Branch box, branch structure, and construction method for branch structure

Abstract

To provide a branch box for an automobile power supply trunk circuit, and the like that enable power supply distribution to be performed more easily.SOLUTION: A branch box 1 is used for an automobile power supply trunk circuit. A holder 5 is arranged in an enclosure 3. The holder 5 with a substantially inverted T-shape, has: a trunk cable mounting part 17 on which a trunk cable described later can be mounted; and a bus bar holding part 19 standing upward from the trunk cable mounting part 17. A pair of bus bars 7 are arranged so as to sandwich the bus bar holding part 19 of the holder 5 and are held by the holder 5. The bus bar 7 has a substantially T-shape, and is provided with connector connection parts 21 on both end parts. A trunk cable connection part 23 is provided between the connector connection parts 21 in a manner protruding downward. The connector connection part 21 is connectable to a connector 9, and the trunk cable connection part 23 is connectable to the trunk cable.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a branch box or the like that branches from a main cable connected to a power source to each electrical device or the like in an automobile.

Background Art

[0002] In electric vehicles such as BEV (Battery Electric Vehicle) and HEV (Hybrid Electric Vehicle), a plurality of units driven at high voltage are mounted on the vehicle. Conventionally, a unit including an inverter called a PCU (Power Control Unit) operates an electrical device by supplying power to each unit to be driven.

[0003] However, depending on the output of the PCU and the number of units mounted, a connection box for relay such as a power distribution branch box may be required instead of a direct connection. Therefore, in order to connect a plurality of units, it is necessary to arrange a plurality of power distribution branch boxes.

[0004] As such a structure, for example, a first power line is connected to a power source mounted on a vehicle, the first power line is connected to a first power distributor, and a second power distributor is further connected to the first power distributor via a first main power line. The second power distributor is connected to a third power distributor via a second main power line, and the third power distributor is connected to a fourth power distributor via a third main power line (Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the method of connecting power distributors with a power trunk line, as described in Patent Document 1, a trunk circuit is required to connect each power distributor (distribution junction box) to itself. This results in a problem of increasing the number of components.

[0007] Furthermore, when adding equipment due to minor vehicle changes, it may be necessary to divide the existing main circuit and install new power distribution junction boxes and wire harnesses. However, due to layout constraints, power distribution junction boxes cannot be placed in the shortest possible location between units, resulting in longer connecting wires.

[0008] This invention has been made in view of the above problems, and aims to provide a branch box for a main power supply circuit in an automobile that makes power distribution easier. [Means for solving the problem]

[0009] To achieve the aforementioned objective, the first invention is a branch box for a power main circuit of an automobile, comprising a housing, a holder disposed inside the housing, a busbar held by the holder, and a connector disposed in the housing, wherein the busbar has a main cable connection portion that can be connected to a main cable and a connector connection portion that can be connected to the connector. The holder has a main cable mounting section on which a main cable can be placed, and a busbar holding section that stands above the main cable mounting section and is sandwiched between a pair of busbars, having a thickness that ensures an insulating distance between the busbars, and the busbars are in a substantially T-shape or substantially H-shape. This is a branching box characterized by [this feature].

[0011] A fuse may be connected between the connector connection portion and the connector.

[0012] The aforementioned holder , in a front view, roughly in an inverted T shape or roughly cross shape It can also be made of resin.

[0013] The aforementioned housing may be made of metal.

[0014] The housing may have a cable penetration portion through which a main cable can pass, and a projection may be formed around at least a portion of the cable penetration portion, to which a braided wire can be fixed.

[0015] According to the first invention, since the busbar can be directly connected to the main cable inside the enclosure, there is no need to separate the main cable into multiple branches, and the increase in the number of parts can be minimized. In addition, since a connector is connected to the busbar, it is easy to connect to branched wire harnesses and the like.

[0016] Furthermore, if the holder has a trunk cable mounting section on which a trunk cable can be placed, the trunk cable can be held more securely and displacement can be suppressed. Also, if the holder has a busbar holding section that is sandwiched between a pair of busbars to ensure an insulating distance between the busbars, short circuits between the busbars can be reliably suppressed.

[0017] Furthermore, by placing a fuse between the connector connection and the connector itself, the circuit can be protected from overcurrent.

[0018] Furthermore, if the holder is made of resin, it will be lightweight and, for example, ensure insulation between busbars.

[0019] Furthermore, if the enclosure is made of metal, noise shielding performance can be ensured for the branching box.

[0020] Furthermore, by forming protrusions around at least a portion of the cable penetration area formed in the housing, and by making it possible to fix the braided wire to the protrusions, noise shielding performance by the braided wire can be ensured even for the main cable passing through the housing.

[0021] The second invention is a branching structure using the branching box according to the first invention, wherein at least a pair of main cables penetrate the housing, and inside the housing, a part of the covering of each main cable is removed to expose the internal conductor, and the main cable connection part of the bus bar is joined thereto. This is a branching structure characterized by this.

[0022] The conductor of the main cable and the main cable connection part of the bus bar may be joined by welding.

[0023] The conductor of the main cable and the main cable connection part of the bus bar may be joined by crimping.

[0024] The holder has a main cable placement part on which the main cable can be placed and a bus bar holding part for ensuring the insulation distance between a pair of the bus bars. A pair of the main cables are arranged on the main cable placement part, and the bus bar holding part is arranged between the pair of the main cables, and the bus bar holding part may be sandwiched between the pair of the bus bars. The busbar may be sandwiched between the busbar holder and a pair of main cables.

[0025] According to the second invention, inside the housing, a part of the covering of each main cable is removed to expose the internal conductor, and the main cable connection part of the bus bar and the conductor of the main cable are directly joined. Therefore, there is no need to separate the main cable into a plurality of parts, and an increase in the number of parts can be minimized. Also, for an existing main cable, there is no need to cut the main cable, and the degree of freedom in layout is also high.

[0026] Also, the conductor of the main cable and the main cable connection part of the bus bar may be joined by welding or by crimping. In either case, the conductor of the main cable and the bus bar can be connected with high reliability without using a separate part.

[0027] Also, by arranging a pair of main cables on the main cable placement part of the holder, the main cables can be surely held by the holder. Further, by sandwiching the bus bar holding part arranged between the pair of main cables with the pair of bus bars, the insulation distance between the bus bars can be surely ensured.

[0028] The third invention is a method for constructing a branching structure using the branching box according to the first invention, comprising removing a part of the covering of at least a pair of main cables to expose the internal conductors, joining the main cable connection parts of the bus bars to the conductors of the respective main cables, arranging the holder between the pair of bus bars, The busbar holding portion and the pair of busbars are sandwiched between the pair of main cables. and covering the bus bars and the holder with the housing, which is a method for constructing a branching structure.

[0029] According to the third invention, a branching structure can be easily formed for an existing main cable.

Effect of the Invention

[0030] According to the present invention, it is possible to provide a branching box for an automotive power main circuit or the like that can more easily perform power distribution.

Brief Description of the Drawings

[0031] [Figure 1] Exploded perspective view of the branching box 1. [Figure 2] (a) is a front view of the holder 5, and (b) is a side view of the bus bar 7. [Figure 3] (a) is a partially assembled perspective view of the branching box 1, and (b) is a perspective view showing the branching structure 10. [Figure 4] (a) is an axial cross-sectional view of the branching structure 10, and (b) is a cross-sectional view perpendicular to the axial direction of the branching structure 10. [Figure 5] Axial cross-sectional view of the branching structure 10a. [Figure 6] Exploded perspective view of the branching box 1a. [Figure 7](a) is a front view of holder 5a, and (b) is a side view of busbar 7a. [Figure 8] Axial cross-sectional view of branched structure 10b. [Figure 9] This figure shows the branching structure 10c, where (a) is a perspective view showing the state before the braided wire 35 is attached, and (b) is a perspective view showing the state after the braided wire 35 is attached. [Modes for carrying out the invention]

[0032] Embodiments of the present invention will be described below with reference to the drawings. Figure 1 is an exploded perspective view of the branch box 1. The branch box 1 is used for a power main circuit in an automobile.

[0033] The branch box 1 mainly consists of a housing 3, a holder 5, a pair of busbars 7, and a connector 9. The housing 3 is made of metal, for example. The housing 3 is divided into two parts, which can be joined together and fixed in place. The housing 3 also has a fixing part on its exterior that allows it to be fixed to a car body or the like, and it is possible to connect an earth wire to the fixing part for grounding.

[0034] For each segment of the housing 3, a cable penetration section 25 and a connector fixing section 27 are provided on the opposing surface adjacent to the opening surface (the front surface and the back surface in the figure). The cable penetration section 25 is the part through which the main cable, described later, passes. The cable penetration section 25 is formed in the shape of a notch in each segment of the housing 3, and when the segments are butted together, the overall shape is approximately oval. The direction of the opposing surface in which the cable penetration section 25 is formed is the axial direction of the branch box 1.

[0035] Similarly, a connector fixing portion 27 is formed in the shape of a cutout above the cable penetration portion 25, and when the divided parts are joined together, the overall shape corresponds to the connector 9 (roughly rectangular in the figure). The connector 9 is placed in the connector fixing portion 27 and fixed, for example, with bolts. In other words, the connector 9 is placed in the housing 3. A general-purpose connector can be used as the connector 9.

[0036] A holder 5 is positioned inside the housing 3. Figure 2 is a front view of the holder 5. The holder 5 has a roughly inverted T-shape and includes a trunk cable mounting section 17 on which a trunk cable (described later) can be placed, and a busbar holding section 19 that stands above the trunk cable mounting section 17. The trunk cable mounting section 17 is formed to be roughly flat and is the area where the trunk cable is placed. The trunk cable mounting section 17 may be provided with a fixing structure (such as a band) that can hold and secure the trunk cable.

[0037] The busbar holder 19 has a certain thickness and is positioned between the main cable mounting sections 17 (approximately in the center in the width direction). The busbar holder 19 is sandwiched between a pair of busbars 7, making it possible to ensure an insulating distance between the busbars 7. That is, the holder 5 is made of an insulating material, for example, resin. The busbar holder 19 may be provided with a fixing structure (such as a screw) that can hold and secure the busbars 7.

[0038] A pair of busbars 7 are positioned so as to sandwich the busbar holding portion 19 of the holder 5 and are held by the holder 5. Figure 2(b) is a side view of the busbar 7. The busbar 7 is roughly T-shaped, with connector connection portions 21 at both ends, and a trunk cable connection portion 23 is provided between the connector connection portions 21 so as to protrude downward. The connector connection portions 21 can be connected to a connector 9, and the trunk cable connection portion 23 can be connected to a trunk cable. The busbar 7 is, for example, a plate-shaped metal member.

[0039] Figure 3(a) is a perspective view showing the main cable 11 and busbar 7 etc. fixed to the holder 5, and Figure 3(b) is a perspective view showing the branch structure 10 using the branch box 1 with the housing 3 closed. Figure 4(a) is an axial cross-sectional view of the branch structure 10, and Figure 4(b) is a cross-sectional view perpendicular to the axial direction of the branch structure 10.

[0040] The method for constructing the branch structure 10 involves first arranging at least one pair of main cables 11 (two-pole electric wires, one positive and one negative). The main cable 11 consists of a conductor 13 and a covering portion 15 that insulates the conductor 13. At the location where the branch structure 10 is to be installed, a portion of the covering portion 15 of the main cable 11 is removed to expose the internal conductor 13.

[0041] Next, the main cable connection portion 23 of the busbar 7 is joined to the conductor 13 of each main cable 11. The conductor 13 of the main cable 11 and the main cable connection portion 23 of the busbar 7 may be joined by, for example, welding or by crimping. In the case of crimping, for example, a part of the main cable connection portion 23 may be bent to form the crimped portion. As a result, the main cable 11 and the busbar 7 are electrically connected.

[0042] Next, the holder 5 is positioned so that the busbar holding portion 19 is placed between the pair of busbars 7. That is, the pair of trunk cables 11 are placed on the trunk cable mounting portion 17 of the holder 5, the busbar holding portion 19 is placed between the pair of trunk cables 11, and the busbar holding portion 19 is sandwiched between the pair of busbars 7. If necessary, the trunk cables 11 are fixed to the trunk cable mounting portion 17 and the busbars 7 are fixed to the busbar holding portion 19. Furthermore, connectors 9 are connected to the connector connection portions 21 of each busbar 7. The connectors 9 are fixed by welding or bolts, etc. Note that the holder 5 may be positioned after the connectors 9 are fixed.

[0043] Finally, the branch structure 10 is constructed by butting together and fixing the divided parts of the housing 3 so as to cover the busbar 7 and holder 5, etc. In other words, in the branch structure 10, at least one pair of main cables 11 pass through the housing 3. Also, inside the housing 3, a portion of the covering 15 of each main cable 11 is removed, exposing the internal conductor 13, and the main cable connection portion 23 of the busbar 7 is joined to it. In addition, a connector 9 is connected to the connector connection portion 21 of the busbar 7, and the connector 9 is fixed to the housing 3.

[0044] As described above, according to this embodiment, a portion of the sheathing 15 of the main cable 11 is removed and the busbar 7 is directly joined to the internal conductor 13, so there is no need to cut and connect the main cable 11 at both ends of the branch box 1. In addition, since the busbar 7 and the conductor 13 are joined by welding or crimping, the contact reliability is also high. For example, if you try to make the terminals of a connector etc. directly contact the main cable 11, which has a roughly circular cross-section, with a clip etc., there is a risk of poor contact, but by joining the plate-shaped busbar 7 to the conductor 13 by welding or crimping, the two can be reliably connected.

[0045] Furthermore, since the pair of trunk cables 11 are placed on the trunk cable mounting section 17 of the holder 5, displacement of the trunk cables 11 is suppressed. In addition, the busbar holding section 19 of the holder 5 is provided between the pair of trunk cables 11, and the busbar 7 is fixed to the busbar holding section 19, so that the busbar 7 and the trunk cables 11 are securely fixed to the holder 5, and higher contact reliability can be obtained.

[0046] Furthermore, since the busbar holding portion 19 is made of an insulator and has a thickness sufficient to maintain the insulating distance between the busbars 7, short circuits between the busbars 7 can be suppressed.

[0047] Furthermore, a connector connection portion 21 is formed on the busbar 7, and by joining the connector 9 to the busbar 7, the connector 9 can be integrated with the housing 3. This makes it easy to connect to branch cables and the like that which have general-purpose connectors. In this case, since the connector 9 is arranged on both sides of the housing 3 in the direction in which the main cable 11 passes through, it is also possible to bundle the connected branch cable with the main cable 11. Note that the connector 9 may be on the top side of the housing 3, or it may be arranged on the side perpendicular to the main cable 11.

[0048] Next, a second embodiment will be described. Figure 5 is an axial cross-sectional view showing the branch structure 10a according to the second embodiment. In the following description, components that perform the same functions as those in the first embodiment will be denoted by the same reference numerals as in Figures 1 to 4, and redundant explanations will be omitted.

[0049] The branch structure 10a has a configuration that is substantially the same as the branch structure 10, but differs in that it uses a fuse 29. At least, the fuse 29 is connected between the connector connection portion 21 of the busbar 7 that is joined to the positive terminal main cable 11 and the connector 9.

[0050] In the illustrated example, fuses 29 are placed at both connector connection points 21, but they may be placed at only one. Furthermore, the fuse 29 may be a tube fuse or a plug-in type like a blade fuse. In this case, a plug-in hole may be formed in the corresponding part of the housing 3, and the fuse may be inserted from the outside to connect the busbar 7 and the connector 9 via the fuse.

[0051] According to the second embodiment, the same effects as the first embodiment can be obtained. Furthermore, by using the fuse 29, the in-vehicle unit and the like can be protected from overcurrent.

[0052] Next, a third embodiment will be described. Figure 6 is an exploded perspective view of the branch box 1a. The branch box 1a has a configuration that is substantially the same as the branch box 1, but differs in that it uses a holder 5a and a bus bar 7a.

[0053] Figure 7(a) is a front view of holder 5a. In holder 5a, the busbar holding portion 19 protrudes below the trunk cable mounting portion 17 relative to holder 5. That is, in a front view, holder 5a has a roughly cross shape. The busbar holding portion 19 is longer on the upper side than on the lower side of the trunk cable mounting portion 17 by the diameter of the trunk cable 11.

[0054] Furthermore, the trunk cable mounting section 17 is not continuous with the holder 5a in the depth direction (axial direction), and a notch 18 is formed in part of it. That is, the trunk cable mounting section 17 is not formed in the notch 18, and the busbar holding section 19 is exposed between the trunk cable mounting sections 17.

[0055] Figure 7(b) is a side view of the busbar 7a. The busbar 7a has connector connection parts 21 formed on both the upper and lower sides of the trunk cable connection part 23 relative to the busbar 7. In other words, the busbar 7a has a roughly H-shape.

[0056] Figure 8 is an axial cross-sectional view showing the branching structure 10b using the branching box 1a. The main cable connection portion 23 of the busbar 7a is positioned in the notch 18 of the holder 5a. The connector connection portion 21 of the busbar 7a is held by the busbar holding portions 19 above and below the main cable mounting portion 17 of the holder 5a.

[0057] A connector 9 is connected to each connector connection point 21 of the busbar 7a. In other words, a total of four connectors 9 are arranged above and below the main cable 11, facing each other in the axial direction.

[0058] According to the third invention, the same effects as the first invention can be obtained. Furthermore, by arranging connectors 9 on both the upper and lower sides of the main cable 11, even if the number of connectors 9 is increased, sufficient spacing between the connectors 9 can be ensured, improving connection workability and suppressing short circuits, etc.

[0059] Next, a fourth embodiment will be described. Figure 9 shows the branch structure 10c according to the fourth embodiment, where Figure 9(a) shows the state before attaching the braided wire, and Figure 9(a) shows the state after attaching the braided wire 35.

[0060] In the branching structure 10c, projections 31 are formed on at least a portion of the periphery of the cable penetration portion 25 of the housing 3, projecting outward in the axial direction. The projections 31 may be formed around the entire circumference of the outer periphery of the cable penetration portion 25, but for example, as shown in the figure, they are formed on opposing arcs of the oval-shaped cable penetration portion 25. The braided wire 35 can be fixed to the housing 3 by covering the projections 31 with the braided wire 35 and placing the band 33 around the outer circumference of the braided wire 35. The joining of the braided wire 35 and the projections 31 is not limited to the band 33, but may also be done by welding or brazing.

[0061] As mentioned above, since the housing 3 is made of metal, it can ensure a shielding function for the branch box. On the other hand, the main cable 11 is usually inserted into a braided wire or shielded conduit to ensure shielding. In this case, the braided wire 35 can be easily fixed to the projection 31 and the braided wire 35 and the housing 3 can be electrically connected, so there is no need to ground the braided wire 35 by a separate means such as an earth wire.

[0062] According to the fourth embodiment, the same effects as the first embodiment can be obtained. Furthermore, since the braided wire 35 can be easily fixed to the housing 3, the shielding of the entire circuit, including the branch box, can be easily ensured.

[0063] Although embodiments of the present invention have been described above with reference to the attached drawings, the technical scope of the present invention is not limited to the embodiments described above. It is clear to those skilled in the art that various modifications or alterations can be conceived within the scope of the technical idea described in the claims, and these will naturally also fall within the technical scope of the present invention.

[0064] For example, it goes without saying that each embodiment can be combined with others. [Explanation of Symbols]

[0065] 1, 1a... Branch box 3…cabinet 5, 5a... Holder 7, 7a... Bus bar 9... Connector 10, 10a, 10b, 10c... Branch structure 11… Main cable 13... Conductor 15... Covering part 17... Main cable mounting section 18... Notch 19...Bus bar holder 21…Connector connection part 23... Main cable connection section 25………Cable penetration point 27…Connector fixing part 29…Fuse 31……protrusion 33...band 35……braided wire

Claims

1. A branch box for the main power supply circuit of an automobile, The casing and A holder positioned inside the aforementioned housing, A bus bar held by the holder, The connectors arranged in the aforementioned housing, It is equipped with, The busbar has a trunk cable connection portion that can be connected to a trunk cable and a connector connection portion that can be connected to the connector, The holder has a trunk cable mounting section on which a trunk cable can be placed, and a busbar holding section that stands above the trunk cable mounting section and is sandwiched between a pair of busbars, having a thickness that ensures an insulating distance between the busbars. The aforementioned busbar is characterized by being roughly T-shaped or roughly H-shaped in shape.

2. The branch box according to claim 1, characterized in that a fuse is connected between the connector connection portion and the connector.

3. The branch box according to claim 1 or 2, characterized in that the holder is made of resin and is substantially in the shape of an inverted T or a cross when viewed from the front.

4. The branch box according to any one of claims 1 to 3, characterized in that the housing is made of metal.

5. The housing has a cable penetration section through which a main cable can pass. The branch box according to any one of claims 1 to 4, characterized in that a projection is formed on at least a part of the periphery of the cable penetration portion, and a braided wire can be fixed to the projection.

6. A branching structure using a branching box according to any one of claims 1 to 5, At least one pair of trunk cables pass through the aforementioned enclosure, A branching structure characterized in that, inside the housing, a portion of the covering of each of the main cables is removed, exposing the internal conductors, and the main cable connection portion of the busbar is joined.

7. The branch structure according to claim 6, characterized in that the conductor of the main cable and the main cable connection portion of the busbar are joined by welding.

8. The branching structure according to claim 6, characterized in that the conductor of the main cable and the main cable connection portion of the busbar are joined by crimping.

9. The holder has a trunk cable mounting section on which a trunk cable can be placed, and a bus bar holding section that ensures an insulating distance between a pair of bus bars. The branching structure according to any one of claims 6 to 8, characterized in that a pair of trunk cables are arranged on the trunk cable mounting section, the busbar holding section is arranged between the pair of trunk cables, and the busbar holding section is sandwiched between the pair of busbars.

10. The branching structure according to claim 9, characterized in that the busbar holding portion and the pair of busbars are sandwiched between the pair of main cables.

11. A method for constructing a branch structure using a branch box according to any one of claims 1 to 5, Remove a portion of the sheathing from at least one pair of trunk cables to expose the internal conductors. The main cable connection portion of the busbar is joined to the conductor of each of the main cables. A method for constructing a branch structure, characterized by arranging the holder between a pair of busbars, sandwiching the busbar holding portion and the pair of busbars with a pair of main cables, and covering the busbars and the holder with the housing.

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