Conductor connection structure and method for manufacturing the same

Abstract

To provide a conductor connection structure with little melt-off at a butting joint portion.SOLUTION: A conductor connection structure 1 includes an element wire bundle 11 in which a plurality of element wires 13 are bundled together, an electric wire 10 in which an end portion of the wire bundle 11 is formed in a plate shape, a conductor 20 whose end portion is formed in a plate shape, and a backing metal 30 formed of a metal plate-shaped member. The end portion of the element wire bundle 11 is joined to the end portion of the conductor 20 in a butted state, and the backing metal 30 surrounds a joint portion W between the element wire bundle 11 and the conductor 20 in a state where the backing metal 30 is in contact with and along the joint portion W, and the backing metal 30 is joined via the joint W.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a conductor connection structure and a method for manufacturing the conductor connection structure.

Background Art

[0002] Automobiles are equipped with a variety of electronic devices, and wire harnesses are routed to electrically connect the electronic devices. A wire harness includes a plurality of electric wires and connectors, and terminals are connected to the ends of the respective electric wires. Then, the wire harness is formed by connecting the terminals to the connectors.

[0003] Patent Document 1 discloses a wire with a terminal including an electric wire and a terminal connected to a conductor portion exposed at one end of the electric wire. The conductor portion includes a plurality of strands, has a fusion joint portion where the ends of the plurality of strands are fusion-bonded on one end side of the electric wire, and discloses that the fusion joint portion is connected to the terminal.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, in the conductor connection structure of Patent Document 1, when the supply of heat to the butted portion is insufficient, there is a risk of insufficient bonding. On the other hand, if heat is excessively supplied to the butted portion to avoid insufficient bonding, there is a risk that the side and bottom surfaces of the butted portion will melt away. Thus, in the conventional conductor connection structure, it has not been easy to set the bonding conditions of the butted portion.

[0006] The present invention has been made in view of the problems of such prior art. And an object of the present invention is to provide a conductor connection structure with less melting loss at the butted joint portion and a method for manufacturing the conductor connection structure.

Means for Solving the Problems

[0007] The conductor connection structure according to an aspect of the present invention includes a stranded wire bundle in which a plurality of strands are bundled, an electric wire having an end portion of the stranded wire bundle formed in a plate shape, a conductor having an end portion formed in a plate shape, and a backing metal formed of a metal plate member. The end portion of the stranded wire bundle is joined in a butted state with respect to the end portion of the conductor. The backing metal surrounds the joint portion in a state of being in contact with and along the joint portion between the stranded wire bundle and the conductor. The backing metal is joined via the joint portion.

[0008] The method for manufacturing a conductor connection structure according to another aspect of the present invention includes a step of preparing an electric wire having an end portion of a stranded wire bundle in which a plurality of strands are bundled and formed in a plate shape, a conductor having an end portion formed in a plate shape, and a backing metal formed of a metal plate member. The method for manufacturing a conductor connection structure includes a step of butting the end portion of the stranded wire bundle and the end portion of the conductor, joining them in a state of being surrounded by the backing metal, and joining the backing metal via the joint portion.

Effects of the Invention

[0009] According to the present invention, it is possible to provide a conductor connection structure with less melting loss at the butted joint portion and a method for manufacturing the conductor connection structure.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the conductor connection structure and the manufacturing method of the conductor connection structure according to the present embodiment will be described in detail with reference to the drawings. Note that the dimensional ratios in the drawings are exaggerated for the convenience of explanation and may be different from the actual ratios.

[0012] [First Embodiment] [Conductor Connection Structure] First, the conductor connection structure 1 according to the first embodiment will be described. FIG. 1 is a front view showing an example of the conductor connection structure 1. FIG. 2 is a plan view showing an example of the conductor connection structure 1. FIG. 3 is a cross-sectional view taken along line III-III of FIG. 2. As shown in FIGS. 1 to 3, the conductor connection structure 1 according to the present embodiment includes an electric wire 10, a conductor 20, and a back-up metal 30.

[0013] The conductor connection structure 1 according to the present embodiment may be a wire with a conductor and can be used as a wire harness routed in an automobile or the like. In this specification, the direction in which the electric wire 10 and the conductor 20 abut against each other is defined as the length direction X, the direction perpendicular to the length direction X is defined as the width direction Y, and the direction perpendicular to the length direction X and the width direction Y is defined as the height direction Z for explanation.

[0014] The electric wire 10 includes a strand bundle 11 and an insulating coating 12 that covers the outer periphery of the strand bundle 11. At the end of the electric wire 10, the insulating coating 12 is stripped off, and the strand bundle 11 is exposed from the insulating coating 12. The strand bundle 11 includes a plurality of strands 13, and the plurality of strands 13 are bundled together. At the end of the strand bundle 11, the plurality of strands 13 are joined to each other, and as shown in FIG. 4, the end of the strand bundle 11 is formed in a plate shape. The end of the strand bundle 11 may be formed in the same plate shape as the end of the conductor 20. The plurality of strands 13 may include a collective stranded wire formed by bundling a plurality of strands. Also, the strand bundle 11 may be composed of only one collective stranded wire, or may be a composite stranded wire formed by bundling a plurality of collective stranded wires.

[0015] Each of the plurality of strands 13 may contain copper or aluminum as a main component. Here, the main component means the metal with the highest molar ratio among the metals contained in each strand 13. Among the metals contained in each strand 13, the metal with the highest molar ratio may be contained at 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more in terms of molar ratio. The material of each strand 13 may be, for example, copper, aluminum, or an alloy containing these metals. From the perspective of weight reduction, it is preferable that each of the plurality of strands 13 is formed of aluminum or an aluminum alloy.

[0016] As the material of the insulating coating 12, a thermoplastic resin capable of ensuring electrical insulation can be used. The material of the insulating coating 12 may contain, for example, at least one of an olefin-based resin and polyvinyl chloride. The olefin-based resin may contain, for example, at least one or more resins selected from the group consisting of polyethylene (PE), polypropylene (PP), ethylene copolymers, and propylene copolymers.

[0017] The end of the conductor 20 is formed in a plate shape. Also, the conductor 20 is formed of a conductive metal. The conductor 20 may be formed of a single metal plate, or as shown in FIG. 5, it may be a stack of a plurality of plates 22. When stacking a plurality of plates 22, the conductor 20 can be made to have a desired thickness by increasing or decreasing the number of plates 22. The conductor 20 may be, for example, a bus bar.

[0018] The end of the strand bundle 11 is joined in a butted state with respect to the end of the conductor 20. And the strand bundle 11 and the conductor 20 are connected via a joint portion W. By butting and joining the end of the strand bundle 11 and the end of the conductor 20, it is possible to connect in a space-saving manner compared to connecting by overlapping, and the added value can be improved.

[0019] The conductor 20 may contain copper or aluminum as a main component. Here, the main component means the metal with the highest molar ratio among the metals contained in the conductor 20. Among the metals contained in the conductor 20, the metal with the highest molar ratio may be contained in a molar ratio of 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more. The material of the conductor 20 may be, for example, an alloy containing these metals such as copper or aluminum. From the viewpoint of conductivity, the conductor 20 is preferably formed of copper or a copper alloy.

[0020] The backing plate 30 is formed of a plate-shaped metal member. The backing plate 30 includes a bottom wall 31 and a pair of side walls 32. The bottom wall 31 extends in the length direction X and the width direction Y. The pair of side walls 32 extend in the height direction Z from both ends in the width direction Y of the bottom wall 31, respectively. In the present embodiment, the backing plate 30 is a single plate-shaped member and is formed by bending the plate-shaped member. The thickness of the plate-shaped member may be 0.1 mm or more and 0.5 mm or less. That is, the thicknesses of the bottom wall 31 and the side walls 32 may each be 0.1 mm or more and 0.5 mm or less.

[0021] The back-up metal 30 is in contact with and surrounds the joint W between the stranded wire bundle 11 and the conductor 20 along the joint W. By surrounding the joint W with the back-up metal 30, in the case of welding and joining the stranded wire bundle 11 and the conductor 20, etc., since the back-up metal 30 serves as a receiving tray, it is possible to suppress the molten material from melting and falling below the stranded wire bundle 11 or the conductor 20. Further, when the back-up metal 30 includes the bottom wall 31 and the side wall 32, it is also possible to suppress the material on the side surface from melting and falling during joining. Since it is possible to suppress the material from melting and falling, the stranded wire bundle 11 or the conductor 20 can be melted under slightly stronger conditions, so that joining defects can be suppressed. Further, since the joining conditions can be strengthened, the control range of the joining conditions can be widened, and the productivity can be improved. Furthermore, even when covering the stranded wire bundle 11, the conductor 20, and the back-up metal 30 with a covering material such as an insulating tape or a tube for insulation, it is possible to suppress the material from falling out and causing protrusions. Therefore, the covering material is not easily torn by the protrusions, and the thickness of the covering material can be reduced.

[0022] The back-up metal 30 is joined via the joint W. By joining the back-up metal 30 to the joint W, the joining strength between the stranded wire bundle 11 and the conductor 20 can be further improved. In the present embodiment, the end of the stranded wire bundle 11 is formed in a rectangular shape, and the end of the conductor 20 is also formed in a rectangular shape. The ends of the stranded wire bundle 11 and the conductor 20 have the same shape, and since the stranded wire bundle 11 and the conductor 20 are joined via the joint W, the peripheral surfaces including the bottom surface and the side surfaces of the end of the stranded wire bundle 11 and the conductor 20 are formed on the same plane.

[0023] The backing metal 30 surrounds the joint W in a state of straddling the wire bundle 11 and the conductor 20. The bottom wall 31 is in contact with the bottom surfaces of the wire bundle 11, the conductor 20, and the joint W. Each side wall 32 is in contact with the side surfaces of the wire bundle 11, the conductor 20, and the joint W. The joint W may be a portion where the wire bundle 11 and the conductor 20 are joined, or at least one of the bottom wall 31 and the side wall 32 of the backing metal 30 may also be joined. In the backing metal 30, the wire bundle 11 and the conductor 20 are placed on the bottom wall 31. And, in the backing metal 30, a joint W where the wire bundle 11 and the conductor 20 are joined is arranged.

[0024] The backing metal 30 may contain copper or aluminum as a main component. Here, the main component means the metal having the largest molar ratio among the metals contained in the backing metal 30. Among the metals contained in the backing metal 30, the metal having the largest molar ratio may be contained at 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more in terms of molar ratio. The material of the backing metal 30 may be, for example, copper, aluminum, or an alloy containing these metals, respectively. From the viewpoint of conductivity, it is preferable that the backing metal 30 is formed of copper or a copper alloy.

[0025] [Manufacturing Method of Conductor Connection Structure] Next, a manufacturing method of the conductor connection structure 1 according to the present embodiment will be described. Note that the same components as those in the above embodiment are denoted by the same reference numerals, and descriptions of portions overlapping with the above embodiment are omitted. The manufacturing method of the conductor connection structure 1 according to the present embodiment includes a preparation step and a joining step. By such steps, the conductor connection structure 1 can be manufactured.

[0026] (Preparation Step) The preparation step is a step of preparing the electric wire 10, the conductor 20, and the backing metal 30.

[0027] As shown in FIGS. 4 and 9, the electric wire 10 includes a stranded wire bundle 11 and an insulating coating 12 that covers the outer periphery of the stranded wire bundle 11, and the stranded wire bundle 11 is exposed from the insulating coating 12. The stranded wire bundle 11 includes a plurality of individual wires 13, and the plurality of individual wires 13 are bundled together. At the end of the stranded wire bundle 11, the plurality of individual wires 13 are joined together, and thus the end of the stranded wire bundle 11 is formed in a plate shape. The joining method is not particularly limited, and examples include ultrasonic joining and heat joining.

[0028] As shown in FIG. 4, the stranded wire bundle 11 has an end face 14. The end face 14 of the stranded wire bundle 11 is formed to have the same shape as the end face 21 of the conductor 20. In the present embodiment, the end face 14 of the stranded wire bundle 11 is formed in a plate shape with a rectangular cross-section. The aspect ratio of the end face 14 of the stranded wire bundle 11 may be 1 to 8. When the aspect ratio of the stranded wire bundle 11 is within the above range, good connectivity, conduction performance, and connection strength can be ensured. Note that the aspect ratio is the ratio of the width b to the height a of the end face 14 of the stranded wire bundle 11. The height a of the end face 14 of the stranded wire bundle 11 is the length of the end face 14 that is the longest in the height direction Z. The width b of the end face 14 is the length of the end face 14 that is the longest in the width direction Y.

[0029] As shown in FIG. 5, the end of the conductor 20 is formed in a plate shape. The conductor 20 has an end face 21 that extends in the width direction Y and the height direction Z at the end in the length direction X. In the present embodiment, the end face 21 of the conductor 20 is formed in a rectangular shape. The aspect ratio of the end face 21 of the conductor 20 may be 1 to 8. When the aspect ratio of the end face 21 is within the above range, good connectivity, conduction performance, and connection strength can be ensured. Note that the aspect ratio is the ratio of the width b to the height a of the end face 21 of the conductor 20. The height a of the end face 21 of the conductor 20 is the length of the end face 21 that is the longest in the height direction Z. The width b of the end face 21 is the length of the end face 21 that is the longest in the width direction Y. The height a of the conductor 20 may be 3 mm or more and 6 mm or less. The width b of the conductor 20 may be 3 mm or more and 48 mm or less.

[0030] As shown in FIGS. 6 to 8, the backing metal 30 is formed of a metal plate-like member. The backing metal 30 includes a bottom wall 31 and a pair of side walls 32.

[0031] (Bonding process) As shown in FIG. 9, the bonding process is a process of butting the end of the strand bundle 11 and the end of the conductor 20 and bonding them in a state where the end of the strand bundle 11 and the end of the conductor 20 are surrounded by the backing metal 30. By such a process, the end of the strand bundle 11 is bonded to the end of the conductor 20 in a butted state. Also, the bonding process is a process of bonding the backing metal 30 via the bonding portion W. By such a process, the end of the strand bundle 11 is bonded to the end of the conductor 20 in a butted state. Further, the backing metal 30 surrounds the bonding portion W in a state of being in contact with and along the bonding portion W between the strand bundle 11 and the conductor 20. And the backing metal 30 is bonded via the bonding portion W.

[0032] In the bonding process, the end of the strand bundle 11 and the end of the conductor 20 may be melted and bonded, for example, by laser welding. As shown in FIG. 9, in the bonding process, the end of the strand bundle 11 and the end of the conductor 20 may be bonded by a laser. In a bonding method such as laser welding, high energy can be concentrated in a narrow range and the control is also easy. Also, in laser welding, since the laser can penetrate deeply into the metal, the metal can be melted deeply.

[0033] Here, if the melting of the end of the strand bundle 11 and the end of the conductor 20 is insufficient, a portion where the strand bundle 11 and the conductor 20 are not bonded will occur, and the bonding strength between the strand bundle 11 and the conductor 20 will be weakened. On the other hand, if the end of the strand bundle 11 and the end of the conductor 20 are melted too much, the metal at these ends will melt away and the bonding area will become small, so the bonding strength between the strand bundle 11 and the conductor 20 will be weakened.

[0034] Therefore, in the joining step according to the present embodiment, the end portion of the stranded wire bundle 11 and the end portion of the conductor 20 are joined in a state of being surrounded by the backing metal 30. Thereby, even when the end portion of the stranded wire bundle 11 and the end portion of the conductor 20 are melted too much, the backing metal 30 serves as a receiving tray to receive the melted metal, so that it is possible to suppress the melting and dropping of the metal. Further, even when the metal is melted excessively, the end portion of the stranded wire bundle 11 and the end portion of the conductor 20 can be joined within the backing metal 30. Therefore, by melting the metal under slightly stronger conditions, it is possible to suppress joining defects due to insufficient melting.

[0035] In the above embodiment, both the end face 14 of the stranded wire bundle 11 and the end face 21 of the conductor 20 are rectangular, but the present disclosure is not limited to such a form. The end face 14 of the stranded wire bundle 11 and the end face 21 of the conductor 20 may be elliptical with a width longer than the height.

[0036] [Second Embodiment] Next, the conductor connection structure 1 according to the second embodiment will be described with reference to FIGS. 10 to 12. The conductor connection structure 1 according to the second embodiment is provided with an engagement protrusion 41 for engaging an inspection jig with the backing metal 30 as compared with the conductor connection structure 1 according to the first embodiment. Since the other points are the same as those of the conductor connection structure 1 and the manufacturing method of the conductor connection structure 1 according to the first embodiment, the description thereof will be omitted.

[0037] As shown in FIGS. 10 to 12, the backing metal 30 according to the present embodiment is provided with an engagement protrusion 41 for engaging an inspection jig. The engagement protrusion 41 protrudes from the inner surface to the outer surface of the backing metal 30 where the stranded wire bundle 11 or the conductor 20 is disposed. The engagement protrusion 41 can be formed by protruding a single plate by pressing or the like. The height of the engagement protrusion 41 is preferably 1 mm or more and 1.5 mm or more. By setting the height of the engagement protrusion 41 within such a range, it is possible to easily engage an inspection jig including a rod-shaped engagement portion such as a wire with the engagement protrusion 41.

[0038] By engaging an inspection jig (not shown) with the engaging projection 41 and pulling it, the quality of the joint can be determined. For example, when the backing metal 30 is not sufficiently joined to the joint portion W, if the inspection jig is engaged with the engaging projection 41 and pulled, the backing metal 30 will float or deform. Therefore, by checking the joint state of the backing metal 30 with the inspection jig, the conductor connection structure 1 with insufficient joint can be easily discovered. As a result, even when it is difficult to do so by only measuring the specific resistance value, etc., the conductor connection structure 1 with insufficient joint can be easily discovered using an inspection jig or the like. Therefore, a great influence on the performance of the conductor connection structure 1 can be reduced. In addition, a good-quality conductor connection structure 1 can be efficiently manufactured.

[0039] The engaging projection 41 is provided at a position that does not face the joint portion W of the backing metal 30. Thereby, when joining the wire bundle 11 and the conductor 20, it is possible to suppress the melted material from passing through the engaging projection 41 and melting away.

[0040] In the conductor connection structure 1 according to the present embodiment, the engaging projections 41 are provided one by one at the edges of the bottom wall 31 and the pair of side walls 32, respectively. By providing the engaging projections 41 at a plurality of locations, the joint state at each position can be confirmed. In addition, by providing the engaging projections 41 at the edges, an engaging portion for engaging the inspection jig can be easily formed. However, the engaging projection 41 may be provided on at least one of the bottom wall 31 and the pair of side walls 32. The number of engaging projections 41 provided on the backing metal 30 may be one or a plurality. For example, the engaging projection 41 may be provided only one on the bottom wall 31, or a plurality may be provided on the bottom wall 31. Similarly, the engaging projection 41 may be provided only one on the side wall 32, or a plurality may be provided on the side wall 32. In addition, the position where the engaging projection 41 is provided is not particularly limited, and it may be provided at the center of the bottom wall 31 or the side wall 32.

[0041] [Third Embodiment] Next, the conductor connection structure 1 according to the third embodiment will be described with reference to FIGS. 13 to 14. The conductor connection structure 1 according to the third embodiment is provided with an engagement opening 42 for engaging an inspection jig with the backing metal 30 as compared with the conductor connection structure 1 according to the first embodiment. Since other points are the same as those of the conductor connection structure 1 according to the first embodiment and the manufacturing method of the conductor connection structure 1, the description thereof will be omitted.

[0042] As shown in FIGS. 13 to 14, the backing metal 30 according to the present embodiment is provided with an engagement opening 42 for engaging an inspection jig. The engagement opening 42 penetrates from the inner surface to the outer surface of the backing metal 30 where the wire strands 11 or the conductors 20 are arranged. The engagement opening 42 can be formed by punching and processing a single plate.

[0043] By pulling or the like with an inspection jig engaged with the engagement opening 42 as exemplified in the second embodiment, it is possible to determine the quality of the joint. For example, when the backing metal 30 is not sufficiently joined to the joint W, when the inspection jig is engaged with the engagement opening 42 and pulled, the backing metal 30 floats or deforms. Therefore, by checking the joining state of the backing metal 30 with the inspection jig, it is possible to easily find the conductor connection structure 1 with insufficient joining. As a result, even in a case where it is difficult to simply measure the specific resistance value, etc., it is possible to easily find the conductor connection structure 1 with insufficient joining by using an inspection jig or the like. Therefore, a great influence on the performance of the conductor connection structure 1 can be reduced. In addition, a good-quality conductor connection structure 1 can be efficiently manufactured.

[0044] The engagement opening 42 is provided at a position not facing the joint W of the backing metal 30. Thereby, when joining the wire strands 11 and the conductors 20, it is possible to suppress the melted material from passing through the engagement opening 42 and melting away.

[0045] In the conductor connection structure 1 according to the present embodiment, the engaging openings 42 are respectively provided one by one in the bottom wall 31 and the pair of side walls 32. By providing the engaging openings 42 at a plurality of locations, the joining state at each position can be confirmed. However, the engaging opening 42 may be provided in at least one of the bottom wall 31 and the pair of side walls 32. The number of the engaging openings 42 provided in the backing plate 30 may be one or a plurality. For example, only one engaging opening 42 may be provided in the bottom wall 31, or a plurality of engaging openings 42 may be provided in the bottom wall 31. Similarly, only one engaging opening 42 may be provided in the side wall 32, or a plurality of engaging openings 42 may be provided in the side wall 32. Further, the position where the engaging opening 42 is provided is not particularly limited, and it may be provided at the edge of the bottom wall 31 or the side wall 32.

[0046] In the present embodiment, the engaging opening 42 is a through hole, and the through hole has a circular shape. The diameter of the engaging opening 42 is preferably 1 mm or more and 1.5 mm or more. By setting the diameter of the engaging opening 42 within such a range, the inspection jig can be easily engaged with the engaging opening 42. Note that the shape of the opening is not particularly limited, and it may be an ellipse, a square, a rectangle, a polygon such as a star shape, a teardrop shape, or an irregular shape.

[0047] [Fourth Embodiment] Next, the conductor connection structure 1 according to the fourth embodiment will be described with reference to FIGS. 15 to 16. The conductor connection structure 1 according to the fourth embodiment is provided with a visual opening 43 in the backing plate 30 so that the joint W can be visually confirmed from the outside of the backing plate 30 as compared with the conductor connection structure 1 according to the first embodiment. Since the other points are the same as those of the conductor connection structure 1 and the manufacturing method of the conductor connection structure 1 according to the first embodiment, the description thereof will be omitted.

[0048] As shown in FIGS. 15 to 16, the backing metal 30 according to the present embodiment is provided with a visual opening 43 through which the joint portion W can be visually confirmed from the outside of the backing metal 30. The visual opening 43 penetrates from the inner surface to the outer surface of the backing metal 30 where the strand bundle 11 or the conductor 20 is disposed. The visual opening 43 can be formed by punching a single plate.

[0049] The engagement opening 42 is provided at a position facing the joint portion W of the backing metal 30. Thereby, the joint state of the joint portion W can be visually confirmed through the visual opening 43. For example, when the melt has entered the visual opening 43 or the joint portion W is melted, it can be determined that the joint is good. On the other hand, when the melt has not entered the visual opening 43 and the joint portion W is not melted, it can be determined that the joint is not good. Thereby, even when it is difficult only to measure the specific resistance value or the like, the conductor connection structure 1 with insufficient connection can be easily found by using an inspection jig or the like. Therefore, a great influence on the performance of the conductor connection structure 1 can be reduced. In addition, a good conductor connection structure 1 can be efficiently manufactured.

[0050] In the conductor connection structure 1 according to the present embodiment, a plurality of visual openings 43 are provided on the bottom wall 31 and the pair of side walls 32, respectively, and are arranged along the joint portion W. By providing the visual openings 43 at a plurality of locations, the joint state at each position can be visually confirmed. Further, in the conductor connection structure 1 according to the present embodiment, on the bottom wall 31, the visual openings 43 arranged side by side inclined in the width direction Y with respect to the length direction X are arranged side by side along the joint portion W in the width direction Y. Further, on the side wall 32, the visual openings 43 arranged side by side inclined in the height direction Z with respect to the length direction X are arranged side by side along the joint portion W in the height direction Z.

[0051] For example, when irradiating a laser from above the backing metal 30 to weld the end of the wire bundle 11 and the end of the conductor 20, the irradiation energy attenuates above the wire bundle 11 and the conductor 20 and tends not to reach the bottom wall 31. Therefore, melting is large above the wire bundle 11 and the conductor 20 and small below. If the irradiation energy of the laser is small, the wire bundle 11 and the conductor 20 may not melt up to the bottom wall 31 of the backing metal 30, and there is a risk of poor welding. However, by providing the visual inspection openings 43 arranged in the height direction Z in the backing metal 30, it is possible to easily confirm how much the irradiation energy of the laser is insufficient, and for example, the irradiation intensity of the laser can be adjusted.

[0052] However, the visual inspection opening 43 only needs to be provided in at least one of the bottom wall 31 and the pair of side walls 32. The number of visual inspection openings 43 provided in the backing metal 30 may be one or a plurality. For example, the visual inspection opening 43 may be provided only one on the bottom wall 31, or a plurality may be provided on the bottom wall 31. Similarly, the visual inspection opening 43 may be provided only one on the side wall 32, or a plurality may be provided on the side wall 32.

[0053] In the present embodiment, the visual inspection opening 43 is a through hole, and the through hole has a circular shape. The diameter of the visual inspection opening 43 is preferably 1.5 times or more and 2 times or less the diameter of the wire 13. By setting the diameter of the visual inspection opening 43 within such a range, visual inspection is easy and it is possible to suppress the melted metal from melting and falling out of the visual inspection opening 43. Further, the diameter of the visual inspection opening 43 is preferably 0.4 mm or more and 0.9 mm or more. Note that the shape of the visual inspection opening 43 is not particularly limited, and may be an ellipse, a square, a rectangle, a polygon such as a star shape, a teardrop shape, or an irregular shape.

[0054] For example, the visual opening 43 may be an elliptical visual opening 44 as shown in FIGS. 17 to 18, for example. Specifically, in the bottom wall 31, visual openings 44 extending obliquely with respect to the length direction X in the width direction Y are arranged along the joint W in the width direction Y. Further, in the side wall 32, visual openings 44 extending obliquely with respect to the length direction X in the height direction Z are arranged along the joint W in the height direction Z. Even with such a shape, the joint state of the joint W can be visually confirmed through the visual opening 44.

[0055] In addition, in the conductor connection structure 1 according to the fourth embodiment, an engaging protrusion 41 as described in the second embodiment or an engaging opening 42 as described in the third embodiment may be provided.

[0056] [Fifth Embodiment] Next, the conductor connection structure 1 according to the fifth embodiment will be described with reference to FIGS. 19 to 20. The conductor connection structure 1 according to the fifth embodiment is provided with a cover 33 on the backing plate 30 as compared with the conductor connection structure 1 according to the first embodiment, and the periphery of the joint W is surrounded by the backing plate 30 and the cover 33. Since other points are the same as those of the conductor connection structure 1 according to the first embodiment and the manufacturing method of the conductor connection structure 1, the description thereof will be omitted.

[0057] The cover 33 is connected to the upper end of the side wall 32 so as to be openable and closable. In the present embodiment, the bottom wall 31, the side wall 32, and the cover 33 are formed of a single metal plate and are integrally and continuously formed. The connection portion between the side wall 32 and the cover 33 is provided with a portion thinner than the side wall 32 or the cover 33 around the connection portion in order to facilitate the opening and closing of the cover 33. The open end of the cover 33 is closed so as to contact the upper end of the side wall 32 which is one end of the backing plate 30.

[0058] In the conductor connection structure 1 according to the present embodiment, a cover 33 is provided on the backing plate 30. Therefore, even when the individual wires 13 are frayed and protrude, the cover 33 can be closed to accommodate the individual wires 13 within the space formed by the backing plate 30 and the cover 33. As a result, the protrusion of the individual wires 13 can be suppressed, and thus a short circuit in the circuit caused by the individual wires 13 can be suppressed. Further, even when covering the wire bundle 11, the conductor 20, and the backing plate 30 with a covering material such as an insulating tape or a tube to insulate them, it is possible to suppress the protruding individual wires 13 from piercing through the covering material, so that the thickness of the covering material can be reduced.

[0059] The conductor connection structure 1 according to the present embodiment can be formed by closing the cover 33 after the joining process. Note that after closing the cover 33, one end of the cover 33 and one end of the backing plate 30 do not have to be joined by welding or the like. As a result, the protrusion of the individual wires 13 can be suppressed, and the manufacturing process can be simplified.

[0060] Note that the cover 33 may be a separate part. For example, it may include a top plate and a pair of side walls connected to the ends of the top plate, and the cover 33 may be placed over the backing plate 30 including the bottom wall 31 and the side walls 32. In this case, the cover 33 may be formed of metal or may be formed of resin.

[0061] Note that in the conductor connection structure 1 according to the fifth embodiment, a visual opening 43 as described in the fourth embodiment may be provided.

[0062] As described in the above embodiment, the conductor connection structure 1 according to the present disclosure includes a wire bundle 11 in which a plurality of individual wires 13 are bundled, an electric wire 10 having an end portion of the wire bundle 11 formed in a plate shape, a conductor 20 having an end portion formed in a plate shape, and a backing plate 30 formed of a metal plate-like member. The end portion of the wire bundle 11 is joined in a state of being abutted against the end portion of the conductor 20. The backing plate 30 is in contact with and surrounds the joint portion W along the joint portion W between the wire bundle 11 and the conductor 20. The backing plate 30 is joined via the joint portion W.

[0063] In addition, the manufacturing method of the conductor connection structure 1 according to the present disclosure includes a step of preparing a wire bundle 11 in which a plurality of strands 13 are bundled, a wire 10 having an end portion formed in a plate shape, a conductor 20 having an end portion formed in a plate shape, and a backing metal 30 formed of a metal plate member. The manufacturing method of the conductor connection structure 1 includes a step of butting the end portion of the wire bundle 11 and the end portion of the conductor 20, joining them in a state where the end portion of the wire bundle 11 and the end portion of the conductor 20 are surrounded by the backing metal 30, and joining the backing metal 30 via a joint portion W.

[0064] According to the conductor connection structure 1 according to the present embodiment, the wire bundle 11 having an end portion formed in a plate shape and the conductor 20 having an end portion formed in a plate shape are joined in a butted state. Therefore, miniaturization in the height direction Z can be achieved as compared with the case where the wire bundle 11 and the conductor 20 are overlapped and joined. Further, in the conductor connection structure 1 according to the present embodiment, even when the metal is excessively melted, the end portion of the wire bundle 11 and the end portion of the conductor 20 can be joined within the backing metal 30. Therefore, by melting the metal under slightly stronger conditions so that insufficient melting of the metal does not occur, poor joining due to insufficient melting can be suppressed.

[0065] Therefore, according to the conductor connection structure 1 and the manufacturing method of the conductor connection structure 1 according to the present embodiment, it is possible to reduce the melting away of the butted joint portion.

[0066] An engaging protrusion 41 or an engaging opening 42 for engaging an inspection jig may be provided at a position not facing the joint portion W of the backing metal 30. Thereby, the joint state of the backing metal 30 can be confirmed only by hooking the inspection jig on the engaging protrusion 41 or the engaging opening 42. Therefore, even when it is difficult to measure only the specific resistance value, etc., it is possible to easily detect the conductor connection structure 1 with insufficient joining using an inspection jig or the like.

[0067] At a position facing the joint W of the backing metal 30, a visual opening 43 may be provided that allows the joint W to be visually confirmed from the outside of the backing metal 30. Thereby, the joint state of the joint W can be visually confirmed through the visual opening 43. Therefore, even in a case where it is difficult to do only by measuring the specific resistance value, etc., the conductor connection structure 1 with insufficient joint can be easily discovered visually.

[0068] A cover 33 may be provided on the backing metal 30, and the periphery of the joint W may be surrounded by the backing metal 30 and the cover 33. Since the periphery of the joint W can be surrounded by the backing metal 30 and the cover 33, even when the strands 13 are frayed and protrude, the strands 13 can be accommodated in the space formed by the backing metal 30 and the cover 33. Thereby, since the protrusion of the strands 13 can be suppressed, a short circuit of the circuit due to the strands 13 can be suppressed.

[0069] In the joining step, the end of the strand bundle 11 and the end of the conductor 20 may be joined by a laser. In a joining method such as laser welding, high energy can be concentrated in a narrow range and the control is also easy. Also, in laser welding, since the laser can penetrate deep into the metal, the metal can be melted deeply.

[0070] As described above, the present embodiment has been explained, but the present embodiment is not limited to these, and various modifications are possible within the scope of the gist of the present embodiment.

Explanation of Reference Numerals

[0071] 1 Conductor connection structure 10 Electric wire 11 Strand bundle 13 Strand 14 End face 20 Conductor 21 End face 30 Backing metal 33 Cover 41 Engagement protrusion 42 Engagement opening 43 Visual opening 44 Visual opening W Junction

Claims

1. An electric wire including a stranded wire bundle in which a plurality of individual wires are bundled, the end of the stranded wire bundle being formed in a plate shape, A conductor having an end formed in a plate shape, A backing metal formed of a metal plate member, Comprising, The end of the stranded wire bundle is joined in a butted state with respect to the end of the conductor, The backing metal surrounds the joint portion in a state of being in contact with and along the joint portion between the stranded wire bundle and the conductor, The backing metal is joined via the joint portion, a conductor connection structure.

2. The conductor connection structure according to claim 1, wherein an engaging protrusion or an engaging opening for engaging an inspection jig is provided at a position not facing the joint portion of the backing metal.

3. The conductor connection structure according to claim 1 or 2, wherein a visual opening for visually confirming the joint portion from the outside of the backing metal is provided at a position facing the joint portion of the backing metal.

4. The conductor connection structure according to claim 1 or 2, wherein a cover is provided on the backing metal, and the periphery of the joint portion is surrounded by the backing metal and the cover.

5. A step of preparing an electric wire including a stranded wire bundle in which a plurality of individual wires are bundled, the end of the stranded wire bundle being formed in a plate shape, a conductor having an end formed in a plate shape, and a backing metal formed of a metal plate member; A step of butting the end of the stranded wire bundle and the end of the conductor, joining the end of the stranded wire bundle and the end of the conductor in a state surrounded by the backing metal, and joining the backing metal via the joint portion; A method for manufacturing a conductor connection structure, including.

6. The method for manufacturing a conductor connection structure according to claim 5, wherein in the joining step, the end of the stranded wire bundle and the end of the conductor are joined by a laser.

Images