Electromagnetic shielding structure

Abstract

To provide an electromagnetic shield structure, etc. with high waterproof properties.SOLUTION: One braided wire 1 is inserted inside one rigid tube 3 without being cut in the middle. The length of the braided wire 1 is longer than the length of the rigid tube 3. Therefore, end portions of the braided wire 1 protrude a predetermined length from both ends of the rigid tube 3. Wires 7 are arranged in the inside of the rigid tube 3 and the braided wire 1. An impregnant is coated to the braided wire 1 in a predetermined range from the end portions of the rigid tube and the impregnant is impregnated into a gap between the braided wire 1 and wires 7 to cure the impregnant. A resin member 11 is arranged around the perimeter of the braided wire 1 to cover the range where the impregnant 9 is impregnated.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an electromagnetic shield structure or the like, in which electric wires are passed through, and which is used, for example, in an electric vehicle. [Background technology]

[0002] Electric vehicles such as BEVs (Battery Electric Vehicles) and HEVs (Hybrid Electric Vehicles) use wire harnesses that run under the floor. These wire harnesses, like conventional wire harnesses, use corrugated tubes, protectors, and rigid pipe-shaped exterior materials.

[0003] On the other hand, underfloor wiring harnesses, which are required to transmit large amounts of power, require noise shielding measures to prevent noise from affecting auxiliary equipment and passengers on the vehicle.

[0004] Such an electromagnetic shielding structure uses an electromagnetic shielding tube made of a metal pipe, the end of which is covered with, for example, a cylindrical braided wire. By crimping the electromagnetic shielding tube and the braided wire from the outside with a crimping member, electrical continuity between the electromagnetic shielding tube and the braided wire can be established and the braided wire can be connected to the electromagnetic shielding tube (for example, Patent Documents 1 to 3). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2017-117863 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-120917 [Patent Document 3] Japanese Patent Application Laid-Open No. 2004-171952 Summary of the Invention [Problem to be solved by the invention]

[0006] As in Patent Documents 1 to 3, by using a braided wire, it is possible to cover with a conductor the electric wire inserted inside the metal electromagnetic shielding tube and the connection part with other electric equipment units, etc., thereby ensuring the shielding properties of the connection part. In addition, because the braided wire is flexible, it is possible to ensure the shielding properties between the electromagnetic shielding tube and the electric equipment units, etc.

[0007] On the other hand, when waterproofing such electromagnetic shielding structures, grommets are usually used. Grommets are attached to the end of the shielding pipe to prevent water from entering near the connection of the braided wire. However, if the internal electric wires move axially relative to the shielding pipe, water may enter the inside of the shielding pipe along with the electric wires. Furthermore, if water enters a harness in an engine room (motor room), for example, water may be siphoned up between the electric wires, between the individual wires of the braided wire, or between the electric wire and the braided wire.

[0008] The present invention has been made in view of the above problems, and has as its object to provide an electromagnetic shielding structure and the like that is highly waterproof. [Means for solving the problem]

[0009] In order to achieve the above-mentioned objectives, 1 The invention is an electromagnetic shielding structure comprising a rigid tube having a predetermined rigidity and capable of retaining its shape, a braided wire extending from at least an end of the rigid tube, and an electric wire disposed inside the braided wire, wherein the rigid tube is bent, an impregnating agent is impregnated into gaps in the braided wire within a predetermined range from the end of the rigid tube, and a compressible, elastically deformable resin member is disposed around the outer periphery of the braided wire so as to cover the range impregnated with the impregnating agent. No. 2The invention is an electromagnetic shielding structure comprising a rigid tube having a predetermined rigidity and capable of retaining its shape, a braided wire extending from at least an end of the rigid tube, and an electric wire disposed inside the braided wire, wherein the rigid tube is made of metal, an impregnating agent is impregnated into gaps in the braided wire within a predetermined range from the end of the rigid tube, and a compressible, elastically deformable resin member is disposed on the outer periphery of the braided wire so as to cover the range impregnated with the impregnating agent.

[0010] It is desirable that the rigid tube be a resin tube, the braided wire be inserted through the rigid tube, and an end of the braided wire protrude from an end of the rigid tube. It is desirable that the rigid tube be divided into a plurality of sections, and that the impregnating material and the resin member be disposed at a portion where the braided wire inside the rigid tube is exposed from the rigid tube. It is desirable that a grommet be disposed so as to cover the boundary between the rigid tube and the braided wire.

[0011] The grommet may be taped to the rigid tube or the braided wire.

[0012] The resin member may be a sheet member of butyl rubber or a sheet member of closed-cell foam, and the sheet member may be wrapped around an outer periphery of the braided wire.

[0013] It is desirable that the resin member be a sheet member made of butyl rubber and have an outer diameter formed in a substantially circular shape. It is desirable that the grommet be disposed so as to cover at least the end of the rigid pipe and a part of the resin member, and be capable of suppressing the intrusion of water between the grommet and the resin member.

[0014] According to the first aspect of the present invention, the impregnating agent prevents water from being absorbed between the wires of the braided wire or through gaps in the wire, and the outer resin member prevents water from seeping in through gaps between the wire and the rigid tube, for example, resulting in high waterproof performance.

[0015] Furthermore, by providing grommets, it is possible to more reliably prevent water from entering from the outside.

[0016] Furthermore, by fixing the grommet to the rigid tube or the braided wire, it is possible to reliably prevent the grommet and the wire from shifting.

[0017] Furthermore, the resin member is a sheet member made of butyl rubber or closed-cell foam, and by wrapping the sheet member, gaps around the outer periphery of the braided wire and the electric wire can be easily filled, ensuring waterproofing.

[0018] Furthermore, by passing a single braided wire through a rigid resin pipe, there is no need to connect the braided wire at the end of the rigid pipe. This eliminates the need for connection work and crimping members. Furthermore, because no electrical connection between the pipe and the braided wire is required, there is no risk of a decrease in shielding performance at the connection, and highly reliable shielding performance can be obtained throughout the entire pipe.

[0019] Furthermore, since the rigid pipe itself does not require shielding properties, there is no need to use an electromagnetically shielded pipe such as a metal pipe or a composite pipe in which a metal layer and a resin layer are integrated. Furthermore, since no metal is exposed on the outside of the rigid pipe, there is no need for an exterior to protect the metal part. [Effects of the Invention]

[0022] According to the present invention, it is possible to provide a highly waterproof electromagnetic shield structure and the like. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 2 is an exploded perspective view of the braided wire 1 and the rigid tube 3. [Figure 2] FIG. 2 is a diagram showing a state in which the braided wire 1 is inserted into the rigid tube 3. [Figure 3] 4A and 4B are diagrams showing the construction process of an electromagnetic shield structure, in which (a) is an enlarged view of the vicinity of the end of the rigid pipe 3, and (b) is a cross-sectional view taken along line AA in (a). [Figure 4] 5A and 5B are diagrams showing the construction process of an electromagnetic shield structure, in which (a) is an enlarged view of the vicinity of the end of the rigid pipe 3, and (b) is a cross-sectional view taken along line BB in (a). [Figure 5]10(a) is an enlarged view of the vicinity of the end of the rigid tube 3 of the electromagnetic shielding structure 5, and FIG. 10(b) is a cross-sectional view taken along line CC of FIG. [Figure 6] 1(a) is an enlarged view of the vicinity of the end of the rigid tube 3 of the electromagnetic shield structure 5a, and FIG. 1(b) is an enlarged view of the vicinity of the end of the rigid tube 3 of the electromagnetic shield structure 5b. [Figure 7] 10(a) and 10(b) are enlarged views of the vicinity of the end of the rigid pipe 3, illustrating another construction process for the electromagnetic shield structure. [Figure 8] 10(a) is an enlarged view of the vicinity of the end of the rigid pipe 3 showing another construction process of the electromagnetic shield structure, and FIG. 10(b) is an enlarged view of the vicinity of the end of the rigid pipe 3 of the electromagnetic shield structure 5c. [Figure 9] 10A is an enlarged view of the vicinity of the end of the rigid tube 3 of the electromagnetic shield structure 5d, and FIG. 10B is an enlarged view of the vicinity of the end of the rigid tube 3 of the electromagnetic shield structure 5e. DETAILED DESCRIPTION OF THE INVENTION

[0024] An electromagnetic shield structure according to an embodiment of the present invention will now be described. Fig. 1 is an exploded perspective view of the electromagnetic shield structure before construction, and Fig. 2 is a perspective view showing a state in which a braided wire 1 is inserted into a rigid tube 3.

[0025] The braided wire 1 is a flexible cylindrical member in which metal wires are woven. Note that the braided wire 1 does not have to be entirely made of metal wires, and may be made of metal wires and resin wires woven together as long as the desired shielding performance is ensured.

[0026] The rigid pipe 3 may be made of metal, but a resin pipe is also applicable. The rigid pipe 3 is molded into a shape that corresponds to the installation location in, for example, a vehicle. The rigid pipe 3 only needs to have a predetermined rigidity that prevents the shape from changing due to its own weight, etc., and can tolerate some bending due to external forces as long as the shape is maintained during use.

[0027] If the rigid tube 3 is made of resin, it may be cross-linked to improve heat resistance, or may contain a flame retardant such as a halogen-based, phosphorus-based, or metal hydrate, or may contain titanium oxide to improve weather resistance. If necessary, the resin may be colored.

[0028] As shown in FIG. 2, one braided wire 1 is inserted into one rigid tube 3 without being cut along the way. The length of the braided wire 1 is longer than the length of the rigid tube 3. Therefore, the ends of the braided wire 1 protrude a predetermined length from both ends of the rigid tube 3. In other words, the braided wire 1 extends from at least the ends of the rigid tube 3. An electric wire is inserted through the rigid tube 3 and the braided wire 1 to form an electromagnetic shielding structure. Note that the total length of the braided wire 1 exposed from the rigid tube 3 is shorter than the total length of the rigid tube 3.

[0029] Next, a method for further improving the waterproofing of the electromagnetic shield structure described above will be described. Figures 3 to 5 are diagrams showing the steps of the construction method for the electromagnetic shield structure, with Figure 3(a) being an enlarged view of the vicinity of the end of the rigid tube 3 and Figure 3(b) being a cross-sectional view taken along line AA in Figure 3(a). As shown in Figures 3(a) and 3(b), electric wires 7 are inserted and disposed inside the rigid tube 3 and the braided wire 1. In the illustrated example, three electric wires 7 are inserted, but the number of electric wires 7 may be one or more. For example, a high-voltage electric wire can be used as the electric wire 7.

[0030] Next, an impregnating agent is applied to the braided wire 1 within a predetermined range from the end of the rigid tube, and the impregnating agent is allowed to penetrate into the gaps in the braided wire 1 (for example, between the wires constituting the braided wire 1, between the braided wire 1 and the electric wire 7, and between the electric wires 7 if there are multiple electric wires 7) and then hardened. FIG. 4(a) is a conceptual diagram showing the state after the impregnating agent 9 has been applied and impregnated, and FIG. 4(b) is a conceptual cross-sectional view of line BB in FIG. 4(a). The impregnating agent 9 can be a silicone material or a low-viscosity adhesive (for example, a volatile adhesive or epoxy). By applying the impregnating agent 9 from the outer periphery of the braided wire 1 and then kneading the braided wire 1, for example, the impregnating agent 9 can penetrate into the gaps between the wires of the braided wire 1, the gaps between the electric wires 7, and the gaps between the electric wire 7 and the braided wire 1. While the impregnating agent 9 is preferably a curing agent, it need not be hardened if it does not leak out.

[0031] FIG. 5(a) is a conceptual diagram showing a state in which a resin member 11 is arranged so as to cover the area impregnated with the impregnating agent 9, and FIG. 5(b) is a conceptual cross-sectional view taken along line CC in FIG. 5(a). The resin member 11 is arranged on the outer periphery of the braided wire 1 so as to cover the area impregnated with the impregnating agent 9. The resin member 11 is compressively elastically deformable, and can be made of, for example, butyl rubber or a closed-cell resin foam. Note that a cylindrical resin member 11 may be used as the covering, or a sheet member may be wrapped around it. Because the resin member 11 has cushioning properties, compressive elastic deformation of the resin member 11 covers any irregularities in the outer shape caused by the electric wire 7, etc. Furthermore, the outer shape of the arranged resin member 11 can be formed into a substantially circular shape.

[0032] It is desirable that the resin member 11 covers the entire area where the impregnating agent 9 is applied. In other words, it is desirable that the length of the resin member 11 from the end of the rigid tube 3 is longer than the area impregnated with the impregnating agent 9. The resin member 11 may be fixed by adhesive or the like, or a part of the wrapped resin member 11 may be inserted into the inside of the rigid tube 3 and fixed.

[0033] In this way, the electromagnetic shield structure 5 is formed. According to the electromagnetic shield structure 5, even if water seeps in from the tip side of the formed waterproof structure, the gaps between the wires of the braided wire 1 and the electric wires 7 are sealed with the impregnating agent 9, so that the water does not seep through the gaps and enter the inside of the rigid tube 3 by being sucked up, etc. Furthermore, larger gaps, such as those between the electric wires 7 and the rigid tube 3, are sealed with the resin member 11, so that the penetration of water into the inside of the rigid tube 3 can be more reliably suppressed.

[0034] Furthermore, by making the length of the resin member 11 longer than the impregnation length of the impregnating agent 9, it is possible to reduce the amount of the impregnating agent 9 used and more reliably protect the impregnating agent 9 (especially the end portion) when a bending force is applied to the electric wire 7. This makes it possible to prevent cracks or fissures in the impregnating agent 9 from forming a path for water penetration.

[0035] The above-mentioned waterproof structure may be formed on both ends or at least one side of the rigid tube 3. Furthermore, when the rigid tube 3 is divided into multiple sections as the entire electromagnetic shielding structure, the above-mentioned waterproof structure may be formed at any of the sections where the internal braided wire 1 is exposed from the rigid tube 3.

[0036] Although high waterproofing can be ensured even with the electromagnetic shield structure 5, a grommet may be further attached. FIG. 6(a) is a diagram showing an electromagnetic shield structure 5a in which a grommet 13 is further arranged in addition to the above-described electromagnetic shield structure 5. The grommet 13 is arranged so as to cover the boundary between the rigid tube 3 and the braided wire 1. For example, the grommet 13 is arranged so as to cover at least the end of the rigid tube 3 and a part of the resin member 11. Note that even if an armor tube is further provided outside the rigid tube 3, the grommet 13 is arranged in a position that covers the vicinity of the end of the rigid tube 3 from the outside of the armor tube.

[0037] The electromagnetic shield structure 5a, in contrast to the electromagnetic shield structure 5 described above, can further prevent water from entering the inside of the rigid pipe 3 from the outer periphery.

[0038] FIG. 6(b) is a diagram showing an electromagnetic shield structure 5b in which a grommet 13 is further fixed to the electromagnetic shield structure 5a with tape 15. Tape 15 is wrapped around from the end of grommet 13 to the outer periphery of braided wire 1, thereby fixing grommet 13 to braided wire 1. That is, tape 15 is arranged so as to cover the end of grommet 13, resin member 11, and part of braided wire 1. Note that tape 15 should be flexible and waterproof, but it is more preferable that it be a heat-resistant tape that can withstand the heat of an engine compartment, etc.

[0039] The electromagnetic shield structure 5b, compared to the electromagnetic shield structure 5a described above, further suppresses displacement of the grommet 13 and prevents water from entering the rigid tube 3. It also suppresses displacement of the braided wire 1 and the electric wires 7 relative to the rigid tube 3. Note that when suppressing displacement of only the grommet 13, the tape 15 may be disposed on the rear end side of the grommet 13. In other words, the grommet 13 only needs to be fixed to at least either the rigid tube 3 or the braided wire 1 with the tape 15.

[0040] As described above, according to this embodiment, by impregnating the gaps between the braided wire 1, the electric wire 7, etc. near the end of the rigid tube 3 with the impregnating agent 9, it is possible to suppress the uptake of water from small gaps and to suppress the infiltration of water into the rigid tube 3. Furthermore, the resin member 11 can seal gaps between the electric wire 7 and the braided wire 1 that cannot be sealed with the impregnating agent 9, such as gaps due to the uneven outer shape of the electric wire 7. This makes it possible to more reliably suppress the infiltration of water from gaps between the electric wire 7, etc.

[0041] Furthermore, by further arranging a grommet 13, it is possible to prevent water from entering from the outside of the rigid tube 3. Furthermore, by fixing the grommet 13 and the braided wire 1 with tape 15, it is possible to prevent the electric wire 7 and the braided wire 1 from shifting relative to the grommet 13.

[0042] Furthermore, because the shielding effect of the braided wire 1 is utilized over the entire length, there is no need to use an electromagnetic shielding tube such as a metal tube or a composite tube with a metal layer as the rigid tube 3. For this reason, a resin tube can be used as the rigid tube 3. Furthermore, since resin tubes are easier to bend (the tolerance for bending radius, etc. is wider) than metal tubes or composite tubes, there is a high degree of freedom in the shape of the rigid tube 3.

[0043] Furthermore, since the braided wire 1 is inserted inside the rigid tube 3, the rigid tube 3 functions as a protective tube (external sheath) for the metal wires that make up the braided wire 1. Therefore, compared to the conventional case where a metallic electromagnetic shielding tube is used, the external sheath can be reduced.

[0044] Furthermore, because the braided wire 1 can be used without cutting it, there is no need to connect the end of the braided wire 1 to the end of the rigid tube 3. For example, in the past, when connecting the braided wire 1 to the end of an electromagnetic shielding tube, a strong connection using crimping or the like was required in consideration of connection strength and electrical contact resistance, but in this embodiment, a simple fixation to prevent slippage can be used as needed. This makes the work easier and does not require the formation of protrusions such as ear clamps.

[0045] Furthermore, in conventional methods, when connecting the end of the electromagnetic shielding tube and the end of the braided wire, the end of the braided wire (the end of the metal wires that make up the braided wire) is exposed. This raises the risk of these metal wire ends damaging peripheral equipment, etc. However, in this embodiment, the end of the braided wire 1 (the metal wire end) is not exposed near the end of the rigid tube 3. This makes it possible to prevent damage to peripheral equipment, etc., caused by the end of the braided wire 1.

[0046] Furthermore, while conventionally the end of the braided wire has been folded back at the connection between the electromagnetic shielding tube and the braided wire, this folding back work is no longer necessary, and the end of the braided wire is not exposed, making the work safer.

[0047] As described above, the electromagnetic shield structure 5 can obtain a shielding effect by the braided wire 1 over almost the entire length. For example, in the past, there were discontinuous areas in the shielding effect, such as the shielding portion by the electromagnetic shielding tube, the shielding portion by the braided wire, and the junction between them, but in this embodiment, a uniform shielding effect can be obtained over the entire length. Therefore, a stable shielding effect can be obtained.

[0048] Furthermore, with conventional crimping methods, the electromagnetic shielding tube is narrowed at the connection point, and the diameter of the wire that can be inserted is determined by taking into account the inner diameter of this narrowed portion. As a result, unnecessary gaps are formed between the wire and the electromagnetic shielding tube in areas other than the connection point. However, if there is no narrowed portion, an electromagnetic shielding tube of an appropriate size for the internal wire diameter can be used in areas other than the connection point, allowing for more space-saving installation in a vehicle.

[0049] In the above-described embodiment, the braided wire 1 is inserted into the rigid tube 3, but the present invention is also applicable to a conventional electromagnetic shield structure in which a cut braided wire 1 is connected to the end of the rigid tube 3. Figures 7 to 9 are diagrams showing the configurations of other embodiments.

[0050] As shown in Figure 7(a), the end of the braided wire 1 is placed over the end of the rigid tube 3. At this time, the rigid tube 3 is, for example, a metal tube or a composite tube having a metal layer, and metal is exposed on the outer surface of the end of the rigid tube 3. In addition, an electric wire 7 is inserted through the rigid tube 3 and the braided wire 1. Note that in this embodiment as well, the braided wire 1 is assumed to extend to the end of the rigid tube 3.

[0051] Next, as shown in Fig. 7(b), the impregnating agent 9 is impregnated into at least the gaps between the braided wire 1 and the electric wire 7 within a predetermined range from the end of the rigid tube 3. At this time, as described above, it is desirable to thoroughly knead the braided wire 1, for example, to allow the impregnating agent 9 to penetrate well between the fibers and into the gaps.

[0052] 8(a), a resin member 11 is placed so as to cover the area impregnated with the impregnating agent 9. As described above, the resin member 11 may be, for example, a sheet-like material that is wrapped around the area.

[0053] 8(b), the braided wire 1 covering the rigid tube 3 is fixed with a clamp 17 to provide electrical continuity between the braided wire 1 and the metal portion of the rigid tube 3, thereby obtaining an electromagnetic shield structure 5c. Note that the clamp 17 may be fixed before the placement of the impregnating agent 9, etc.

[0054] Also in this embodiment, as shown in FIG. 9(a), an electromagnetic shield structure 5d may be formed by further arranging a grommet 13 so as to cover a part of the resin member 11 from the end of the rigid tube 3 in addition to the electromagnetic shield structure 5c.

[0055] Furthermore, in addition to the electromagnetic shield structure 5d, tape 15 may be placed around the outer periphery of the end of grommet 13 as shown in FIG. 9(b), thereby forming electromagnetic shield structure 5e in which grommet 13 is fixed with tape 15.

[0056] The electromagnetic shield structures 5c, 5d, and 5e of the present embodiment can also provide the same effects as the electromagnetic shield structures 5, 5a, and 5b.

[0057] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not limited to the above-described embodiments. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the technical ideas described in the claims, and it is understood that these modifications and alterations also fall within the technical scope of the present invention. [Explanation of symbols]

[0058] 1......braided line 3……Rigid tube 5, 5a, 5b, 5c, 5d, 5e...Electromagnetic shield structure 7……Electric wire 9...Impregnating agent 11...Resin member 13...Grommet 15...Tape 17...Clamp

Claims

1. An electromagnetic shielding structure, a rigid tube having a predetermined rigidity and capable of retaining its shape; a braided wire extending from at least an end of the rigid tube; an electric wire disposed inside the braided wire; Equipped with the rigid tube is bent; an impregnating agent is impregnated into gaps in the braided wire within a predetermined range from the end of the rigid tube, and a compressible, elastically deformable resin member is disposed on the outer periphery of the braided wire so as to cover the area impregnated with the impregnating agent.

2. An electromagnetic shielding structure, a rigid tube having a predetermined rigidity and capable of retaining its shape; a braided wire extending from at least an end of the rigid tube; an electric wire disposed inside the braided wire; Equipped with the rigid tube is made of metal; an impregnating agent is impregnated into gaps in the braided wire within a predetermined range from the end of the rigid tube, and a compressible, elastically deformable resin member is disposed on the outer periphery of the braided wire so as to cover the area impregnated with the impregnating agent.

3. 2. The electromagnetic shield structure according to claim 1, wherein the rigid tube is a resin tube, the braided wire is inserted through the rigid tube, and an end of the braided wire protrudes from an end of the rigid tube.

4. 4. The electromagnetic shield structure according to claim 1, wherein the rigid tube is divided into a plurality of sections, and the impregnating agent and the resin member are disposed in a portion where the braided wire inside the rigid tube is exposed from the rigid tube.

5. 5. The electromagnetic shield structure according to claim 1, further comprising a grommet disposed so as to cover a boundary between the rigid tube and the braided wire.

6. 6. The electromagnetic shield structure according to claim 5, wherein the grommet is fixed to the rigid tube or the braided wire with tape.

7. the resin member is a butyl rubber sheet member or a closed-cell foam sheet member, 7. The electromagnetic shield structure according to claim 1, wherein the sheet member is wrapped around an outer periphery of the braided wire.

8. 8. The electromagnetic shield structure according to claim 7, wherein the resin member is a sheet member made of butyl rubber and has an outer diameter formed in a substantially circular shape.

9. the resin member is a sheet member made of butyl rubber, and the grommet is arranged so as to cover at least an end of the rigid pipe and a part of the resin member; 6. The electromagnetic shield structure according to claim 5, wherein the intrusion of water between the grommet and the resin member can be suppressed.

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