Manufacturing method for flexible busbars

Abstract

This invention provides a method for manufacturing flexible busbars that can stabilize quality and improve manufacturing efficiency, even with complex shapes. [Solution] Multiple conductive material foils 1 are laminated (see Figure 1(a)). Both sides (upper fixed portion 2, lower fixed portion 3) of the laminated multiple conductive material foils 1 are fixed to form upper fixed portion 2, lower fixed portion 3 and non-fixed portion 4 on the multiple conductive material foils 1 (see Figure 1(c)). Then, a flexible busbar (5) of a predetermined shape is cut out from the multiple conductive material foils 1 on which the upper fixed portion 2, lower fixed portion 3 and non-fixed portion 4 have been formed (see Figures 1(c) and (d)).

Description

Technical Field

[0001] The present invention relates to a method for manufacturing a flexible bus bar.

Background Art

[0002] Generally, when connecting members capable of conducting electricity (for example, batteries mounted on electric vehicles, hybrid cars, etc.), it is known to use a flexible bus bar. As such a flexible bus bar, for example, the one described in Patent Document 1 is known. The flexible bus bar described in Patent Document 1 is manufactured by laminating and fixing conductive material foils made of a thin and flexible metal such as copper, which has been cut out in a predetermined shape in advance.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Here, the above-described conventional method for manufacturing a flexible bus bar will be described in more detail with reference to FIG. 5.

[0005] When manufacturing a flexible bus bar 100 as shown in FIG. 5(c), first, a vertically long rectangular (straight shape) conductive material foil 101 made of a thin and flexible metal such as copper as shown in FIG. 5(a) is prepared. Then, from the prepared conductive material foil 101, a complex shape (non-straight shape) indicated by a broken line S100 in FIG. 5(a) is cut out using a wire or the like. Thereby, a flexible bus bar piece 102 having a complex shape (non-straight shape) as shown in FIG. 5(b) is manufactured.

[0006] Thus, as shown in Figure 5(b), multiple flexible busbar pieces 102 manufactured in this manner are stacked so that their upper end faces 102a and lower end faces 102b are aligned. In this state, the upper end face 102a side of the flexible busbar piece 102 shown in Figure 5(b) is fixed to form an upper fixed portion 103 as shown in Figure 5(c), and the lower end face 102b side of the flexible busbar piece 102 shown in Figure 5(b) is fixed to form a lower fixed portion 104 as shown in Figure 5(c). As a result, a flexible busbar 100 is manufactured in which a non-fixed portion 105 is formed between the upper fixed portion 103 and the lower fixed portion 104, as shown in Figure 5(c). This non-fixed portion 105 is flexible.

[0007] However, in this manufacturing method, as shown in Figure 5(b), multiple flexible busbar pieces are stacked so that their upper end faces 102a and lower end faces 102b are aligned. This presented a problem in that misalignment could occur during the stacking process. Consequently, the quality of the flexible busbar 100 shown in Figure 5(c) was unstable, potentially leading to a decrease in manufacturing efficiency. This problem was particularly pronounced when manufacturing flexible busbar pieces 102 with complex shapes (non-straight shapes) as shown in Figure 5(b).

[0008] Therefore, in view of the above problems, the present invention aims to provide a method for manufacturing flexible busbars that can stabilize quality and improve manufacturing efficiency, even if they have a complex shape. [Means for solving the problem]

[0009] The object of the present invention described above is achieved by the following means. The reference numerals in parentheses indicate the embodiments described later, but the present invention is not limited thereto.

[0010] The method for manufacturing a flexible busbar according to claim 1 includes the steps of laminating a plurality of conductive materials (conductive material foil 1) (see Figure 1(a)), The process involves fixing both sides (upper fixing portion 2, lower fixing portion 3) of the laminated plurality of conductive materials (conductive material foil 1) to form a fixed portion (upper fixing portion 2, lower fixing portion 3) and an unfixed portion (4) on the plurality of conductive materials (conductive material foil 1) (see Figure 1(c)), The present invention is characterized by comprising the step of cutting out a flexible busbar (5) of a predetermined shape from the plurality of conductive materials (conductive material foil 1) on which the fixed portion (upper fixed portion 2, lower fixed portion 3) and the non-fixed portion (4) are formed (see Figures 1(c) and (d)).

[0011] The method for manufacturing a flexible busbar according to claim 2 includes the step of laminating a plurality of conductive materials (conductive material foil 1A) (see Figure 4(a)), The process involves fixing both sides (upper fixing portion 2, lower fixing portion 3) of the laminated plurality of conductive materials (conductive material foil 1A) to form a fixed portion (upper fixing portion 2, lower fixing portion 3) and an unfixed portion (4) on the plurality of conductive materials (conductive material foil 1A) (see Figure 4(c)), The present invention is characterized by comprising the step of cutting out a plurality of flexible busbars (5) of a predetermined shape from a plurality of conductive materials (conductive material foil 1A) on which the fixed portion (upper fixed portion 2, lower fixed portion 3) and the non-fixed portion (4) are formed (see Figures 4(c), (d)).

[0012] The method for manufacturing a flexible busbar according to claim 3 is characterized in that, in the method for manufacturing a flexible busbar according to claim 1 or 2, the non-fixed portion (4) of the cut-out flexible busbar (5) of the predetermined shape is formed in a rectangular shape and the lengths of the diagonals (4a, 4b) are the same (see Figure 2(a-2)).

[0013] The method for manufacturing a flexible busbar according to claim 4 is characterized in that, in the method for manufacturing a flexible busbar according to claim 1 or 2, the cut-out flexible busbar (5) of the predetermined shape has protrusions (upper protrusion 2b, lower protrusion 3b) or recesses formed thereon.

[0014] The method for manufacturing a flexible busbar according to claim 5 is characterized in that, in the method for manufacturing a flexible busbar according to claim 1 or 2, the fixing portion (upper fixing portion 2, lower fixing portion 3) is formed by heat welding. [Effects of the Invention]

[0015] Next, the effects of the present invention will be described with reference to the reference numerals in the drawings. Note that the reference numerals in parentheses are those of embodiments described later, but the present invention is not limited thereto.

[0016] According to the invention of claims 1 and 2, since a flexible busbar (5) of a predetermined shape is cut from a plurality of conductive materials (conductive material foils 1, 1A) having fixed parts (upper fixed part 2, lower fixed part 3) and non-fixed parts (4), there is no need to prepare complex shapes (non-straight shapes) as in conventional manufacturing methods. Therefore, it is possible to prevent misalignment when laminating.

[0017] Therefore, according to the present invention, even with complex shapes, it is possible to stabilize quality and improve manufacturing efficiency.

[0018] Furthermore, according to the invention of claim 2, multiple pieces can be cut out at once, thus reducing manufacturing man-hours.

[0019] According to the invention of claim 3, the non-fixed portion (4) of the flexible busbar (5) of a predetermined shape is formed in a rectangular shape, and the lengths of its diagonals (4a, 4b) are the same (see Figure 2(a-2)). Therefore, when the flexible busbar (5) is bent for use, no difference in distance occurs when it is bent, regardless of the direction in which it is bent, and thus no wrinkles are formed in the non-fixed portion (4) due to bending.

[0020] According to the invention according to claim 4, it is possible to easily cope with the formation of protrusions (upper protrusion 2b, lower protrusion 3b) or recesses, and to stabilize the quality and improve the manufacturing efficiency.

[0021] According to the invention according to claim 5, when heat is applied to the flexible bus bar (5) used in solder or the like, there is no possibility of melting. Further, there is no possibility that the resistance value required for the flexible bus bar (5) cannot be obtained due to the influence of members used in solder or the like.

Brief Description of Drawings

[0022] [Figure 1] (a) to (d) are explanatory diagrams for explaining a method for manufacturing a flexible bus bar according to an embodiment of the present invention. [Figure 2] (a-1) shows a front view of a flexible bus bar manufactured by the manufacturing method according to the embodiment, (a-2) is a front view of the non-fixed portion of the flexible bus bar shown in (a-1) extracted, (b-1) shows a front view of a flexible bus bar manufactured by a conventional manufacturing method, and (b-2) is a front view of the non-fixed portion of the flexible bus bar shown in (b-1) extracted. [Figure 3] It is a front view showing a flexible bus bar provided with protrusions on the flexible bus bar manufactured by the manufacturing method according to the embodiment. [Figure 4] It is an explanatory diagram for explaining a method for manufacturing a plurality of flexible bus bars by the manufacturing method according to the embodiment. [Figure 5] (a) to (c) are explanatory diagrams for explaining a conventional method for manufacturing a flexible bus bar.

Mode for Carrying Out the Invention

[0023] Hereinafter, a method for manufacturing a flexible bus bar according to an embodiment of the present invention will be specifically described with reference to the drawings. In the following description, when indicating the up-down, left-right directions, it refers to the up-down, left-right as viewed from the front shown in the drawing.

[0024] <Explanation of the manufacturing method for flexible busbars> The manufacturing method for flexible busbars according to this embodiment can stabilize quality and improve manufacturing efficiency, even for complex shapes. Specifically, they are manufactured as follows.

[0025] First, a stack of multiple thin, flexible conductive material foils 1 made of a metal such as copper, arranged in a long rectangular shape (straight shape), is prepared, as shown in Figure 1(a). At this stage, it is assumed that a complex shape (non-straight shape) will be cut out from the stacked conductive material foils 1, as shown in Figure 1(b), indicated by the dashed line S1. In this assumed cutting, it is assumed that the right side surface 1a of the stacked conductive material foils 1 will be parallel to the right long side S1a of the complex shape (non-straight shape) indicated by the dashed line S1 in Figure 1(b), and that the left side surface 1b of the stacked conductive material foils 1 will be parallel to the left long side S1b of the complex shape (non-straight shape) indicated by the dashed line S1 in Figure 1(b). Note that at this stage, this is only an assumption and no cutting has been done yet.

[0026] Next, the upper end surface 1c side of the multiple laminated conductive material foils 1 shown in Figure 1(b) is fixed by heat welding to form an upper fixed portion 2 as shown in Figure 1(c), and the lower end surface 1d side of the multiple laminated conductive material foils 1 shown in Figure 1(b) is fixed by heat welding to form a lower fixed portion 3 as shown in Figure 1(c). As a result, a non-fixed portion 4 is formed between the upper fixed portion 2 and the lower fixed portion 3, as shown in Figure 1(c). This non-fixed portion 4 is flexible.

[0027] Next, in this state, the material is cut along the dashed line S1 shown in Figure 1(c), which was intended to be cut out, using a wire, press, or laser. This results in the production of a flexible busbar 5 as shown in Figure 1(d).

[0028] Therefore, as explained above, by fixing both ends of the multiple laminated conductive material foils 1 (the upper fixing part 2 and the lower fixing part 3 shown in Figure 1(c)) and then cutting them out, it becomes unnecessary to assemble pieces with complex shapes (non-straight shapes) as in conventional manufacturing methods. As a result, it is possible to avoid the possibility of misalignment occurring during lamination, as is the case with conventional manufacturing methods.

[0029] Therefore, according to this embodiment, the quality of the flexible busbar 5 shown in Figure 1(d) can be stabilized, and furthermore, manufacturing efficiency can be improved.

[0030] Therefore, according to this embodiment, even with complex shapes, it is possible to stabilize quality and improve manufacturing efficiency.

[0031] Furthermore, in this embodiment, when manufacturing the flexible busbar 5 as shown in Figure 2(a-1), the non-fixed portion 4 is cut out in a rectangular shape as shown in Figure 2(a-2). Specifically, the right side surface 1a of the multiple laminated conductive material foils 1 shown in Figure 1(b) is parallel to the right long side S1a of the complex shape (non-straight shape) shown by the dashed line S1 in Figure 1(b), and the left side surface 1b of the multiple laminated conductive material foils 1 is parallel to the left long side S1b of the complex shape (non-straight shape) shown by the dashed line S1 in Figure 1(b). As a result, the non-fixed portion 4 can be cut out in a rectangular shape as shown in Figure 2(a-2). In this non-fixed portion 4, as shown in Figure 2(a-2), the lengths of the diagonals 4a and 4b are the same. In this way, when the flexible busbar 5 is bent for use, as shown in Figure 2(a-2), the lengths of diagonals 4a and 4b are the same, so no matter which direction it is bent, there will be no difference in the distance when bent. Therefore, no wrinkles will form in the non-fixed portion 4 due to bending.

[0032] In other words, as explained above, the conventional flexible busbar 100 is as shown in Figure 2(b-1). As shown in Figure 2(b-1), the non-fixed portion 105 of this flexible busbar 100 is a parallelogram as shown in Figure 2(b-2). And, as shown in Figure 2(b-2), this parallelogram has diagonals 105a and 105b of different lengths. Therefore, when the flexible busbar 100 is bent for use, as shown in Figure 2(a-2), the bending will differ depending on the direction of bending because the diagonals 105a and 105b are of different lengths. Consequently, a difference in distance is likely to occur when bent, and wrinkles may form in the non-fixed portion 105 due to bending. If such wrinkles occur, it will not only look bad, but it may also cause problems when connecting electrically conductive components (for example, batteries installed in electric vehicles or hybrid cars), such as being unable to connect them properly due to size incompatibility.

[0033] However, as in this embodiment, if the lengths of the diagonals 4a and 4b of the non-fixed portion 4 are the same, the above-mentioned problems will not occur.

[0034] Furthermore, by forming a non-fixed portion 4 such that the lengths of diagonals 4a and 4b are the same, as described above, the vertical length L1 of the non-fixed portion 4 shown in Figure 2(a-1) can be made longer than the vertical length L2 of the non-fixed portion 105 shown in Figure 2(b-1). This makes it possible to increase the flexibility (range of motion) of the flexible busbar 5 compared to the conventional flexible busbar 100.

[0035] Furthermore, since the amount of laminated conductive material foil 1 remaining after cutting out the flexible busbar 5 from the laminated conductive material foil 1 is less than in conventional methods, material loss can be reduced.

[0036] Incidentally, the flexible busbar 5 manufactured as described above is used with an upper bolt hole 2a passing through the upper fixing portion 2 and a lower bolt hole 3a passing through the lower fixing portion 3, as shown in Figure 3. That is, bolts (not shown) are inserted into the upper bolt hole 2a and the lower bolt hole 3a to connect electrically conductive members (for example, batteries mounted on electric vehicles or hybrid cars) using the flexible busbar 5 shown in Figure 3. However, if bolts (not shown) are inserted through the upper bolt hole 2a and the lower bolt hole 3a to fix them, a load will be placed on the upper fixing portion 2 and the lower fixing portion 3 shown in Figure 3, potentially causing them to be crushed and unable to connect electrically conductive members. Therefore, to avoid this situation, an upper projection 2b may be provided on the upper end surface of the upper fixing portion 2 and a lower projection 3b on the lower end surface of the lower fixing portion 3, as shown in Figure 3, so that the upper fixing portion 2 and the lower fixing portion 3 can be hooked onto the above-mentioned members. In addition to the upper projection 2b and lower projection 3b, recesses consisting of concave notches can also be provided.

[0037] Thus, in order to provide such upper protrusions 2b and lower protrusions 3b, or recesses not shown, conventional manufacturing methods require that when cutting from the conductive material foil 101 shown in Figure 5(a) using a wire or the like, the upper protrusions 2b and lower protrusions 3b, or recesses not shown, be provided during the cutting process. Therefore, when stacking multiple cut pieces, misalignment may occur when attempting to align the upper protrusions 2b and lower protrusions 3b, or recesses not shown.

[0038] However, in this embodiment, since the ends of the multiple laminated conductive material foils 1 (the upper fixing portion 2 and the lower fixing portion 3 shown in Figure 1(c)) can be fixed together and then cut out to provide the upper protrusions 2b and the lower protrusions 3b, or recesses not shown, there is no possibility of the above-mentioned misalignment occurring.

[0039] Therefore, even when upper protrusions 2b and lower protrusions 3b as shown in Figure 3, or recesses not shown, are provided, it is possible to easily accommodate these, stabilize quality, and improve manufacturing efficiency.

[0040] <Explanation of variations> It should be noted that the shapes and other features shown in this embodiment are merely examples, and various modifications and changes are possible within the scope of the gist of the present invention as described in the claims. For example, although this embodiment shows an example of manufacturing one flexible busbar 5, it is also possible to manufacture multiple flexible busbars 5 together using the manufacturing method described above. This will be explained in detail with reference to Figure 4.

[0041] As shown in Figure 4(a), a multi-layered structure of multiple thin, flexible conductive material foils 1A, shaped like a horizontal rectangle (straight shape) and made of a metal such as copper, is prepared. At this stage, as shown in Figure 4(b), it is assumed that multiple complex shapes (non-straight shapes) indicated by the dashed line S1 in Figure 4(b) will be cut out from the multi-layered conductive material foil 1A. In this cutting assumption, it is assumed that the right side surface 1Aa of the multi-layered conductive material foil 1A is parallel to the right long side S1a of the complex shape (non-straight shape) indicated by the dashed line S1 in Figure 4(b), and the left side surface 1Ab of the multi-layered conductive material foil 1A is parallel to the left long side S1b of the complex shape (non-straight shape) indicated by the dashed line S1 in Figure 4(b). Note that at this stage, this is only an assumption and no cutting has been done yet.

[0042] Next, the upper end surface 1Ac side of the multiple laminated conductive material foils 1A shown in Figure 4(b) is fixed by heat welding to form the upper fixed portion 2 as shown in Figure 4(c), and the lower end surface 1Ad side of the multiple laminated conductive material foils 1 shown in Figure 4(b) is fixed by heat welding to form the lower fixed portion 3 as shown in Figure 4(c). As a result, a non-fixed portion 4 is formed between the upper fixed portion 2 and the lower fixed portion 3, as shown in Figure 4(c). This non-fixed portion 4 is flexible.

[0043] Next, in this state, the material is cut along the multiple dashed lines S1 shown in Figure 4(c), which were intended to be cut out, using a wire, press, or laser. This results in the production of multiple flexible busbars 5 as shown in Figure 4(d).

[0044] Therefore, even with this method, as described above, it is possible to stabilize quality and improve manufacturing efficiency, even with complex shapes.

[0045] Furthermore, because multiple pieces can be cut at once, manufacturing time can be reduced.

[0046] Furthermore, although this embodiment shows an example in which the upper fixing portion 2 and the lower fixing portion 3 are formed by heat welding, the method is not limited to this, and they may also be formed using solder or the like. However, heat welding is preferred. This is because if solder or the like is used, the solder used in the solder may melt when heat is applied to the flexible busbar 5, and furthermore, the resistance value required for the flexible busbar 5 may not be obtained due to the influence of the materials used in the solder or the like. For this reason, heat welding is preferred. [Explanation of Symbols]

[0047] 1.1A Conductive Material Foil (Conductive Material) 2 Upper fixing part (fixing part) 2b Upper process (protrusion) 3. Lower fixing part (fixing part) 3b Lower protrusion (protrusion) 4 Non-adhesive part 4a, 4b Diagonal 5 Flexible busbars

Claims

1. A process of laminating multiple conductive materials, A step of fixing both sides of the stacked plurality of conductive materials to form a fixed portion and an unfixed portion in the plurality of conductive materials, A method for manufacturing a flexible busbar, comprising the step of cutting out a flexible busbar of a predetermined shape from a plurality of conductive materials on which the fixed portion and the non-fixed portion are formed.

2. A process of laminating multiple conductive materials, A step of fixing both sides of the stacked plurality of conductive materials to form a fixed portion and an unfixed portion in the plurality of conductive materials, A method for manufacturing a flexible busbar, comprising the step of cutting out a plurality of flexible busbars of a predetermined shape from a plurality of conductive materials on which the fixed portion and the non-fixed portion are formed.

3. A method for manufacturing a flexible busbar according to claim 1 or 2, wherein the non-fixed portion of the cut-out flexible busbar of the predetermined shape is formed in a rectangular shape and the diagonal lengths are the same.

4. The method for manufacturing a flexible bus bar according to claim 1 or 2, wherein a projection or recess is formed on the cut-out flexible bus bar of the predetermined shape.

5. The method for manufacturing a flexible bus bar according to claim 1 or 2, wherein the fixed portion is formed by heat welding.

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