Bus bar

Abstract

To provide a bus bar in which an insulator layer is easily peeled off.SOLUTION: A bus bar (1) according to the present invention includes a conductor (10) and an insulator layer (20) covering the conductor (10), wherein the insulator layer (20) has a recess (21) extending in a longitudinal direction of the bus bar (1), and the recess (21) is disposed in a portion of the insulator layer (20) covering a flat surface of a surface of the conductor (10).SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a busbar. [Background technology]

[0002] A bus bar is a component used to transmit power between a battery unit and an inverter in electric vehicles such as battery electric vehicles (BEVs) and hybrid electric vehicles (HEVs). In recent years, electric vehicles have been electrified not only for motor drive but also for brakes, steering, and door and window opening and closing. For example, Patent Document 1 discloses a bus bar that can be used in such electric vehicles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2022-545548 Summary of the Invention [Problem to be solved by the invention]

[0004] The busbar described above has a conductor and an insulating layer covering the conductor, and the insulating layer is suitable for maintaining the insulation of the busbar. However, when attempting to recycle the conductor of the busbar, if the insulating layer is hard or thick, or if the conductor and the insulating layer are in close contact with each other, it is difficult to peel the insulating layer from the conductor, making recycling difficult.

[0005] An object of the present invention is to provide a bus bar from which the insulating layer can be easily peeled off. [Means for solving the problem]

[0006] In order to solve the above problem, according to one aspect of the present invention, A bus bar having a conductor and an insulating layer covering the conductor, the insulator layer has a recess extending in the longitudinal direction of the bus bar, The bus bar is characterized in that the recess is disposed in a portion of the insulating layer that covers the flat surface of the conductor. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide a bus bar from which the insulating layer can be easily peeled off. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are perspective views of a bus bar according to an embodiment. [Figure 2] 2A to 2D are end views of the bus bar according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, busbars according to preferred embodiments of the present invention will be described. In this specification, when a numerical range is indicated by "to", the lower limit and upper limit are included in the numerical range.

[0010] [Busbar] Fig. 1A is a perspective view of a busbar 1. Fig. 1B shows a busbar 1 having a bent portion. As shown in Figs. 1A and 1B, the busbar 1 has a conductor 10 and an insulating layer 20 that covers the conductor 10.

[0011] The busbar 1 is manufactured, for example, by extruding a resin that will become the insulating layer 20 around the conductor 10. In the busbar 1 manufactured in this manner, the conductor 10 is covered with the insulating layer 20 over the entire longitudinal length. When the busbar 1 is to be used, for example, as shown in FIG. 1B, the insulating layers 20 are peeled off from the two ends (both ends) of the busbar 1 to expose the conductor 10. The exposed conductor 10 is electrically connected to a device to be connected, such as a battery unit or an inverter.

[0012] The shape of busbar 1 may be linear (flat) as shown in Fig. 1A, or may have curved portions as shown in Fig. 1B, depending on the position of the device to which busbar 1 is connected and the shape of the space in which busbar 1 is placed. As shown in Fig. 1B, examples of curved portions include edgewise bent portions 1a that are bent in the width direction of busbar 1 and flatwise bent portions 1b that are bent in the thickness direction of busbar 1. In this embodiment, busbar 1 is an in-vehicle busbar.

[0013] The conductor 10 and the insulating layer 20 of the bus bar 1 will be described below.

[0014] (conductor) The conductor 10 only needs to be conductive. There are no particular limitations on the size of the conductor 10, and it can be designed appropriately depending on the amount of power to be passed through it. Specifically, the thickness and width of the conductor 10 can be set appropriately depending on the amount of power to be passed through it. Furthermore, the length of the conductor 10 can be set appropriately depending on the installation location, installation conditions, etc. Examples of metals that can be used to form the conductor 10 include copper, copper alloys, aluminum, and aluminum alloys.

[0015] In this embodiment, the conductor 10 is bar-shaped, specifically a thin rectangular parallelepiped. The rectangular parallelepiped conductor 10 has six flat surfaces.

[0016] Of the six flat surfaces, four flat surfaces extend in the longitudinal direction of the conductor 10, and the remaining two flat surfaces are end faces at both ends in the longitudinal direction. Of the four flat surfaces extending in the longitudinal direction of the conductor 10, two flat surfaces extend in the width direction of the bar, and the remaining two flat surfaces extend in the thickness direction of the bar. In this embodiment, the four flat surfaces extending in the longitudinal direction are covered with an insulator layer 20. On the other hand, in this embodiment, the two end faces are not covered with an insulator layer 20.

[0017] Fig. 2A is a diagram showing an end face of busbar 1. As shown in Fig. 2A, conductor 10 has four corners 10a and four sides 10b at the end face. In this embodiment, conductor 10 is in the form of a thin plate, and the end face is in the form of an elongated rectangle.

[0018] Conductor 10 may be made of one metal plate or multiple metal plates. When conductor 10 is made of multiple metal plates, for example, thin metal plates of about 0.1 to 0.3 mm in thickness may be stacked and welded together. Conductor 10 may have a linear (flat) shape, or may not have a linear shape. As described above, conductor 10 may have curved or twisted portions depending on the position of the device to which busbar 1 is connected and the shape of the space in which busbar 1 is placed.

[0019] As shown in Fig. 1B, the conductor 10 may have a structure at its end for connection to a terminal of, for example, a battery, etc. An example of such a structure includes a bolt-receiving hole 11 for fastening with a bolt, as shown in Fig. 1B.

[0020] (insulator layer) The insulator layer 20 covers the conductor 10. The insulator layer 20 is, for example, extruded to cover the conductor 10. Alternatively, the insulator layer 20 may be cylindrical in shape and the conductor 10 may be housed inside the cylindrical insulator layer 20. In this embodiment, the insulator layer 20 covers the conductor 10 over the entire length of the conductor 10 in the longitudinal direction, and the thickness of the insulator layer 20 is approximately constant in the longitudinal direction of the insulator layer 20.

[0021] 1A and 1B, the insulator layer 20 has recesses 21 for promoting crack propagation when peeling the insulator layer. The recesses 21 are preferably designed so that when a blade such as a cutter is inserted into the recesses 21 to cut a portion of the insulator layer 20 in the thickness direction and then an attempt is made to peel the insulator layer 20 without using a special tool, the cracks can be propagated to allow the entire layer to be peeled off. Laser irradiation or the like may also be used for peeling.

[0022] In this embodiment, the recess 21 is arranged on the front side of the insulator layer 20 (the side opposite to the side that contacts the conductor 10) and extends over the entire length in the longitudinal direction of the busbar 1 (insulator layer 20). More specifically, in this embodiment, the recess 21 is arranged in the insulator layer 20 that covers the surface along the width direction of the conductor 10, which covers the surface along the width direction and the surface along the thickness direction of the conductor 10. In other words, the recess 21 is arranged in the portion of the insulator layer 20 that covers the flat surface of the conductor 10.

[0023] The depth of the recess 21 may be appropriately set so as to promote crack propagation while suppressing degradation of insulating function. From this viewpoint, the depth of the recess 21 is preferably about 0.4 to 0.6 when the thickness of the insulator layer 20 is taken as 1 (the thickness of the insulator layer 20 at the bottom of the recess 21 is about 0.4 to 0.6). In this embodiment, the depth of the recess 21 is about 0.5 when the thickness of the insulator layer 20 is taken as 1 (the thickness of the insulator layer 20 at the bottom of the recess 21 is about 0.5). More specifically, the thickness of the insulator layer 20 may be about 0.8 to 1.5 mm, and the depth of the recess 21 may be about 0.32 to 0.9 mm (the thickness of the insulator layer 20 at the bottom of the recess 21 is about 0.32 to 0.9 mm). In this embodiment, the thickness of the insulating layer 20 is about 1 mm, and the depth of the recess 21 is about 0.5 mm (the thickness of the insulating layer 20 at the bottom of the recess 21 is about 0.5 mm).

[0024] In this embodiment, as shown in FIG. 2A, the recess 21 is disposed approximately at the center in the width direction of the conductor 10. If the recess 21 is disposed at a position away from the center, stress will concentrate at the recess 21 even if the busbar 1 has an edgewise bent portion 1a as shown in FIG. 1B, causing bulging or cracking in the insulator layer 20, resulting in poor appearance and reduced insulating performance. By disposing the recess 21 approximately at the center, stress due to edgewise bending is less likely to concentrate. For example, as shown in FIG. 2A, when the length between both ends of the recess 21 in the width direction of the conductor 10 in the width direction is set to 1, the position of one end is set to 0, and the position of the other end is set to 1, the approximately center can be in the range of 0.25 to 0.75 from one end, preferably 0.375 to 0.625.

[0025] The shape of the recess 21 is not particularly limited as long as it can promote crack growth. The recess 21 may be, for example, rectangular, U-shaped, or V-shaped when viewed in cross section. In this embodiment, the recess 21 is V-shaped as shown in FIG. 2A.

[0026] The insulator layer 20 preferably has a certain degree of softness so that it can be easily peeled off. From this viewpoint, the durometer D hardness (HDD) of the insulator layer 20 measured in accordance with JIS K 7215-1986 is preferably 35 to 45. In the present embodiment, the durometer D hardness of the insulator layer 20 is about 40.

[0027] The material of the insulator layer 20 preferably has the above-mentioned durometer D hardness while exhibiting insulating properties. From this viewpoint, it is preferable to select the type of resin appropriately. From this viewpoint, the type and amount of additives (e.g., fillers) added to the resin may also be selected appropriately. Examples of materials for the insulator layer 20 include halogen-free resins. In particular, polyolefin resins and dynamically crosslinked rubber components are preferred.

[0028] From the viewpoint of exhibiting insulating performance, it is preferable that the insulator layer 20 be in contact (close contact) with the conductor 10 with as few gaps as possible. On the other hand, it is preferable that the insulator layer 20 be easily peeled off from the conductor 10 when peeling. From this viewpoint, it is preferable that the insulator layer 20 is not adhered to the conductor 10. Note that from the viewpoint of the insulator layer 20 and the conductor 10 not being adhered and being easily peeled off, it is preferable that the insulator layer 20 has the above-mentioned durometer D hardness.

[0029] (effect) In the busbar according to this embodiment, recess 21 is located approximately at the center in the width direction of conductor 10. This makes it easier to peel off insulator layer 20, and further prevents bulging or cracking in the insulator layer even if it has edgewise bent portion 1a.

[0030] [Other embodiments] 2B to 2D are end views showing examples of other embodiments of the busbar of the present invention. The present invention is not limited to the embodiment in which recesses 21 are provided on only one of two insulator layers 20 (insulator layers 20 covering the two larger side surfaces of the four side surfaces of conductor 10) that sandwich conductor 10 and cover the surfaces along the width direction of conductor 10 as shown in Fig. 2A.

[0031] As shown in FIG. 2B, recesses 21 may be arranged in both of two insulator layers 20 covering the surfaces of conductor 10 along the width direction.

[0032] 2C, two recesses 21 may be arranged side by side. By arranging two recesses 21 side by side, a portion that is easy to hold with the hand or the like is formed between the two recesses 21. By holding and pulling this portion when peeling, the insulator layer 20 can be peeled more easily. When two recesses 21 are arranged side by side, the shape of the recesses 21 when viewed in cross section is not particularly limited, but a rectangular shape is preferable from the viewpoint of ease of peeling.

[0033] 2C, the two adjacent recesses 21 may be disposed on only one of the two insulator layers 20 covering the surfaces along the width direction of the conductor 10, or may be disposed on both of them as shown in Fig. 2D. The two adjacent recesses 21 are preferably disposed approximately in the center in the width direction, as described above.

[0034] In the above embodiment and other embodiments, examples have been described in which the conductor 10 and the insulator layer 20 are in contact with each other, but the conductor 10 and the insulator layer 20 may not be in contact with each other, and a fire-resistant layer may be disposed between the conductor 10 and the insulator layer 20. The fire-resistant layer is, for example, a layer formed of a fire-resistant tape such as mica tape.

[0035] (effect) The bus bars according to other embodiments shown in FIGS. 2B to 2D also have the same effects as the bus bar 1 according to the above-described embodiment. [Industrial Applicability]

[0036] The busbar according to the embodiment of the present invention is useful, for example, for efficient recycling of conductors, since the insulating layer can be easily peeled off. [Explanation of symbols]

[0037] 1 busbar 1a Edgewise bent part 1b Flatwise bend 10 Conductors 10a corner Side 10b 11 Bolt receiving hole 20 Insulator layer 21 Recess

Claims

1. A bus bar having a conductor and an insulating layer covering the conductor, the insulator layer has a recess extending in the longitudinal direction of the bus bar, The busbar, wherein the recess is disposed in a portion of the insulator layer that covers a flat surface of the conductor.

2. 2. The bus bar according to claim 1, wherein the recess is disposed at a substantially central position in a width direction of the conductor.

3. 2. The bus bar according to claim 1, wherein the insulating layer has two of the recesses arranged side by side.

4. 2. The bus bar according to claim 1, wherein the conductor and the insulating layer are not bonded to each other.

5. 2. The bus bar according to claim 1, wherein the insulator layer has a durometer D hardness of 35 to 45 as measured in accordance with JIS K 7215-1986.

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