Electric connection box

Abstract

To provide an electric connection box which is lightweight and capable of dissipating heat of an electronic component.SOLUTION: An electric connection box 1 is connected to an external bus bar 2. The electric connection box 1 comprises an electronic component, which is heated by electrification, and a heat dissipation member 30. The electronic component includes a terminal part 22 connected to the external bus bar 2, and the heat dissipation member 30 includes an overlapped part 31, which is disposed while being overlapped with the terminal part 22 in a first direction, and an expanded part 32 which is disposed while being expanded outside of the terminal part 22 in a view in the first direction. The external bus bar 2, the terminal part 22 and the heat dissipation member 30 are collectively coupled by a bolt B1.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Conventionally, an electrical connection box described in JP 2022-191739 A (Patent Document 1 below) is known. The electrical connection box described in Patent Document 1 is mounted on a vehicle such as an electric vehicle or a hybrid vehicle, and distributes power supplied from a battery to various devices. The electrical connection box includes a bus bar electrically connected to the battery and a fuse directly connected to the bus bar. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-191739 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the above configuration, the bus bar is long in the front-rear direction and has a large surface area. This allows heat generated by the fuse to be transferred to the bus bar and efficiently dissipated from the bus bar to the lower case and the outside air. However, in the above configuration, the weight of the electrical junction box is likely to increase due to the long bus bar. [Means for solving the problem]

[0005] The electrical junction box of the present disclosure is an electrical junction box connected to an external bus bar, and comprises: an electronic component that generates heat when electricity is passed through it; and a heat dissipation member, wherein the electronic component has a terminal portion connected to the external bus bar, and the heat dissipation member comprises an overlapping portion arranged overlapping the terminal portion in a first direction, and an extension portion arranged to protrude outside the terminal portion when viewed in the first direction, and the external bus bar, the terminal portion, and the heat dissipation member are fastened together with bolts. Effect of the Invention

[0006] According to the present disclosure, it is possible to provide an electrical junction box that is lightweight and capable of dissipating heat from electronic components. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is an exploded perspective view of the electrical junction box according to the first embodiment. [Diagram 2] FIG. 2 is a plan view of the electrical junction box according to the first embodiment. [Diagram 3] FIG. 3 is a cross-sectional view taken along line AA of FIG. [Figure 4] FIG. 4 is a plan view of the electrical junction box excluding the upper case according to the first embodiment. [Diagram 5] FIG. 5 is an exploded perspective view of the electrical junction box excluding the upper case according to the first embodiment. [Figure 6] FIG. 6 is a bottom view of the heat dissipation member and the fuse according to the first embodiment. [Figure 7] FIG. 7 is a perspective view of a heat dissipation member according to a modified example of the first embodiment. [Figure 8] FIG. 8 is a plan view of the electrical junction box according to the second embodiment. [Figure 9] FIG. 9 is a cross-sectional view taken along line BB of FIG. [Figure 10] FIG. 10 is a cross-sectional view taken along line CC of FIG. [Figure 11] FIG. 11 is an exploded perspective view of the electric junction box according to the second embodiment. [Figure 12]FIG. 12 is a plan view of the heat dissipation member and the fuse according to the second embodiment. [Figure 13] FIG. 13 is a perspective view of a heat dissipation member and a fuse according to the second embodiment. [Figure 14] FIG. 14 is a perspective view of a heat dissipation member and a fuse according to a modified example of the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] [Description of the embodiments of the present disclosure] First, embodiments of the present disclosure will be listed and described. [1] The electrical junction box disclosed herein is an electrical junction box connected to an external bus bar, and includes an electronic component that generates heat when electricity is passed through it, and a heat dissipation member, wherein the electronic component has a terminal portion connected to the external bus bar, and the heat dissipation member includes an overlapping portion arranged overlapping the terminal portion in a first direction, and an extension portion arranged to protrude outside the terminal portion when viewed in the first direction, and the external bus bar, the terminal portion, and the heat dissipation member are fastened together with bolts.

[0009] With this configuration, the heat generated by the electronic components can be dissipated to the outside by the extension of the heat dissipation member. Also, since there is no need to provide a long bus bar between the external bus bar and the electronic components in order to cool the electronic components, the weight of the electrical junction box can be reduced.

[0010] [2] In the above item [1], it is preferable that the extension portion has a plate shape, and an area of ​​the extension portion as viewed in a thickness direction of the extension portion is larger than an area of ​​the terminal portion as viewed in the first direction.

[0011] With this configuration, it becomes easier to improve the heat dissipation efficiency of the extension portion.

[0012] [3] In the above [1] or [2], the heat dissipation member is preferably made of metal.

[0013] With this configuration, it becomes easier to increase the thermal conductivity and strength of the heat dissipation member.

[0014] [4] It is preferable that the electrical junction box of any one of [1] to [3] above further comprises a case in which the electronic component is held, and the heat dissipation member is disposed in close proximity to the case.

[0015] With this configuration, heat can be easily dissipated from the heat dissipation member to the outside via the case.

[0016] [5] In the above [4], it is preferable that the case comprises a lower case and an upper case arranged above the lower case, the heat dissipation member is arranged in the lower case, and the extension portion has a portion extending in a direction perpendicular to the first direction.

[0017] According to this configuration, by increasing the size of the portion of the extension portion that is disposed adjacent to the lower case, heat can be easily transferred from the extension portion to the lower case. Also, the height of the electrical junction box can be easily reduced.

[0018] [6] In the above [4], it is preferable that the case comprises a lower case and an upper case arranged above the lower case, the heat dissipation member is arranged in the upper case, and the extension portion has a portion extending in the first direction.

[0019] With this configuration, for example, if the electrical junction box is arranged so that the upper case is located above the lower case, the rising air current around the extension portion makes it easier to transfer heat from the extension portion to the upper case.

[0020] [7] In any one of the above [1] to [6], it is preferable that the overlapping portion is not disposed between the terminal portion and the external bus bar.

[0021] With this configuration, the contact resistance between the terminal portion and the external bus bar can be reduced, compared to a case in which the overlapping portion is disposed between the terminal portion and the external bus bar.

[0022] [8] It is preferable that any one of the electrical junction boxes [1] to [7] above is an electrical junction box connected to a detection circuit, the detection circuit detects the state of a battery electrically connected to the external bus bar, and the heat dissipation member has a connection portion connected to the detection circuit.

[0023] With this configuration, there is no need to provide a new member for connecting the detection circuit and the external bus bar.

[0024] [9] In any one of the above [1] to [8], it is preferable that at least a portion of the heat dissipation member is covered with a covering material, and that the covering material has a higher emissivity than the heat dissipation member.

[0025] With this configuration, heat can be easily dissipated to the outside by radiation from the heat dissipation member.

[0026]

[10] In any one of the above [1] to [9], it is preferable that the heat dissipation member has a plate shape, and a thickness of the heat dissipation member is smaller than a thickness of the external bus bar.

[0027] With this configuration, the weight of the electrical junction box can be reduced.

[0028] [Details of the embodiment of the present disclosure] The following describes embodiments of the present disclosure. The present disclosure is not limited to these examples, but is shown by the claims, and is intended to include all modifications within the meaning and scope of the claims. In each drawing, for convenience of explanation, some of the configurations may be exaggerated or simplified. In addition, the dimensional ratios of each part may differ in each drawing. In this specification, "orthogonal" does not only mean strictly orthogonal, but also includes roughly orthogonal within the range in which the action and effect of this embodiment are achieved.

[0029] In addition, "facing" in this specification refers to surfaces or members facing each other, and includes not only cases where they are completely facing each other, but also cases where they are partially facing each other. In addition, "facing" in this specification includes both cases where a member other than the two parts is interposed between the two parts, and cases where nothing is interposed between the two parts.

[0030] <Embodiment 1> A first embodiment of the present disclosure will be described with reference to Figures 1 to 7. In the following description, the direction indicated by the arrow Z is the upward direction, the direction indicated by the arrow X is the forward direction, and the direction indicated by the arrow Y is the leftward direction. Note that, for multiple identical members, only some of the members may be labeled with reference numerals, and the reference numerals of the other members may be omitted.

[0031] (Electrical junction box 1) The electric junction box 1 of the present embodiment is mounted on a vehicle such as an electric vehicle or a hybrid vehicle, and is disposed in a power supply path from a battery to a load such as a motor. As shown in FIG. 2, the electric junction box 1 is connected to external bus bars 2 and 3. The external bus bars 2 and 3 are for electrically connecting the electric junction box 1 to a device (including a battery) provided outside the electric junction box 1. The external bus bars 2 and 3 have a portion disposed outside the electric junction box 1. The external bus bar 2 is electrically connected to a battery. The external bus bar 3 is electrically connected to a load. The external bus bars 2 and 3 are connected to the electric junction box 1 by bolt fastening. As shown in FIG. 1, the electric junction box 1 includes a case 10, a fuse 20 (an example of an electronic component), a heat dissipation member 30, a first bus bar 41, a second bus bar 42, a third bus bar 43, and relays 50 and 60.

[0032] (Case 10) The case 10 is made of synthetic resin, and includes a lower case 11 and an upper case 12. The upper case 12 is assembled by being placed on top of the lower case 11. When connecting the external bus bars 2, 3 and the electrical junction box 1 by bolt fastening, if the bolts B1, B3 are fastened from above, the upper case 12 is arranged above the lower case 11, as shown in Figures 1 to 3. Below, the configuration and arrangement of each member of the electrical junction box 1 will be described assuming that the upper case 12 is arranged above the lower case 11.

[0033] (Lower Case 11) As shown in Figs. 4 and 5, the lower case 11 is formed in a tray shape that is long in the front-rear direction. The fuse 20, the heat dissipation member 30, the first bus bar 41, the second bus bar 42, the third bus bar 43, and the relay 50 are arranged in the lower case 11. As shown in Fig. 5, a fuse arrangement section 11A in which the fuse 20 is arranged is formed in the front part of the lower case 11. The fuse arrangement section 11A is a recess capable of accommodating the main body 21 of the fuse 20. As shown in Figs. 3 and 5, fastening sections N1 and N2 capable of fastening bolts B1 and B2 are provided on both the front and rear sides of the fuse arrangement section 11A. A facing surface 11B extending in the horizontal direction is formed in front of the fuse arrangement section 11A. The facing surface 11B is a surface that faces the heat dissipation member 30 in the up-down direction. 5, a mounting surface 11C on which the relay 50 is mounted and a positioning portion 11D for positioning the relay 50 are formed in the rear portion of the lower case 11. The positioning portion 11D is a recess recessed from a side wall portion 11E rising upward from the right edge of the mounting surface 11C. A fastening portion N3 to which a bolt B3 can be fastened is provided in the rear end portion of the lower case 11. The mounting surface 11C of the lower case 11 may further be provided with a fixing portion (not shown) for fixing the relay 50.

[0034] (Upper Case 12) As shown in FIG. 1, the upper case 12 is lid-shaped. The upper case 12 includes a first busbar accommodating portion 12A for accommodating the first busbar 41, a second busbar accommodating portion 12B for accommodating the second busbar 42, and a third busbar accommodating portion 12C for accommodating the third busbar 43. The busbar accommodating portions 12A, 12B, and 12C are provided in a groove shape that fits the shape of the busbars 41, 42, and 43, respectively. A window portion 12D is provided at the front end of the upper case 12 for connecting the terminal portion 22 of the fuse 20 and the external busbar 2. As shown in FIG. 1 and FIG. 3, a facing portion 12E facing the heat dissipation member 30 in the up-down direction is formed in front of the window portion 12D. The facing portion 12E is in the shape of a plate extending in the horizontal direction.

[0035] 1, upper case 12 may have a relay mounting portion 12F in which relay 60 is mounted. Relay mounting portion 12F is formed by utilizing the space between second bus bar 42 and third bus bar 43, for example.

[0036] (Huse 20) As shown in Fig. 5, the fuse 20 includes a main body 21 and two terminals 22 extending from both front and rear ends of the main body 21. The main body 21 is block-shaped. The terminals 22 are made of metal. The terminals 22 are plate-shaped and thin in the vertical direction. The terminals 22 have insertion holes 22A through which the bolts B1 and B2 are inserted.

[0037] The relay 50 is a large mechanical relay through which a high current is applied from a battery. The relay 50 includes a main body 51 and a partition wall 52 extending from the right surface of the main body 51. The main body 51 is block-shaped. As shown in FIG. 4, the partition wall 52 engages with a positioning portion 11D of the lower case 11, thereby positioning the relay 50 relative to the lower case 11. Two nut-shaped terminals (not shown) are formed on the right surface of the main body 51, and bolts B4 and B5 can be fastened to these terminals. The two terminals of the relay 50 are disposed across the partition wall 52.

[0038] 5, the first bus bar 41, the second bus bar 42, and the third bus bar 43 are each formed by stamping and bending a metal plate. The metal plate material constituting the second bus bar 42 and the third bus bar 43 is thinner than the metal plate material constituting the first bus bar 41. The first bus bar 41 includes a relay connection portion 41A connected to a terminal portion of the relay 50, and an external connection portion 41B connected to the external bus bar 3. The relay connection portion 41A has an insertion hole 41A1 through which the bolt B4 is inserted. The external connection portion 41B has an insertion hole 41B1 through which the bolt B3 is inserted.

[0039] The second bus bar 42 includes a fuse connection portion 42A connected to the terminal portion 22 of the fuse 20, a relay connection portion 42B connected to the terminal portion of the relay 50, an intermediate portion 42C connecting the fuse connection portion 42A and the relay connection portion 42B, and an extension portion 42D extending forward from the intermediate portion 42C beyond the fuse connection portion 42A. The fuse connection portion 42A and the relay connection portion 42B have insertion holes 42A1 and 42B1 through which the bolts B2 and B5 are inserted, respectively. The fuse connection portion 42A extends leftward from the front end portion of the intermediate portion 42C. The intermediate portion 42C has a plate shape extending in the front-rear direction. The extension portion 42D is disposed utilizing the space to the right of the fuse 20, and has the function of releasing heat transferred from the fuse 20 and the relay 50 to the second bus bar 42 to the case 10.

[0040] The third bus bar 43 includes a fuse connection portion 43A connected to the terminal portion 22 of the fuse 20, a relay connection portion 43B connected to the terminal portion of the relay 50, a bent portion 43C connecting the fuse connection portion 43A and the relay connection portion 43B, and an extension portion 43D extending forward from the bent portion 43C beyond the fuse connection portion 43A. The fuse connection portion 43A and the relay connection portion 43B are arranged to overlap with the fuse connection portion 42A and the relay connection portion 42B, respectively. The fuse connection portion 43A and the relay connection portion 43B have insertion holes 43A1 and 43B1 through which the bolts B2 and B5 are inserted, respectively. The fuse connection portion 43A extends rightward from the front end portion of the bent portion 43C. The bent portion 43C is formed by bending a metal plate material. Extension portion 43D is disposed utilizing the space to the left of fuse 20, and has the function of dissipating heat transferred from fuse 20 and relay 50 to third bus bar 43 to case 10.

[0041] As described above, the second bus bar 42 and the third bus bar 43 are both members that constitute a conductive path between the fuse 20 and the relay 50, but are arranged with a space between them so as to branch off from each other. This differs from the present embodiment in that the surface area of ​​the bus bars (i.e., the second bus bar 42 and the third bus bar 43) that connect the fuse 20 and the relay 50 can be made larger than when the fuse 20 and the relay 50 are connected by a single bus bar. This allows the fuse 20 and the relay 50 to dissipate heat efficiently. In addition, by making the thickness of the second bus bar 42 and the third bus bar 43 about half the thickness of the first bus bar 41, for example, the heat dissipation efficiency of the fuse 20 and the relay 50 can be increased while suppressing an increase in the weight of the electrical junction box 1.

[0042] (Heat dissipation member 30) The heat dissipation member 30 has a plate shape. In this embodiment, the heat dissipation member 30 is made of a metal such as copper, a copper alloy, aluminum, or an aluminum alloy. As shown in FIG. 6, the heat dissipation member 30 includes an overlapping portion 31 arranged overlapping the terminal portion 22 in the vertical direction (one example of a first direction), and an extension portion 32 arranged protruding from the outside of the terminal portion 22 when viewed from the vertical direction. The area of ​​the extension portion 32 when viewed from the thickness direction (vertical direction) of the extension portion 32 is, for example, larger than the area of ​​the terminal portion 22 when viewed from the vertical direction. Note that the area of ​​the extension portion 32 when viewed from the thickness direction (vertical direction) of the extension portion 32 may be equal to the area of ​​the terminal portion 22 when viewed from the vertical direction, or may be smaller than the area of ​​the terminal portion 22 when viewed from the vertical direction. The overlapping portion 31 has a through hole 31A through which a bolt B1 is inserted. As shown in FIG. 3, the external bus bar 2, the terminal portion 22, and the heat dissipation member 30 are fastened together by the bolt B1.

[0043] Since the heat dissipation member 30 has the extension portion 32 arranged protruding from the terminal portion 22, the surface area of ​​the portion connected to the terminal portion 22 and capable of dissipating heat from the terminal portion 22 can be increased compared to a case where the heat dissipation member 30 is not provided. Therefore, the heat generated by the fuse 20 can be easily dissipated to the outside. Even if the thickness of the heat dissipation member 30 is thin, the surface area of ​​the heat dissipation member 30 can be increased by increasing the dimension of the extension portion 32 in the direction perpendicular to the thickness direction. Therefore, for example, compared to a case where a long bus bar is provided between the external bus bar 2 and the fuse 20, the weight of the electric junction box 1 can be suppressed while the heat dissipation efficiency of the fuse 20 can be improved.

[0044] 3, the overlapping portion 31 is disposed below the terminal portion 22. The external busbar 2 is bolted to the terminal portion 22 in a state where it is overlapped above the terminal portion 22. In other words, the overlapping portion 31 is not disposed between the external busbar 2 and the terminal portion 22. This makes it possible to reduce the contact resistance between the external busbar 2 and the terminal portion 22, compared to when the overlapping portion is disposed between the external busbar 2 and the terminal portion 22.

[0045] The heat dissipation member 30 is disposed in close proximity to the case 10. In particular, the distance between the heat dissipation member 30 and the case 10 in the thickness direction (vertical direction) of the heat dissipation member 30 is preferably 5 mm or less, and more preferably 2 mm or less. It is most preferable that the heat dissipation member 30 and the case 10 are in contact with each other in the thickness direction (vertical direction) of the heat dissipation member 30. By disposing the heat dissipation member 30 and the case 10 in close proximity, heat can be easily dissipated from the heat dissipation member 30 to the outside via the case 10.

[0046] As shown in Fig. 3, the extension portion 32 is in the shape of a plate extending horizontally (an example of a direction perpendicular to the first direction). The extension portion 32 is disposed adjacent to the opposing surface 11B of the lower case 11. The extension portion 32 faces the opposing surface 11B in the vertical direction. The extension portion 32 is also disposed adjacent to the opposing portion 12E of the upper case 12. The extension portion 32 faces the opposing portion 12E in the vertical direction. This makes it easier for heat to escape from the extension portion 32 to the lower case 11 and the upper case 12.

[0047] As shown in FIG. 7, the heat dissipation member 30 of this embodiment may include a connection portion 33 connected to a detection circuit (not shown). Here, the detection circuit has a function of detecting the state of the battery. For example, the detection circuit has a function of detecting voltage and a function of detecting leakage current. The connection portion 33 may be in a form extending in the form of a tab from a portion of the heat dissipation member 30 in the vicinity of the overlapping portion 31. By providing the connection portion 33 to the heat dissipation member 30, it is not necessary to provide a new member for connecting the detection circuit and the external bus bar 2.

[0048] (Effects of the First Embodiment) (1-1) The electrical connection box 1 in embodiment 1 is an electrical connection box 1 connected to an external bus bar 2, and includes an electronic component (fuse 20) that generates heat when electricity is passed through it, and a heat dissipation member 30. The electronic component has a terminal portion 22 connected to the external bus bar 2. The heat dissipation member 30 includes an overlapping portion 31 arranged overlapping the terminal portion 22 in a first direction (up and down direction) and an extension portion 32 arranged protruding outside the terminal portion 22 when viewed in the first direction. The external bus bar 2, the terminal portion 22, and the heat dissipation member 30 are fastened together by a bolt B1.

[0049] According to this configuration, heat generated in the electronic components can be dissipated to the outside by the extension portion 32 of the heat dissipation member 30. Also, since there is no need to provide a long bus bar between the external bus bar 2 and the electronic components in order to cool the electronic components, it becomes easier to reduce the weight of the electrical junction box 1.

[0050] (1-2) In the first embodiment, the extension portion 32 has a plate shape, and the area of ​​the extension portion 32 as viewed in the thickness direction of the extension portion 32 is larger than the area of ​​the terminal portion 22 as viewed in the first direction.

[0051] With such a configuration, the heat dissipation efficiency of the extension portion 32 can be easily improved.

[0052] (1-3) In the first embodiment, the heat dissipation member 30 is made of metal.

[0053] With such a configuration, the thermal conductivity and strength of the heat dissipation member 30 can be easily increased.

[0054] (1-4) The electrical junction box 1 according to the first embodiment further includes a case 10 for holding electronic components, and the heat dissipation member 30 is disposed adjacent to the case 10.

[0055] With this configuration, heat can be easily dissipated from the heat dissipation member 30 to the outside via the case 10.

[0056] (1-5) In embodiment 1, case 10 includes a lower case 11 and an upper case 12 arranged above lower case 11, heat dissipation member 30 is disposed in lower case 11, and extension portion 32 has a portion extending in a direction perpendicular to the first direction (horizontal direction).

[0057] According to such a configuration, by increasing the size of the portion of the extension portion 32 that is disposed adjacent to the lower case 11, heat can be easily transferred from the extension portion 32 to the lower case 11. In addition, the height of the electrical junction box 1 can be easily reduced.

[0058] (1-6) In the first embodiment, the overlapping portion 31 is not disposed between the terminal portion 22 and the external bus bar 2.

[0059] With this configuration, the contact resistance between terminal portion 22 and external bus bar 2 can be made smaller than when overlapping portion 31 is disposed between terminal portion 22 and external bus bar 2 .

[0060] (1-7) The electrical connection box 1 in embodiment 1 is an electrical connection box 1 connected to a detection circuit, the detection circuit detects the state of a battery electrically connected to the external busbar 2, and the heat dissipation member 30 may have a connection portion 33 connected to the detection circuit.

[0061] With this configuration, it is not necessary to provide a new member for connecting the detection circuit and the external bus bar 2.

[0062] (1-8) In the first embodiment, the heat dissipation member 30 has a plate shape, and the thickness of the heat dissipation member 30 is smaller than the thickness of the external bus bar 2.

[0063] With such a configuration, the weight of the electrical junction box 1 can be easily reduced.

[0064] <Embodiment 2> A second embodiment of the present disclosure will be described with reference to Fig. 8 to Fig. 14. An electric junction box 101 according to the second embodiment is configured substantially similarly to the first embodiment, except for the configuration of the heat dissipation member 130 and the configuration of the members around the heat dissipation member 130, and therefore, descriptions of the same members and functions and effects as those of the first embodiment may be omitted.

[0065] (Electrical junction box 101) As shown in FIG. 11, the electrical junction box 101 includes a case 110, a fuse 20, a heat dissipation member 130, a first bus bar 41, a second bus bar 42, a third bus bar 43, and relays 50 and 60.

[0066] (Case 110, Upper Case 112) The case 110 includes a lower case 11 and an upper case 112. The upper case 112 does not have the window portion 12D and the facing portion 12E of the first embodiment. The front end portion of the upper case 112 is formed with an arrangement portion 112G in which the heat dissipation member 130 is arranged.

[0067] (Heat dissipation member 130) 12 and 13, the heat dissipation member 130 is formed by bending a metal plate material. The heat dissipation member 130 includes an overlapping portion 31 similar to that of the first embodiment, and an extension portion 132 arranged protruding from the terminal portion 22 when viewed from the top-bottom direction. In this embodiment, the extension portion 132 includes a first extension portion 132A extending horizontally continuous with the overlapping portion 31, and two second extension portions 132B extending upward from both left and right side edges of the first extension portion 132A.

[0068] As shown in FIG. 10, the arrangement portion 112G of the upper case 112 is a recess that accommodates two second extension portions 132B. The second extension portion 132B is arranged close to the arrangement portion 112G. The second extension portion 132B faces the arrangement portion 112G in the left-right direction. The second extension portion 132B and the arrangement portion 112G are arranged with a small gap in the left-right direction. With this configuration, heat can be easily released from the second extension portion 132B to the arrangement portion 112G. Since the second extension portion 132B has a form that extends in the vertical direction, the heat of the second extension portion 132B can be easily transferred to the arrangement portion 112G more efficiently by the rising air current around the second extension portion 132B. The second extension portion 132B and the arrangement portion 112G may be arranged to be in close contact with each other.

[0069] Heat dissipation member 130 may be, for example, insert molded into upper case 112. Heat dissipation member 130 and upper case 112 may have a locking structure (not shown) that locks them together in the vertical direction, so that heat dissipation member 130 is held by upper case 112. Alternatively, heat dissipation member 130 may be press-fitted into upper case 112.

[0070] 8 and 11, when the heat dissipation member 130 is placed in the placement section 112G, the horizontally extending portions of the heat dissipation member 130 (the overlapping portion 31 and the first extension portion 132A) are exposed upward. As shown in FIG. 9, the overlapping portion 31 of the heat dissipation member 130 is placed above the terminal portion 22. The external bus bar 2 is bolted to the terminal portion 22 in a state where it is overlapped above the overlapping portion 31 of the heat dissipation member 130. In other words, the overlapping portion 31 of the heat dissipation member 130 is placed between the terminal portion 22 and the external bus bar 2.

[0071] (Covering material 134) The first extension portion 132A and the opposing surface 11B of the lower case 11 are disposed with a larger gap therebetween compared to the first embodiment. Therefore, it is difficult to transfer heat from the first extension portion 132A to the lower case 11. Therefore, as shown in FIG. 14, the lower surface of the first extension portion 132A may be covered with a covering material 134 having a higher emissivity than the heat dissipation member 130. For the covering material 134, for example, an insulating resin material such as polyimide, fluororesin, or epoxy resin can be used. With this configuration, even if the first extension portion 132A and the opposing surface 11B are located apart from each other as shown in FIG. 9, heat is easily released from the first extension portion 132A to the outside by radiation.

[0072] The covering material 134 is preferably formed on a portion of the extension portion 132 that is exposed to the outside air. The covering material 134 is preferably not provided on a portion of the extension portion 132 that is in contact with the external bus bar 2 or the terminal portion 22.

[0073] (Effects of the second embodiment) (2-1) In embodiment 2, case 110 comprises a lower case 11 and an upper case 112 arranged above lower case 11, heat dissipation member 130 is arranged in upper case 112, and extension portion 132 has a portion (second extension portion 132B) extending in a first direction (up-down direction).

[0074] With this configuration, for example, when the electrical connection box 101 is positioned so that the upper case 112 is located above the lower case 11, the rising air current around the extension portion 132 makes it easier to transfer heat from the extension portion 132 to the upper case 112.

[0075] (2-2) In the second embodiment, at least a portion of the heat dissipation member 130 is covered with a covering material 134 , and the covering material 134 may have a higher emissivity than the heat dissipation member 130 .

[0076] With this configuration, heat can be easily dissipated to the outside from the heat dissipation member 130 by radiation.

[0077] (Other embodiments) The above-mentioned first and second embodiments can be modified as follows: The above-mentioned first and second embodiments and the following modifications can be combined with each other to the extent that no technical contradiction occurs.

[0078] In the above first and second embodiments, the fuse 20 is exemplified as an electronic component, but the electronic component does not have to be a fuse as long as it has the property of generating heat when electricity is passed through it. The electronic component may be, for example, a relay, a resistor, a coil, a capacitor, a diode, an integrated circuit (IC), a switching element such as a field effect transistor (FET), etc.

[0079] In the first and second embodiments, the heat dissipation members 30 and 130 are made of metal, but the heat dissipation members may be made of a material other than metal.

[0080] In the above embodiments 1 and 2, the external bus bar 2 which is fastened together with the heat dissipation member 30, 130 and the terminal portion 22 was electrically connected to the battery, but the external bus bar which is fastened together with the heat dissipation member and the terminal portion may be electrically connected to a configuration other than the battery (e.g., a load). [Explanation of symbols]

[0081] 1: Electrical junction box 2,3: External busbar 10: Case 11: Lower case 11A: Fuse location 11B: Opposite surface 11C: Placement surface 11D: Positioning section 11E: Side wall part 12: Upper case 12A: First busbar housing 12B: Second bus bar housing 12C: 3rd busbar housing 12D: Window section 12E: Opposite part 12F: Relay installation section 20: Fuse 21: Main body 22:Terminal section 22A: Through hole 30: Heat dissipation material 31: Superimposition section 31A: Through hole 32: Extension 33: Connection 41: First bus bar 41A: Relay connection 41A1: Through hole 41B: External connection part 41B1: Through hole 42: 2nd bus bar 42A: Fuse connection 42A1: Through hole 42B: Relay connection 42B1: Through hole 42C: Middle part 42D: Extension part 43: 3rd bus bar 43A: Fuse connection 43A1: Through hole 43B: Relay connection 43B1: Through hole 43C: Bent part 43D: Extension 50: Relay 51: Main body 52: Partition wall 60: Relay 101: Electrical junction box 110: Case 112: Upper case 112G: Placement section 130: Heat dissipation material 132: Extension 132A: First extension 132B: Second extension 134: Covering material B1, B2, B3, B4, B5: Bolts N1,N2,N3: Fastening part

Claims

1. An electrical connection box connected to an external bus bar, An electronic component that generates heat when electricity is applied; A heat dissipation member, the electronic component has a terminal portion connected to the external bus bar, the heat dissipation member includes an overlapping portion that is arranged to overlap the terminal portion in a first direction, and an extension portion that is arranged to protrude outside the terminal portion when viewed in the first direction, the external bus bar, the terminal portion, and the heat dissipation member are fastened together by bolts.

2. The extension portion is plate-shaped, The electrical junction box according to claim 1 , wherein an area of ​​the extension portion as viewed in a thickness direction of the extension portion is larger than an area of ​​the terminal portion as viewed in the first direction.

3. 3. The electrical junction box according to claim 1, wherein the heat dissipation member is made of metal.

4. The electronic device further includes a case for holding the electronic components.

3. The electrical junction box according to claim 1, wherein the heat dissipation member is disposed adjacent to the case.

5. The case includes a lower case and an upper case disposed above the lower case, the heat dissipation member is disposed in the lower case, The electrical junction box according to claim 4 , wherein the extension portion has a portion extending in a direction perpendicular to the first direction.

6. The case includes a lower case and an upper case disposed above the lower case, the heat dissipation member is disposed in the upper case, The electrical junction box according to claim 4 , wherein the extension portion has a portion extending in the first direction.

7. 3. The electrical junction box according to claim 1, wherein the overlapping portion is not disposed between the terminal portion and the external bus bar.

8. An electrical connection box connected to the detection circuit, The detection circuit detects a state of a battery electrically connected to the external bus bar; 3. The electrical junction box according to claim 1, wherein the heat dissipation member includes a connection portion connected to the detection circuit.

9. At least a portion of the heat dissipation member is covered with a covering material, 3. The electrical junction box according to claim 1, wherein the covering material has a higher emissivity than the heat dissipating member.

10. The heat dissipation member is plate-shaped, 3. The electrical junction box according to claim 1, wherein a thickness of the heat dissipation member is smaller than a thickness of the external bus bar.

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