Wire harness and method for manufacturing wire harness

Abstract

To provide a wire harness that can reduce leakage of a resin composition constituting a waterproof portion from a sheet body and ensure high waterproofness, and a method for manufacturing the same.SOLUTION: A splice portion 5 joins electric wires 4 constituting an electric wire bundle 2 to each other in an exposed portion 21 where a conductor 41 is exposed. A waterproof portion 6 covers the splice portion and a covering portion 22 in which the exposed portion and the conductor are covered with an insulating covering 42, with a curable resin material. A sheet body 7 encloses the outer periphery of the waterproof portion. In the exposed portion, the waterproof portion fills spaces between the multiple electric wires constituting the electric wire bundle with the resin material without gaps, and along the axial direction of the electric wire bundle, when a portion of the area including the end is designated as an end region 61 and the area adjacent to the end region is designated as an adjacent region 62 in the area surrounded by the sheet body and covering the covering portion, the waterproof portion has a smoother surface in the end region than in the adjacent region.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a wire harness and a method for manufacturing the wire harness. [Background technology]

[0002] In a wire harness including a plurality of electric wires, the conductors exposed from the insulating coating of each electric wire may be joined to each other using a crimp terminal or the like to form a splice portion. Wire harnesses including such splice portions are disclosed in, for example, Patent Documents 1 to 3. In the wire harnesses including the splice portions, the portion including the splice portion may be covered with a waterproof portion made of a resin material that is difficult for water to pass through in order to protect the splice portion from contact with water. Patent Documents 1 and 2 disclose a wire harness in which a region including the splice portion is covered with a resin material to form a waterproof portion, and a sheet body is further provided to surround the outer periphery of the waterproof portion. Such a structure can be easily formed by disposing a photocurable resin composition on the surface of a light-transmitting sheet body, placing a region including the splice portion of the wire harness on the resin composition, surrounding the region with the sheet body on which the resin composition is disposed, and curing the resin composition by irradiating light from the outside of the sheet body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2012-248527 A [Patent Document 2] Patent Publication No. 2021-034188 [Patent Document 3] Japanese Patent Application Publication No. 1-154473 Summary of the Invention [Problem to be solved by the invention]

[0004] As disclosed in Patent Documents 1 and 2, if a liquid resin composition is placed on a sheet body, the sheet body is used to surround the region including the splice portion of the wire harness, and the resin composition is then cured, a waterproof portion can be easily formed around the outer periphery of the splice portion. However, in this case, in the process of folding, wrapping, etc. the sheet body on which the liquid resin composition is placed to surround the region including the splice portion of the wire harness with the sheet body, the resin composition is likely to leak out of the sheet body during these operations. If the resin composition leaks out, the workability will decrease in the subsequent process for forming the waterproof portion. In addition, if the leaked resin composition is cured as it is, the resin material cured outside the sheet body may have undesirable effects, such as contact with surrounding objects, in the completed wire harness.

[0005] If the waterproof part is made of a high-viscosity resin composition, such as the jelly-like sealant disclosed in Patent Document 3, leakage of the resin composition from the sheet body during various operation steps can be suppressed. However, when a high-viscosity resin composition is used, the resin composition may not be sufficiently distributed to each part in the area where the waterproof part should be made, including the part between the multiple electric wires joined at the splice part, and voids that are not filled by the resin material may remain inside the waterproof part. If such voids are generated, water may be allowed to enter the waterproof part, and sufficient waterproofing may not be obtained.

[0006] In view of the above, an object of the present invention is to provide a wire harness in which a waterproof portion is provided on the outer periphery of a splice portion and the outer periphery of the waterproof portion is surrounded by a sheet body, in which leakage of a resin composition constituting the waterproof portion from the sheet body is reduced and high waterproofing is ensured, and to provide a method for manufacturing such a wire harness. [Means for solving the problem]

[0007] A wire harness according to the present disclosure includes a wire bundle, a splice portion, a waterproof portion, and a sheet body, the wire bundle including a plurality of wires, the wires having a conductor and an insulating coating covering an outer periphery of the conductor, the wire bundle including an exposed portion where the conductor is exposed from the insulating coating of the wire, and a covered portion adjacent to the exposed portion where the conductor is covered with the insulating coating, the splice portion joins the wires constituting the wire bundle to each other at the exposed portion, and the waterproof portion is a portion that is connected to the splice portion and The exposed portion and the covered portion are covered with a curable resin material, the sheet body surrounds the outer periphery of the waterproof portion, and the waterproof portion fills the spaces between the multiple electric wires that make up the electric wire bundle in the exposed portion with the resin material without any gaps, and along the axial direction of the electric wire bundle, of the area surrounded by the sheet body and covering the covered portion, a portion of the area including the end is defined as an end region, and a region adjacent to the end region is defined as an adjacent region, and the end region has a smoother surface than the adjacent region.

[0008] A method for manufacturing a wire harness according to the present disclosure includes a joining step of bundling a plurality of electric wires, each having a conductor and an insulating coating covering an outer periphery of the conductor, after removing the insulating coating from a portion thereof, to form an electric wire bundle having an exposed portion where the conductor is exposed and a coated portion adjacent to the exposed portion where the conductor is covered with the insulating coating, and joining the electric wires to each other at the exposed portion to form a splice portion to produce a harness precursor; a resin disposing step of disposing a curable liquid resin composition on a portion of a surface of a sheet body; a partial viscosity increasing step of increasing the viscosity of only a portion of the resin composition disposed on the surface of the sheet body to form a high-viscosity region and leaving the other region as a liquid region; and a method for manufacturing the electric wire bundle. a harness placement step of placing a portion of the harness precursor including the splice portion on the surface of the resin composition such that the exposed portion of the harness precursor is in contact with the liquid region; a surrounding step of surrounding the harness precursor with the surface of the sheet body on which the resin composition is placed; and a curing step of curing the resin composition surrounded by the sheet body over the entire area, in this order, and in the partial viscosity increasing step, the high viscosity region is provided in a first portion and a second portion that are spaced apart from each other and include one end and the other end, respectively, along the axial direction of the harness precursor within the area in which the resin composition is placed, and the liquid region is provided between the first portion and the second portion, including an area in which the exposed portion of the wire bundle is placed. Effect of the Invention

[0009] The wire harness according to the present disclosure is a wire harness in which a waterproof portion is provided on the outer periphery of a splice portion and the outer periphery of the waterproof portion is surrounded by a sheet body, and the wire harness is capable of reducing leakage of a resin composition constituting the waterproof portion from the sheet body and ensuring high waterproofness. Moreover, the manufacturing method of the wire harness according to the present disclosure can manufacture such a wire harness. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a perspective view showing a wire harness according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing the above-mentioned wire harness. [Diagram 3] 3A to 3C are diagrams illustrating a method for manufacturing a wire harness using the partial semi-curing method. Fig. 3A shows a harness precursor obtained in a joining step, Fig. 3B shows a resin disposing step, and Fig. 3C shows a partial viscosity increasing step. In the figures, the uncured resin composition is shown with diagonal lines, and the resin material in a semi-cured state is shown with shading. [Figure 4] 4A to 4C are diagrams for explaining subsequent steps of the above-mentioned wire harness manufacturing method, in which Fig. 4A shows a harness arrangement step. Fig. 4B shows a step of folding the sheet body in the surrounding step, and Fig. 4C shows a step of narrowing the sheet body in the surrounding step. Only Fig. 4A is shown in a plan view. [Diagram 5] FIG. 5 is a diagram for explaining the subsequent steps of the above-mentioned wire harness manufacturing method, showing a curing step. [Figure 6] 6A to 6F are diagrams showing the structures of wire harnesses manufactured by three types of manufacturing methods. For wire harnesses manufactured by the partial semi-curing method, the one-step curing method, and the full area semi-curing method, respectively, Figs. 6A to 6C show an enlarged view of the state near the end of the waterproof part (cross-sectional view taken along line AA in Fig. 1), and Figs. 6D to 6F show the state of the region corresponding to the exposed part of the electric wire bundle (cross-sectional view taken along line BB in Fig. 1). [Figure 7] FIG. 7 is an enlarged photograph of the vicinity of the end of the covering of an electric wire constituting an electric wire bundle in a wire harness manufactured by the partial semi-curing method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] [Description of the embodiments of the present disclosure] First, embodiments of the present disclosure will be listed and described. (1) A wire harness according to the present disclosure includes a wire bundle, a splice portion, a waterproof portion, and a sheet body, the wire bundle including a plurality of wires, the wires having a conductor and an insulating coating covering an outer periphery of the conductor, the wire bundle including an exposed portion where the conductor is exposed from the insulating coating of the wire, and a covered portion adjacent to the exposed portion where the conductor is covered with the insulating coating, the splice portion joins the wires constituting the wire bundle to each other at the exposed portion, and the waterproof portion is a portion of the splice portion that is connected to the exposed portion of the wire bundle. the exposed portion and the covered portion are covered with a curable resin material, the sheet body surrounds the outer periphery of the waterproof portion, and the waterproof portion fills the spaces between the multiple electric wires that constitute the electric wire bundle in the exposed portion with the resin material without any gaps, and along the axial direction of the electric wire bundle, of the area surrounded by the sheet body and covering the covered portion, a portion of the area including the end is defined as an end region, and a region adjacent to the end region is defined as an adjacent region, and the end region has a smoother surface than the adjacent region.

[0012] In a wire harness having a waterproof part on the outer periphery of a splice part and further surrounded by a sheet body, the waterproof part has a smoother surface in an end region including an end part of the region surrounded by the sheet body to cover the covering part of the electric wire bundle than the adjacent region adjacent thereto. This is evidence that the leakage of the resin composition constituting the waterproof part from the sheet body is reduced in the wire harness, and the resin material is densely filled in the space between the electric wires constituting the electric wire bundle in the exposed part. The reason is as described in the next paragraph, but by reducing the leakage of the resin composition from the sheet body, the deterioration of workability due to a large amount of uncured resin composition leaking out of the sheet body during the formation of the waterproof part is suppressed. In addition, it is also difficult for the resin material that has leaked out of the sheet body and hardened to cause an effect such as contact with surrounding objects to occur. On the other hand, the resin material is densely filled in the space between the electric wires constituting the electric wire bundle, and thus the intrusion of water into the inside of the waterproof part is highly suppressed. Therefore, the waterproof part exhibits high waterproofness.

[0013] A wire harness having a waterproof part on the outer periphery of the splice part and further surrounded by a sheet body can be formed by surrounding a portion of a harness precursor having a plurality of electric wires joined at the splice part with a sheet body on which a resin composition is arranged, and then curing the resin composition. In this case, if a method is adopted in which the viscosity of a portion of the resin composition arranged on the surface of the sheet body, including both ends, is increased in advance along the axial direction of the harness precursor to form a high-viscosity region, the harness precursor is surrounded by a sheet body, and the resin composition is cured, the leakage of the resin composition constituting the waterproof part from the sheet body can be reduced as described above, and a structure in which the resin material is filled without gaps between the electric wires constituting the electric wire bundle can be easily formed. This is because the high-viscosity regions are formed at both ends, and the resin composition is less likely to flow out of the sheet body by the operation of surrounding the harness precursor with the sheet body, while the resin composition maintained at a low viscosity at the position between the high-viscosity regions can also permeate into the narrow region between the plurality of electric wires constituting the electric wire bundle. When such a manufacturing method is adopted, a part of the resin composition that has been kept at a low viscosity may flow over the high viscosity region and harden at the position where it has overcome the high viscosity region. In the high viscosity region, the resin composition hardens in a state of adhering to the sheet body, so that the fine uneven structure of the sheet body is transferred to the surface after hardening, whereas the part that has undergone the above flow hardens without adhering to the sheet body, so that it is less affected by the uneven structure of the sheet body and forms a smooth surface. Therefore, the fact that the formed waterproof part has a smoother surface than the adjacent adjacent region in the end region including the end of the region that is surrounded by the sheet body and covers the covering part of the electric wire bundle is evidence that the waterproof part has been formed by the above method of increasing the viscosity of a part of the resin composition in advance to form a high viscosity region, and functions as an indicator that the waterproof part has been formed by reducing the leakage of the resin composition outside the sheet body and has high waterproofness.

[0014] Furthermore, by having a smooth surface at the end region of the waterproof part, water is less likely to adhere or accumulate at the end of the waterproof part compared to a case where the surface has a low smoothness, and the end region plays a role in enhancing the waterproofness of the waterproof part. In addition, the smooth surface of the end region indicates that the resin material constituting the waterproof part is not strongly bonded to the sheet body in the end region. Therefore, even if a mechanical load such as bending is applied to the wire harness in the end region, peeling stress is less likely to occur between the waterproof part and the sheet body, and the waterproofness of the waterproof part is easily maintained even in a situation where a mechanical load is applied. In addition, the adhesive area between the waterproof part and the sheet body is kept small, and migration of substances through the adhesive part between the waterproof part and the sheet body is less likely to occur. As a result, even if the wire harness is used for a long time or in a high temperature environment, the resin material or the sheet body is less likely to degenerate due to migration of substances, and high waterproofness is maintained.

[0015] (2) In the above aspect (1), the waterproof part may be entirely contained within the area surrounded by the sheet body. In this case, the resin material constituting the waterproof part does not leak out of the sheet body, and the effects that may be caused by the leakage of the resin material, such as a decrease in workability when forming the waterproof part and contact between the resin material hardened outside the sheet body and surrounding objects, are eliminated.

[0016] (3) In the above-mentioned (1) or (2) aspect, the sheet body is made of a resin material containing a plasticizer, and the resin material constituting the waterproof part may contain no plasticizer or may contain a plasticizer at a lower concentration than the sheet body. When the sheet body contains a plasticizer, the sheet body can be flexibly bent and arranged on the outer periphery of the waterproof part. On the other hand, when the sheet body contains a plasticizer, the plasticizer is likely to migrate from the sheet body to the waterproof part, and if the plasticizer migrates to the waterproof part, the adhesion of the waterproof part to the electric wire and the sheet body decreases, and the waterproof property of the waterproof part may not be sufficiently maintained. However, in the wire harness of the present disclosure, as shown by the fact that the end region of the waterproof part has a smooth surface, it is not strongly adhered to the sheet body, and the adhesion area between the sheet body and the waterproof part is kept small, so that the plasticizer is unlikely to migrate from the sheet body to the waterproof part. Therefore, even if the wire harness is used for a long period of time or in a high temperature environment, the waterproof property is unlikely to decrease due to the migration of the plasticizer.

[0017] (4) In any one of the above aspects (1) to (3), the adjacent region in the waterproof portion may extend continuously at least to the region covering the splice portion, and the end region may have a smoother surface than the entire adjacent region. As described above, the adjacent region having a surface with a low smoothness is a region in which the resin composition is hardened in a state of being in close contact with the sheet body, and exerts high waterproofing due to its close contact with the sheet body. By forming such an adjacent region exerting high waterproofing, including the region covering the splice portion, the wire harness has excellent waterproofing.

[0018] (5) In the above aspect (4), the wire harness may have the splice portion as an intermediate splice portion at a midway point in the axial direction, the wire bundle as a first electric wire portion on one side of the splice portion along the axial direction, and a second electric wire portion including one or more of the electric wires on the other side, the waterproof portion covers an area extending from the covering portion of the first electric wire portion to the covering portion of the second electric wire portion, and the end region may be at least a partial area including the end portion on the first electric wire portion side. In this way, the waterproof portion can impart high waterproofness to the entire intermediate splice portion. The intermediate portion of the wire harness can be easily waterproofed by disposing a curable resin composition on the surface of a sheet body, placing a harness precursor on which an intermediate splice portion has been formed, surrounding the area including the intermediate splice portion with the sheet body, and then curing the resin composition. In this case, by forming high-viscosity areas at both ends of the resin composition along the axial direction of the harness precursor, which is evidenced by the formation of end areas with low surface smoothness, leakage of the resin composition from the sheet body can be reduced, and waterproofing of the intermediate splice portion can be easily and highly achieved. When the second electric wire portion includes only one electric wire, the end portion on the second electric wire portion side does not need to have an end portion with a smooth surface in the waterproof portion, but when the second electric wire portion is configured as an electric wire bundle including a plurality of electric wires, it is preferable to provide an end portion on the second electric wire portion side with a smooth surface, similar to the end portion on the first electric wire portion side.

[0019] (6) A method for producing a wire harness according to the present disclosure includes a joining step of bundling a plurality of electric wires, each having a conductor and an insulating coating covering an outer periphery of the conductor, after removing the insulating coating from a portion thereof, to form an electric wire bundle having an exposed portion where the conductor is exposed and a coated portion adjacent to the exposed portion where the conductor is covered with the insulating coating, and joining the electric wires to each other at the exposed portion to form a splice portion and produce a harness precursor; a resin disposing step of disposing a curable liquid resin composition on a portion of a surface of a sheet body; a partial viscosity increasing step of increasing the viscosity of only a portion of the resin composition disposed on the surface of the sheet body to form a high-viscosity region and leaving the other region as a liquid region; and The method includes a harness placement process in which a portion of the harness precursor including the splice portion is placed on the surface of the resin composition so that the exposed portion of the bundle is in contact with the liquid region; a surrounding process in which the harness precursor is surrounded by the surface of the sheet body on which the resin composition is placed; and a curing process in which the resin composition surrounded by the sheet body is cured over the entire area, in this order; and in the partial viscosity increasing process, the high viscosity region is provided in a first portion and a second portion that are spaced apart from each other and include one end and the other end, respectively, along the axial direction of the harness precursor within the area in which the resin composition is placed, and the liquid region is provided between the first portion and the second portion, including the area in which the exposed portion of the wire bundle is placed.

[0020] In this method for manufacturing a wire harness, in the partial viscosity increasing step, the viscosity of only the regions located at both ends of the axial direction of the harness precursor in the liquid resin composition placed on the surface of the sheet body is increased to form high-viscosity regions, and a liquid region where the viscosity is not increased is left between those regions. Then, in the harness placing step, the harness precursor is placed on the resin composition so that the exposed portion of the wire bundle is in contact with the liquid region, and in the surrounding step, the harness precursor is surrounded by the sheet body, and then in the curing step, the resin composition is cured over the entire region. Since the high-viscosity regions in which the viscosity of the resin composition is increased are provided at both ends of the resin composition on the sheet body, in the surrounding step, the resin material is less likely to leak out of the sheet body due to flow. This is because the resin composition in the high-viscosity regions is less likely to flow due to its high viscosity, and even if the resin composition in the liquid region flows, it is less likely to leak out of the sheet body because it is sandwiched on both sides by the high-viscosity regions. On the other hand, the resin composition in the liquid region that maintains a fluid state is in contact with the exposed portion of the electric wire bundle, so that the resin material can easily penetrate into the spaces between the electric wires in the exposed portion without leaving any gaps. As a result, after the entire resin composition is cured in the curing step, leakage of the resin material to the outside of the sheet body is reduced, and the spaces between the electric wires are filled with the resin material without any gaps in the exposed portion, so that a waterproof portion that exhibits high waterproofing can be formed. When the surrounding step is performed, the resin composition in the liquid region may remain in the region sandwiched between the high viscosity regions, or may flow beyond the high viscosity regions. In the latter case, a wire harness having the above forms (1) to (5) is obtained in which an end region having a smoother surface than the adjacent regions is formed in the waterproof portion.

[0021] (7) In the above embodiment (6), the resin composition has photocurability, the sheet body is transparent to light capable of curing the resin composition, and in the partial viscosity increase step, the resin composition is irradiated with light in a state in which the region of the resin composition arranged on the surface of the sheet body that is to be the liquid region is covered with a mask material that blocks light, thereby semi-curing the resin composition in the high-viscosity region, and in the curing step, the resin composition is irradiated with light from the outside of the sheet body that surrounds the harness precursor to cure the resin composition. In this case, by using a mask material in the viscosity increase step and irradiating light while suppressing the integrated light amount to an extent that the resin composition is not completely cured, the resin composition in the portion where the high-viscosity region is to be formed can be selectively semi-cured, and a state in which the high-viscosity region and the liquid region coexist by occupying a predetermined region can be easily formed. Furthermore, in the curing process, the integrated amount of light per area is made larger than in the viscosity increasing process, and light is irradiated from the outside of the sheet body to harden the resin material over the entire area, thereby easily forming a waterproof portion that exhibits high waterproof properties.

[0022] (8) In the above embodiment (6) or (7), the sheet body is made of a resin material containing a plasticizer, and the resin composition may contain no plasticizer or may contain a plasticizer at a lower concentration than the sheet body. In this case, the sheet body is made more flexible by containing a plasticizer, and the sheet body can be flexibly arranged around the outer periphery of a predetermined portion of the harness precursor in the surrounding step. In the manufactured wire harness, the plasticizer may migrate from the sheet body to the waterproof portion through the portion where the sheet body and the waterproof portion are firmly bonded. However, in the partial viscosity increasing step, the viscosity of the regions at both ends of the resin composition is increased and a high viscosity region is formed, so that the liquid resin composition is less likely to spread over a large area in the subsequent surrounding step. Therefore, the area of ​​the adhesive portion formed between the waterproof portion and the sheet body through the curing step is kept small, and the amount of plasticizer migrating to the waterproof portion through the adhesive portion is kept small. Therefore, in the manufactured wire harness, even after long-term use or use in a high-temperature environment, migration of the plasticizer from the sheet body to the waterproof portion is unlikely to occur, and deterioration of adhesion between the waterproof portion and the electric wires or sheet body due to migration of the plasticizer is suppressed, resulting in maintaining high waterproofness.

[0023] (9) In any one of the above (6) to (8), the harness precursor may have the splice portion as an intermediate splice portion in the axial direction, the wire bundle as a first wire portion on one side of the splice portion along the axial direction, and a second wire portion including one or more of the wires on the other side, the resin composition may be continuously disposed at a position corresponding to a region including the covering portion of the first wire portion to the covering portion of the second wire portion of the harness precursor in the resin disposing step, and the first portion may be disposed in a region corresponding to a part of the covering portion of the first wire portion and the second portion may be disposed including a region corresponding to a part of the covering portion of the second wire portion in the partial viscosity increasing step as the high viscosity region. In this case, a waterproof portion can be easily formed even in the intermediate portion of the wire harness by disposing a resin composition on a surface of a sheet body and surrounding the splice portion with the sheet body and then curing the sheet body. In the partial viscosity increasing step, a high viscosity region is provided in the resin composition, including both ends along the axial direction of the harness precursor, so that the resin composition is less likely to flow out from both ends of the sheet body in the subsequent surrounding step, thereby achieving high workability in waterproofing the intermediate splice portion.

[0024] (10) In the above aspect (9), the second wire portion may include only one electric wire, and in the partial viscosity increasing step, the second portion may be provided continuously in a region corresponding to a portion extending from the splice portion to the coating portion of the second wire portion. When the second wire portion includes only one electric wire, in order to fill the resin material between the electric wires without leaving any gaps, the portion in which the liquid region is left in the partial viscosity increasing step may be only a region on the first wire portion side from the splice portion. On the second wire portion side, a high-viscosity region may be provided continuously in a region extending from the splice portion to the coating portion of the second wire portion. In this way, by increasing the proportion of the high-viscosity region and decreasing the proportion of the liquid region, the outflow of the liquid resin composition from the sheet body can be highly suppressed.

[0025] [Details of the embodiment of the present disclosure] A wire harness and a method for manufacturing the wire harness according to an embodiment of the present disclosure will be described in detail with reference to the drawings. The wire harness according to the embodiment of the present disclosure has a splice portion where a plurality of electric wires are joined, and a waterproof portion that covers an area including the splice portion. Such a wire harness can be manufactured by the method for manufacturing the wire harness according to the embodiment of the present disclosure.

[0026] <Outline of wire harness> First, an outline of the structure of a wire harness according to an embodiment of the present disclosure will be described. An outline of a wire harness 1 according to an embodiment of the present disclosure is shown in Figs. 1 and 2. Fig. 1 is a perspective view, and Fig. 2 is a schematic cross-sectional view. Fig. 2 shows a schematic cross-section of the wire harness 1 along the axial direction, in which electric wires 4 and splice portions 5 are shown without being cut.

[0027] The wire harness 1 has a first electric wire portion 2 and a second electric wire portion 3. The first electric wire portion 2 includes a plurality of electric wires 4, and the second electric wire portion 3 includes one or a plurality of electric wires 4. In the illustrated embodiment, the first electric wire portion 2 includes three electric wires 4. The second electric wire portion 3 includes only one electric wire 4.

[0028] Each of the electric wires 4 constituting the first electric wire portion 2 and the second electric wire portion 3 has a conductor 41 and an insulating coating 42 that coats the outer circumference of the conductor 41. In each of the electric wires 4, the insulating coating 42 is removed in a partial region in the axial direction to expose the conductor 41, and the portions in the first electric wire portion 2 and the second electric wire portion 3 where the conductor 41 is exposed are the exposed portions 21 and 31, respectively. In addition, portions of the conductor 41 of each of the electric wires 4 adjacent to the exposed portions 21 and 31 where the conductor 41 is covered with the insulating coating 42 are the covered portions 22 and 32. In the wire harness 1 according to the present embodiment, one of the electric wires 4 constituting the first electric wire portion 2 (for example, the central one) is a single electric wire (main wire) that is continuous with one electric wire 4 constituting the second electric wire portion 3, and the insulating coating 42 is removed in the middle portion of the main wire to expose the conductor 41. An exposed conductor portion formed at the end of another electric wire 4 (branch wire) constituting the first electric wire portion 2 is joined to an exposed conductor portion formed in the middle of the main wire by a splice portion 5 described next.

[0029] A splice portion 5 is formed between the first electric wire portion 2 and the second electric wire portion 3. The splice portion 5 joins the electric wires 4 constituting the first electric wire portion 2 and the second electric wire portion 3 to each other at the exposed portions 21, 31. In the illustrated embodiment, the exposed conductors 41 of the electric wires 4 are joined to each other at the splice portion 5 by crimping using a crimp terminal. In the splice portion 5, the conductors 41 may be joined by any means as long as the conductors 41 of the electric wires 4 can be electrically connected to each other and physically fixed to each other. Examples of the joining may include a joining using a molten metal such as resistance welding or ultrasonic welding, or soldering, in addition to a joining using a crimp terminal. In the illustrated embodiment, the splice portion 5 is formed as an intermediate splice portion at a midway point along the axial direction of the wire harness 1. That is, the first electric wire portion 2 and the second electric wire portion 3 extend in different directions with the splice portion 5 sandwiched therebetween. The splice portion 5 joins two branch wires constituting the first electric wire portion 2 to one main wire continuing from the first electric wire portion 2 to the second electric wire portion 3 .

[0030] The wire harness 1 further has a waterproof portion 6 that covers the area including the splice portion 5 with a resin material. The resin material constituting the waterproof portion 6 covers the splice portion 5, the exposed portion 21 and the covering portion 22 of the first electric wire portion 2, and the exposed portion 31 and the covering portion 32 of the second electric wire portion 3. In other words, the waterproof portion 6 covers the entire periphery of the area extending from the covering portion 22 of the first electric wire portion 2 to the covering portion 32 of the second electric wire portion 3, continuously and seamlessly. The waterproof portion 6 serves as a waterproof material that suppresses the intrusion of water (including electrolytes; the same applies below) into the splice portion 5.

[0031] Furthermore, the wire harness 1 includes a sheet body 7. The sheet body 7 surrounds the outer periphery of the waterproof portion 6. By providing the sheet body 7 on the wire harness 1, the waterproof portion 6 can be easily formed, as will be described later in the manufacturing method of the wire harness 1. The sheet body 7 also functions as a protective member that protects the waterproof portion 6 from contact with external objects. In the illustrated embodiment, the entire waterproof portion 6 is contained inside the area surrounded by the sheet body 7. In other words, the resin material constituting the waterproof portion 6 does not leak out to the outside of the sheet body 7.

[0032] The waterproof part 6 covers the outer periphery of the region including the two electric wire parts 2, 3 and the splice part 5 in the wire harness 1. In addition, the resin material constituting the waterproof part 6 penetrates into the spaces between the components of the wire harness 1, such as the electric wire parts 2, 3 and the splice part 5, and fills these spaces. In particular, in the wire harness 1 according to the present embodiment, as shown in the cross-sectional view at the position of the exposed part 21 of the first electric wire part 2 in FIG. 6D, the waterproof part 6 fills the spaces between the electric wires 4 constituting the electric wire bundle of the first electric wire part 2 with the resin material without any gaps at least in the exposed part 21. Here, the state in which the spaces between the electric wires 4 are filled with the resin material without any gaps includes not only a state in which there is no space not occupied by the resin material, but also a state in which there are voids having a cross-sectional area of ​​approximately 10% or less of the conductor cross-sectional area of ​​each electric wire 4, and more strictly, a state in which there are voids having a cross-sectional area of ​​1% or less of the conductor cross-sectional area. Preferably, in the wire bundle of the first wire portion 2, the spaces between the wires 4 are filled without gaps with the resin material not only in the exposed portion 21 but also in the area including at least a part of the coated portion 22, and further in the entire area surrounded by the waterproof portion 6.

[0033] In the wire harness 1 according to the present embodiment, an end region 61 and an adjacent region 62 are adjacent to each other in the waterproof portion 6 along the axial direction of the first electric wire portion 2, and the end region 61 and the adjacent region 62 are distinguished from each other by the surface state. Specifically, the end region 61 is a part of a region along the axial direction of the first electric wire portion 2, including an end portion on the first electric wire portion 2 side, among the region in which the waterproof portion 6 is surrounded by the sheet body 7 to cover the first electric wire portion 2. The adjacent region 62 is provided as a region adjacent to the end region 61, and is formed as a region including a portion other than the end region 61, among the region in which the waterproof portion 6 is surrounded by the sheet body 7 to cover the first electric wire portion 2. As shown in FIG. 6A, an enlarged cross-sectional view of the vicinity of the end of the waterproof portion 6, when focusing on the surface of the waterproof portion 6 (the surface on the sheet material 7 side) from which the sheet body 7 has been removed, the waterproof portion 6 has a smoother surface in the end region 61 than the adjacent region 62. That is, the edge region 61 has a surface that is less rough, and the height difference and / or density of the surface relief structure is lower, than the adjacent region 62. The origin and characteristics of such edge region 61 will be described in detail later.

[0034] In the illustrated embodiment, the adjacent region 62 of the waterproof portion 6 extends continuously from a portion of the region covering the sheath 22 of the first electric wire portion 2, excluding the end region 61, to the region covering the splice portion 5, and further extends to the region covering the sheath 32 of the second electric wire portion 3, so that the adjacent region 62 extends continuously from the sheath 22 of the first electric wire portion 2 to the sheath 32 of the second electric wire portion 3. The end region 61, which is the region including the end of the waterproof portion 6 on the first electric wire portion 2 side, has a smoother surface than the entire adjacent region 62 occupying this wide region. Here, the adjacent region 62 is provided so as to reach the end of the waterproof portion 6 on the second electric wire portion 3 side. However, other than this embodiment, the end region may also be provided in the region including the end of the waterproof portion 6 on the second electric wire portion 3 side, occupying a part of the region where the waterproof portion 6 is surrounded by the sheet body 7 to cover the sheath 32, and may have a smoother surface than the adjacent region 62, similar to the end region 61 on the first electric wire portion 2 side. In the latter case, two end regions 61 having a smooth surface are separated by an adjacent region 62 having a less smooth surface.

[0035] The waterproof part 6 has a smoother surface in the end region 61 than in the adjacent region 62, and accordingly, the adhesion between the waterproof part 6 and the sheet body 7 is lower in the end region 61 than in the adjacent region 62. In this case, typically, the waterproof part 6 is strongly adhered to the sheet body 7 in the adjacent region 62, but in the end region 61, the waterproof part 6 is not adhered to the sheet body 7, or even if it is adhered, the adhesive strength is weaker than in the adjacent region 62.

[0036] The material constituting each part of the wire harness 1 is not particularly limited, but the following are examples of suitable materials. The conductor 41 constituting the electric wire 4 may be a single wire, but is preferably an aggregate of a plurality of element wires 41a. The metal material constituting the element wires 41a is not particularly limited, and examples thereof include copper, copper alloy, aluminum, and aluminum alloy. The conductor 41 may be made of only one type of element wire 41a, or may include two or more types of element wires 41a. The conductor 41 may include, in addition to the metal element wires 41a, element wires made of a material other than a metal material, such as organic fibers. The insulating coating 42 constituting the electric wire 4 is made of an insulating polymer material. Specific examples of the polymer material include polyolefins such as polypropylene (PP), halogen-based polymers such as polyvinyl chloride (PVC), thermoplastic elastomers, and rubber. These polymer materials may be used alone to constitute the insulating coating 42, or two or more types may be mixed together. Various additives may be added to the polymer material as appropriate. Examples of the additives include flame retardants, fillers, colorants, and the like.

[0037] The waterproof part 6 is composed of a curable resin material. That is, the resin material constituting the waterproof part 6 is composed of a cured product of a curable resin composition. The type of curability possessed by the resin material is not particularly limited, and any resin material having any curability that can be cured by various phenomena, such as photocurability, thermosetting, moisture curability, two-liquid reaction curability, dry curability (curability by evaporation and drying of a solvent), etc., can be used. The resin material may have two or more types of curability. However, from the viewpoint of the curing operation when forming the waterproof part 6 and the simplicity of the viscosity adjustment operation in the partial viscosity increase step described later, it is preferable that the resin material constituting the waterproof part 6 has photocurability, particularly ultraviolet curability.

[0038] The type of resin used for the resin material constituting the waterproof section 6 is not particularly limited, and examples thereof include silicone resins, acrylic resins, epoxy resins, urethane resins, and cyanoacrylate resins. Among these, it is preferable to use acrylic resins. Examples of photocurable acrylic resins include urethane (meth)acrylate resins, epoxy (meth)acrylate resins, and polyester (meth)acrylate resins. The resin material constituting the waterproof section 6 may be one type or a mixture of two or more types. In addition, various additives may be added to the resin material as appropriate. Examples of additives include reaction initiators, flame retardants, fillers, and colorants.

[0039] The material constituting the sheet body 7 is not particularly limited, and various resin materials can be used. Examples of the resin material include polyolefins such as polypropylene, halogen-based resins such as PVC, polyesters such as polyethylene terephthalate, and polyamides such as nylon. Various additives may be added to the resin material as appropriate. In addition, from the viewpoint of ease of arranging and fixing the sheet body 7 in a predetermined area on the outer periphery of the splice part 5 via the waterproof part 6, the sheet body 7 may be configured as an adhesive tape having an adhesive layer on which an adhesive or pressure-sensitive adhesive is arranged. In this case, the surface on which the adhesive layer is provided becomes the surface that contacts the waterproof part 6. In addition, when the resin material constituting the waterproof part 6 is a photocurable resin, the sheet body 7 is preferably made of a material that can transmit light used to harden the resin material so that the resin material can be hardened by light irradiation through the sheet body 7. The size of the sheet body 7 is not particularly limited as long as it is sufficient to cover the outer periphery of the waterproof portion 6, but it is preferable that the sheet body 7 has excess portions at both ends along the axial direction of the wire harness 1 that do not surround the waterproof portion 6 but only surround the electric wire portions 2, 3.

[0040] The sheet body 7 preferably contains a plasticizer. By containing a plasticizer, the flexibility of the sheet body 7 is improved, and the sheet body 7 can be arranged in the wire harness 1 by being flexibly folded or curved around the periphery of a predetermined region including the splice portion 5. Examples of the plasticizer include phthalate ester plasticizers such as diisononyl phthalate (DINP), trimellitic ester plasticizers such as tri-2-ethylhexyl trimellicate, aliphatic dibasic acid ester plasticizers such as 2-ethylhexyl adipate and dibutyl sebacicate, epoxy plasticizers such as epoxidized soybean oil, and phosphate ester plasticizers such as tricresyl phosphate. When the sheet body 7 has an adhesive layer, the adhesive layer may also contain a plasticizer. On the other hand, when the sheet body 7 contains a plasticizer, it is preferable that the resin material constituting the waterproof portion 6 does not contain a plasticizer or contains a plasticizer at a lower concentration than the sheet body 7. Among them, it is particularly preferable that the resin material constituting the waterproof portion 6 does not contain a plasticizer.

[0041] <Wire harness manufacturing method> Here, a method for manufacturing a wire harness according to an embodiment of the present disclosure will be described. One form of the wire harness manufactured by the manufacturing method according to this embodiment is the wire harness 1 having the end region 61 with a smooth surface at the end of the waterproof portion 6, as described above. The manufacturing method for the wire harness according to this embodiment uses a partial semi-curing method including a partial viscosity increasing step. Specifically, the wire harness is manufactured by carrying out (i) a joining step, (ii) a resin arranging step, (iii) a partial viscosity increasing step, (iv) a harness arranging step, (v) a surrounding step, and (vi) a curing step in this order. Each step will be described below in order. Each step is shown diagrammatically in Figs. 3A to 5.

[0042] (i)Joining process In the joining process, a plurality of electric wires 4 are bundled together to form an electric wire bundle, and then a splice portion 5 is formed to produce a harness precursor 1' as shown in FIG. 3A. Specifically, a required number of electric wires 4 cut to a predetermined length are first prepared, and the insulating coating 42 is removed from a portion of the axial direction of each of the electric wires 4 to expose the conductor 41. Then, a plurality of the electric wires 4 with a portion of the conductor 41 exposed are bundled together to form an electric wire bundle. The electric wire bundle has an exposed portion 21 where the conductor 41 of the electric wire 4 is exposed, and a covered portion 22 adjacent to the exposed portion 21 where the conductor 41 is covered with the insulating coating 42. Then, the plurality of electric wires 4 are joined to each other at the exposed portion 21 to form the splice portion 5. 3A, a harness precursor 1' is produced having a splice portion 5 in the form of an intermediate splice portion at a midpoint in the axial direction, and the harness precursor 1' has a bundle of electric wires as a first electric wire portion 2 on one side of the splice portion 5 along the axial direction, and has a second electric wire portion 3 including one electric wire 4 on the other side. In detail, an exposed conductor portion is formed at the middle portion of one main wire and at the terminal portions of two branch wires, and the three electric wires 4 are bundled together. The exposed conductor portions of the electric wires 4 are then joined to each other using joining means such as a crimp terminal to form the splice portion 5, thereby obtaining the harness precursor 1'.

[0043] (ii) Resin placement process Next, in the resin disposing step, a sheet body 7 and a resin composition R that will become the waterproof section 6 are prepared. Here, as shown in FIG. 3B, a curable liquid resin composition R is disposed on the surface of the sheet body 7 that has been spread out flat. The resin composition R hardens to become the resin material that constitutes the waterproof section 6. If the sheet body 7 has an adhesive layer, the resin composition R is disposed on the surface of the adhesive layer. In the example shown here, a resin composition R that has photocurability is used, and a sheet body 7 that is transparent to light that can harden the resin composition R is used.

[0044] In this resin disposing step, the resin composition R is disposed only in a partial region on the surface of the sheet body 7. In particular, regions where the resin composition R is not disposed are left on both sides along the axial direction (horizontal direction in the figure) of the harness precursor 1' to be disposed in the subsequent harness disposing step. In detail, the resin composition R is disposed in a region that will become the adjacent region 62 in the manufactured wire harness 1, and other regions are left in a state where the resin composition R is not disposed on the surface of the sheet body 7. At this time, from the viewpoint of disposing the resin composition R with high uniformity over the entire required region, it is preferable to dispense the liquid resin composition R in a planar manner on the surface of the sheet body 7, rather than dropping the liquid resin composition R in a spot shape on the surface of the sheet body 7 and letting it wet and spread due to the fluidity of the resin composition R. For example, it is preferable to use a wide nozzle N capable of discharging the resin composition R in a linear region, and discharge the resin composition R while moving the nozzle N. In the form shown in Figure 3B, the nozzle N, which is wider in the depth direction of the figure, is moved laterally as indicated by the arrow to eject the resin composition R, thereby distributing the resin composition R with high uniformity over a substantially rectangular area.

[0045] (iii) Partial viscosity increase step Next, a partial viscosity increasing process is performed on the resin composition R on the sheet body 7. In the partial viscosity increasing process, as shown in Fig. 3C, the viscosity of only a portion of the resin composition R arranged on the surface of the sheet body 7 is increased to form high-viscosity regions R1, R2. In the resin composition R, the portions other than the portions having the high-viscosity regions R1, R2 become liquid regions R3 in which the resin composition R remains in a liquid state having the low viscosity it had when it was initially supplied to the surface of the sheet body 7.

[0046] The high-viscosity regions are provided in two locations, a first region R1 including one end and a second region R2 including the other end, along the axial direction (horizontal direction in the drawing) of the harness precursor 1' to be placed in the subsequent harness placement step, in the region on the surface of the sheet body 7 where the resin composition R is placed. The first region R1 and the second region R2 are spaced apart from each other. The first region R1 and the second region R2 are each formed so as to occupy the entire region where the resin composition R is placed in a direction intersecting the axial direction of the harness precursor 1' (depth direction in the drawing). The region between the first region R1 and the second region R2 is left as a liquid region R3 where the viscosity of the resin composition R is not increased. The liquid region R3 is formed at a position including a region where the exposed portion 21 of the first electric wire portion 2 configured as an electric wire bundle is placed in the harness precursor 1' to be placed on the resin composition R in the subsequent harness placement step (see FIG. 4A). Specifically, the first portion R1 of the high viscosity region is provided in a region of the harness precursor 1' that corresponds to a part of the coating 22 of the first electric wire portion 2. More specifically, the first portion R1 is provided at a position slightly away from the boundary between the exposed portion 21 and the coating 22 of the first electric wire portion 2 toward the coating 22. The second portion R2 is provided continuously in a region that corresponds to a portion including the coating 32 to the splice portion 5 of the second electric wire portion 3. The liquid region R3 is provided in a portion including the exposed portion 21 side of the coating 22 of the first electric wire portion 2, and the exposed portion 21, that corresponds to between the first portion R1 and the second portion R2. The area occupied by the high viscosity region is preferably larger in the second portion R2 than in the first portion R1. For example, the width of the second portion R2 (the horizontal dimension in the figure) may be two or more times and five or less times the width of the first portion R1.

[0047] In the high viscosity regions R1 and R2, the resin composition R is in a semi-cured state, but is not completely cured. In other words, it is not in a solid state, but is a viscous or gel-like substance that maintains its viscosity. In the high viscosity regions R1 and R2, the resin composition R maintains such a viscous state throughout the thickness direction. In order to increase the viscosity of the curable resin composition R and to make it in a semi-cured state, an operation that can cure the resin composition R may be performed in a mild range that does not reach complete curing according to the curability of the resin composition R. When the resin composition R is photocurable, the viscosity of the resin composition R may be increased by irradiating the resin composition R with light. The accumulated light amount per unit area may be kept low within a range in which the resin composition R is not completely cured. Within such a range, the greater the accumulated light amount per unit area, the greater the viscosity of the resin composition R may be.

[0048] In order to selectively increase the viscosity of only a portion of the resin composition R arranged on the surface of the sheet body 7 and form the high-viscosity regions R1 and R2, the resin composition R in the region where the high-viscosity regions R1 and R2 are to be formed may be cured in a mild range that does not reach complete curing as described above. When the resin composition R has photocurability, a mask material M that blocks the irradiated light without transmitting it may be used. Specifically, only a portion of the resin composition R, that is, the region to be the liquid region R3, is covered with the mask material M, and light irradiation is performed using a light source device S such as a UV light source in a state where the region to be the liquid region R3 is not exposed to light. As shown in FIG. 3C, by performing light irradiation in a state where the region to be the liquid region R3 is covered with the mask material M, the viscosity of the resin composition R can be increased in the region other than the covered region, and the high-viscosity regions R1 and R2 can be formed. Light irradiation may be performed from the direction in which the resin composition R is disposed on the surface of the sheet body 7 (upward in the figure), or, as shown in the figure, from the direction in which the sheet body 7 is disposed (downward in the figure), and light may be irradiated onto the resin composition R through the sheet body 7. In the latter case, light irradiation is easily performed with the same arrangement of the light source device S as in the subsequent curing step. The viscosity of the resin composition R in the high-viscosity regions R1, R2 and the liquid region R3 is not particularly limited, but it is preferable that, for example, at room temperature and in the air, the viscosity is 50 Pa·s or more and 1000 Pa·s or less in the high-viscosity regions R1, R2 and less than 5 Pa·s in the liquid region R3.

[0049] (iv) Harness placement process Next, the harness precursor 1' is placed on the resin composition R that is placed on the surface of the sheet body 7 and has formed the high-viscosity regions R1, R2 and the liquid region R3. At this time, as shown in the plan view of FIG. 4A, the portion of the harness precursor 1', including the splice portion 5 and extending from the coating portion 21 of the first electric wire portion 2 to the coating portion 32 of the second electric wire portion 3, where the waterproof portion 6 is to be formed on the outer periphery, is placed on the surface of the resin composition R. In detail, when the harness precursor 1' is placed on the surface of the resin composition R, a part of the coating portion 22 of the first electric wire portion 2 that is slightly away from the boundary with the exposed portion 21 is brought into contact with the first portion R1 of the high-viscosity region. A part including the coating portion 32 of the second electric wire portion 3 to the splice portion 5 is brought into contact with the second portion R2. A part of the coating portion 22 of the first electric wire portion 2 that faces the boundary with the exposed portion 21 and a part including the entire exposed portion 21 are brought into contact with the liquid region R3. A partial area of ​​the splice portion 5 may be brought into contact with the liquid region R3.

[0050] (v) Enveloping Process Next, a surrounding step is performed, and the portion including the splice portion 5 of the harness precursor 1', which was placed on the surface of the resin composition R in the harness placement step, is covered with the surface of the sheet body 7 on which the resin composition R is placed. At this time, as shown in FIG. 4B, the sheet body 7 is first folded, curved and wrapped around, etc., so that the resin composition R placed on the surface of the sheet body 7 surrounds the entire periphery of the splice portion 5 and the coated portions 22, 32 and exposed portions 21, 31 of the two electric wire portions 2, 3, and the harness precursor 1' is wrapped with the sheet body 7 along the periphery. Furthermore, as shown in FIG. 4C, the sheet body 7 containing the resin composition R and the harness precursor 1' is squeezed to spread the resin composition R evenly over each portion of the region where the waterproof portion 6 of the harness precursor 1' is to be formed. In this case, the cross-sectional area of ​​the region surrounded by the sheet body 7 (the area of ​​the cross section perpendicular to the axial direction of the harness precursor 1') is narrowed, and as much void space as possible that is not occupied by the resin composition R is eliminated from the region between the surface of the sheet body 7 and the harness precursor 1'.

[0051] By carrying out this surrounding step, particularly the step of narrowing the sheet body 7 as shown in FIG. 4C, the resin composition R penetrates into small, complicated spaces such as gaps between constituent members in the harness precursor 1', and these spaces are filled with the resin composition R. The spaces between the electric wires 4 constituting the first electric wire portion 2 are also filled with the resin composition R in the exposed portion 21 and further in the coated portion 22. In particular, since the exposed portion 21 of the first electric wire portion 2 is in contact with the liquid region R3 in which the resin composition R maintains a high fluidity, the resin composition R constituting the liquid region R3 flows and densely fills the spaces between the electric wires 4 in the exposed portion 21 without gaps.

[0052] On the other hand, the regions arranged in contact with the first portion R1 and the second portion R2 of the high viscosity region, i.e., the region of the coating portion 22 of the first electric wire portion 2 away from the exposed portion 21, and the region extending from the splice portion 5 to the coating portion 32 of the second electric wire portion 3, are surrounded by the resin composition R with high viscosity. Although the viscosity of the resin composition R in the high viscosity regions R1 and R2 is increased, it is in a viscous state and has not completely lost its fluidity. Therefore, it adheres closely to the periphery of these regions and coats them.

[0053] In this surrounding step, particularly in the step of narrowing the sheet body 7, the cross-sectional area of ​​the region surrounded by the sheet body 7 is narrowed, so that the resin composition R having high fluidity that constitutes the liquid region R3 tends to flow and spread to both sides in the axial direction of the harness precursor 1', as shown by the arrows in the figure. However, in this embodiment, in the resin disposing step, the resin composition R is disposed only in a part of the region of the sheet body 7, and there is a region in which the resin composition R is not disposed at the outer edge of the sheet body 7, and in addition, high-viscosity regions R1 and R2 in which the viscosity of the resin composition R is increased and the fluidity is reduced are provided on both sides along the axial direction of the region in which the resin composition R is disposed. Therefore, even if the resin composition R in the liquid region R3 flows and spreads, it remains inside the region surrounded by the sheet body 7 and is unlikely to flow out to the outside of the sheet body 7. The resin composition R has high-viscosity regions R1 and R2 at both ends, which are low in fluidity. The resin composition R itself that constitutes the high-viscosity regions R1 and R2 does not flow easily. The high-viscosity regions R1 and R2 act as dikes, preventing the low-viscosity resin composition R in the liquid region R3 from freely flowing and spreading. The high-viscosity regions R1 and R2 act as dikes, so that the resin composition R in the liquid region R3 remains in the space between the high-viscosity regions R1 and R2 at both ends (retention form). Alternatively, a part of the resin composition R in the liquid region R3 spreads beyond the high-viscosity regions R1 and R2 (flow form). However, even when the resin composition R takes a flow form, the flow distance of the resin composition R and the amount of the resin composition R that flows are kept small compared to when the partial viscosity increase step is not performed and the high-viscosity regions R1 and R2 are not provided. Since the width of the high-viscosity region is small at the first portion R1 on the first electric wire portion 2 side and large at the second portion R2 on the second electric wire portion 3 side, when the resin composition assumes a flow form, the resin composition R is more likely to flow out of the liquid region R3 over the high-viscosity region at the first portion R1 and may or may not flow out of the second portion R2. In the illustrated form, in the flow form, the resin composition R of the liquid region R3 overflowing the first portion R1 of the high-viscosity region constitutes a flow portion R4 outside the high-viscosity region R1 along the axial direction.

[0054] In order to more effectively suppress the outflow of the resin composition R to the outside of the sheet body 7 in the surrounding step, the parameters involved in the formation of the waterproof part 6 may be adjusted so that the resin composition R is less likely to flow, or even if the resin composition R does flow, is less likely to outflow to the outside of the sheet body 7. For example, measures such as increasing the viscosity of the resin composition R in the high-viscosity regions R1, R2, increasing the area occupied by the high-viscosity regions R1, R2, increasing the area of ​​the sheet body 7, gently squeezing the sheet body 7, etc. may be used.

[0055] (vi) Curing process Finally, a curing step is performed to cure the resin composition R surrounded by the sheet body 7. At this time, the entire area of ​​the resin composition R, that is, the resin composition R that existed in the liquid region R3 including the flow portion R4, and the resin composition R that exists in the high viscosity regions R1 and R2 and is already in a semi-cured state, are cured to a solid state. At this time, a curing operation may be performed according to the curing property of the resin composition R. In the previous partial viscosity increase step, an operation for curing the resin composition R is performed, and a similar operation may be performed in this curing step, but it is necessary to set the curing conditions so that the degree of curing of the resin composition R is advanced in the entire area and a solid resin material can be obtained. When the resin composition R has photocurability, light irradiation by the light source device S may be performed on the entire area of ​​the resin composition R, that is, in a state where the mask material M is removed. Since the sheet body 7 has light transparency, the resin composition R surrounded by the sheet body 7 can be cured by irradiating light from the outside of the sheet body 7. In this case, the integrated amount of light per area is made larger than in the previous partial viscosity increase process, and the resin composition R in the high viscosity regions R1 and R2, which is already in a semi-cured state, is further cured to a solid state, and the liquid resin composition R originating from the liquid region R3 is also cured until it becomes a solid state.

[0056] Through this curing step, the wire harness 1 is obtained in which the region including the covering portion 22 and the exposed portion 21 of the first electric wire portion 2, the splice portion 5, and the exposed portion 31 and the covering portion 32 of the second electric wire portion 3 are covered with the waterproof portion 6, and the outer periphery of the waterproof portion 6 is protected by the sheet body 7. Since the outflow of the resin composition R to the outside of the sheet body 7 is suppressed in the surrounding step, the waterproof portion 6 is formed after the curing step as a portion that is entirely contained within the space surrounded by the sheet body 7. Alternatively, even if there are parts of the waterproof portion 6 that are not surrounded by the sheet body 7, the volume occupied by such parts is suppressed to be small. It is preferable to perform the curing step without leaving a time after the completion of the surrounding step so that the outflow of the resin composition R of the liquid region R3 that spread in the previous surrounding step does not progress. In the curing process, when the resin composition R is completely cured, the areas that were the high viscosity regions R1, R2, the liquid region R3, and the fluid region R4 before curing will have the same appearance except for the difference in surface smoothness, which will be explained in detail later, and the interfaces between them will be almost indistinguishable.

[0057] As described above, in the surrounding step, the resin composition R in the liquid region R3 may take a stagnant form in which it remains in the space between the high-viscosity regions R1 and R2 at both ends, or may take a flowing form in which a part of the resin composition R in the liquid region R3 spreads over the high-viscosity region R1. In the case of a stagnant form, the entire amount of the resin composition R remains in the region where the resin composition R was initially placed in the resin placement step. In the entire region, the resin composition R is cured in the partial viscosity increase step and the curing step while maintaining the initial state of being in close contact with the surface of the sheet body 7, and becomes the waterproof part 6. Therefore, the surface of the formed waterproof part 6 is cured in a state in which the fine uneven structure that the sheet body 7 has on its surface is transferred to the entire surface, and the smoothness is reduced.

[0058] On the other hand, when the resin composition R takes a flowing form rather than a stagnant form, the flowing portion R4 made of the resin composition R that has spread from the liquid region R3 over the high viscosity region R1 is cured in the curing process outside the region where the resin composition R was initially placed in the resin placement process. The resin composition R in the flowing portion R4 is cured in a state where it has not spread sufficiently on the surface of the sheet body 7, so that the curing proceeds without being in close contact with the sheet body 7. Therefore, the cured resin material is not easily affected by the uneven structure of the sheet body 7 on the surface, and the liquid resin composition R is cured while exposing the smooth surface characteristic of a liquid. The region where the smooth surface is exposed, which is generated by the curing of the flowing portion R4, becomes the end region 61. On the other hand, the areas adjacent to the end region 61 that were the initial high viscosity regions R1, R2 and liquid region R3 are cured while maintaining the initial state of being in close contact with the surface of the sheet body 7, as in the case of the above-mentioned stagnant form, and become adjacent regions 62 having a low smoothness surface to which the uneven structure of the sheet body 7 is transferred. In this way, by going through the flow form, a waterproof part 6 having adjacent end regions 61 with high surface smoothness and adjacent regions 62 with low surface smoothness is formed, and the wire harness 1 according to the embodiment described above is obtained. Both the wire harness 1 manufactured through the stagnant form and the wire harness manufactured through the flow form are suppressed from leaking the resin material to the outside of the sheet body 7 and have high waterproof properties.

[0059] <Relationship between waterproof structure and manufacturing method> As described above, in the manufacturing method of the wire harness according to the embodiment of the present disclosure, by applying the partial semi-curing method including the partial viscosity increasing step, both the suppression of leakage of the resin composition R to the outside of the sheet body 7 and the acquisition of high waterproofness are achieved. The high waterproofness is mainly obtained by the contribution of the resin composition R in the liquid region R3. By performing the surrounding step in a state in which the electric wire bundle of the first electric wire portion 2 is in contact with the liquid region R3 in which the resin composition R is maintained in a highly fluid state after the partial viscosity increasing step, the resin composition R that maintains its high fluidity penetrates into the spaces between the electric wires 4 (conductors 41) without gaps in the exposed portion 21 of the electric wire bundle. By performing the curing step in this state, as shown in the cross-sectional view of FIG. 6D, a waterproof portion 6 is obtained in which the spaces between the multiple electric wires 4 constituting the electric wire bundle of the first electric wire portion 2 are filled with the resin material without gaps, and the waterproof portion 6 has high waterproofness. On the other hand, since the resin composition R retains a certain degree of fluidity in the high-viscosity regions R1, R2, it adheres to the outer periphery of the two electric wire portions 2, 3 and the splice portion 5 and exhibits waterproofing after hardening. The regions covered with the high-viscosity regions R1, R2 do not have spaces inside that should be densely filled with resin material, such as the spaces between the multiple electric wires 4 in the exposed portion 21 of the first electric wire portion 2, and therefore, if the outer periphery is surrounded by the resin composition R with increased viscosity and covered with the resin material of the waterproof portion 6 with a degree of adhesion obtained after hardening, then waterproofing is sufficient.

[0060] The leakage of the resin composition R to the outside of the sheet body 7 is suppressed mainly by forming the high-viscosity regions R1 and R2. By increasing the viscosity of the resin composition R arranged on the surface of the sheet body 7 to form the high-viscosity regions R1 and R2, the resin composition R constituting the high-viscosity regions R1 and R2 is less likely to flow even after the surrounding process. In addition, by sandwiching the low-viscosity liquid region R3 between the high-viscosity regions R1 and R2, the high-viscosity regions R1 and R2 act as embankments, preventing the low-viscosity resin composition R in the liquid region R3 from flowing freely in the surrounding process. As described above, the resin composition R in the liquid region R3 may take either a stagnant form in which it remains between the high viscosity regions R1, R2, or a flowable form in which a part of it overcomes the high viscosity regions R1, R2 to form a flowable portion R4. When the resin composition R takes on a flowable form, the flowable portion R4 hardens to form an end region 61 at the end of the waterproof portion 6 on the first wire portion 2 side, as shown in Figure 6A, which has a smoother surface than the adjacent region 62.

[0061] Thus, the presence of the end region 61 in the waterproof part 6 is evidence that the waterproof part 6 is manufactured by a partial semi-curing method that undergoes a partial viscosity increase step. In other words, the waterproof part 6 has the end region 61 with a smoother surface than the adjacent region 62, which is an indicator that the waterproof part 6 is formed by reducing leakage of the resin composition R to the outside of the sheet body 7, and that the space between the electric wires 4 constituting the electric wire bundle is filled with the resin material without gaps, and has high waterproofing. Since the leakage of the resin composition R to the outside of the sheet body 7 is reduced, the liquid resin composition R is unlikely to flow out of the sheet body 7 during the manufacturing process of the waterproof part 6, especially in the surrounding process, and to reduce workability. In addition, in the waterproof part 6 obtained by curing the resin composition R, it is possible to reduce the effects of unnecessary contact with external objects, which may occur when the resin material leaks out of the sheet body 7 and hardens.

[0062] In the surrounding step, if the phenomenon that the resin composition R in the liquid region R3 overcomes the high-viscosity regions R1 and R2 to form a flow region R4 occurs only at the end of the first electric wire portion 2 side where the first portion R1 of the high-viscosity region is provided, and does not occur at the end of the second electric wire portion 3 side where the second portion R2 is provided, as shown in Figs. 1 and 2, the end region 61 with high surface smoothness is provided only at the end of the waterproof portion 6 on the first electric wire portion 2 side, and the entire other region, that is, the splice portion 5, which is a continuous region extending from the coating portion 22 of the first electric wire portion 2 to the coating portion 32 of the second electric wire portion 3, becomes the adjacent region 62 with relatively low surface smoothness. In this embodiment, since the second electric wire portion 3 includes only one electric wire 4, as shown in Fig. 4A, it is not necessary to provide the liquid region R3 in the region on the second electric wire portion 3 side from the splice portion 5 for the purpose of filling a narrow space or a complicated space with the resin composition R, and the entire region may be the high-viscosity region (second portion R2). In this case, the second region R2 can be formed to occupy a large area. Then, the area occupied by the high-viscosity regions R1 and R2 on the surface of the resin composition R becomes large, while the area occupied by the liquid region R3 becomes small, so that the flow of the resin composition R can be highly suppressed. However, if the flow of the resin composition R can be sufficiently suppressed, the second region R2 of the high-viscosity region may be formed to have a small area, and the resin composition R of the liquid region R3 may be allowed to pass over the second region R2 in addition to the first region R1 to form a flow portion on the second electric wire portion 3 side. In that case, in the waterproof portion 6, an end region 61 having a smoother surface than the adjacent region 62 is formed at the end of the second electric wire portion 3 side, similar to the end region 61 on the first electric wire portion 2 side. The adjacent region 62 is formed between the two end regions 61.

[0063] As described above, the end region 61, which has a smoother surface than the adjacent region 62, is formed at the end of the waterproof portion 6, which is evidence that the waterproof portion 6 was formed by the partial semi-curing method. In addition, the presence of the end region 61 itself contributes to improving the waterproofing of the waterproof portion 6. As described above, the end region 61 is formed when the flow portion R4 made of the resin composition R that has flowed from the liquid region R3 over the high viscosity region R1 hardens without strongly adhering to the sheet body 7. As a result, the end region 61 has a lower adhesiveness to the sheet body 7 than the adjacent region 62. Therefore, when the wire harness 1 is bent at the location where the waterproof portion 6 is formed or in the vicinity thereof, peeling stress is unlikely to occur between the waterproof portion 6 and the sheet body 7 in the end region 61. Peeling between the sheet body 7 and the waterproof portion 6 due to bending tends to progress from the end of the waterproof portion 6, but because peeling stress is unlikely to occur in the end region 61, peeling is unlikely to occur between the sheet body 7 and the waterproof portion 6 even when subjected to mechanical load such as bending. As a result, the waterproof property of the waterproof part 6 can be maintained at a high level even in a situation where mechanical load such as bending is applied. In addition, since the end of the waterproof part 6 has a smooth surface, water droplets are less likely to adhere to the end, and even if they do adhere, the water droplets are less likely to remain on the surface of the waterproof part 6. In this respect, too, the presence of the end region 61 enhances the waterproof effect of the waterproof part 6.

[0064] Furthermore, the smooth end region 61 also plays a role in suppressing the migration of substances between the sheet body 7 and the waterproof portion 6. The migration of substances between the sheet body 7 and the waterproof portion 6, including the migration of plasticizer from the sheet body 7 containing a plasticizer to the waterproof portion 6 that does not contain a plasticizer or contains a plasticizer at a lower concentration than the sheet body 7, occurs through the adhesion portion where the sheet body 7 and the waterproof portion 6 are strongly adhered to each other. However, if the adhesion strength between the sheet body 7 and the waterproof portion 6 in the end region 61 is low and the area of ​​the strong adhesion portion that serves as a migration path of substances is kept small, migration of substances such as plasticizers is less likely to occur. This suppresses the denaturation of the waterproof portion 6 and / or the sheet body 7 due to the migration of substances, and the associated decrease in waterproofness, and the wire harness 1 maintains a high waterproof state even after it has been used for a long period of time or in a high-temperature environment. For example, if migration of plasticizer occurs from the sheet body 7 to the waterproof portion 6, the adhesion of the resin material constituting the waterproof portion 6 to the sheet body 7 and the insulating coating 42 of the wire 4 will decrease, which may result in a decrease in waterproofness; however, the presence of the end region 61 suppresses the migration of the plasticizer, making such a decrease in waterproofness less likely to occur.

[0065] In fact, it has been confirmed by experiments that in the wire harness 1 in which the waterproof portion 6 is formed by the partial semi-curing method, the resin material does not leak from the sheet body 7, and an end region 61 having a higher surface smoothness than the adjacent region is formed at the end of the waterproof portion 6. FIG. 7 shows an enlarged photograph of the waterproof portion 6 actually formed by the partial semi-curing method, taken by peeling off the sheet body 7, near the end of the first electric wire portion 2, and at end position I, there is an area with a higher gloss than the position II to the right of it. This glossy area corresponds to the end region 61. The magnitude of the gloss indicates the degree of surface smoothness. It has been confirmed that the wire harness 1 in which the waterproof portion 6 is formed by the partial semi-curing method has high waterproofness both in the initial state immediately after the waterproof portion 6 is formed and in the state after the waterproof portion 6 is placed in a high-temperature environment.

[0066] With methods other than the partial semi-curing method, it is difficult to form a waterproof part 6 in which leakage of the resin material constituting the waterproof part 6 to the outside of the sheet body 7 is suppressed, the spaces between the electric wires 4 in the exposed parts 21 of the first electric wire parts 2 are filled with the resin material without any gaps, and further the end parts have end regions 61 with smooth surfaces. For example, it has been experimentally confirmed that when the waterproof part 6 is formed by the one-step curing method or the full area semi-curing method described below, a waterproof part 6 that satisfies all of these configurations cannot be obtained.

[0067] First, a case where the waterproof part 6 is formed by the one-step curing method will be described. In the one-step curing method, the partial viscosity increasing step in the partial semi-curing method is not performed, and the entire area of ​​the resin composition R placed on the sheet surface in the resin placing step is kept in a liquid state, and the harness placing step, the surrounding step, and the curing step are performed. In this case, the resin composition R in a highly fluid state can penetrate into small spaces and complicated spaces between the components of the wire harness in the area where the waterproof part 6 is to be formed, so that, as shown in FIG. 6E, the resin material is filled without gaps in the spaces between the electric wires 4 constituting the electric wire bundle. On the other hand, since the resin composition R has high fluidity, in the surrounding step, the resin composition R tends to flow out to the outside of the sheet body 7, and in the curing step, it tends to be cured outside the sheet body 7 as it is. In addition, as shown in FIG. 6B, the waterproof part 6 is cured in a state of being in close contact with the sheet body 7 in the entire area surrounded by the sheet body 7, including the end portion, so that the surface of the waterproof part 6 has a low smoothness to which the fine unevenness of the sheet body 7 is transferred. As a result, the effect of improving waterproofness due to the presence of the smooth edge region 61 cannot be obtained. In particular, when exposed to a high temperature environment, the waterproofness of the waterproof portion 6 decreases due to migration of the plasticizer from the sheet body 7 to the waterproof portion 6. Even in experiments, in the initial state immediately after the waterproof portion 6 was formed, the waterproof portion 6 exhibited high waterproofness equivalent to that when the partial semi-curing method was used, but when exposed to a high temperature environment, the waterproofness decreased significantly.

[0068] Next, a case where the waterproof part 6 is formed by the full semi-curing method will be described. In the full semi-curing method, unlike the partial semi-curing method in which the partial viscosity increasing step is performed to increase the viscosity of the resin composition R only in a part of the region, the full semi-curing method increases the viscosity of the resin composition R arranged on the surface of the sheet body 7 in the resin arrangement step, and makes it a viscous or gel-like substance. When the resin composition R has photocurability, the viscosity of the entire resin composition R can be increased by irradiating the resin composition R with light without using the mask material M and limiting the accumulated light amount to a level that allows the resin composition R to be semi-cured without being completely cured. Thereafter, the harness arrangement step, the surrounding step, and the curing step are performed. In this case, the surrounding step is performed in a state in which the entire resin composition R has a high viscosity, so that the resin material does not leak out of the sheet body 7. In addition, the resin composition R, which has become highly viscous, shows some flow in the region surrounded by the sheet body 7 in the surrounding process, and the flowed portion is cured in the curing process without adhering to the sheet body 7. As a result, as shown in FIG. 6C, a region with a smoother surface than the adjacent region is formed at the end of the waterproof portion 6. However, since the waterproof portion 6 is formed by contacting the exposed portion 21 of the wire bundle of the harness precursor 1' with the resin composition R, which has become highly viscous and has low fluidity, the resin composition R cannot sufficiently penetrate into the region between the wires 4 constituting the wire bundle. As a result, as shown in the cross-sectional view in FIG. 6F, a void V that is not filled with the resin material is formed between the wires 4 constituting the wire bundle. This void V reduces the waterproofness of the waterproof portion 6. In the experiment, only low waterproofness was obtained from the initial state immediately after the waterproof portion 6 was formed, and the waterproofness was clearly inferior to that when the partial semi-curing method was used. Similarly, when using a resin composition R whose viscosity has been increased by a method other than semi-curing by light irradiation, such as by adding a thickener or gelling agent, the waterproof portion 6 will have areas with improved surface smoothness at its ends, but will also tend to have voids V between the wires 4 that make up the wire bundle that are not filled with the resin material.

[0069] <Other forms> In the wire harness 1 described above, the splice portion 5 is configured as an intermediate splice portion, and the first wire portion 2 consisting of an electric wire bundle including a plurality of electric wires 4 and the second wire portion 3 including only one electric wire 4 are provided on both sides of the splice portion 5. However, the wire harness of the present disclosure is not limited to this form, and may be any wire harness having an electric wire bundle including a plurality of electric wires, a splice portion, a waterproof portion, and a sheet body, in which the splice portion joins the electric wires constituting the electric wire bundle to each other at their exposed portions, the waterproof portion covers the splice portion, the exposed portion of the electric wire bundle, and the covered portion with a curable resin material, and further the sheet body surrounds the outer periphery of the waterproof portion. In the exposed portion, the waterproof portion fills the spaces between the multiple electric wires that make up the electric wire bundle with a resin material without leaving any gaps, and further, along the axial direction of the electric wire bundle, among the region that is surrounded by the sheet body to cover the covering portion, a portion of the region including the end is defined as an end region, and a region adjacent to the end region is defined as an adjacent region, and the end region may have a smoother surface than the adjacent region.

[0070] For example, when the splice portion 5 is formed in the form of an intermediate splice portion, the second electric wire portion 3 may also be configured as an electric wire bundle including a plurality of electric wires 4, similar to the first electric wire portion 2. In that case, it is preferable that the waterproof portion 6 is configured to fill the spaces between the electric wires 4 constituting the electric wire bundle with a resin material without any gaps not only in the exposed portion 21 of the first electric wire portion 2 but also in the exposed portion 31 of the second electric wire portion 3. It is also preferable that the waterproof portion 6 has end regions 61 not only in a region including the end on the first electric wire portion 2 side but also in a region including the end on the second electric wire portion 3 side, and that both of the end regions 61 on both ends have a smooth surface compared to the adjacent region 62 occupying between them. In order to form the waterproof portion 6 having the end region 61 also on the second electric wire portion 3 side in this way, in the partial viscosity increasing step, the second portion R2 of the high viscosity region may be provided, like the first portion R1, in a region corresponding to a part of the coated portion 32 of the second electric wire portion 3 of the harness precursor 1', more specifically, at a position slightly away from the boundary between the exposed portion 31 and the coated portion 32 of the second electric wire portion 3 on the coated portion 32 side. The entire region sandwiched between the first portion R1 and the second portion R2 of the high viscosity region may be made into a liquid region R3.

[0071] Furthermore, the splice portion does not necessarily have to be formed as an intermediate splice portion having the first electric wire portion 2 and the second electric wire portion 3 at both ends. For example, a splice portion may be formed at an end of an electric wire bundle in which a plurality of electric wires 4 are bundled, and the waterproof portion 6 and the sheet body 7 may be disposed around the outer periphery of the splice portion.

[0072] In addition, the above-described wire harness 1 mainly deals with a form in which the entire waterproof portion 6 is contained inside the area surrounded by the sheet body 7. However, the present invention is not necessarily limited to such a form, and a part of the waterproof portion 6 may be formed outside the area surrounded by the sheet body 7. For example, the resin composition constituting the waterproof portion 6 may leak out of a part of the end of the waterproof portion 6 as a whole along the outer periphery of the covering portion 22 of the first electric wire portion 2 configured as an electric wire bundle. Even in such a case, the end of the area of ​​the waterproof portion 6 that is surrounded by the sheet body 7 and covers the covering portion 22 of the first electric wire portion 2, that is, the end of the area excluding the part that is outside the sheet body 7, is set as the end area 61, and the end area 61 may have a smoother surface than the adjacent area 62 (the area that is surrounded by the sheet body 7 and covers the covering portion 22 of the first electric wire portion 2, the area adjacent to the end area 62). In this way, the structure in which a part of the waterproof portion 6 is outside the sheet body 7 can also be formed by the partial semi-curing method described above. Such a structure is formed when a part of the flowable portion R4 flows out to the outside of the sheet body 7 in the enclosing step. In this way, even if a part of the resin composition constituting the waterproof portion 6 leaks out of the area enclosed by the sheet body 7, the partial semi-curing method reduces the leakage of the resin composition constituting the waterproof portion 6 from the sheet body 7 compared to the case of using the one-stage curing method, and high waterproofing is ensured. However, in the formed waterproof portion 6, it is preferable that there are at least some areas along the outer periphery of the coating portion 22 of the first electric wire portion 2 where the resin composition constituting the waterproof portion 6 does not leak out of the sheet body 7.

[0073] Although the embodiments of the present disclosure have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present invention. [Explanation of symbols]

[0074] 1 Wire harness 1' Harness precursor 2 First electric wire section 21 Exposed portion of first electric wire 22 Covering part of first electric wire part 3 Second electric wire section 31 Exposed portion of second electric wire 32 Covering part of second electric wire part 4 electric wire 41 Conductor 41a Bare wire 42 Insulation coating 5 Splice 6 Waterproof part 61 End area 62 Adjacent Area 7 Sheet body M Masking material N Nozzle R Uncured resin composition R1: First part of high viscosity region R2: The second part of the high viscosity region R3 Liquid region R4 Flow section S Light source device V void

Claims

1. The cable includes a wire bundle, a splice portion, a waterproof portion, and a sheet body, The wire bundle includes a plurality of wires, The electric wire has a conductor and an insulating coating that covers an outer periphery of the conductor, The wire bundle includes an exposed portion in which the conductor is exposed from the insulating coating of the electric wire, and a covered portion adjacent to the exposed portion in which the conductor is covered with the insulating coating, the splice portion joins the electric wires constituting the electric wire bundle to each other at the exposed portion, the waterproof portion is configured to cover the splice portion, the exposed portion, and the covered portion with a curable resin material; The sheet body surrounds the outer periphery of the waterproof part, The waterproof portion is In the exposed portion, spaces between the plurality of electric wires constituting the electric wire bundle are filled with the resin material without any gaps, a region that is surrounded by the sheet body and covers the covering portion along an axial direction of the wire bundle, the region including the end being defined as an end region, and a region adjacent to the end region being defined as an adjacent region, the end region having a smoother surface than the adjacent region.

2. The wire harness according to claim 1 , wherein the waterproof portion is entirely contained within an area surrounded by the sheet body.

3. the sheet body is made of a resin material containing a plasticizer, 3. The wire harness according to claim 1, wherein the resin material constituting the waterproof portion does not contain a plasticizer or contains a plasticizer at a lower concentration than the sheet body.

4. 3. The wire harness according to claim 1, wherein in the waterproof portion, the adjacent region extends continuously at least to a region covering the splice portion, and the end region has a smoother surface than the entire adjacent region.

5. The wire harness has the splice portion as an intermediate splice portion at a midpoint in an axial direction, and has the electric wire bundle as a first electric wire portion on one side of the splice portion along the axial direction, and has a second electric wire portion including one or more of the electric wires on the other side, The waterproof portion is a region extending from the covering portion of the first electric wire portion to the covering portion of the second electric wire portion is covered, The wire harness according to claim 4 , wherein the end region is provided in at least a partial region including an end portion on the first electric wire portion side.

6. a joining process in which a plurality of electric wires each having a conductor and an insulating coating covering an outer periphery of the conductor are bundled together after removing the insulating coating from a portion thereof to form an electric wire bundle having an exposed portion where the conductor is exposed and a covered portion adjacent to the exposed portion where the conductor is covered with the insulating coating, and the electric wires are joined to each other at the exposed portion to form a splice portion, thereby producing a harness precursor; a resin disposing step of disposing a curable liquid resin composition on a partial region of a surface of a sheet body; a partial viscosity increasing step of increasing the viscosity of only a portion of the resin composition placed on the surface of the sheet body to form a high-viscosity region, and leaving the other region as a liquid region; a harness placement step of placing a portion of the harness precursor including the splice portion on a surface of the resin composition such that the exposed portion of the electric wire bundle is in contact with the liquid region; a surrounding step of surrounding the harness precursor with the surface of the sheet body on which the resin composition is disposed; a curing step of curing the resin composition surrounded by the sheet body over the entire area; In the partial viscosity increasing step, the high-viscosity region is provided in a first portion and a second portion that are spaced apart from each other and include one end and the other end, respectively, along an axial direction of the harness precursor, in the region in which the resin composition is disposed; and providing the liquid region between the first portion and the second portion, including a region where the exposed portion of the electric wire bundle is disposed.

7. The resin composition has photocurability, the sheet body is transparent to light capable of curing the resin composition, In the partial viscosity increasing step, a region of the resin composition disposed on the surface of the sheet body that is to be the liquid region is covered with a mask material that blocks light, and the resin composition is irradiated with light to bring the resin composition into a semi-cured state in the high-viscosity region. The method for producing a wire harness according to claim 6, wherein in the curing step, the resin composition is cured by irradiating an entire area of ​​the resin composition with light from an outside of the sheet body surrounding the harness precursor.

8. the sheet body is made of a resin material containing a plasticizer, The method for producing a wire harness according to claim 6 or 7, wherein the resin composition does not contain a plasticizer or contains a plasticizer at a lower concentration than the sheet body.

9. the harness precursor has the splice portion as an intermediate splice portion at a midpoint in the axial direction, the wire bundle as a first wire portion on one side of the splice portion along the axial direction, and a second wire portion including one or more of the wires on the other side, In the resin disposing step, the resin composition is continuously disposed at a position corresponding to a region including a portion from the coated portion of the first electric wire portion to the coated portion of the second electric wire portion of the harness precursor, In the partial viscosity increasing step, the high viscosity region is the first portion is provided in a region corresponding to a part of the coating portion of the first electric wire portion, The method for manufacturing a wire harness according to claim 6 or 7, wherein the second portion is provided to include a region corresponding to a part of the covering portion of the second electric wire portion.

10. The second electric wire portion includes only one electric wire, The method for manufacturing a wire harness according to claim 9, wherein in the partial viscosity increasing step, the second portion is provided continuously in a region corresponding to a portion extending from the splice portion to the covering portion of the second electric wire portion.

Images