阅读说明：本技术 电接线箱 (Electrical connection box ) 是由 藤村勇贵 竹田仁司 于 2020-04-28 设计创作，主要内容包括：本公开中的电接线箱是具备壳体、电源电路及分支电路的电接线箱(10),分支电路被设为具有能够装卸的过电流切断元件并且从电源电路分支的电路,壳体具有壳体主体、相对于壳体主体能够装卸的罩(23)及罩用密封部件(24),壳体主体具有第一作业孔(44),并且收容电源电路及分支电路,第一作业孔(44)在使过电流切断元件面向外侧的位置形成为比壳体主体的顶板(41)的外形尺寸小的外形尺寸,罩(23)以封闭第一作业孔(44)的方式装配于壳体主体,罩用密封部件(24)紧贴于壳体主体中的第一作业孔(44)的周缘部和罩(23)。(The electric connection box (10) comprises a housing, a power supply circuit, and a branch circuit, wherein the branch circuit is provided with a detachable overcurrent cutoff element and is a circuit branched from the power supply circuit, the housing comprises a housing main body, a cover (23) detachable relative to the housing main body, and a sealing member (24) for the cover, the housing main body is provided with a first operation hole (44) and accommodates the power supply circuit and the branch circuit, the first operation hole (44) is formed to be smaller in external dimension than the external dimension of a top plate (41) of the housing main body at the position where the overcurrent cutoff element faces the outer side, the cover (23) is assembled on the housing main body in a mode of closing the first operation hole (44), and the sealing member (24) for the cover is tightly attached to the peripheral edge of the first operation hole (44) in the housing main body and the cover (23).)

1. An electrical connection box comprises a housing, a power circuit and a branch circuit,

the branch circuit is provided as a circuit having a detachable overcurrent cutoff element and branching off from the power supply circuit,

the case has a case body, a cover attachable to and detachable from the case body, and a cover sealing member having elasticity,

the housing main body has a first working hole and houses the power supply circuit and the branch circuit,

the first working hole is formed to have an outer dimension smaller than an outer dimension of the top plate so as to penetrate the top plate of the case body at a position where the overcurrent cutoff element faces outward,

the cover is attached to the housing main body so as to close the first working hole, and the cover sealing member is in close contact with the peripheral edge portion of the first working hole in the housing main body and the cover.

2. The electrical junction box of claim 1,

the casing body comprises a lower casing, an upper casing and a sealing component for the elastic casing,

the lower case and the upper case are assembled with each other,

the sealing member for housing is closely attached to the lower housing and the upper housing to seal the lower housing and the upper housing in a water-tight state,

the branch circuit has a lower branch circuit disposed in the lower case and an upper branch circuit disposed in the upper case,

the lower case has at least one connector connected to the lower side branch circuit,

the upper case has at least one connector connected to the upper side branch circuit,

the lower branch circuit and the upper branch circuit are arranged in a direction in which the lower case and the upper case are assembled with each other.

3. The electrical junction box of claim 2,

the power circuit is configured in the lower shell,

the upper side branch circuit has a branch bus bar connected to the power supply circuit.

4. The electrical junction box of claim 3,

the upper case has an upper base on which the overcurrent cutoff element of the upper branch circuit is disposed,

the lower case has a lower base on which the overcurrent cutoff element of the lower branch circuit is disposed,

the upper base and the lower base are arranged in a direction in which the lower case and the upper case are assembled with each other.

5. The electrical junction box of claim 4,

the upper case has a pedestal receiving portion to which the upper pedestal is detachably attached,

the pedestal receiving portion has a second working hole closed by the upper pedestal.

6. The electrical junction box of claim 5,

the branch bus bar can be connected to the power supply circuit through the first work hole and the second work hole.

Technical Field

The present disclosure relates to an electrical junction box.

Background

An electrical junction box for an automobile is disclosed in japanese patent application laid-open No. 2019-47535, for example.

The electric junction box has an upper case and a lower case assembled up and down. A laminated bus bar connected to a power circuit, a relay bus bar connected to the laminated bus bar, a distribution board, a fuse, and the like are provided on an upper portion of the lower case. The distribution board is connected to the relay bus bar via a fuse, and constitutes a branch circuit branching from the power supply circuit.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2019-47535

Disclosure of Invention

Problems to be solved by the invention

However, the electrical junction box is configured such that the fuse is replaced by removing the upper housing from the lower housing and exposing the entire upper portion of the lower housing.

However, when the fuse is replaced by exposing the entire upper portion of the lower case, the area for waterproofing between the lower case and the upper case becomes large, and therefore the possibility of water entering between the lower case and the upper case becomes high. As a result, the waterproofness of the electrical junction box is reduced.

In the present specification, a technique for improving the replacement workability and improving the water resistance is disclosed.

Means for solving the problems

An electrical junction box of the present disclosure is an electrical junction box including a housing, a power supply circuit, and a branch circuit provided as a circuit having a detachable overcurrent cutoff element and branching off from the power supply circuit, the case has a case body, a cover attachable to and detachable from the case body, and an elastic cover seal member, the case body has a first working hole, and the power supply circuit and the branch circuit are housed, the first working hole is formed to have an outer dimension smaller than an outer dimension of the top plate so as to penetrate the top plate of the case body at a position where the overcurrent cutoff element faces outward, the cover is attached to the housing main body so as to close the first working hole, and the cover sealing member is in close contact with the peripheral edge portion of the first working hole in the housing main body and the cover.

Effects of the invention

According to the present disclosure, the replacement workability can be improved, and the waterproofness can be improved.

Drawings

Fig. 1 is an exploded perspective view of an electrical junction box according to an embodiment.

Fig. 2 is a perspective view of the electrical junction box.

Fig. 3 is a plan view of the electrical junction box.

Fig. 4 is a rear view of the electrical junction box.

Fig. 5 is a perspective view showing a state before the upper case is assembled to the lower case.

Fig. 6 is a plan view of the lower case in a state where the power supply circuit and the lower branch circuit are housed.

Fig. 7 is a bottom view of the upper case showing a state in which the upper branch circuit is accommodated.

Fig. 8 is a perspective sectional view taken along line a-a of fig. 3.

Fig. 9 is a sectional view taken along line a-a of fig. 3.

Fig. 10 is a sectional view taken along line B-B of fig. 3.

Fig. 11 is a perspective view of the electrical junction box with the cover removed.

Fig. 12 is a plan view of the electrical junction box with the cover removed.

Fig. 13 is a perspective view of the electrical junction box with the cover and the upper base removed.

Fig. 14 is a plan view of the electrical junction box with the cover and the upper base removed.

Detailed Description

[ description of embodiments of the present disclosure ]

First, embodiments of the present disclosure are described.

(1) An electrical junction box includes a housing, a power supply circuit, and a branch circuit provided as a circuit having a detachable overcurrent cutoff element and branching from the power supply circuit, the case has a case body, a cover attachable to and detachable from the case body, and an elastic cover seal member, the case body has a first working hole, and the power supply circuit and the branch circuit are housed, the first working hole is formed to have an outer dimension smaller than an outer dimension of the top plate so as to penetrate the top plate of the case body at a position where the overcurrent cutoff element faces outward, the cover is attached to the housing main body so as to close the first working hole, and the cover sealing member is in close contact with the peripheral edge portion of the first working hole in the housing main body and the cover.

Since the overcurrent cutoff element is in a state of facing outward from the first working hole by detaching the cover from the case main body, the overcurrent cutoff element can be easily replaced through the first working hole. This makes it possible to improve the workability of replacing the overcurrent cutoff element. The first working hole is formed to have an outer dimension smaller than an outer dimension of the top plate of the case main body, and when the cover is attached to the case main body, the first working hole is closed to a water-tight state by the cover and the cover sealing member. Thus, for example, the waterproof property of the electric connection box can be improved as compared with a case where the housing is largely opened and the waterproof region is enlarged.

(2) The case body includes a lower case, an upper case, and an elastic sealing member for the case, the lower case and the upper case are assembled with each other, the sealing member for the case is tightly attached to the lower case and the upper case to seal a space between the lower case and the upper case in a watertight state, the branch circuit includes a lower branch circuit disposed in the lower case and an upper branch circuit disposed in the upper case, the lower case includes at least one connector connected to the lower branch circuit, the upper case includes at least one connector connected to the upper branch circuit, and the lower branch circuit and the upper branch circuit are arranged in a direction in which the lower case and the upper case are assembled with each other.

For example, when connectors connected to the branch circuits are provided in the lower case and the upper case, respectively, the following methods are conceivable: most of the branch circuit is disposed in the lower case, and the branch circuit disposed in the lower case is connected to the connector disposed in the upper case by a wire. However, according to such a method, the upper case needs to be provided only for providing the connector, which leads to an increase in size of the electrical junction box. In addition, although the electric junction box is large, a dead space is generated in the upper case.

However, according to such a configuration, the lower branch circuit connected to the connector of the lower case is disposed in the lower case, and the upper branch circuit connected to the connector of the upper case is disposed in the upper case. That is, by effectively using the waterproof case main body, the case main body can be downsized, and the electric junction box can be downsized.

(3) The power circuit is disposed in the lower case, and the upper side branch circuit has a branch bus bar connected to the power circuit.

For example, when assembling the lower case and the upper case, the electrical junction box that connects the electric wires of the upper branch circuit to the power supply circuit disposed in the lower case needs to secure an extra length housing area for housing the extra length of the electric wires in the case. Therefore, the housing is increased in size according to the amount of the extra-long storage area.

However, since the upper branch circuit has the branch bus bar connected to the power supply circuit, it is not necessary to secure an extra-long housing area in the housing when assembling the lower housing and the upper housing, and the housing can be downsized. This enables the electric connection box to be further downsized.

(4) The upper case has an upper base on which the overcurrent cutoff element of the upper side branch circuit is disposed, the lower case has a lower base on which the overcurrent cutoff element of the lower side branch circuit is disposed, and the upper base and the lower base are arranged in a direction in which the lower case and the upper case are assembled with each other.

As compared with the case where the upper base and the lower base are arranged offset in the direction intersecting the assembling direction of the lower housing and the upper housing, it is possible to prevent the electrical junction box from becoming large in the intersecting direction.

(5) The upper case has a pedestal receiving portion to which the upper pedestal is detachably attached, and the pedestal receiving portion has a second working hole closed by the upper pedestal.

By detaching the upper base from the base receiving portion, the lower base can be made to face outward through the first working hole and the second working hole. That is, the overcurrent cutoff element disposed on the lower base can be replaced by the first working hole and the second working hole. Thus, for example, compared to a case where the entire circuit including the power supply circuit is exposed to replace the overcurrent cutoff element, the replacement operation of the overcurrent cutoff element can be performed favorably while improving the water resistance.

(6) The branch bus bar can be connected to the power supply circuit through the first work hole and the second work hole.

For example, when the bus bar of the upper branch circuit is connected to the power supply circuit when the lower case and the upper case are assembled, the connection between the bus bar and the power supply circuit cannot be visually confirmed by the case, and the workability of connection between the upper branch circuit and the power supply circuit is lowered.

However, in the present embodiment, since the branch bus bar is detachably attached to the power supply circuit through the first work hole and the second work hole, for example, when the lower case and the upper case are assembled, the workability of connecting the power supply circuit and the upper branch circuit is superior to that when the bus bar of the upper branch circuit is connected to the power supply circuit.

[ details of embodiments of the present disclosure ]

Specific examples of the electric junction box of the present disclosure will be described with reference to the following drawings. The present disclosure is not limited to these examples, but is defined by the claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

< embodiment >

One embodiment of the present disclosure will be described with reference to fig. 1 to 14.

The present embodiment exemplifies an electrical junction box mounted in a battery pack mounted on a vehicle, not shown. In the following description, the direction indicated by the arrow Z is referred to as up, the direction indicated by the arrow Y is referred to as down, and the direction indicated by the arrow X is referred to as right. In addition, in some cases, only one of the plurality of identical components is denoted by a reference numeral, and the other components are not denoted by the reference numeral.

[ Electrical connection box 10]

As shown in fig. 1 and 2, the electrical junction box 10 includes a housing 20, a pair of power supply bus bars 61, a plurality of branch bus bars 71, a plurality of fuses (an example of an "overcurrent cutoff element") F, and a plurality of wire harnesses 90.

[ case 20]

The case 20 is made of insulating synthetic resin. As shown in fig. 1 to 4, the case 20 includes a case main body 21, a cover 23, and a cover sealing member 24.

[ case body 21]

The housing main body 21 is formed in a flat box shape that is long in the front-rear direction. The case main body 21 includes a lower case 30, an upper case 40, and a case sealing member 25.

[ lower case 30]

As shown in fig. 1, 5, and 6, the lower case 30 is formed in a tray shape that is long in the front-rear direction and opens upward. The lower case 30 is assembled with an upper case 40 described later from above to constitute a case main body 21. The lower case 30 includes a bottom plate 31, four lower side plates 32, and a lower flange 33.

The bottom plate 31 is formed in a rectangular shape that is long in the front-rear direction. A lower base 34 having a rectangular shape in plan view is fixed to the center of the bottom plate 31 by a bolt BT.

Lower pedestal 34 is formed in a convex shape protruding upward. As shown in fig. 6, a positive electrode branch bus bar 72 and a first negative electrode branch bus bar 73, which will be described later, among the plurality of branch bus bars 71, a pair of first relay bus bars 35, and two fuses F are placed on the lower base 34. The pair of first relay bus bars 35 are arranged and fixed in the front-rear direction in a state of extending in the front-rear direction at the left end portion of the lower base 34. The left end of each first relay bus bar 35 is connected to the wire harness 90, and the right end is connected to the fuse F.

The four lower side plates 32 are formed to extend upward from the outer edge of the bottom plate 31.

The side edges of the adjacent lower side plates 32 are connected to each other. Thus, the lower case 30 is formed into a tray type, and a power supply circuit 60 and a branch circuit 70, which will be described later, are housed in the lower case 30 from above.

A pair of front cable introduction ports 32A are formed in the front lower plate 32 of the four lower plates 32 so as to penetrate the lower plate 32 in the front-rear direction. The front cable introduction port 32A is introduced with a power cable, not shown, in a water-sealed state.

A pair of connector attachment openings 32B are formed in the lower side plate 32 on the rear side of the four lower side plates 32 so as to penetrate the lower side plate 32. Two harnesses 90 of the plurality of harnesses 90 are mounted in a water-tight state in the pair of connector mounting ports 32B.

The lower flange portion 33 is provided around the upper end edges of the four lower side plates 32. The lower flange portion 33 is formed in a rectangular shape at the upper end edges of the four lower side plates 32 so as to extend outward from the respective lower side plates 32. A rectangular seal groove 36 is formed in an upper surface of the lower flange portion 33 so as to be recessed along the lower flange portion 33. In the seal groove 36, a seal member 25 for a housing having elasticity is fitted from above.

[ case seal member 25]

The housing sealing member 25 is formed in a rectangular ring shape by an elastic member such as rubber. The case seal member 25 is fitted to the seal groove 36 in a state where an upper end portion protrudes upward from the seal groove 36. When the upper case 40 is assembled to the lower case 30 from above, the case seal member 25 is in close contact with the lower flange portion 33 of the lower case 30 and an upper flange portion 43 of the upper case 40, which will be described later, over the entire circumference. That is, the case sealing member 25 seals the space between the lower case 30 and the upper case 40 in a water-tight state so as not to allow water or the like to enter between the lower case 30 and the upper case 40.

[ Upper case 40]

As shown in fig. 1, 5, and 7 to 10, the upper case 40 is formed in a tray shape that is long in the front-rear direction and opens downward. The upper case 40 includes a top plate 41, four upper side plates 42, and an upper flange 43.

The top plate 41 is formed in a rectangular shape long in the front-rear direction. The top plate 41 has a rectangular first work hole 44 in a plan view. The first work hole 44 is formed in the center portion of the top plate 41 in the left-right direction and in the center portion of the top plate 41 in the front-rear direction. The first work hole 44 is formed such that the width dimension in the left-right direction is smaller than the width dimension of the top plate 41, and the longitudinal dimension in the front-rear direction is smaller than the longitudinal dimension of the top plate 41. That is, the first working hole 44 is formed in the upper case 40 to have an outer dimension smaller than that of the top plate 41.

As shown in fig. 8 to 10, a rectangular seal attachment rib 44A is formed on the upper surface of the top plate 41 so as to protrude along the outer peripheral edge of the first work hole 44. A cover seal member 24 described later is fitted to the seal fitting rib 44A along the outer peripheral surface.

As shown in fig. 8 to 12, the upper case 40 has a base receiving portion 45 attached to the inner side (lower surface) of the top plate 41.

The pedestal receiving portion 45 is formed to protrude downward from the lower surface of the top plate 41 in a concave shape. The base receiving portion 45 has a mounting flange 47 extending along the top plate 41. The mounting flange 47 is fixed to the top plate 41 from below by bolts BT, and the base receiving portion 45 is fixed to the lower surface of the top plate 41.

The pedestal receiving portion 45 has a rectangular bottom portion 48 slightly smaller than the first working hole 44. Therefore, as shown in fig. 11 and 12, the bottom portion 48 faces upward through the first working hole 44.

As shown in fig. 10, 13, and 14, a second working hole 49 is formed in the rectangular bottom portion 48 of the base receiving portion 45. The second work hole 49 is formed in a rectangular shape so as to penetrate the bottom portion 48 in the vertical direction. The second work hole 49 is disposed above the lower base 34 of the lower case 30, and is vertically aligned with the first work hole 44.

That is, as shown in fig. 9, 10, and 14, the first work hole 44 and the second work hole 49 are arranged in the vertical direction in a region where the power supply circuit 60 is not exposed upward and at a position where the lower base 34 of the lower case 30 faces upward.

An upper base 50 is detachably mounted on a bottom portion 48 of the base receiving portion 45 from above. Therefore, in a state where the upper base 50 is mounted on the base receiving portion 45, as shown in fig. 11 and 12, the first working hole 44 faces the upper base 50 upward.

As shown in fig. 1 and 13, the upper base 50 is formed in a rectangular shape in plan view slightly larger than the second working hole 49 of the base receiving portion 45 in the front-rear-left-right direction. The upper base 50 includes a rectangular component mounting portion 51 in a plan view and a fixing portion 53 provided on the outer periphery of the component mounting portion 51.

As shown in fig. 8 to 11, the component mounting portion 51 is formed one step higher than the fixing portion 53. The second negative branch bus bar 75 of the plurality of branch bus bars 71, the pair of second relay bus bars 52, and the two fuses F can be mounted on the component mounting portion 51. That is, as shown in fig. 11 and 12, the first working hole 44 faces the upper base 50 on which the two fuses F are mounted upward.

As shown in fig. 5, 9, 10, and 13, the pair of second relay bus bars 52 is fixed to the component mounting portion 51 so as to penetrate the component mounting portion 51 in the vertical direction at the right end portion of the component mounting portion 51. A portion of the second relay bus bar 52 disposed on the component mounting portion 51 is connected to the fuse F mounted on the component mounting portion 51. On the other hand, a wire harness 90 is connected to a lower end portion of the second relay bus bar 52 extending downward from the component mounting portion 51.

The fixing portion 53 is formed to be continuous with the outer periphery of the component mounting portion 51 by one step lower than the component mounting portion 51. As shown in fig. 8 to 10, when the upper base 50 is mounted on the base receiving portion 45, the fixing portion 53 is disposed on the outer peripheral edge portion of the second working hole 49 of the bottom portion 48. The upper base 50 is fixed to the base receiving portion 45 by fixing the fixing portion 53 to the bottom portion 48 from above with four bolts BT. Further, by removing the four bolts BT, the upper base 50 can be removed from the base receiving portion 45 as shown in fig. 13.

That is, the upper base 50 can be attached to and detached from the base receiving portion 45 through the first working hole 44.

The four upper side plates 42 are formed to extend downward from the outer edge of the top plate 41.

The side edges of the adjacent upper side plates 42 are connected to each other. As a result, as shown in fig. 5 and 7 to 10, the upper case 40 is configured to be a tray type, and a branch circuit 70 described later is housed from below in the upper case 40.

As shown in fig. 5 and 7, a pair of rear cable introduction ports 42A and a pair of connector attachment ports 42B are formed in the rear upper side plate 42 of the four upper side plates 42 so as to penetrate the upper side plate 42 in the front-rear direction.

Power cables, not shown, connected to a pair of power bus bars 61, which will be described later, are respectively introduced into the pair of rear cable introduction ports 42A in a water-sealed state.

Two harnesses 90 of the plurality of harnesses 90 are mounted in a water-tight state in the pair of connector mounting ports 42B.

The upper flange 43 is provided around the lower edges of the four upper side plates 42. The upper flange 43 is formed in a rectangular shape at the upper end edge of the lower case 30 so as to extend outward from each upper side plate 42. As shown in fig. 3, the upper flange 43 is fixed to the lower flange 33 by six bolts BT arranged in line on the longer side portion. Thereby, the upper case 40 is fixed to the lower case 30.

The lower surface of the upper flange 43 is a flat seal surface 43A. When the upper case 40 is fixed to the lower case 30, the sealing surface 43A sandwiches the case seal member 25 from the top-bottom direction together with the bottom surface of the seal groove 36, as shown in fig. 8 to 10. That is, the case seal member 25 is closely attached to the seal surface 43A and the bottom surface of the seal groove 36 over the entire circumference, and the lower flange portion 33 and the upper flange portion 43 are sealed. That is, the upper case 40, the lower case 30, and the case sealing member 25 are integrated to constitute the case main body 21 in which the upper case 40 and the lower case 30 are sealed.

[ sealing Member 24 for cover ]

The cover seal member 24 is formed in a rectangular ring shape by an elastic member such as rubber. The cover seal member 24 is configured to be larger than the seal attachment rib 44A in the vertical direction. Therefore, when the cover sealing member 24 is fitted to the outer periphery of the seal fitting rib 44A, the cover sealing member 24 projects further upward than the seal fitting rib 44A.

[ cover 23]

As shown in fig. 1 to 4, the cover 23 is formed in a rectangular plate shape larger than the first working hole 44 of the housing main body 21 in the front-rear-left-right direction. Cover 23 is fixed to upper case 40 by fixing four corners of cover 23 to top plate 41 with bolts.

As shown in fig. 8 to 10, a cover-side sealing surface 23A that contacts the cover seal member 24 from above is formed over the entire periphery of the outer peripheral edge portion of the cover 23. By fixing the cover 23 to the upper case 40, the cover-side sealing surface 23A sandwiches the cover seal member 24 together with the top plate 41 from the up-down direction. Thereby, the cover sealing member 24 is brought into close contact with the cover 23 and the top plate 41, and the first working hole 44 is sealed in a watertight state by the cover 23 and the cover sealing member 24.

[ Power bus bar 61]

Each of the pair of power bus bars 61 is formed by processing a conductive metal plate material. As shown in fig. 5 and 6, most of the pair of power bus bars 61 are housed in the lower case 30. One of the pair of power supply bus bars 61 is a negative electrode bus bar 61N, and the other is a positive electrode bus bar 61P. In the present embodiment, the power bus bar 61 disposed rearward of the left front cable introduction port 32A of the pair of power bus bars 61 is set as a positive bus bar 61P, and the power bus bar 61 disposed rearward of the right front cable introduction port 32A is set as a negative bus bar 61N. Power cables corresponding to the respective polarities are connected to the ends of the power bus bars 61. That is, the power supply circuit 60 is configured by flowing a large current through the pair of power supply bus bars 61.

As shown in fig. 6, the positive electrode bus bar 61P includes a first positive electrode portion 62, a second positive electrode portion 63, and a third positive electrode portion 64. The first positive electrode portion 62 extends rearward from a position rearward of the left front cable introduction port 32A along the left lower side plate 32. The second positive electrode portion 63 extends rightward between the lower base 34 and the lower plate 32 on the rear side from the rear end portion of the first positive electrode portion 62 to the right side portion of the lower housing 30. The third positive electrode portion 64 extends in a crank shape from the right end of the second positive electrode portion 63 to the rear cable introduction port 42A on the left side of the upper case 40. The positive electrode bus bar 61P is fixed to the lower case 30 by fixing the front end portion of the first positive electrode portion 62 and the right end portion of the second positive electrode portion 63 to the bolt fixing portion 37 of the lower case 30 by bolts.

The negative electrode bus bar 61N includes a first negative electrode portion 65, a second negative electrode portion 66, and a third negative electrode portion 67.

First negative electrode portion 65 extends rearward to the front of lower base 34 so as to be one step higher from the position rearward of right front cable introduction port 32A. Second negative electrode portion 66 extends rightward from a position slightly to the right of first negative electrode portion 65 to the right of lower case 30 so as to be continuous with the rear end portion of first negative electrode portion 65. Third negative electrode portion 67 extends straight from the right end of second negative electrode portion 66 to the right rear end of lower case 30. The rear end of the third negative electrode portion 67 extends in a crank shape to the rear cable introduction port 42A on the right side of the upper case 40. The negative electrode bus bar 61N is fixed to the lower case 30 by bolting the left end portion and the center portion in the left-right direction of the second negative electrode portion 66 to the bolt fixing portion 37 of the lower case 30.

[ Branch bus bar 71]

Each of the plurality of branch bus bars 71 is formed by processing a conductive metal plate material having a thickness smaller than that of the power supply bus bar 61.

As shown in fig. 1 and 5, the plurality of branched bus bars 71 includes three branched bus bars 71 in total, i.e., a positive branched bus bar 72, a first negative branched bus bar 73, and a second negative branched bus bar 75.

As shown in fig. 6 and 10, the positive electrode branch bus bar 72 is bolt-fixed to the bolt fixing portion 37 of the lower case 30 together with the right side end portion of the second positive electrode portion 63 of the positive electrode bus bar 61P. Thereby, the positive electrode branch bus bar 72 is electrically connected to the positive electrode bus bar 61P.

The positive branch bus bar 72 extends in a crank shape from the position of the right end of the second positive electrode portion 63 to the same height position as the upper surface of the lower base 34, and then extends leftward on the rear side of the lower base 34.

Four harnesses 90, which will be described later, are connected in a row in the left-right direction to a portion of the positive electrode branching bus bar 72 disposed on the lower base 34.

As shown in fig. 5, 6, and 8, the first negative electrode branch bus bar 73 is bolted to the bolt fixing portion 37 of the lower case 30 together with the center portion in the left-right direction of the second negative electrode portion 66 of the negative electrode bus bar 61N. Thereby, the first negative electrode branch bus bar 73 is electrically connected to the negative electrode bus bar 61N. First negative branch bus bar 73 extends in a crank shape from the position of the center portion of second negative electrode portion 66 in the left-right direction to the upper surface of lower base 34, and then extends in the front-rear direction on the right side portion of lower base 34. Two fuses F described later are connected in a front-rear direction in a portion of the first negative branch bus bar 73 disposed on the lower base 34.

As shown in fig. 8 and 9, the second negative branch bus bar 75 is bolted to the bolt fixing portion 37 of the lower case 30 together with the left end portion of the second negative electrode portion 66. Thereby, the second negative electrode branch bus bar 75 is electrically connected to the negative electrode bus bar 61N. Second negative branch bus bar 75 extends in a crank shape from the position of the left end of second negative electrode portion 66 to component mounting portion 51 of upper base 50 of upper case 40, and then extends in the front-rear direction on the left side portion of component mounting portion 51. That is, as shown in fig. 8 and 9, second negative branch bus bar 75 extends in the vertical direction (the direction in which lower case 30 and upper case 40 are assembled to each other) and is connected to power supply circuit 60. Two fuses F described later are connected in a front-rear direction in a portion of the second negative branch bus bar 75 disposed on the component mounting portion 51.

[ fuse F ]

As shown in fig. 5, 6, 8, and 9, the fuse F is incorporated in the branch circuit 70, and is a general fuse that cuts off a current when the current is equal to or greater than a predetermined value.

As shown in fig. 9, each of the plurality of fuses F has a cylindrical body portion F1 and a pair of terminal portions F2 provided at both ends of the body portion F1. A fuse portion, not shown, is provided in the body portion F1. When an overcurrent flows through the fuse portion, the main body portion F1 fuses and cuts off the overcurrent. The pair of terminal portions F2 extend in a plate-like shape in directions away from each other from the body portion F1.

As shown in fig. 5 and 6, the fuse F mounted on the lower base 34 is disposed so as to connect the right end of the first relay bus bar 35 and the first negative branch bus bar 73 in the left-right direction. The fuses F are electrically connected to each other by screwing the terminal portions F2 to the lower base 34 together with the first relay bus bar 35 and the first negative electrode branch bus bar 73.

On the other hand, as shown in fig. 8, 9, 11, and 12, the fuse F mounted on the component mounting portion 51 is disposed so as to connect the second relay bus bar 52 and the second negative branch bus bar 75 in the left-right direction. The fuses F are electrically connected to each other by screwing the terminal portions F2 to the component mounting portion 51 together with the second relay bus bar 52 and the second negative branch bus bar 75.

[ Wiring harness 90]

As shown in fig. 1, the wire harness 90 has a pair of electric wires 92, a pair of terminals 94, and a connector 96.

The electric wire 92 is a general coated electric wire in which a core wire is covered with an insulating coating layer. As shown in fig. 5 to 7, one wire 92 of the pair of wires 92 is a positive wire 92P connected to the positive side, and the other wire 92 is a negative wire 92N connected to the negative side.

A terminal 94 is electrically connected to the tip end of each wire 92 by crimping.

The pair of terminals 94 are each formed of a metal having conductivity. The terminal 94 connected to the positive electrode wire 92P is screwed to the positive electrode branch bus bar 72 and electrically connected thereto. The terminal 94 connected to the negative electrode wire 92N is electrically connected by being screwed to either the first negative electrode branch bus bar 73 or the second negative electrode branch bus bar 75.

The connector 96 is electrically connected to rear end portions of the pair of electric wires 92. The connector 96 is fixed to the connector mounting ports 32B, 42B of the lower case 30 and the upper case 40 in a water-tight state. Thereby, the two harnesses 90 are mounted to the lower case 30 and the upper case 40 in a water-sealed state.

As shown in fig. 5 and 6, the terminals 94 of the negative-electrode wires 92N of the two wire harnesses 90 attached to the lower case 30 are screwed to the right-side end portions of the first relay bus bars 35 in the lower base 34 and connected. Thus, the two wire harnesses 90 attached to the lower case 30 are electrically connected to the negative electrode bus bar 61N via the first negative electrode branch bus bar 73, the fuse F, and the first relay bus bar 35.

On the other hand, as shown in fig. 5 and 7, the terminals 94 of the negative electric wires 92N in the two wire harnesses 90 attached to the upper case 40 are screwed and connected to the lower end portions of the second relay bus bars 52 of the component mounting portion 51. Thus, the two wire harnesses 90 mounted to the upper case 40 are electrically connected to the negative electrode bus bar 61N via the second negative electrode branch bus bar 75, the fuse F, and the second relay bus bar 52.

Therefore, as shown in fig. 5 and 6, two sets of lower branch circuits 70L are housed in the lower case 30, and each lower branch circuit 70L includes a lower negative electrode circuit 70LN including the negative electrode wire 92N of the wire harness 90, the first relay bus bar 35, the fuse F, and the first negative electrode branch bus bar 73, and a lower positive electrode circuit 70LP including the positive electrode wire 92P of the wire harness 90 and the positive electrode branch bus bar 72.

As shown in fig. 5 and 9, most of the two sets of upper branch circuits 70U are housed in the upper case 40, and each upper branch circuit 70U includes an upper negative electrode circuit 70UN including the negative electrode wire 92N of the wire harness 90, the second relay bus bar 52, the fuse F, and the second negative electrode branch bus bar 75, and an upper positive electrode circuit 70UP including the positive electrode wire 92P of the wire harness 90 and the positive electrode branch bus bar 72.

That is, lower branch circuit 70L disposed in lower case 30 and upper branch circuit 70U disposed in upper case 40 are arranged so as to overlap in the vertical direction, and branch circuit 70 branched from power supply circuit 60 is configured.

[ replacement procedure of fuse ]

In the electrical junction box 10 of the present embodiment, with the above configuration, an example of a procedure for replacing the fuse F in the upper branch circuit 70U will be described next, and an example of a procedure for replacing the fuse F in the lower branch circuit 70L will be described next.

To replace the fuse F in the upper branch circuit 70U disposed in the upper case 40, first, the four bolts BT attached to the cover 23 are removed. As shown in fig. 11 and 12, when the cover 23 is removed from the top plate 41, the first working hole 44 is exposed, and the fuse F of the upper negative electrode circuit 70UN disposed on the component mounting portion 51 of the upper base 50 faces upward from the first working hole 44. Thus, the operator can easily perform the replacement operation of fuse F of upper negative electrode circuit 70UN through first work hole 44.

Next, in order to replace the fuse F of the lower negative electrode circuit 70LN disposed in the lower case 30, the four bolts BT of the fixing portion 53 of the upper base 50 are removed through the first working hole 44. Then, as shown in fig. 13 and 14, the upper base 50 is removed upward through the first working hole 44.

Here, since the negative electrode wire 92N of the wire harness 90 attached to the upper case 40 is connected to the second relay bus bar 52 disposed on the component mounting portion 51 of the upper base 50 via the terminal 94, the upper base 50 is detached so as not to apply a tensile load to the negative electrode wire 92N and the terminal 94 of the wire harness 90.

Then, in the upper base 50, the second working hole 49 of the closed base receiving portion 45 is opened. Accordingly, fuse F of lower negative electrode circuit 70LN fixed to lower base 34 is in a state of facing upward through second work hole 49 and first work hole 44. Thus, the operator can easily perform the replacement operation of fuse F of lower negative electrode circuit 70LN through second work hole 49 and first work hole 44.

That is, in the present embodiment, by detaching cover 23 from upper case 40, only upper base 50 of fuse F on which upper branch circuit 70U is disposed can be exposed. By removing the upper base 50 of the upper case 40, only the lower base 34 of the fuse F in which the lower branch circuit 70L is disposed can be exposed.

That is, the present embodiment can improve the waterproofness of the electrical junction box 10 and improve the workability of replacing the fuse F, compared to, for example, an electrical junction box in which the fuse is replaced in a state where the upper case is removed from the lower case and the upper branch circuit and the lower branch circuit are largely exposed.

As described above, the present embodiment is an electrical junction box 10 including a case 20, a power supply circuit 60, and a branch circuit 70, the branch circuit 70 being a circuit that has a removable fuse (overcurrent cutoff element) F and branches from the power supply circuit 60, the case 20 including a case main body 21, a cover 23 removable from the case main body 21, and a cover sealing member 24, the case main body 21 including a first working hole 44, the power supply circuit 60 and the branch circuit 70 are housed, and as shown in fig. 8 to 10, the first working hole 44 is formed to have an outer dimension smaller than an outer dimension of the top plate 41 so as to penetrate the top plate 41 of the case main body 21 at a position where the fuse F faces upward (outward), the cover 23 is attached to the case main body 21 so as to close the first working hole 44 in a watertight state, and the cover sealing member 24 is in close contact with the peripheral edge portion of the first working hole 44 in the case main body 21 and the cover 23.

As shown in fig. 11 and 12, the fuse F is in a state of facing upward from the first working hole 44 by detaching the cover 23 from the housing main body 21, and therefore the fuse F can be easily replaced through the first working hole 44. This makes it possible to improve the workability of replacing the fuse F. The first working hole 44 is formed to have an outer dimension smaller than an outer dimension of the top plate 41 of the case main body 21, and the cover 23 closes the first working hole 44 in a liquid-tight state when the cover 23 is attached to the case main body 21. This can improve the waterproof property of the electrical junction box 10, for example, compared to a case in which the housing is largely opened.

The case body 21 includes a lower case 30, an upper case 40, and an elastic case sealing member 25, the lower case 30 and the upper case 40 are assembled with each other, the case sealing member 25 is in close contact with the lower case 30 and the upper case 40 to seal a space between the lower case 30 and the upper case 40 in a watertight state, the branch circuit 70 includes a lower branch circuit 70L disposed in the lower case 30 and an upper branch circuit 70U disposed in the upper case 40, the lower case 30 includes at least one connector 96 connected to the lower branch circuit 70L, the upper case 40 includes at least one connector 96 connected to the upper branch circuit 70U, and the lower branch circuit 70L and the upper branch circuit 70U are arranged in a direction in which the lower case 30 and the upper case 40 are assembled with each other, as shown in fig. 8.

For example, when connectors connected to the branch circuits are provided in the lower case and the upper case, respectively, the following methods are conceivable: most of the branch circuit is disposed in the lower case, and the branch circuit disposed in the lower case is connected to the connector disposed in the upper case by a wire. However, according to such a method, a region for arranging the upper case is secured only for providing the connector, which causes a dead space in the upper case and an increase in the size of the electric junction box as a whole.

In the present embodiment, however, lower branch circuit 70L to which connector 96 of lower case 30 is connected is disposed in lower case 30, and upper branch circuit 70U to which connector 96 of upper case 40 is connected is disposed in upper case 40. That is, by effectively using the waterproof case main body 21, the case main body 21 can be downsized, and the electric junction box 10 can be downsized.

The power supply circuit 60 is disposed in the lower case 30, and as shown in fig. 8 and 9, the upper branch circuit 70U has a second negative branch bus bar 75 (branch bus bar 71) connected to the power supply circuit 60.

For example, when assembling the lower case and the upper case, the electrical junction box that connects the electric wires of the upper branch circuit to the power supply circuit disposed in the lower case needs to secure an extra length housing area for housing the extra length of the electric wires in the case. Therefore, the housing is increased in size according to the amount of the extra-long storage area.

However, since upper branch circuit 70U of the present embodiment includes second negative branch bus bar 75 extending in the vertical direction and connected to power supply circuit 60, it is not necessary to secure an extra long storage area in case 20 when lower case 30 and upper case 40 are assembled, and case 20 can be downsized. This enables the electrical junction box 10 to be further reduced in size.

As shown in fig. 9, the upper case 40 has an upper base 50 on which the fuse F of the upper branch circuit 70U is disposed, the lower case 30 has a lower base 34 on which the fuse F of the lower branch circuit 70L is disposed, and the upper base 50 and the lower base 34 are arranged in the vertical direction (the direction in which the lower case 30 and the upper case 40 are assembled to each other).

Since the upper base 50 and the lower base 34 are arranged in the vertical direction, for example, the housing main body 21, that is, the electrical junction box 10 can be prevented from being enlarged in the vertical and horizontal directions, compared to a case where the upper base and the lower base are arranged offset in the vertical and horizontal directions intersecting the vertical direction.

The upper case 40 has a pedestal receiving portion 45 to which the upper pedestal 50 is detachably attached, and as shown in fig. 13 and 14, the pedestal receiving portion 45 has a second working hole 49 closed by the upper pedestal 50.

By detaching the upper base 50 from the base receiving portion 45, the lower base 34 can be made to face upward through the first working hole 44 and the second working hole 49. Therefore, the fuse F disposed on the lower base 34 can be replaced by the first work hole 44 and the second work hole 49. Thus, for example, compared to a case where the entire circuit including the power supply circuit is exposed and the fuse is replaced, the replacement operation of the fuse F can be performed satisfactorily while improving the waterproof property.

For example, when the bus bar of the upper branch circuit is connected to the power supply circuit when the lower case and the upper case are assembled, the connection between the bus bar and the power supply circuit cannot be visually confirmed by the case, and the workability of connection between the upper branch circuit and the power supply circuit is lowered.

However, in the present embodiment, the second negative branch bus bar 75 is provided to be detachable from the power supply circuit 60 through the first working hole 44, and therefore, for example, when the lower case and the upper case are assembled, the workability of connecting the power supply circuit 60 to the upper branch circuit 70U is superior to that when the bus bar of the upper branch circuit is connected to the power supply circuit.

< other embodiments >

The technology disclosed in the present specification is not limited to the embodiments described above and illustrated in the drawings, and includes, for example, the following various embodiments.

(1) In the above embodiment, the fuse F having the cylindrical body portion F1 is used as the overcurrent cutoff element. However, the present invention is not limited to this, and a fuse having a rectangular main body may be used as the overcurrent cutoff element.

(2) In the above embodiment, two wire harnesses 90 are attached to each of the lower case 30 and the upper case 40. However, the number of the wire harnesses attached to each housing is not limited to this, and may be one or three or more.

(3) In the above embodiment, the first work hole 44 and the cover 23, the second work hole 49, and the upper base 50 are formed in a rectangular shape. However, the present invention is not limited to this, and the hole and the cover, the second hole, and the upper base may be configured to have a circular shape, an oblong shape, or the like.

Description of the reference numerals

10: electrical connection box

20: shell body

21: shell body

23: cover

23A: side sealing surface of cover

24: sealing member for cover

25: sealing member for housing

30: lower casing

31: base plate

32: lower side plate

32A: front cable lead-in port

32B: connector mounting port

33: lower flange part

34: lower pedestal

35: first relay bus bar

36: sealing groove

37: bolt fastening part

40: upper shell

41: top board

42: upper side plate

42A: rear cable lead-in port

42B: connector mounting port

43: upper flange part

43A: sealing surface

44: first operation hole

44A: seal assembly rib

45: pedestal bearing part

47: mounting flange

48: bottom part

49: second working hole

50: upper pedestal

51: component mounting part

52: second relay bus bar

53: fixing part

60: power supply circuit

61: power bus bar

61N: negative bus bar

61P: positive electrode bus bar

62: first positive electrode part

63: second positive electrode part

64: third positive electrode part

65: a first negative electrode part

66: second negative electrode part

67: third negative electrode part

70: branch circuit

70L: lower branch circuit

70 LN: lower negative pole circuit

70 LP: lower side positive electrode circuit

70U: upper side branch circuit

70 UN: upper negative pole circuit

70 UP: upper side positive electrode circuit

71: branch bus bar

72: positive pole branch bus bar

73: first negative branch bus bar

75: second negative branch bus bar

90: wire harness

92: electric wire

92N: negative electrode wire

92P: positive electrode wire

94: terminal with a terminal body

96: connector with a locking member

BT: bolt

F1: main body part

F2: terminal section

F: and a fuse.