with a conduction ratio of 25% as shown in equation (2) and a bonding ratio of 50% as shown in equation (1). However, one adhesive layer is formed at the center of one end (one half of the width), and the other adhesive layer is formed at the center of the other end (the other half of the width). The shielding resistance of this spirally wound conductive nonwoven tape is 2.61 [Ω / m].

[0048] In the shielded wire shown in Comparative Example 1, the conductive nonwoven fabric (which does not have an adhesive layer and is not a conductive nonwoven tape) does not have an adhesive layer. Therefore, in the conductive nonwoven fabric according to Comparative Example 1, the conduction ratio expressed in equation (2) is 50%, and the bonding ratio described in equation (1) is 0%. The overlap width is set to 1 / 2 of that at one end. The shielding resistance of this spirally wound conductive nonwoven fabric is 1.52 [Ω / m].

[0049] In the shielded wire shown in Comparative Example 2, the conductive nonwoven tape is the same as that in Example 2, but the width of the adhesive layer is increased. Therefore, in Comparative Example 2, the conduction ratio shown in equation (2) is 15%, and the bonding ratio shown in equation (1) is 70%. The overlap width is set to 1 / 2 of that at one end. The shielding resistance of this spirally wound conductive nonwoven tape is 4.3 [Ω / m].

[0050] In the shielded wire shown in Comparative Example 3, the conductive nonwoven fabric (without an adhesive layer and not a conductive nonwoven tape) was the same as that in Comparative Example 1 (without an adhesive layer). In the conductive nonwoven fabric according to Comparative Example 3, the conduction ratio expressed by equation (2) was 25%, and the bonding ratio described by equation (1) was 0%. In Comparative Example 3, the overlap width was set to 1 / 4 of the width at one end. The shielding resistance of this spirally wound conductive nonwoven fabric was 1.48 [Ω / m].

[0051] In the shielded wire shown in Comparative Example 4, the conductive non-woven tape has four adhesive layers extending in the longitudinal direction. When the conductive non-woven tape is divided into four equal areas in the width direction, each of the four adhesive layers is provided on one end side of each divided area. In addition, in the conductive non-woven tape according to Comparative Example 4, the conduction ratio shown in formula (2) is 13%, and the bonding ratio described in formula (1) is 50%. The overlapping width is set to 1 / 4 of one end. The shielding resistance of this spirally wound conductive non-woven tape is 4.34 [Ω / m].

[0052] In the above, 8d coaxial wires were used as the wires set within the conductive non-woven tape. Furthermore, a double-sided tape manufactured by DIC Corporation (product number #8080) was used to form the adhesive layer. The width of the conductive non-woven tape was 20 mm. Furthermore, the grounding portion was connected by wrapping the connector around it and then tightening the tie to the conductive non-woven tape. The tightening force of the tie was in the range of 165 N to 220 N.

[0053] Figure 6 : is a graph showing the shielding effect of the shielded electric wires according to Example 2 and Comparative Examples 1 and 2. Figure 6 , the shielding effects of Examples 1 and 3 are the same as those of Example 2, and therefore are omitted from the illustration. Similarly, the shielding effect of Comparative Example 3 is the same as that of Comparative Example 1, and the shielding effect of Comparative Example 4 is the same as that of Comparative Example 2, and therefore are omitted from the illustration.

[0054] like Figure 6 As shown in FIG1 , the shielded electric wire of Comparative Example 1 exhibits the best shielding effect. This is because the conductive nonwoven fabric does not have an adhesive layer and is therefore able to appropriately form a conductive path extending in the longitudinal direction. However, in the shielded electric wire according to Comparative Example 1, since a conductive nonwoven fabric without an adhesive layer is used, the overlapping portion opens when bent, and the shielding effect as shown in FIG1 cannot be obtained. Figure 6 When a conductive nonwoven fabric without an adhesive layer is used, the position of the conductive nonwoven fabric may become unstable, and a good shielding effect may no longer be achieved after long-term use.

[0055] Furthermore, the shielded wire according to Example 2 has the second best shielding effect, second only to the shielded wire according to Comparative Example 1. This is because the shielded wire according to Example 2 satisfies the conditions of equations (1) and (2), and therefore has a shielding resistance within the range of 1.5 [Ω / m] to 4.0 [Ω / m], and can form a relatively good conductive path extending in the longitudinal direction. Furthermore, the adhesive layer adheres not only to the wire but also to the conductive non-woven tape. Therefore, the possibility of the overlapping portion opening or the position of the conductive non-woven tape shifting during bending can be reduced, making it easy to achieve a relatively good shielding effect even in situations such as bending and long-term use.

[0056] The shielded electric wire according to Comparative Example 2 has the worst shielding effect. The shielded electric wire according to Comparative Example 2 does not satisfy any of the conditions of equations (1) and (2), and the shielding resistance exceeds 4.0 [Ω / m]. Therefore, even if a conductive path extending in the longitudinal direction can be formed, it is insufficient to cancel the magnetic field, and it is difficult to say that a good shielding effect is achieved.

[0057] Figure 7 is a table showing shielded electric wires when the conductive non-woven fabric or the conductive non-woven fabric tape is attached longitudinally.

[0058] First, if Figure 7 As shown, the shielded wire according to longitudinal bonding example 1 uses a conductive nonwoven fabric without an adhesive layer as the shielding layer. Therefore, the bonding ratio shown in formula (1) is 0%. The shielding resistance of this longitudinally bonded conductive nonwoven fabric is 0.51 [Ω / m].

[0059] In the shielded wire according to Longitudinal Attachment Example 2, the conductive nonwoven tape has three adhesive layers extending in the longitudinal direction. When the conductive nonwoven tape is divided into three equal regions in the width direction, each of the three adhesive layers is provided at one end of each divided region. Furthermore, in the conductive nonwoven tape according to Longitudinal Attachment Example 1, the bonding ratio expressed in formula (1) is 30%. The shielding resistance of this conductive nonwoven tape is 0.38 [Ω / m].

[0060] In the shielded wire according to longitudinal attachment example 3, the conductive nonwoven tape was the same as that in longitudinal attachment example 2, but the width of the adhesive layer was increased, and the bonding ratio shown in formula (1) was 50%. The shielding resistance of this conductive nonwoven tape was 0.46 [Ω / m].

[0061] In the shielded electrical wire according to longitudinal attachment example 4, the conductive non-woven tape has a single adhesive layer extending in the longitudinal direction. The single adhesive layer extends from one end of the conductive non-woven tape to the other end. In the conductive non-woven tape according to longitudinal attachment example 4, the bonding ratio shown in formula (1) is 50%, and the shielding resistance of the longitudinally attached conductive non-woven tape is 0.52 [Ω / m].

[0062] In the shielded wire according to longitudinal attachment example 5, the conductive nonwoven tape was the same as that in longitudinal attachment example 3, but the width of the adhesive layer was increased, and the bonding ratio shown in formula (1) was 70%. The shielding resistance of this conductive nonwoven tape was 1.15 [Ω / m].

[0063] Figure 8 : is a diagram showing the shielding effect of the shielded electric wire according to the longitudinal attachment examples 1, 3 and 5. Figure 8 , the shielding effects of longitudinal attachment examples 2 and 4 are the same as that of longitudinal attachment example 3, so their illustration is omitted.

[0064] like Figure 8 As shown, the shielded electric wire according to Longitudinal Attachment Example 1 exhibited the best shielding effect. In this respect, the shielded electric wire according to Longitudinal Attachment Example 3 also exhibited a shielding effect as good as that according to Longitudinal Attachment Example 1. Furthermore, the shielded electric wire according to Longitudinal Attachment Example 5 had a poorer shielding effect than Longitudinal Attachment Examples 1 and 3.

[0065] It is clear that in longitudinal attachment examples 1 to 5, the conductive non-woven fabric tapes shown in longitudinal attachment examples 2 to 4 satisfy equation (1). For the conductive non-woven fabric tapes according to longitudinal attachment examples 2 to 4, equation (2) can be satisfied depending on the overlap ratio of the spiral winding (equation (2) can be satisfied depending on how the overlap portion is designed). It was found that the conductive non-woven fabric tapes shown in longitudinal attachment examples 2 to 4 can provide the same shielding effect as the conductive non-woven fabric of longitudinal attachment example 1 even when attached longitudinally, and therefore have a high degree of versatility.

[0066] In this way, according to the shielded electric wire 1 of this embodiment, the adhesive layer 22 adheres to the electric wire 10 and also adheres to the conductive non-woven tape 20 that is wound in a spiral and overlapped. Therefore, the conductive non-woven tape 20 adheres to the electric wire 10 to prevent its displacement, etc., and also adheres to the conductive non-woven tape 20 to maintain the wrapped state. In addition, when the width of the conductive non-woven tape 20 is t, the length of the conductive non-woven tape 20 is L, and the area of ​​the adhesive layer 22 in the conductive non-woven tape 20 is S, the shielded electric wire 1 satisfies formula (1). Therefore, the proportion of the adhesive layer 22 in the conductive non-woven tape 20 can be optimized. In addition, when the area of ​​the overlapping portion La is S1 and the area of ​​the adhesive layer 22 in the overlapping portion La is S2, formula (2) is satisfied. Therefore, the area (S1-S2) that ensures conduction by the conductive portion 23 in the overlapping portion La is optimized, and even when the conductive non-woven tape 20 is wound in a spiral, the conductive path CP in the longitudinal direction is ensured. In particular, the conductive non-woven tape 20 is not limited to one having the adhesive layer 22 formed only at one end. As long as equations (1) and (2) are satisfied, its shape and other characteristics are not particularly limited, and it is unlikely to be unique. Furthermore, it can be used in a longitudinally aligned manner depending on the product. Therefore, it is possible to provide a shielded electric wire 1 that improves the versatility of the conductive non-woven tape 20 and reduces the reduction in shielding effectiveness.

[0067] Furthermore, the conductive non-woven tape 20 has a plurality of adhesive layers 22 formed continuously in a straight line at least in the longitudinal direction. Therefore, it is possible to provide a shielded electric wire 1 in which the adhesive layer 22 can be easily formed on the conductive non-woven fabric 21, and even when the conductive non-woven tape 20 is attached longitudinally, the conductive non-woven tape 20 can be properly wound around the electric wire without being easily peeled off.

[0068] Although the present disclosure has been described above based on the embodiments, the present disclosure is not limited to the above embodiments, and may be modified without departing from the gist of the present disclosure, and known or publicly known technologies may be combined.

[0069] Figure 9 1 are plan views of conductive non-woven fabric tapes showing modified examples, wherein (a) shows a first example, (b) shows a second example, and (c) shows a third example. Figure 9As shown in (a), the conductive non-woven tape 20a is not limited to the case where multiple adhesive layers 22 extend in the longitudinal direction, and can be configured to have a component extending at least in the longitudinal direction, for example, extending in an oblique direction. This also makes it easy to form the adhesive layer 22 on the conductive non-woven fabric 21, for example, by using double-sided tape. It also makes it possible to properly wrap the conductive non-woven tape 20 around the wire 10 in a state that is not easily peeled off even when the conductive non-woven tape 20 is attached in the longitudinal direction.

[0070] like Figure 9 As shown in (b), in the conductive non-woven fabric tape 20b, the adhesive layer 22 can be formed discontinuously at equal intervals in the longitudinal direction. Here, the equal intervals are not necessarily limited to the case where the adhesive layers 22 separated in the longitudinal direction are arranged at regular intervals. For example, the equal intervals include, for example, the first and second adhesive layers 22 separated in the longitudinal direction are arranged at a first interval, the second and third adhesive layers 22 separated in the longitudinal direction are arranged at a second interval, and this situation is repeated. This is because even when the adhesive layer 22 is formed discontinuously, the same effect can be obtained by satisfying formulas (1) and (2).

[0071] In addition, if Figure 9 As shown in (c), in the conductive non-woven fabric tape 20c, the conductive portion 23 may be formed discontinuously at equal intervals in the longitudinal direction. Figure 9 This is because even when the conductive portion 23 is formed discontinuously, the same effect can be obtained by satisfying the formula (1) and the formula (2).

Claims

1. A shielded electric wire, comprising: electric wire; as well as A conductive non-woven tape is wound around the wire. The conductive non-woven fabric tape comprises a conductive non-woven fabric and an adhesive layer formed on one surface of the conductive non-woven fabric. Wherein, in the conductive non-woven fabric tape, the adhesive layer is partially formed on the conductive non-woven fabric, wherein, when the conductive non-woven tape is spirally wound around the electric wire, the adhesive layer adheres to the electric wire and also adheres to the conductive non-woven tape that overlaps when spirally wound, and The following relations are satisfied: S / tL≤0.5; and (S1-S2) / tL≥0.25, Wherein, t is the width of the conductive non-woven tape wound into a spiral shape, L is the length of the conductive non-woven tape, S is the area of ​​the adhesive layer in the conductive non-woven tape, S1 is the area of ​​the overlapping portion where the conductive non-woven tape overlaps when the conductive non-woven tape is wound into a spiral shape, and S2 is the area of ​​the adhesive layer in the overlapping portion.

2. The shielded electric wire according to claim 1, in, The adhesive layer includes a plurality of adhesive layers, and In the conductive nonwoven tape, the plurality of adhesive layers are formed continuously and linearly at least in the longitudinal direction.

3. The shielded electric wire according to claim 1, in, In the conductive nonwoven fabric tape, the adhesive layer or the conductive portion where the adhesive layer is not formed is formed discontinuously at equal intervals in the longitudinal direction.

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