Electric connection box

Abstract

To provide an electric connection box capable of preventing erroneous assembly of a bus bar.SOLUTION: An electric connection box 11 comprises: a case 21 consisting of a resin material; and a first bus bar 32 and a second bus bar 33 which are stored and held in the case 21. The first bus bar 32 includes a first connection part 32a which is disposed on a bottom face in the case 21, and the second bus bar 33 includes a second connection part 33a which is connected to the first connection part 32a while being overlapped on the first connection part 32a. The first bus bar 32 includes a downward extension 32c which is bent downward and extends, and the second bus bar 33 includes a protrusion 33c which protrudes to a portion corresponding to the downward extension 32c, thereby preventing the first connection part 32a from being overlapped on the second connection part 33a.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to an electrical junction box. [Background technology]

[0002] Conventionally, an electrical junction box has been provided in, for example, a battery pack of a vehicle (see, for example, Patent Document 1). The battery pack includes a battery pack case, an electrical junction box, and a plurality of battery cells.

[0003] The electrical junction box includes a case made of a resin material and electrical circuit components housed and held within the case. The electrical circuit components include a contactor, which is a type of relay, a current sensor, a bus bar, etc. The electrical circuit components realize optimal input and output of the battery pack by monitoring the current value, temperature, etc. of the battery cells. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-125965 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in the electrical connection box described above, since it handles a large current, bus bars, which are metal plates, are often used instead of thin electric wires. The connection parts of the bus bars may be electrically connected while being overlapped on the connection parts of other bus bars. In such a case, the order in which the connection parts are overlapped is predetermined, but when assembling by hand, there is a risk of misassembly due to the incorrect order of overlapping the connection parts. In addition, in such a case, the height of the bus bar will be shifted by the plate thickness of the bus bar. This may cause, for example, poor connection between the bus bar and other electric circuit components or an excessive load on the bus bar. In addition, it is also possible to perform inspection using a camera after assembly, but since it is difficult to determine the boundary line between bus bars of the same color, there is a risk of misjudgment. In addition, the introduction cost of the camera will increase.

[0006] An object of the present disclosure is to provide an electrical junction box capable of preventing incorrect assembly of bus bars. [Means for solving the problem]

[0007] The electrical connection box disclosed herein comprises a case made of a resin material, and a first bus bar and a second bus bar housed and held within the case, the first bus bar having a first connection portion arranged on a bottom surface of the case, and the second bus bar having a second connection portion connected to the first connection portion while being overlapped on the first connection portion, wherein the first bus bar has a downward extension portion that is bent downward and extends, and the second bus bar has a protrusion portion that protrudes at a position corresponding to the downward extension portion, thereby preventing the first connection portion from being overlapped on the second connection portion. Effect of the Invention

[0008] According to the electrical junction box of the present disclosure, incorrect assembly of the bus bar can be prevented. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is an exploded perspective view of an electrical junction box according to one embodiment. [Diagram 2] FIG. 2 is a partially enlarged perspective view of the electrical junction box according to the embodiment. [Diagram 3] FIG. 3 is a partially enlarged plan view of the electrical junction box according to the embodiment. [Figure 4] FIG. 4 is a partially enlarged exploded perspective view of the electrical junction box according to one embodiment. [Diagram 5] FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. [Figure 6] FIG. 6 is a partially enlarged cross-sectional view of an electric junction box according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be listed and described. The electrical connection box of the present disclosure comprises: [1] An electrical connection box comprising: a case made of a resin material; and a first bus bar and a second bus bar housed and held within the case, wherein the first bus bar has a first connection portion arranged on a bottom surface of the case, and the second bus bar has a second connection portion connected to the first connection portion while being overlapped on the first connection portion, wherein the first bus bar has a downward extension portion bent and extending downward, and the second bus bar has a protrusion portion that protrudes at a position corresponding to the downward extension portion, thereby preventing the first connection portion from being overlapped on the second connection portion.

[0011] According to this configuration, the second bus bar has a protrusion that protrudes into a portion corresponding to the downward extension portion of the first bus bar, thereby preventing the first connection portion from being overlapped on the second connection portion, thereby preventing erroneous assembly in which the first connection portion is overlapped on the second connection portion.

[0012] [2] In the above [1], the protruding portion may have a main surface on the same plane as a main surface of the second connection portion. According to this configuration, the protrusion has a main surface on the same plane as the main surface of the second connection portion. Therefore, for example, bending or the like is not required to form the protrusion, and the protrusion can be easily formed by simply punching it out of the metal plate together with the second connection portion.

[0013] [3] In the above [1] or [2], a bolt may be provided having a male threaded shank protruding upward from a bottom surface of the case, and each of the first connection portion and the second connection portion may have a through hole through which the male threaded shank passes.

[0014] According to this configuration, the bolt has a male threaded shaft protruding upward from the bottom surface inside the case, and each of the first and second connection parts has a through hole through which the male threaded shaft passes, so that, for example, the first and second connection parts can be assembled while being positioned. Therefore, it is possible to prevent early assembly errors in which the first connection part is overlapped on the second connection part. For example, when the first and second connection parts are arranged in a portion from which the male threaded shaft part does not protrude, there is a risk that the first connection part will be overlapped on the second connection part because the first and second connection parts are arranged shifted in a direction perpendicular to the overlapping direction, but this is prevented.

[0015] [4] In any one of [1] to [3] above, the width of the second bus bar may be set wider than the width of the first bus bar, and the second connection portion may be connected to the external terminal while the external terminal is overlapped on the second connection portion.

[0016] According to this configuration, the width of the second bus bar is set wider than the width of the first bus bar to accommodate large currents. The second connection portion of the second bus bar is connected to the external terminal while the external terminal is placed on the second connection portion, so that the second connection portion is connected to the external terminal while reducing electrical resistance. In this electrical connection box, the first connection portion is prevented from being placed on the second connection portion, which effectively prevents erroneous assembly. In other words, if the external terminal is placed on the second connection portion via the first connection portion, the electrical resistance between the second connection portion and the external terminal becomes large, resulting in increased loss, but this can be avoided.

[0017] [5] An electrical connection box comprising: a case made of a resin material; and a first bus bar and a second bus bar housed and held within the case, wherein the first bus bar has a first connection portion arranged on a bottom surface of the case, and the second bus bar has a second connection portion connected to the first connection portion while being overlapped on the first connection portion, wherein the second bus bar has an upper extension portion bent upward and extending, and the first bus bar has a protrusion portion that protrudes at a position corresponding to the upper extension portion, thereby preventing the first connection portion from being overlapped on the second connection portion.

[0018] According to this configuration, the first bus bar has a protrusion that protrudes at a position corresponding to the upward extension portion of the second bus bar, thereby preventing the first connection portion from being overlapped on the second connection portion, thereby preventing erroneous assembly in which the first connection portion is overlapped on the second connection portion.

[0019] [Details of the embodiment of the present disclosure] Specific examples of the electrical connection box of the present disclosure will be described below with reference to the drawings. In each drawing, for convenience of explanation, some of the configuration may be exaggerated or simplified. In addition, the dimensional ratio of each part may differ in each drawing. In this specification, "parallel," "orthogonal," and "perfect circle" do not only mean strictly parallel, orthogonal, or perfect circle, but also include approximately parallel, orthogonal, or perfect circle within the range of the action and effect of this embodiment. Note that the present invention is not limited to these examples, but is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0020] (Configuration of electrical connection box 11) 1, the electrical junction box 11 includes a case 21, an electric circuit component 31, a bolt 41, and a nut 42. The electrical junction box 11 of this embodiment is provided in, for example, a battery pack mounted on a vehicle such as an electric vehicle. That is, the electrical junction box 11 is housed in a battery pack case together with a plurality of battery cells.

[0021] (Configuration of Case 21) The case 21 has a lower case 22 and an upper case 23. The lower case 22 and the upper case 23 are each made of a resin material. The lower case 22 is formed in a rectangular flat plate shape. The upper case 23 is configured so as to be able to be assembled above the lower case 22. The upper case 23 has a square cylindrical side wall portion 23a corresponding to the periphery of the lower case 22, and an upper wall portion 23b closing the upper end of the side wall portion 23a.

[0022] (Configuration of Electric Circuit Component 31) The electric circuit components 31 are disposed on the upper surface of the lower case 22 , which is the bottom surface inside the case 21 , and are housed and held within the case 21 .

[0023] 2 to 5, the electric circuit component 31 includes a first bus bar 32 and a second bus bar 33. The electric circuit component 31 also includes a contactor, which is a type of relay, a current sensor, a fuse, a flexible coated wire, and the like, but these are not shown in the drawings.

[0024] (Configuration of bolt 41 and nut 42) 4 and 5, the bolt 41 is provided such that the male threaded shaft portion 41a protrudes upward from the upper surface of the lower case 22. More specifically, the bolt 41 has a square columnar head portion 41b and a male threaded shaft portion 41a extending from the head portion 41b. The bolt 41 is fixed to the lower case 22 such that the male threaded shaft portion 41a protrudes upward while the head portion 41b is embedded in the lower case 22. The nut 42 can be screwed onto the male threaded shaft portion 41a.

[0025] The first bus bar 32 has a first connection portion 32a disposed on the upper surface of the lower case 22, and a first extension portion 32b extending from the first connection portion 32a. The first extension portion 32b in this embodiment has a downward extension portion 32c (see FIGS. 2, 4, and 5) that first extends from the first connection portion 32a along the longitudinal direction of the lower case 22 (to the right in FIGS. 3 and 5) and then bends downward.

[0026] The second bus bar 33 has a second connection portion 33a that is overlapped on the first connection portion 32a and connected to the first connection portion 32a, and a second extension portion 33b that extends from the second connection portion 33a. In this embodiment, the second extension portion 33b first extends from the second connection portion 33a along the short side direction (upward in FIG. 3) of the lower case 22. In other words, the second extension portion 33b extends in a direction different from the direction in which the first extension portion 32b first extends (rightward in FIG. 3) and in a direction different by 90° from the direction in which the first extension portion 32b first extends (upward in FIG. 3).

[0027] The second bus bar 33 has a protruding portion 33c that protrudes from a portion corresponding to the downward extending portion 32c of the first bus bar 32, thereby preventing the first connecting portion 32a from being overlapped on the second connecting portion 33a. The protruding portion 33c is a portion corresponding to the downward extending portion 32c, and protrudes in the direction in which the first extending portion 32b first extends (to the right in FIG. 3). Even if the first connecting portion 32a is to be overlapped on the second connecting portion 33a, the downward extending portion 32c hits the protruding portion 33c, and therefore prevents the first connecting portion 32a from being overlapped on the second connecting portion 33a. The protruding portion 33c has a main surface on the same plane as the main surface of the second connecting portion 33a. That is, the protruding portion 33c is formed by simply punching out the metal plate together with the second connecting portion 33a, without performing bending or the like.

[0028] Additionally, the first connection portion 32a and the second connection portion 33a each have through holes 32d, 33d through which the male screw shaft portion 41a penetrates. That is, the first connection portion 32a is disposed on the upper surface of the lower case 22 so that the male screw shaft portion 41a penetrates the through hole 32d. Additionally, the second connection portion 33a is disposed on the first connection portion 32a so that the male screw shaft portion 41a penetrates the through hole 32d.

[0029] The width of the second busbar 33 is set wider than the width of the first busbar 32. More specifically, the minimum width of the second busbar 33 is set wider than the minimum width of the first busbar 32. In other words, the second busbar 33 is designed to handle a larger current than the first busbar 32. In this embodiment, a contactor (not shown) which is a main side relay is connected to the tip of the second extension portion 33b of the second busbar 33. In addition, a pre-charge side relay (not shown) is connected to the tip of the first extension portion 32b of the first busbar 32.

[0030] 4, the second connection portion 33a of the second bus bar 33 is connected to the external terminal 51 while the external terminal 51 is overlapped on the second connection portion 33a. The external terminal 51 is a metal plate terminal in an electric device outside the electric junction box 11, and has a through hole 51a through which the male screw shaft portion 41a passes. The external terminal 51 is disposed on the second connection portion 33a such that the male screw shaft portion 41a passes through the through hole 51a. Then, the first connection portion 32a, the second connection portion 33a, and the external terminal 51 are electrically connected while being fastened together by a nut 42 screwed onto the male screw shaft portion 41a in an overlapped state.

[0031] Next, the operation of the electrical junction box 11 configured as above will be described. The electric circuit components 31 of the electric junction box 11 are electrically connected to other electric devices such as battery cells that are housed in the battery pack case together with the electric junction box 11. The electric circuit components 31 of the electric junction box 11 monitor the current value, temperature, etc. of the battery cells, thereby achieving optimal input and output of the battery pack.

[0032] Next, the effects of the above embodiment will be described below. (1) The second bus bar 33 has a protruding portion 33c that protrudes into a portion corresponding to the downward extending portion 32c of the first bus bar 32, thereby preventing the first connecting portion 32a from being overlapped on the second connecting portion 33a. This prevents an erroneous assembly in which the first connecting portion 32a is overlapped on the second connecting portion 33a. This prevents the heights of the first connecting portion 32a and the second connecting portion 33a from being shifted by the plate thickness. This prevents, for example, poor connection between the first bus bar 32 and the second bus bar 33 and other electric circuit components and excessive loads on the first bus bar 32 and the second bus bar 33.

[0033] (2) Since the protrusion 33c has a main surface on the same plane as the main surface of the second connection portion 33a, for example, bending or the like is not required to form the protrusion 33c, and the protrusion 33c can be easily formed by simply punching it out of a metal plate together with the second connection portion 33a.

[0034] (3) The bolt 41 has a male screw shaft portion 41a protruding upward from the upper surface of the lower case 22, which is the bottom surface inside the case 21, and each of the first connecting portion 32a and the second connecting portion 33a has a through hole 32d, 33d through which the male screw shaft portion 41a passes. Therefore, for example, the first connecting portion 32a and the second connecting portion 33a can be assembled while being positioned. Therefore, it is possible to prevent early assembly errors in which the first connecting portion 32a is overlapped on the second connecting portion 33a. That is, for example, when the first connecting portion 32a and the second connecting portion 33a are arranged in a portion from which the male screw shaft portion 41a does not protrude in advance, there is a risk that the first connecting portion 32a and the second connecting portion 33a are arranged shifted in a direction perpendicular to the overlapping direction. Therefore, the first connecting portion 32a may be overlapped on the second connecting portion 33a, but this is prevented.

[0035] (4) The width of the second bus bar 33 is set wider than the width of the first bus bar 32 to accommodate a large current. The second connection portion 33a of the second bus bar 33 is connected to the external terminal 51 while the external terminal 51 is overlapped on the second connection portion 33a, so that the second connection portion 33a is connected to the external terminal 51 while reducing electrical resistance. In such an electrical junction box 11, the first connection portion 32a is prevented from overlapping on the second connection portion 33a, which increases the effect of preventing erroneous assembly. That is, when the external terminal 51 is overlapped on the second connection portion 33a via the first connection portion 32a, the electrical resistance between the second connection portion 33a and the external terminal 51 increases, resulting in increased loss, but this can be avoided.

[0036] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the above embodiment, the first bus bar 32 has the downward extension portion 32c, and the second bus bar 33 has the protrusion portion 33c. However, this is not limited to this, and the second bus bar may have an upward extension portion, and the first bus bar may have a protrusion portion.

[0037] Specifically, it may be modified as shown in Fig. 6. An electric junction box 61 in this example includes a first bus bar 62 and a second bus bar 63. The first bus bar 62 has a first connection portion 62a that is disposed on the upper surface of the lower case 22, which is the bottom surface inside the case 21. The second bus bar 63 has a second connection portion 63a that is overlapped on the first connection portion 62a and connected to the first connection portion 62a.

[0038] The second bus bar 63 has an upper extension portion 63b that is bent and extends upward. The first bus bar 62 has a protrusion portion 62b that protrudes from a position corresponding to the upper extension portion 63b, thereby preventing the first connection portion 62a from overlapping the second connection portion 63a.

[0039] In addition, the first connection portion 62a and the second connection portion 63a in this example each have a through hole 62c, 63c through which the male screw shaft portion 41a passes, similar to the first connection portion 32a and the second connection portion 33a in the above embodiment.

[0040] Even in this manner, erroneous assembly in which the first connection portion 62a is superimposed on the second connection portion 63a is prevented, and thus the heights of the first connection portion 62a and the second connection portion 63a are prevented from shifting by the plate thickness.

[0041] In the above embodiment, the protrusion 33c has a main surface on the same plane as the main surface of the second connection portion 33a. However, this is not limited to this. For example, the protrusion 33c may be bent or otherwise configured so that the main surface is on a different plane from the main surface of the second connection portion 33a.

[0042] In the above embodiment, the bolt 41 has the male threaded shaft portion 41a protruding upward from the top surface of the lower case 22, which is the bottom surface inside the case 21. However, this is not limited to this. For example, a nut may be embedded in the lower case 22 and the bolt may be screwed into it from above.

[0043] In the above embodiment, the width of the second bus bar 33 is set to be wider than the width of the first bus bar 32, but this is not limited thereto, and may be set to be the same as the width of the first bus bar 32. Furthermore, the width of the second bus bar 33 may be set to be narrower than the width of the first bus bar 32.

[0044] In the above embodiment, the second connection portion 33a of the second bus bar 33 is connected to the external terminal 51 while the external terminal 51 is stacked on the second connection portion 33a, but this is not limited to this, and the external terminal 51 may not be connected.

[0045] In the above embodiment, the electrical connection box 11 is provided in a battery pack mounted on a vehicle such as an electric vehicle, but the present invention is not limited to this and may be provided in other devices. [Explanation of symbols]

[0046] 11 Electrical junction box 21 cases 22 Lower case 23 Upper case 23a Side wall part 23b Upper wall 31 Electrical circuit parts 32 No. 1 bus bar 32a First connection part 32b 1st extension section 32c Lower extension part 32d through hole 33 Second bus bar 33a Second connection part 33b 2nd extension section 33c protrusion 33d through hole 41 Volts 41a Male threaded shaft 41b Head 42 Nut 51 External terminal 51a Through hole 61 Electrical junction box 62 No. 1 bus bar 62a First connection part 62b Protrusion 62c through hole 63 Second bus bar 63a Second connection part 63b Extension part 63c through hole

Claims

1. An electrical connection box comprising: a case made of a resin material; and a first bus bar and a second bus bar housed and held in the case, the first bus bar having a first connection portion disposed on a bottom surface of the case, and the second bus bar having a second connection portion overlapping the first connection portion and connected to the first connection portion, the first bus bar has a downward extension portion bent and extending downward, the second bus bar has a protrusion that protrudes to a position corresponding to the lower extension portion, thereby preventing the first connection portion from overlapping the second connection portion. Electrical junction box.

2. The protrusion has a main surface on the same plane as a main surface of the second connection portion.

2. The electrical junction box according to claim 1.

3. A bolt having a male threaded shaft portion protruding upward from the bottom surface of the case, Each of the first connection portion and the second connection portion has a through hole through which the male screw shaft portion passes.

2. The electrical junction box according to claim 1.

4. The width of the second bus bar is set to be wider than the width of the first bus bar, the second connection portion is connected to the external terminal while the external terminal is placed on the second connection portion, 2. The electrical junction box according to claim 1.

5. An electrical connection box comprising: a case made of a resin material; and a first bus bar and a second bus bar housed and held in the case, the first bus bar having a first connection portion disposed on a bottom surface of the case, and the second bus bar having a second connection portion overlapping the first connection portion and connected to the first connection portion, the second bus bar has an upper extension portion that is bent and extends upward, the first bus bar has a protrusion that protrudes to a position corresponding to the upper extension portion, thereby preventing the first connection portion from overlapping the second connection portion. Electrical junction box.

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