JP2020127302A - Electric connection box - Google Patents

Abstract

To provide an electric connection box which can efficiently radiate heat while being miniaturized.SOLUTION: An electric connection box performs relay when power to be supplied is distributed to a plurality of load devices, and comprises: a housing which has a heat radiation wall; a first heating component and a second heating component which are arranged in the housing to generate heat by power supply; and a connection conductor which connects the first heating component with the second heating component. The connection conductor has: a first conductor part which extends from the first heating component to the second heating component to contact the first heating component and the second heating component; and a second conductor part which extends from the first conductor part to the heat radiation wall to transmit the heat of the first heating component and the second heating component to the heat radiation wall.SELECTED DRAWING: Figure 3

Description

The present disclosure relates to electrical junction boxes.

Conventionally, a power line in a hybrid vehicle or an electric vehicle is provided with a plurality of electronic parts such as a relay and a fuse, and each electronic part is used to turn on/off the power line or to cause an overcurrent in the power line. At that time, the circuit is cut off. It is generally known that these electronic components are housed in an electric junction box. In the electric junction box, from the viewpoint of miniaturization, the electronic components are arranged close to each other, and a connection conductor such as a bus bar is used to connect the power supply lines in the electronic components arranged close to each other.

However, when an electric current flows through each electronic component, each electronic component generates heat, so that the heat of each electronic component is concentrated and transmitted to the connecting conductors connecting them. Moreover, when the amount of current to the electrical junction box increases due to the increase in the output of charging/discharging power, the amount of heat generation tends to increase. Therefore, it is necessary to efficiently dissipate the transferred conductor.

For example, in Patent Document 1, each of the connection conductors extending from the first electronic component and the connection conductor extending from the second electronic component are fastened to a heat transfer member that transfers heat to the heat radiating portion, thereby connecting the connection conductors. The plurality of electronic components are dissipated through the.

Further, in Patent Document 2, a heat transfer member that comes into contact with both of the connection conductor extending from the first electronic component and the connection conductor extending from the second electronic component is provided in the cooling unit, so that each connection conductor is interposed. The plurality of electronic components are radiated.

JP, 2008-98007, A JP, 2005-84609, A

However, in the case of the above technique, since the heat transfer member is provided separately from the connection conductor, the heat dissipation efficiency decreases due to the thermal resistance between the members. Further, a space for providing the heat transfer member is required between the electric connection box and a plurality of electronic components, which makes it difficult to reduce the size of the electric connection box. In addition, if the cross-sectional area of the connection conductor is increased in consideration of the heat dissipation of the connection conductor, it may lead to an increase in the size, weight and cost of the electrical junction box.

An object of the present disclosure is to provide an electric connection box that can be efficiently radiated while being downsized.

The electrical junction box according to the present disclosure,
An electrical junction box that relays when distributing the supplied power to a plurality of load devices,
A housing having a heat dissipation wall,
A first heat generating component and a second heat generating component that are disposed in the housing and generate heat by being supplied with the electric power;
A connection conductor connecting the first heat-generating component and the second heat-generating component,
Equipped with
The connection conductor is
A first conductor portion extending from the first heat-generating component to the second heat-generating component and contacting the first heat-generating component and the second heat-generating component;
A second conductor part that extends from the first conductor part to the heat dissipation wall and transfers heat of the first heat generating component and the second heat generating component to the heat dissipation wall;
Have.

According to the present disclosure, it is possible to efficiently radiate heat while reducing the size.

It is the figure which looked at the electric junction box concerning an embodiment of this indication from the top. It is the figure which looked at the electric connection box from which the lid was removed from above. It is an exploded perspective view of the 2nd bus bar and fuse in an electric junction box. It is the figure which looked at the 2nd bus bar part in a case from the back. FIG. 4 is a sectional view taken along line XX in FIG. 3. It is sectional drawing which shows the structure which fixed the 2nd bus bar with the fixing part. It is a figure showing the composition which fixed the 2nd bus bar with the fixed part and provided the heat transfer member. It is a figure which shows the 2nd bus bar which concerns on a modification. It is a figure which shows the 2nd bus bar which concerns on a modification. It is a figure which shows the 2nd bus bar which concerns on a modification. It is a figure which shows the 2nd bus bar which concerns on a modification. It is a figure which shows the 2nd bus bar which concerns on a modification.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. FIG. 1A is a diagram of an electric junction box 1 according to an embodiment of the present disclosure, as viewed from above. FIG. 1B is a view of the electric junction box 1 with the lid 10 removed, as seen from above.

1A and 1B is provided in a power system of a vehicle V such as a hybrid vehicle or an electric vehicle, and is connected to a vehicle ECU (Electronic Control Unit) and a plurality of load devices (not shown). The electric junction box 1 draws in a high-voltage power line or the like routed from each load device and relays when distributing the supplied power to a plurality of load devices.

Note that the plurality of load devices include a battery, an inverter, a DC/DC converter, a charging device, an electric compressor, a heater, a cooler, and the like.

The electric junction box 1 includes a lid 10, a housing 20, a circuit board 30, a current sensor 40, a first bus bar 50, a relay 60, a fuse 70, and a second bus bar 100. The lid 10 is fastened to the end surfaces of the four side walls 20</b>A that form the housing 20, thereby closing the opening portion of the housing 20.

The housing 20 is formed in a rectangular box shape having four side walls 20A and a bottom wall 20B (see FIG. 3). The housing 20 is made of metal and has a fixed portion 21 and a connector portion 22. The bottom wall 20B is a feature that corresponds to the “heat dissipation wall” of the present disclosure.

The fixed portion 21 is provided at the lower end portion of the side wall 20A (see also FIG. 2) and has a hole through which a screw passes. The electrical connection box 1 is fixed by inserting a screw through this hole to fasten the component for fixing the electrical connection box 1 and the housing 20. In the present embodiment, the fixed portions 21 are provided on the front side wall 20</b>A and the rear side wall 20</b>A of the housing 20, two in total, four in total.

The connector portion 22 is a portion connected to the vehicle ECU and the plurality of electric power modules, and is connected to the side wall 20A and the like by the number of devices connected to the electric junction box 1, such as the connected vehicle ECU and the plurality of load devices. It is provided.

Various circuits are mounted on the circuit board 30, and the circuit board 30 is arranged on the front side wall 20A in the housing 20.

The current sensor 40 is a Hall-type current sensor including a circular core (non-divided cylindrical magnetic core) (see also FIG. 2 ), and is arranged near the left end in the housing 20. ing.

The first bus bar 50 is made of metal and connects the relay 60 to an external device. The first bus bar 50 extends in the left-right direction, and has screws at both left and right ends, and holes through which projecting portions 61 of a relay 60 described later are inserted.

The first bus bar 50 is fixed in the housing 20 by being inserted into the core of the current sensor 40 and then having a screw or a protrusion 61 inserted into each of the holes (see FIGS. 2 and 3 as well). reference). As a result, the current sensor 40 can detect the current flowing through the first bus bar 50.

The relay 60 is a relay element provided on a power line connected to an external device, and switches the connection state of the power line to either ON or OFF under the control of the vehicle ECU. The relay 60 is arranged in the center of the housing 20 in the left-right direction near the rear side wall 20A.

As shown in FIG. 2, on the upper surface of the relay 60, two projecting portions 61 that pass through the holes of the first bus bar 50 and the holes 111 of the second bus bar 100 are provided.

The fuse 70 is an element that interrupts the circuit when an overcurrent flows through the power line, and is arranged near the right side wall 20A in the housing 20 (see FIG. 1B). The fuse 70 has a columnar main body 71 extending in the left-right direction, and a pair of connecting portions 72 protruding from both left and right ends of the main body 71.

A hole is formed in each of the pair of connecting portions 72. The left connecting portion 72 is connected to the second bus bar 100. A protrusion 131 of the second bus bar 100, which will be described later, is inserted into the hole of the left connecting portion 72. The right connecting portion 72 is arranged on the fixing portion 23 provided so as to project from the bottom wall 20B of the housing 20 (see FIG. 3). A screw is inserted into the hole of the right-side connecting portion 72 and is fastened to the fixing portion 23 together with a predetermined terminal. As a result, the fuse 70 is fixed in the housing 20.

The fixing portion 23 is made of an insulating member such as resin. When the fixing portion 23 is made of a conductive material, an insulating member is provided between the connecting portion 72 and a predetermined terminal and the fixing portion 23.

The second bus bar 100 is a metal plate-shaped member that connects the relay 60 and the fuse 70, and is configured by bending one plate-shaped member, for example. The second bus bar 100 has a first portion 110, a second portion 120, a third portion 130, a fourth portion 140, and a fifth portion 150. The second bus bar 100 corresponds to the “connection conductor” of the present disclosure.

The first portion 110 extends rightward from a position corresponding to the relay 60 and then extends forward. A hole 111 through which the protrusion 61 of the relay 60 is inserted is formed at the left end of the first portion 110. The second bus bar 100 is fixed to the relay 60 by inserting the projecting portion 61 into the hole 111 of the first portion 110 and fastening it with the nut 61A (see FIG. 3).

The second portion 120 extends downward from the front end of the first portion 110. The third portion 130 extends from the lower end of the second portion 120 to the front side. The protrusion 131 is provided on the upper surface of the third portion 130.

The protruding portion 131 is inserted into the hole of the connecting portion 72 of the fuse 70 and fastened with the nut 72A, whereby the fuse 70 is fixed to the second bus bar 100. As a result, second bus bar 100 contacts both relay 60 and fuse 70, and relay 60 and fuse 70 are electrically connected. The 1st part 110, the 2nd part 120, and the 3rd part 130 are equivalent to the "1st conductor part" of this indication.

As shown in FIGS. 2 and 3, the fourth portion 140 extends downward from the front end of the third portion 130, and extends to the insulating member 170 positioned on the bottom wall 20B of the housing 20. In other words, the fourth portion 140 extends from the predetermined end of the third portion 130 so as to be orthogonal to the bottom wall 20B.

As shown in FIGS. 3 and 4, the fifth portion 150 extends rearward from the lower end of the fourth portion 140 and parallel to the bottom wall 20B.

The fifth portion 150 is fixed to the housing 20 by the fixing member 160. The fixing member 160 is a plate-shaped resin and holds the fifth portion 150 with the bottom wall 20B. Holes are formed in the fixing member 160 on both the left and right sides of the fifth portion 150. The second bus bar 100 is fixed in the housing 20 by inserting the screw 161 into this hole and screwing it into the bottom wall 20B.

The fixing member 160 may be provided only for fixing the fifth portion 150, and is also used as a member having other uses such as a board on which a circuit pattern is mounted or a member for arranging components. May be.

A sheet-shaped insulating member 170 is arranged between the fifth portion 150 and the bottom wall 20B. This insulating member 170 suppresses electric leakage from the second bus bar 100 to the housing 20.

By fixing the second bus bar 100 to the housing 20 in this way, it becomes possible to transfer the heat of the second bus bar 100 to the bottom wall 20B of the housing 20. The fourth portion 140 and the fifth portion 150 correspond to the “second conductor portion” of the present disclosure. The fourth portion 140 corresponds to the “middle portion” of the present disclosure. The fifth portion 150 corresponds to the “heat transfer section” of the present disclosure.

Further, as shown in FIG. 4, the fifth portion 150 is provided in a region below the third portion 130 (see the broken line Y). In other words, the fifth portion 150 is within the range of the third portion 130 in the vertical direction and overlaps the range of the contact portion of the third portion 130 with the fuse 70. The length of the fifth portion 150 in the front-rear direction is equal to the length of the third portion 130 in the front-rear direction.

The function and effect of the electrical junction box 1 according to this embodiment configured as described above will be described. Since the fifth portion 150 of the second bus bar 100 is arranged on the bottom wall 20B of the housing 20 via the insulating member 170, the heat of the second bus bar 100 can be transferred from the fifth portion 150 to the bottom wall 20B. it can.

The heat transferred to the bottom wall 20B is released from the outer surface of the bottom wall 20B. That is, it is possible to dissipate heat from the second bus bar 100 via the bottom wall 20B.

Further, the relay 60 and the fuse 70 generate heat when electric power is supplied. The relay 60 corresponds to the “first heat generating component” of the present disclosure, and the fuse 70 corresponds to the “second heat generating component” of the present disclosure.

Since second bus bar 100 is in contact with relay 60 and fuse 70, heat generated by relay 60 and heat generated by fuse 70 are concentrated and transferred to second bus bar 100. In the present embodiment, the heat concentratedly transferred to second bus bar 100 is transferred to bottom wall 20B via fourth portion 140 and fifth portion 150. Thereby, the 2nd bus bar 100 can be efficiently radiated.

Here, as shown in FIGS. 5A and 5B, for example, it is assumed that the electric connection box 1 is provided with the bus bar 200 that does not have the fourth portion 140 and the fifth portion 150. The bus bar 200 has a first portion 210, a second portion 220, and a third portion 230.

The first part 210, the second part 220, and the third part 230 have substantially the same configuration as the first part 110, the second part 120, and the third part 130 of the second bus bar 100. Specifically, the first portion 210 extends rightward from the connection portion of the relay 60. The second part 220 extends downward from the right end of the first part 210. The third portion 230 extends rightward from the lower end of the second portion 220 and is connected to the fuse 70.

In the case of such a bus bar 200, for example, as shown in FIG. 5A, the fixing portion 23 is provided in the portion of the left side connecting portion 72 as in the case of the right side connecting portion 72 of the fuse 70. It is conceivable that the three parts 230 are fixed.

In this way, the portion of the third portion 230 of the bus bar 200 comes into contact with the fixed portion 23, but if the fixed portion 23 is made of resin from the viewpoint of leakage prevention, the heat transfer efficiency is poor and heat cannot be effectively radiated.

In contrast, in the present embodiment, third portion 130, fourth portion 140 and fifth portion 150 extend toward bottom wall 20B and transfer heat to bottom wall 20B. That is, in the present embodiment, since the space below the second bus bar 100 is used to dissipate heat, the heat dissipation efficiency can be improved compared to the configuration of FIG. 5A.

Further, in the case of the configuration in which the bus bar 200 is fixed to the fixing portion 23, it is conceivable to separately provide the heat transfer member 24 in the housing 20, as shown in FIG. 5B. In order to provide the heat transfer member 24, for example, it is necessary to increase the left-right direction length of the third portion 230 of the bus bar 200 to secure a space in the bus bar 200 that contacts the heat transfer member 24.

With this configuration, as the bus bar 200 is expanded, it is necessary to provide a space for disposing the heat transfer member 24 also in the housing 20. As a result, the electric junction box 1 may be increased in size, weight, and cost.

On the other hand, in the present embodiment, since heat can be transferred to the bottom wall 20B by the fifth portion 150, it is not necessary to separately provide a heat transfer member. As a result, in the present embodiment, the space for providing the heat transfer member can be omitted, so that the electrical junction box 1 can be downsized.

That is, in the present embodiment, it is possible to efficiently radiate heat while reducing the size of the electrical junction box 1.

In addition, since the fifth portion 150 extends in parallel with the bottom wall 20B, the space under the third portion 130 can be used to increase the area of the fifth portion 150. As a result, the heat dissipation efficiency of the second bus bar 100 can be further improved.

In addition, since the fifth portion 150 is provided within the range of the third portion 130, the space below the third portion 130 can be effectively utilized, and the space of the bottom wall 20B for providing the fifth portion 150 is maximized. Can be reduced. As a result, it is possible to contribute to downsizing of the electric junction box 1.

Further, since the length of the fifth portion 150 in the front-rear direction is equal to the length of the third portion 130 in the front-rear direction, the fifth portion 150 can be made as long as possible, so that the heat dissipation efficiency of the second bus bar 100 can be improved. It can be further improved.

Further, since the fourth portion 140 extends from the end portion of the third portion 130 in the direction orthogonal to the bottom wall 20B, it is not necessary to perform special processing, and thus the second bus bar 100 can be easily manufactured. ..

Further, since the second bus bar 100 is composed of the plate-shaped member, the second bus bar 100 can be easily manufactured by bending one plate-shaped member.

Further, since the second bus bar 100 is made of a plate-shaped member, the first portion 110, the second portion 120, the third portion 130, the fourth portion 140 and the fifth portion 150 can be integrally formed. As a result, this occurs when the conductively connecting portions (the first portion 110, the second portion 120 and the third portion 130) and the heat conducting portion (the fourth portion 140 and the fifth portion 150) are separate members. Since there is no heat resistance, heat dissipation efficiency can be improved. Moreover, the strength of the second bus bar 100 can be increased.

Further, since the second bus bar 100 transfers heat to the bottom wall 20B via the insulating member 170, it is possible to radiate heat from the second bus bar 100 while preventing electric leakage.

Further, since the second bus bar 100 is fixed to the bottom wall 20B by the fixing member 160, there is no need to perform a fixing process on the second bus bar 100, and thus the second bus bar 100 can be easily manufactured.

Further, the bottom wall 20B may have any structure, but may be provided with a heat dissipation member such as a heat sink. Further, a member for cooling the bottom wall 20B may be separately provided.

Although the fourth portion 140 extends from the front end portion of the third portion 130 in the above-described embodiment, the present disclosure is not limited to this, and the fourth portion 140 may extend from a portion other than the end portion of the third portion 130. good. For example, as shown in FIG. 6, the fourth portion 140A may extend from the central portion of the third portion 130 in the front-rear direction. The fourth portion 140A in this configuration is connected to the central portion of the fifth portion 150 in the front-rear direction.

Further, in the above-described embodiment, the fourth portion 140 extends so as to be orthogonal to the bottom wall 20B, but the present disclosure is not limited to this, and the fourth portion 140 may not be orthogonal to the bottom wall 20B. good. For example, as shown in FIG. 7, the fourth portion 140B may be configured to extend from the front end portion of the third portion 130 to the rear end portion of the fifth portion 150.

Further, in the above-described embodiment, the third portion 130 and the fifth portion 150 are connected only by the fourth portion 140, but the present disclosure is not limited to this. For example, as shown in FIG. 8, a front intermediate portion 140C connecting the front end of the third portion 130 and the front end of the fifth portion 150, the rear end of the third portion 130 and the rear end of the fifth portion 150. The third portion 130 and the fifth portion 150 may be connected by the rear intermediate portion 140D that connects the portion.

Further, in the above-described embodiment, the bottom wall 20B of the housing 20 is illustrated as the heat dissipation wall, but the present disclosure is not limited to this, and may be the sidewall 20A of the housing 20. In this case, for example, as shown in FIG. 9, the second bus bar 100 can be configured without the fifth portion 150. Specifically, the fourth portion 140 serves as a heat transfer wall extending parallel to the side wall 20A. Second bus bar 100 shown in FIG. 9 is similar to second bus bar 100 in the above-described embodiment, except that it has no fifth portion 150.

According to this, heat can be effectively transferred to the side wall 20A by the fourth portion 140. In addition, in FIG. 9, the illustration of the insulating member is omitted.

Further, in the above-described embodiment, the second bus bar 100 having the first portion 110, the second portion 120, and the third portion 130 as the first conductor portion has been illustrated, but the present disclosure is not limited to this, and the heat generation to be connected is not limited thereto. The shape of the first conductor portion may be appropriately changed depending on the component. For example, as shown in FIG. 10, the second bus bar 100 may not have the second portion 120 and the third portion 130.

The second bus bar 100 in this configuration includes a first portion 110, a fourth portion 140, and a fifth portion 150. The first portion 110 extends from the relay 60 to the fuse 70. The fourth portion 140 extends downward from the connection portion of the front end portion of the first portion 110 with the fuse 70. The fifth portion 150 extends parallel to the bottom wall 20B from the lower end of the fourth portion 140 and is provided within the range of the first portion 110.

Even with such a configuration, it is possible to efficiently radiate heat while reducing the size of the electric junction box 1 as in the above embodiment.

Further, in the above embodiment, the length in the front-rear direction of the fifth portion 150 was equal to the length in the front-rear direction of the third portion 130, but the present disclosure is not limited to this, and the front-rear direction of the third portion 130 is the same. It may be shorter or longer than the length. However, in consideration of downsizing and heat dissipation of the electric junction box 1, it is preferable that the length of the fifth portion 150 in the front-rear direction is equal to the length of the third portion 130 in the front-rear direction.

Further, in the above embodiment, the fourth portion 140 extends from the connection portion of the second bus bar 100 with the fuse 70 (second heat generating component), but the present disclosure is not limited to this. For example, the fourth portion 140 may extend from the connection portion of the second bus bar 100 with the relay 60 (first heat generating component).

Further, in the above embodiment, the relay 60 and the fuse 70 are illustrated as the first heat generating component and the second heat generating component, but the present disclosure is not limited to this, and the electronic component other than the relay 60 and the fuse 70 is the first. The heat generating component and the second heat generating component may be used.

Further, in the above-described embodiment, the second bus bar 100 is fixed to the housing 20 by sandwiching the fifth portion 150 with the bottom wall 20B by the fixing member 160, but the present disclosure is limited to this. Instead, the second bus bar 100 may be fixed to the housing 20 by another method.

In addition, in the above-described embodiment, the second bus bar 100 is configured by the plate-shaped member, but the present disclosure is not limited to this, and may not be configured by the plate-shaped member. Further, when the second bus bar 100 is not composed of a plate-shaped member, the first conductor portion and the second conductor portion may be separate bodies. However, in consideration of the ease of manufacturing the second busbar 100 and the strength of the second busbar 100, it is preferable that the second busbar 100 be formed of a plate-shaped member.

In addition, each of the above-described embodiments is merely an example of an embodiment in carrying out the present disclosure, and the technical scope of the present disclosure should not be limitedly interpreted by these. That is, the present disclosure can be implemented in various forms without departing from the gist or the main features thereof.

INDUSTRIAL APPLICABILITY The electric junction box of the present disclosure is useful as an electric junction box capable of efficiently radiating heat while being downsized.

DESCRIPTION OF SYMBOLS 1 Electrical connection box 10 Lid 20 Housing 20A Side wall 20B Bottom wall 21 Fixed part 22 Connector part 23 Fixed part 30 Circuit board 40 Current sensor 50 First bus bar 60 Relay 61 Projection 70 Fuse 71 Main body 72 Connection 100 Second Bus bar 110 1st part 111 Hole 120 2nd part 130 3rd part 131 Projection part 140 4th part 150 5th part 160 Fixing member 170 Insulating member

Claims (7)

An electrical junction box that relays when distributing the supplied power to a plurality of load devices,
A housing having a heat dissipation wall,
A first heat generating component and a second heat generating component that are disposed in the housing and generate heat by being supplied with the electric power;
A connection conductor connecting the first heat-generating component and the second heat-generating component,
Equipped with
The connection conductor is
A first conductor portion extending from the first heat-generating component to the second heat-generating component and contacting the first heat-generating component and the second heat-generating component;
A second conductor part that extends from the first conductor part to the heat dissipation wall and transfers heat of the first heat generating component and the second heat generating component to the heat dissipation wall;
Have
Electrical junction box. The second conductor portion has a heat transfer portion that extends in parallel with the heat dissipation wall and transfers the heat to the heat dissipation wall.
The electrical junction box according to claim 1. The second conductor portion has an intermediate portion that extends from the first conductor portion toward the heat dissipation wall and is connected to the heat transfer portion,
The heat transfer part is within the range of the first conductor part in a direction perpendicular to the heat dissipation wall, and is in contact with at least one of the first heat generating component and the second heat generating component in the first conductor part. Overlap with the contact area
The electrical junction box according to claim 2. The intermediate portion extends from a predetermined end of the first conductor portion so as to be orthogonal to the heat dissipation wall,
The electrical junction box according to claim 3. The connection conductor is composed of a plate-shaped member,
The electrical junction box according to any one of claims 1 to 4. An insulating member disposed between the second conductor portion and the heat dissipation wall,
The second conductor portion transfers heat to the heat dissipation wall via the insulating member.
The electrical junction box according to claim 1. A fixing member for fixing the second conductor section to the housing by sandwiching the second conductor section between the second conductor section and the heat dissipation wall;
The electrical junction box according to claim 1.

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