Electrical junction box

Abstract

An electrical junction box (10) comprises: equipment 11 that includes a busbar 31 and a fuse 33; and a case 12 for accommodating the equipment 11. The electrical junction box 10 comprises a mounting section 20 for mounting the fuse 33 within the case 12. A part of the mounting section 20 is a holder 21 that retains the fuse 33, and a separate part of the mounting section 20 is a support section 22 that can come into contact with the busbar 31 to position the busbar 31.

Description

Electrical junction box

[0001] The present invention relates to an electrical junction box. This application claims priority based on Japanese Patent Application No. 2025-049314 filed on March 25, 2025, and incorporates all the content described in said Japanese application by reference.

[0002] Patent Document 1 discloses an electrical junction box mounted on an automobile. The electrical junction box accommodates various components such as relays, fuses, and busbars, and enables these components to be unitized.

[0003] Japanese Unexamined Patent Publication No. 2002-300712

[0004] The electrical junction box includes components including a busbar and a fuse, and a case for accommodating said components. The electrical junction box has a mounting portion for mounting said fuse inside said case. A part of said mounting portion is a holder that holds said fuse, and another part of said mounting portion is a support portion that can contact said busbar and position said busbar.

[0005] Fig. 1 is an exploded perspective view showing an example of an electrical junction box. Fig. 2 is a perspective view of components. Fig. 3 is a perspective view of a mounting portion. Fig. 4 is an explanatory view showing a mounting portion and a busbar. Fig. 5 is a perspective view of a mounting portion and a busbar. Fig. 6 is a perspective view of a mounting portion and a second case. Fig. 7 is an exploded perspective view showing a second embodiment of an electrical junction box. Fig. 8 is a perspective view of a mounting portion and a busbar. Fig. 9 is a perspective view of a mounting portion and a busbar. Fig. 10 is an exploded perspective view showing a set of a mounting block and a busbar shown in Fig. 9.

[0006] <Problem to be Solved by the Invention> In recent years, in-vehicle control systems have become more sophisticated and complex in order to improve the performance of automobiles. Along with this, the number of components accommodated in an electrical junction box mounted on an automobile may increase. In order to improve the efficiency of assembling the electrical junction box, a reduction in the number of components constituting the electrical junction box is required.

[0007] In the invention disclosed in Patent Document 1, the mounting portion for mounting the fuse is composed of a single junction box, which only functions as a base for holding the fuse. Therefore, the present invention aims to provide an electrical junction box that enables a reduction in the number of components.

[0008] <Effects of the Invention> The number of parts in the electrical junction box is reduced, and the electrical junction box contributes to increased assembly efficiency.

[0009] <Outline of Embodiments of the Invention> Hereinafter, an outline of embodiments of the present invention will be listed and described. (1) An electrical junction box according to an embodiment of the present invention comprises equipment including a busbar and a fuse, and a case for housing the equipment. The electrical junction box has a mounting portion for mounting the fuse inside the case. A part of the mounting portion (first part) is a holder for holding the fuse, and another part of the mounting portion (second part) is a support portion that can contact the busbar and position the busbar.

[0010] The aforementioned electrical junction box has a mounting section inside the case for installing a fuse. This mounting section functions not only as a fuse holder but also as a busbar support. The holder and support are integrated into a single component, reducing the number of parts in the electrical junction box. The busbar is plate-shaped and elastically deforms when subjected to external force. This elastic deformation is suppressed by the support section.

[0011] (2) In the electrical junction box described in (1), another part of the mounting portion (third part) is an insulating wall located next to the busbar to be insulated. The mounting portion also functions as an insulating wall. The holder, support portion and insulating wall are configured as a single integrated component, which reduces the number of components in the electrical junction box.

[0012] (3) In the electrical junction box described in (1) or (2) above, the equipment includes electric wires. In the electrical junction box, another part of the mounting portion (fourth part) is a fixing portion that positions the electric wires along the mounting portion. The mounting portion also functions as a fixing portion that positions the electric wires. The holder, support portion and fixing portion are configured as a single integrated part, which reduces the number of parts in the electrical junction box.

[0013] (4) In any one of the electrical junction boxes described in (1) to (3) above, another part of the mounting portion (fifth part) is a column that can contact a part of the case and restricts the displacement of that part. The mounting portion also functions as a column that restricts the displacement of a part of the case. The holder, support portion and column portion are configured as a single integrated part, which reduces the number of parts in the electrical junction box.

[0014] <Details of Embodiments of the Invention> Hereinafter, details of embodiments of the present disclosure will be described with reference to the drawings. At least some of the embodiments described below may be arbitrarily combined. [Overall Configuration of Electrical Connection Box] Figure 1 is an exploded perspective view showing an example of an electrical connection box. The electrical connection box 10 shown in Figure 1 is a device mounted on an automobile. The electrical connection box 10 houses various equipment 11 such as a busbar 31, electric wires 32, fuses 33, and relays 34, and these equipment 11 are unitized. In other words, the electrical connection box 10 has equipment 11 and a case 12 for housing the equipment 11. The case 12 has a first case 13 and a second case 14. Figure 1 shows the first case 13 and the second case 14 in a simplified manner.

[0015] Case 12 is made of resin. The first case 13 and the second case 14 are joined together by fastening members such as bolts. The equipment 11 is housed between the first case 13 and the second case 14. Figure 2 is a perspective view of the equipment 11, viewed from the opposite direction to Figure 1 (the second case 14 side).

[0016] The electrical junction box 10 has a mounting section 20 for mounting a fuse 33 inside the case 12. The mounting section 20 is included in the equipment 11 housed in the case 12. Figure 3 is a perspective view of the mounting section 20, showing the equipment 11 unit shown in Figure 2 with the busbar 31, wires 32, fuse 33, and relay 34 removed.

[0017] The mounting portion 20 is made of resin. In this embodiment, the mounting portion 20 is a separate component from the first case 13 and the second case 14, and is attached to either the first case 13 or the second case 14. The mounting portion 20 is a single plate-shaped block made of resin, and in the following description, the mounting portion 20 will be referred to as the "mounting block 20".

[0018] The mounting block 20 has a holder 21 for holding the fuse 33. The fuse 33 is, for example, a high-current ceramic fuse. The holder 21 has a box shape that opens towards the first case 13 in order to house the fuse 33. The electrical connection box 10 has a fuse cover 16 (see Figure 1), and the fuse cover 16 mainly covers the fuse 33 held in the holder 21 of the mounting portion 20 from the first case 13 side.

[0019] Figure 4 is an explanatory diagram showing the mounting block 20 and the bus bar 31. The mounting block 20 has a support portion 22 that can contact the bus bar 31 and position the bus bar 31. In this embodiment, the mounting block 20 has two support portions 22A and 22B. The first support portion 22A has a columnar shape that protrudes from the bottom wall 211 of the holder 21. The second support portion 22B has a columnar shape that protrudes from a portion 212 (see Figure 3) near the bottom wall 211.

[0020] As shown in Figure 4, the first support portion 22A and the second support portion 22B contact the plate portion 311 of a plate-shaped busbar 31 (hereinafter referred to as "busbar 31A") which has a bent portion. The busbar 31A is connected to another busbar (not shown) and has a function for heat dissipation. The busbar 31A becomes a heat dissipation member of the equipment 11 of the electrical connection box 10. As shown in Figure 1, a heat dissipation pad 36 is attached to the plate portion 311 of the busbar 31A. An opening 141 is provided in the second case 14 to expose the heat dissipation pad 36. The busbar 31A can dissipate heat to an external device (not shown) via the heat dissipation pad 36.

[0021] The electrical junction box 10 is positioned on top of the external device such that the busbar 31A contacts a part of the external device via the heat dissipation pad 36. As a result, the busbar 31A receives a reaction force from the external device and is pushed toward the holder 21. Therefore, the support portion 22 contacts and supports the plate portion 311 of the busbar 31A to prevent it from elastically deforming and moving away due to the reaction force.

[0022] As shown in Figure 3, the holder 21 and the support portion 22 are configured as a single integrated part. In other words, a part of the mounting block 20 (first part) is the holder 21 that holds the fuse 33, and another part of the mounting block 20 (second part) is the support portion 22 that positions the bus bar 31.

[0023] In this embodiment (see Figure 2), busbars 31B and 31C, which are separate from busbar 31A, are also for heat dissipation. The mounting block 20 further has a third support portion 22C that protrudes from a part of it (a part of the insulating wall 23 which will be described later) (see Figure 3). The third support portion 22C is capable of contacting the busbar 31C (see Figures 2 and 5) and positions the busbar 31C.

[0024] Figure 5 is a perspective view of the mounting block 20 and the two busbars 31C and 31D. Figure 5 is a view of the mounting block 20 and the like in Figure 4 from a different angle. The busbars 31C and 31D shown in Figure 5 are different from the busbar 31A shown in Figure 4. The mounting block 20 has an insulating wall 23. The insulating wall 23 is a wall portion that extends in a planar manner from a part of the holder 21. Multiple through-holes are provided in the insulating wall 23.

[0025] The insulating wall 23 is located next to the bus bar 31 to be insulated. In the configuration shown in Figure 5, the bus bar 31 consists of two bus bars 31C and 31D. The two bus bars 31C and 31D are positioned close together in some areas, resulting in a large potential difference. Therefore, the insulating wall 23 is interposed between bus bar 31C and bus bar 31D. The insulating wall 23 provides electrical insulation between bus bars 31C and 31D.

[0026] As shown in Figure 3, the holder 21, the support portion 22, and the insulating wall 23 are configured as a single integrated component. In other words, another part (the third part) of the mounting block 20 is the insulating wall 23 located next to the bus bar 31 that is to be insulated.

[0027] In Figure 2, the equipment 11 includes a busbar 31, a fuse 33, and a relay 34, as well as a plurality of wires 32. The busbar 31, fuse 33, and relay 34 are fixed to a part of the case 12 or the mounting block 20 by fastening members such as bolts. The wires 32 extend from terminals 37 connected to the busbar 31 and are provided along the bottom wall 211 and a part of the insulating wall 23 of the holder 21. The connectors 38 at the ends of the wires 32 are connected to the connector holder 39 of the equipment 11.

[0028] The mounting block 20 has a plurality of fixing parts 24 for positioning the electric wire 32. In other words, the electric wire 32 is fixed by the fixing parts 24 of the mounting block 20. As shown in Figures 2 and 3, the fixing parts 24 are provided protruding from the bottom wall 211 and the insulating wall 23 of the holder 21, respectively. The fixing parts 24 position the electric wire 32 along the mounting block 20. The plurality of fixing parts 24 position the electric wire 32 along the bottom wall 211 and the insulating wall 23 of the holder 21.

[0029] Each fixing part 24 (see Figure 3) has a pair of claws 241 that grip the electric wire 32, and a wall 242 surrounding these claws 241. The electric wire 32 is held in place by the pair of claws 241, preventing it from falling out of the fixing part 24. The wall 242 is provided with a slit for the electric wire 32, which is held in place by the claws 241, to pass through. With this configuration of the fixing part 24, the electric wire 32 is positioned on the mounting block 20.

[0030] In the configuration shown in Figure 3, the holder 21, support portion 22, insulating wall 23, and fixing portion 24 are configured as a single integrated part. In other words, another part (the fourth part) of the mounting block 20 is the fixing portion 24 that positions the electric wire 32 along the mounting block 20.

[0031] Figure 6 is a perspective view of the mounting block 20 and the second case 14. The mounting block 20 has a column portion 25 that can contact a part 142 of the case 12 (second case 14). The column portion 25 restricts the displacement of the part 142 of the second case 14. In the configuration shown in Figure 6, the mounting block 20 has two column portions 25. The column portions 25 have a column shape that protrudes from a part of the mounting block 20 (insulating wall 23).

[0032] As described above, the electrical junction box 10 is placed on top of an external device (not shown). Therefore, external forces may be partially applied to the electrical junction box 10 from the external device. The second case 14 has a seat 143 on its outer surface that can contact the external device. The seat 143 protrudes from the outer surface of the second case 14. The tip surface 251 of the column portion 25 of the mounting block 20 can contact the surface opposite to the seat 143, that is, the inner surface of the second case 14.

[0033] This column portion 25 makes it possible to suppress local deformation of the second case 14 even when the external force acts on it. Thus, in this embodiment, the holder 21, support portion 22, insulating wall 23, fixing portion 24, and column portion 25 of the mounting block 20 are configured as an integrated part. In other words, another part (fifth part) of the mounting block 20 is the column portion 25 that restricts the displacement of a part 142 of the case 12.

[0034] [Second form of electrical junction box 10 and mounting block 20] Figure 7 is an exploded perspective view showing a second form of the electrical junction box 10. With respect to the electrical junction box 10 of the second form shown in Figure 7, the same reference numerals are used for components that have the same function as those of the electrical junction box 10 of the first form shown in Figures 1 to 6. In the second form as well, the electrical junction box 10 has equipment 11 and a case 12 for housing the equipment 11. The case 12 is made of resin.

[0035] Case 12 comprises a first case 13 and a second case 14. Figure 7 shows a simplified representation of the first case 13 and the second case 14. The first case 13 and the second case 14 are joined together by fastening members such as bolts. The equipment 11 is housed between the first case 13 and the second case 14. The electrical connection box 10 has a mounting section 20 for mounting a fuse 33 inside the case 12. The mounting section 20 is included in the equipment 11 housed in the case 12.

[0036] Figure 8 is a perspective view of the mounting section 20 and the busbar 31. The electrical junction box 10 of the second embodiment has a plurality of busbars 31, but Figure 8 shows one of the busbars 31E. The mounting section 20 is made of resin. In this embodiment, the mounting section 20 is a separate component from the first case 13 and the second case 14, and is attached to either the first case 13 or the second case 14. The mounting section 20 is a single block made of resin, and in the second embodiment as well, the mounting section 20 will be referred to and described as the "mounting block 20".

[0037] The mounting block 20 has a holder 21 for holding a fuse 33. The fuse 33 held in the holder 21 is a glass tube fuse. The holder 21 has a box shape that opens towards the first case 13 in order to house the fuse 33. The mounting block 20 has a support portion 22 that is in contact with the bus bar 31E and positions the bus bar 31E. In this embodiment, the mounting block 20 has two support portions 22D and 22E. The first support portion 22D has a columnar shape that protrudes from a part of the bottom wall 211 of the holder 21.

[0038] Figure 9 is a perspective view of the mounting block 20 and the bus bar 31. The two bus bars 31 (31F, 31G) shown in Figure 9 are different from the bus bar 31 (31E) shown by a solid line in Figure 8. The second support portion 22E of the mounting block 20 has a columnar shape that protrudes from another part of the bottom wall 211 of the holder 21. In Figure 8, the bus bar 31F supported by the second support portion 22E is shown by a dashed line. As shown in Figures 8 and 9, the first support portion 22D contacts the plate portion 311 of the plate-shaped bus bar 31E which has a bent portion. The second support portion 22E contacts the plate portion 311 of the plate-shaped bus bar 31F which has a bent portion.

[0039] Each of the busbars 31E and 31F has a heat dissipation function, similar to the busbar 31A of the first configuration shown in Figure 1. Each of the busbars 31E and 31F serves as a heat dissipation component for the equipment 11 of the electrical connection box 10. Each of the busbars 31E and 31F can dissipate heat (via a heat dissipation pad) to an external device (not shown).

[0040] The electrical connection box 10 is positioned on top of the external device such that the busbars 31E and 31F are in contact with a part of the external device via a heat dissipation pad. As a result, the plate portions 311 of the busbars 31E and 31F receive a reaction force from the external device and are pushed toward the holder 21. Therefore, to prevent the plate portions 311 of the busbars 31E and 31F from elastically deforming and moving away due to the reaction force, the first support portion 22D contacts and supports the plate portion 311 of the busbar 31E, and the second support portion 22E contacts and supports the plate portion 311 of the busbar 31F.

[0041] Also in the electrical connection box 10 according to the second embodiment, the holder 21 and the support portion 22 are configured as an integrated component. That is, one part (first part) of the mounting block 20 is the holder 21 that holds the fuse 33, and another part (second part) of the mounting block 20 is the support portion 22 that positions the bus bar 31.

[0042] FIG. 10 is a perspective view showing an exploded state of the set of the mounting block 20 and the bus bars 31 (31F, 31G) shown in FIG. 9. The mounting block 20 has an insulating wall 23. The insulating wall 23 is provided adjacent to and continuously with the holder 21. The insulating wall 23 is positioned adjacent to the target bus bar 31 to be insulated.

[0043] In the case of the embodiment shown in FIGS. 9 and 10, the target bus bars 31 are the two bus bars 31F and 31G that have a large potential difference. The insulating wall 23 is interposed between the bus bar 31F and the bus bar 31G. Electrical insulation between the bus bars 31F and 31G is achieved by the insulating wall 23. As shown in FIGS. 8, 9 and 10, the insulating wall 23 has a slot 27 into which a part 312 of the bus bar 31F is fitted. According to the insulating wall 23, the bus bar 31F is positioned, and insulation between the bus bar 31F and another adjacently disposed bus bar 31G is achieved.

[0044] Also in the electrical connection box 10 according to the second embodiment, the holder 21, the support portion 22 and the insulating wall 23 are configured as an integrated component. That is, a further other part (third part) of the mounting block 20 is the insulating wall 23 positioned adjacent to the target bus bar 31 to be insulated.

[0045] [Regarding each form of the electrical junction box 10] As described above, the electrical junction box 10 of the first form (Figure 1) and the second form (Figure 7) each have a mounting block 20 (mounting portion 20) for mounting a fuse 33 inside the case 12. Part of the mounting block 20 is a holder 21 that holds the fuse 33, and another part of the mounting block 20 is a support portion 22 that can contact the bus bar 31 and positions the bus bar 31. In addition to functioning as a holder 21 for the fuse 33, the mounting block 20 also functions as a support portion 22 for the bus bar 31. The holder 21 and the support portion 22 are configured as an integrated part, which makes it possible to reduce the number of parts in the electrical junction box 10.

[0046] Furthermore, another part of the mounting block 20 is an insulating wall 23 located next to the bus bar 31 to be insulated. In other words, the mounting block 20 also functions as an insulating wall 23. The holder 21, the support part 22, and the insulating wall 23 are configured as a single integrated component, which reduces the number of components in the electrical junction box 10. As shown in Figures 7 to 10, in the second embodiment, the bus bar 31F to be insulated is the bus bar 31 supported by the support part 22 (22E). Note that the bus bar 31 to be insulated may be a bus bar supported by the support part 22, or it may be any other bus bar.

[0047] As shown in Figure 2, in the case of the first form of the electrical junction box 10, another part of the mounting block 20 is a fixing part 24 that positions the electric wire 32 along the mounting block 20. In other words, the mounting block 20 also functions as a fixing part 24 that positions the electric wire 32. The holder 21, the support part 22, the insulating wall 23, and the fixing part 24 are configured as a single integrated component, which makes it possible to reduce the number of parts in the electrical junction box 10.

[0048] Furthermore, as shown in FIG. 6, in the case of the electrical junction box 10 according to the first embodiment, yet another portion of the mounting block 20 is a pillar portion 25 that is capable of contacting a portion 142 of the case 12 and restricts displacement of said portion 142. That is, the mounting block 20 also functions as the pillar portion 25 that restricts displacement of the portion 142 of the case 12. The holder 21, the support portion 22, the insulating wall 23, the fixing portion 24, and the pillar portion 25 are configured as an integrated component, which enables reduction in the number of components of the electrical junction box 10.

[0049] As described above, according to the electrical junction box 10 of each of the first embodiment (FIG. 1) and the second embodiment (FIG. 7), the number of components included in the equipment 11 is reduced. Therefore, the electrical junction box 10 contributes to improved assembly efficiency.

[0050] [Others] In the case of the electrical junction box 10 according to the first embodiment, the mounting block 20 (see FIG. 3) for mounting a fuse 33 includes the holder 21, the support portion 22, the insulating wall 23, the fixing portion 24, and the pillar portion 25, but one or both of the fixing portion 24 and the pillar portion 25 may be omitted, as long as at least the holder 21 and the support portion 22 are provided. In the case of the electrical junction box 10 according to the second embodiment, the mounting block 20 (see FIG. 8) for mounting a fuse 33 includes the holder 21, the support portion 22, and the insulating wall 23, but the insulating wall 23 may be omitted, as long as at least the holder 21 and the support portion 22 are provided.

[0051] Note that, as an invention disclosed for reference, the mounting block 20 (see FIG. 3) for mounting a fuse 33 includes at least two of the holder 21, the support portion 22, the insulating wall 23, the fixing portion 24, and the pillar portion 25. Even in this case, the number of components is reduced, and the electrical junction box 10 contributes to improved assembly efficiency.

[0052] [Others] The above embodiment is illustrative in all respects and is not restrictive. The scope of protection of the present invention is defined by the claims rather than the embodiment, and includes all modifications within the scope equivalent to the configurations recited in the claims.

[0053] 10 Electrical junction box 11 Equipment 12 Case 20 Mounting part 21 Holder 22 Support part 23 Insulating wall 24 Fixing part 25 Column part 31 Bus bar 32 Electric wire 33 Fuse 142 Part of case

Claims

1. An electrical junction box having equipment including a busbar and a fuse, and a case for housing the equipment, wherein the case has a mounting portion for mounting the fuse, a part of the mounting portion is a holder for holding the fuse, and another part of the mounting portion is a support portion that can contact the busbar and position the busbar.

2. The electrical junction box according to claim 1, wherein another part of the mounting portion is an insulating wall located next to the busbar to be insulated.

3. The electrical connection box according to claim 1 or 2, wherein the equipment includes an electric wire, and another part of the mounting portion is a fixing portion for positioning the electric wire along the mounting portion.

4. The electrical junction box according to any one of claims 1 to 3, wherein another part of the mounting portion is a column that can contact a part of the case and restricts the displacement of said part.

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